SA Mechanical Engineer Oct11

THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 61 October 2011 1

www.bmgworld.net

2 THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 61 October 2011

www.astafrica.com


AN ENGINEER’S VIEW

Chris ReayChairman of the Working

Committee: Communications(SA Institution of Mechanical

Engineering)

Calories vs Nutrition

Of concern is the dominance of symptomatic solutions in the medical profession. In a crude sense, similarity may be illustrated

by putting thicker oil in a noisy gearbox. It may deaden the noise but it will not repair the defect or remove the root cause.

In a bioengineering analogy, we see the human frame in a similar light. Well cast in its original form, but through bad use and overstress, it exhibits damage which is exposed by illness, fatigue, disease and eventual cessation of life. Medical science has developed various repair procedures but many are largely the treatment of the symptom only. How many can actually

benefit the process at cell level, the equivalent grain level of engineering materials?

Mass farmingRecent statistics from the USA reveal that the general health level of the population is steadily decreasing. The metrics are essentially the incidences of non-communicable diseases, obesity and malnutrition. This results in the growing cost of breakdown main-tenance or more precisely, the cost of sickness care, which is escalating at a rate that is now becoming unaffordable and adding substantially to the social debt crisis in the USA. This is big business for the pharmaceutical companies and the medical profes-sion, who appear to resist any move to change from breakdown maintenance to what engineers would call a preventive maintenance regime, or in social terms, a wellness care regime. In a year 350 million Americans use 4 billion medical prescriptions.

The research has also determined that the main cul-prit in deteriorating health levels is a result of, most surprisingly, malnutrition! Of concern is the signifi-cant drop in natural nutrient levels of food products over the last two decades which is attributed to the

Bioengineering can be defined as the “application of concepts and methods of physics, chemistry, mathemat-ics, and computer science to solve problems in life sciences using engineering’s own analytical and synthetic methodologies”. (Wikipedia) So mechanical engineers, bred on a diet of root cause studies, problem solving, analysis, synthesis and ultimately constructing working and sustainable devices, are becoming more involved in the sciences of bioengineering. An especially important application is the analysis and cost-effective solu-

tions of problems related to human health.

practices of mass farming, synthetic fertilisers, toxic spraying, early harvesting, processing and storage. An orange for example from this process in 2000 contained about 70% of the nutrition value of your naturally grown and harvested orange in 1970. A continuous decline is still occurring. Processed food is regularly enhanced with synthetic supplements, most of which we are unaware.

Enter science with an engineering mindset. Is there a correlation between deteriorating health levels and modern food nutrition levels, and if so, in what way does this affect the system? As the essential nutrients have decreased, our cells have been deprived of most of the sugars needed for them to thrive and support their immune and communication functions. Synthetic supplements and vitamins do not provide the deficiency, and if one cares to study how synthetic vitamins are made, you would be brave to use them again. It is estimated that over 80% of the population in the USA consume synthetic vitamins.

Turnaround successScience has now developed a process of extracting the missing nutrients from real plant food based supplements that can provide the cell support role. Many cases, failed or abandoned under conventional medical treatment, have shown remarkable turn-around success. It seems evident that if the cells are in design condition, the rest of the structure will behave and even restore itself reliably. Big pharma and big food are trying to suppress this development for obvious reasons.

Will we see a move towards a wellness care regime internationally, or will we continue to pursue a sickness care regime? It is effectively preventive vs breakdown maintenance. Glyconutrient technology is leading this change, and should be supported by an informed and concerned public.

The main culprit in deteriorating health levels is a result of, most surprisingly, malnutrition!


mailto:[email protected]


Monthly Column8 Explore the World in Luxury

Cover Story11 Participation Across the Board

Power Transmission15 Online Gearbox Maintenance

Computers in Engineering17 Power Computing for All20 Making Pipe System Design Easier

POWER GENERATION TODAY23 Mining Coal Differently27 Power Generation News

Produced by:PROMECH PUBLISHING,P O Box 373, Pinegowrie, 2123Republic of South AfricaTel: (011) 781-1401, Fax: (011) 781-1403Email: [email protected]: www.promech.co.zaManaging Editor Susan CustersEditor Kowie HammanAdvertising Louise TaylorAdvertising: Power Generation Today Mark BennettCirculation Catherine MacdivaDTP Zinobia Docrat, Yolanda FlowerdayDisclaimerPROMECH Publishing and The South African Institution of Mechanical Engineering as well as any other body do not take responsibility for the opinions expressed by individuals.Printed by: Typo Colour Printing, Tel: (011) 402-3468/9

Official Publication ofTHE SA INSTITUTION OF MECHANICAL ENGINEERINGand endorsed by:

CORROSION INSTITUTE OF SA SA PUMP MANUFACTURERS ASSOCIATION SA VALVE AND ACTUATORS MANUFACTURERS ASSOCIATION THE SA INSTITUTE OF TRIBOLOGY NUCLEAR INSTITUTE SA INSTITUTE FOR NON-DESTRUCTIVE TESTING NATIONAL SOCIETY OF BLACK ENGINEERS INSTITUTE FOR CERTIFICATED MECHANICAL AND ELECTRICAL ENGINEERS SOUTH AFRICAN ASSOCIATION OF CONSULTING ENGINEERS ASSOCIATION OF SOCIETIES FOR OCCUPATIONAL SAFETY AND HEALTH

Pipes, Pumps and Valves29 Slurry Solution33 Special Pumps for Special Duties

Regulars3 An Engineer’s View

6 Institution News

28 Nuclear Institute (SA Branch)

32 SAINT

35 SAIT

37 SAPMA

38 Market Forum

46 On the Move

Contents

The monthly circulation is 4 242

CopyrightAll rights reserved. No editorial matter published in “SA Mechani-cal Engineer” may be reproduced in any form or language without written permission of the publish-ers. While every effort is made to ensure accurate reproduction, the editor, authors, publishers and their employees or agents shall not be responsible or in any way liable for any errors, omissions or inaccuracies in the publication, whether arising from negligence or otherwise or for any consequences arising therefrom. The inclusion or exclusion of any product does not mean that the publisher or editorial board advocates or rejects its use either generally or in any particular field or fields.

October 2011 VOLUME 61 NUMBER 10

On the cover:

Bearing Man GroupTel: 031 576 6221

Email: [email protected]

www.bmgworld.net


Council 2011/2012

Office BearersPresident .......................... . . . . . . . . . . . . . . . . . . . . . . . . G Barbic (George)Vice President ............................ . . . . . . . . . . . . . . . ... D Findeis (Dirk)National Treasurer ............................... KK Nyangoni (Kudzai)

Branch ChairpersonsCentral ..................................... . . . . . . . . . . . . . . . . . M Cramer (Mike)Eastern Cape ................................................ W Rall (William)KwaZulu/Natal ................................................. J Moto (John)Mpumalanga Highveld.............................. L Odendaal (Louis)Western Cape ........................................... Dr D Blaine (Debbie)

Portfolios:Communications/Strategic Planning/Specialist Group..................................................CD Reay (Chris)Young Engineers Forum................Prof B Collier-Reed (Brandon)Education: Universities of Technology............... E Zawilska (Ewa)Membership .................................................... E Zawilska (Ewa)Professional Development Programme..........M Black (Malcolm)Technology Programme ................................. SZ Hrabar (Steve)To be confirmed....................................................A Roos (Andre)To be confirmed.........................................G Bartholomew (Bart)

Chief Executive Officer: Vaughan Rimbault

National Office Manager: Anisa Nanabhay

PO Box 511, Bruma, 2026

Tel: (011) 615-5660, Fax: (011) 388-5356

Email: [email protected]

Website: www.saimeche.org.za

Membership: Central, Eastern Cape, Mpumalanga & KZN:

[email protected]

Membership: Western Cape: [email protected]

Company Affiliates

Alstom Power Service SA

Babcock Africa Limited

Bateman Engineered Technologies

Bosch Projects

Fluor SA

GEA Air-cooled Systems

Hansen Transmissions SA

Hatch Africa

Howden Power

Howden Projects

Industrial Water Cooling

MBE Minerals (SA) (Pty) Ltd (previously KHD Humboldt Wedag SA)

Megchem Eng & Drafting Services

THE SA INSTITUTION OF MECHANICAL ENGINEERING

Osborn Engineered Products SA

Rotek Engineering

RSD a division of DCD-Dorbyl

S.A.M.E Water

Sasol Technologies

SEW Eurodrive

Siemens

SNC-Lavalin SA

Spicer Axle SA

Spirax Sarco SA

Thyssenkrupp Engineering

Transvaal Pressed Nuts & Bolts

Ultra-Flow Engineering Services

Vital Engineering

Weir Minerals Africa

Winder Controls

John Orr Lecture 2011

“BLOODHOUND SUPERSONIC CAR” by Wing Commander Andy Green

SAIMechE hosts this very prestigious “John Orr Memorial Lecture” each year to commemorate the achievements of Professor John Orr (1870 – 1954) in engineering education in South Africa. The history of this prestigious lecture dates back to 1961 when the first lecture was initiated to honour Professor Orr.

This year the John Orr Lecture will be delivered by Wing Commander Andy Green.

Andy, Bloodhound SSC driver and team member, is the current holder of the World Land Speed Record, and the only person who has driven at supersonic speeds on land.

Andy is a Fighter Pilot in the Royal Air Force. He is a mathematician (first class honours degree from Oxford University) and an integral part of the Bloodhound SSC team.

The Bloodhound SSC project is an attempt to reach a speed of 1000 mph on land, and break the cur-rent land speed record in 2012/2013. The location has already been decided as Hakskeen Pan in the Northern Cape.

Bloodhound SSC Mission: To confront and overcome the impossible using science, technology, engineering and mathematics - To motivate the next generation to deal with global 21st century challenges.

Full information is available on the SAIMechE website - www.saimeche.org.za, then go to Calendar, and see above event listings, or contact Anisa at our National office on (011) 615-5660.

The lecture will be held at the following centres:

Johannesburg: University of the Witwatersrand (Wits University)

15 Nov 2011

Northern Cape: Kimberley (William Humphreys Art Gallery)

17 Nov 2011

Cape Town: University of Cape Town (UCT)

22 Nov 2011

Port Elizabeth: Nelson Mandela Metropolitan University (NMMU)

23 Nov 2011

Durban: University of KwaZulu Natal (UKZN)

24 Nov 2011

www.saimeche.org.za


THE SA INSTITUTION OF MECHANICAL ENGINEERING

SAIMechE Offers the Following Career Development Workshops General Event Enquiries: Carey Evans Tel 031 764 7136,

Email [email protected] Event Enquiries: Linda Robinson, Tel 031 764 7136, Email [email protected]

Two Day: Leadership & Management Principles & Practice in Engineering WorkshopCPD Validation Number: SAIMechE-0451-06/14

Course leader : David Ramsay, BSc. Eng. (Civil) University of Cape Town (UCT) 1978, Master of Engineering Management, UCT 2001, Diploma in Life & Busi-ness Coaching, The Coaching Centre 2006.

Amongst other positions he has held over his career, he was director of water services for the City of Cape Town in which he managed some 2500 staff and a

budget of R1,5bn. He has been responsible for numerous large water engineering projects in Cape Town, the most no-table being the Riviersonderend/Faure Water Scheme which won the South African Institute of Civil Engineers Award for excellence in 1994.

The method of instruction includes posed questions, power point presentations, one-on-one and group engagement, experiential learning and reflection. It covers all the primary learning styles in order to engage all participants in a mean-

ingful growth experi-ence. A learning guide, pre-course notes and an exercise are sent to the delegates before the course. Further handouts and exercise sheets are provided dur-ing the course. Recent delegates’ comments included: “Highly rec-ommended”, “Every-thing about the course, its presentation & the group participation was beneficial”, “Notes very

thoroughly prepared & format useful”, “I was engaged & chal-lenged”, “A very enlightening course which I will recommend to my colleagues” and “The interaction, topical examples and practicality was great.”

Animated delegates at a recent ‘Leader-ship’ workshop in East Rand

Two Day: How to Apply TRIZ to Solve Complex Technical Problems and Contradictions in Industry and Manufacturing WorkshopCPD Validation Number: SAIMechE-0450-06/14

Course Leader: Jac Spies, Gradu-ate of Business and Project Management - UNISA Business School, and Mathematics - University of Pretoria. Member of the Institute of Management Consultants of South Africa. Current lecturer at Continuing Education Institute of the Uni-versity of Pretoria and Midrand Graduate Institute.

The overall objective of the course is to provide the delegates with sufficient knowledge and skills to solve complex problems inventively that are crucial for survival and growth in a highly competitive world.

The course teaches leading edge methodologies, and its tools, to solve complex problems inventively in a systematic way.

The course in constructed around the Theory of Inventive Problem Solving developed by Genrick Altshuller, known globally as TRIZ, on how to leverage the mind to enable inventive problem solving.

The new knowledge and hands-on skill development em-powers the delegates to find inventive solutions for complex problems in less time compared with customary methods.

On completion of the course the delegate will understand (a) why inventive problem solving is crucial in industry for survival and growth, (b) how to leverage their mind to en-able inventive problem solving, (c) and apply Altshuller’s fundamental inventive principles and discoveries, (d) technical contradictions and how to apply the contradiction parameter matrix and the inventive principles to resolve complex problems inventively, (e) physical contradictions and how to apply the separation principles to find inventive solutions for complex problems (f) technology evolution trends to develop an insight into emerging technologies,(g) and apply maturity curves, (h) problem exploration models, (i) and apply ideality and the ideal final result algorithms.


OILS & LUBRICATIONMONTHLY COLUMN

In the international boat building market, Cape Town is the main centre attraction, not

only in terms of new trend-setting designs for catamaran yachts, but also as far as

performance of these boats is concerned.

One of the companies regularly making the cover pages of sailing and yacht-ing magazines across the globe with unique new designs in luxury yachting is

Gunboat boat builders based in Epping, near Cape Town. “SA Mechanical Engineer” visits the factory to talk to head designer, Patrick Hemp, about their range of cruising boats which have made waves around the world.

Speed and comfort“Our Gunboat 66 is a sturdy 66 footer which will take you to the most amazing distant corners of the world quickly, yet provide all the luxurious home comforts you want once you get there,” he says. “Although it is a fast boat, it’s not really a sail rac-ing vessel as such, but rather a custom-fitted boat with all the goodies, gadgets and comforts which each owner prefers to have when anchoring in some remote corner of the globe.”

Our first reaction to their name is that the com-pany must build military-type boats, but Patrick explains that Gunboat is derived from the boat racing practice where the first boat across the line is acknowledged by a gunshot from the ‘gunboat’ demarcating the finishing line. The company belongs to American, Peter Johnstone who hails from a family entrenched in the international boat building industry. They chose Cape Town as the main facility to build the luxury customised version of various Gunboat models, while a facility in China has now been opened to produce a standard version of this popular multi-hull vessel.

Huge successIn catamaran terms, a 66-foot boat is a large yacht, equating to the comforts you’d find on a luxury 100-foot single hull sailing boat. The idea is, therefore, to have the ultimate fast-cruising luxury yacht which can be sailed solo from a practical cockpit behind the mast, while not imposing on the creature comforts of the main entertainment and living spaces.

“The first Gunboat was 62 feet and three of these were built,” explains Patrick. “We then designed and built six 48-foot versions before we settled on the Gunboat 66 we now manufacture on a regular basis. The Gunboat 90, a ninety foot long catamaran, was a once-off project we did a while back and not the sort of thing you get to build frequently. It was a huge success with some interesting challenges

A custom-fitted boat with all the goodies, gadgets and comforts which each owner prefers to have when anchoring in some remote corner of the globe

A Gunboat under sail

Explore the World in Luxury

Patrick Hemp, head designer at Gunboat in Cape Town


of its own because in boat building it’s not just a matter of scaling up the smaller ver-sion to get a successful bigger boat, it has to be designed in its own right.

TechnologyAs a designer Patrick has to constantly remain abreast of all types of technologies, not only marine, but also stuff like sound systems, lighting, ma-terials, engines, solar systems and lately also electric motors and power storage systems. “We’re currently investigating the possibility of driving sail-ing yachts purely with electric motors, for example,” explains Patrick. “Today’s battery technology has become very sophisticated. For example, you can re-charge a battery bank with just about anything as opposed to having to charge a lead battery pack with a diesel generator.

“So, apart from constantly charging the pack with solar power which is not used at the time, you could, for instance, reverse the electric motor to become a generator once you’re under sail power. The props turn the generator to create electricity to re-charge the battery bank. This only takes one knot off your cruis-ing speed which, when you’re cruising at 18 knots (33km/h), is negligible compared with what you save in return. The future possibilities are quite exciting, yachtsmen simply have to adopt a power management system to reap the benefits.”

Other featuresOnly when walking through the factory where three 66 model Gunboats are in various stages of completion, do we realise how big these guys are out on the floor as opposed to on the water. Patrick points out some features such as the es-cape hatch in the hull on the underside. Each of the two hulls has two escape hatches which are above the water line on the inside of the hull and under the platform which joins the two hulls. “The hatches are a way out for those inside the boat in the unlikely event of the boat capsising,” explains Patrick. “However, they can also be opened when the boat is anchored off in calm waters, allowing fresh cool air into the downstairs cabins when

With the rudder or dagger boards retracted, this boat draw less than two feet of water, making cruising in very shallow water a breeze

MONTHLY COLUMN

Exploring the world in the comfort of home

The luxury interior of the saloon with the helm in the background

you’re parked off in extremely hot conditions.”

A feature favoured by all is the Gunboat’s retractable rudders and dagger boards. “With the rudder or dagger boards retracted, this boat draw less than two feet of water, making cruising in very shallow water a breeze,” says Patrick in conclusion. “For sailing in shallow bays, the rudders may be par-tially raised without any adverse affect on steering. Imagine the shallow cruising grounds that are now open to explore, something just not possible with most other yachts.”

Patrick Hemp, Gunboat, Tel: (021) 535-3145, Email: [email protected]



www.ksbpumps.co.za


COVER STORY

BMG supplies all industry sectors with a comprehensive range of bearings, seals, power transmission components, electric and geared motors, as well as belting,

fasteners, filtration and hydraulics. These quality branded engineering components are enhanced by the company’s highly competent technical support and maintenance service.

“The Group’s BEE shareholding deal with aloeCap Limited and the Humulani Investments Share Incen-tive Trust in 2007 was a significant part of BMG’s

commitment to successful black participation in our business,” says Charles Walters, CEO of BMG. “This partnership has been effective in achieving increased preferential procurement, skills develop-ment and socio-economic advancements.

“BMG adheres to an integrated BEE strategy and continually strives to improve all aspects of the scorecard. The company strategically links socio-economic investments to skills development and progressive employment equity, to ensure sustain-able business performance within the ambits of the codes of good practice.”

BMG’s latest certificate, which complies with the Revised Mining Charter minimum ownership requirement of 25% +1 vote, is applicable to all

Participation Across the Board

Big news is that Bearing Man Group, a division of Humulani Marketing, has enhanced its certification as a BEE level five contributor to achieve recognition as a level three contributor this year.

Bearing Man Group has enhanced its certification as a BEE level five contributor to achieve recognition as a level three contributor this year. At the hand-over of the certificate are from left: Charles Walters, CEO, BMG, Xolile Rubushe, analyst, Bravura Consulting, Alana Bond, head of the sustainable development advisory division at Bravura and Alick Granger, business development manager, BMG

Claim BEE procurement recognition of 110% against all purchases


COVER STORY

BMG divisions and branches. The new accredited level 3 status means BMG customers can claim BEE procurement recognition of 110 % against all purchases.

Engineering hubsAnother important development for BMG has been

High efficiency motors have important advantages over standard electric motors

BMG Drives has introduced a new generation of energy efficient electric motors – the IE2 range - which is distinguishable by a yellow cowl.

“These new energy efficient IE2 electric motors, which replace BMG’s EFF1 range, ensure high efficiency, reduced energy consumption, extended motor life and low operating costs,” says Graeme Neilson, general manager, electric motors, BMG Drives. “These motors are most efficient when running at full load, where energy savings of up to 3% can be achieved. Energy savings of up to 30% can be achieved by ensuring that all other mating components, like the gearbox and couplings are energy efficient and correctly fitted.

“Apart from energy saving – a critical issue facing this country – high efficiency motors have important advantages over standard electric motors. These benefits include longer service life, suitability for voltage variation applications, reduced temperature rise and minimal maintenance requirements.”

BMG Drives has introduced a new generation of energy efficient electric mo-tors – the IE2 range - which is distinguishable by a yellow cowl

the recent opening of specialist engineering hubs throughout the country. These engineering hubs have been formed by the consolidation of BMG Drives and BMG Belting’s business to support the company’s ‘world class production efficiency’ initiative.

BMG’s eight engineering hubs, which are as-sembly and support operations, offer a combined

www.irsa.co.za



COVER STORY

The VibChecker portable instrument is designed for reliable on-site vibration measurement and assessment

technical expertise and value–added product solution, to enhance the company’s service in carefully identified regions. The company has taken important steps to enhance ef-ficiencies by merging its various engineering businesses into one division, under which these hubs now oper-ate. Services include the supply, installation and repair of gearboxes, electric motors, PVC, PU, transmission and rubber belting, rollers and idlers, as well as a complete range of modular belting, heat exchangers and oscil-lating systems.

By selectively combining condition based maintenance products and services, with maintenance techniques and upgrades to energy efficient products, the ef-

ficiencies of a plant can be significantly enhanced.

Veronique Bezuidenhout, Bearing Man Group, Tel: 031 576 6221, Email: [email protected], www.bmgworld.net

www.engen.co.za



mailto:salesSA@davidbrownlcom


POWER TRANSMISSION

where each gearbox’s service factor is calculated into the data in order to automatically notify the maintenance engineer of any upcoming maintenance requirements so that they can plan ahead for it,” elaborates Ute. “This means the engineer can order replacement parts in good time.”

The CDM system not only provides a complete overview of the entire stock of a company’s drives but also tags its condition. Apart from carrying a complete record of maintenance carried out in the past, it takes just a few mouse clicks to plan future maintenance intervals. Specific components can also be monitored and an alarm notification is automatically sent out via an SMS to a cellphone if its condition becomes critical. Once the technician gets there, there’s no need to crawl into confined spaces to get to the nameplate of the unit as all the data on the unit is already available online.

The system“The real beauty of this system is that the engineer

The client can access to all the technical detail as well as the historical maintenance data of each and every SEW gearbox on his plant

One of the reasons there are slip-ups in the regular maintenance of gearboxes is probably because keeping track of the paper work is a tedious task, especially as there are

literally hundreds of gearboxes just on a single mine, factory or processing plant.

This task can only be done properly by a full-time maintenance administrator, but most businesses simply don’t have one for vari-ous reasons. But clients of SEW Eurodrive

in Johannesburg no longer have to worry as the company has come up with a drive management solution which only requires an Internet connection.

Maintenance managementTo find out more “SA Mechanical Engineer” speaks to newly-appointed managing director of SEW Eu-rodrive in South Africa, Ute Bormann. “Complete drive management, or CDM, is a concept which has been rolled out very successfully in Europe and is now being introduced to our local clients,” she says. “Basically it’s an Internet portal to which each of our registered clients has access through a password protected login procedure.

“On this portal, the client can access all the tech-nical detail as well as the historical maintenance data of each and every SEW gearbox on his plant,” she adds. “To set up the listing, we undertake a survey of a client’s plant in order to list every single gearbox, complete with serial number, installation data, the maintenance records and future mainte-nance requirements. The portal will also indicate the exact location, which may not necessarily be on the main site, of each gearbox.”

Data anywhere, anytimeThus an engineer right there, out in the field can go onto the portal with a laptop or PDA cellphone to access all the information he could possibly want on a particular gearbox in terms of its specifications and maintenance requirements. “What’s more, we run this portal on a customised, dedicated SAP system

Online Gearbox Maintenance

Ute Bormann, managing director of SEW Eurodrive in South Africa


can then order the required part from right where he is on site through the portal,” says Ute. “This ultimately means companies can safely carry less spares stock because specific delivery times on the critical components are agreed on beforehand. This delivery time will also be indicated on the Internet portal at the time the engineer orders the component online directly from where he is on site.

“Every gearbox we sell from now will go onto this portal’s database which every registered client can then access from wherever he or she is,” Ute adds. “We’re currently busy with our first big project of this kind with a mining group where we’re auditing all their sites to log all currently-installed gearboxes and their data to establish the CDM system on a national basis.”

POWER TRANSMISSION

An alarm notification is automatically sent out via an SMS to a cellphone if its condition becomes critical

The new service centre in Johannesburg

Stay with the timesThis is the sort of technology that gets the young engineers in the field as ex-cited as it makes the new young MD of SEW. “Although I am young, and a female in this very male-orientated in-dustry, the industry knows me well from the many years I’ve been with the com-pany and they’ve immediately ac-cepted me,” says Ute. “I don’t have any intention of suddenly making

dramatic changes as the new MD, but we do aim to stay abreast by introducing modern technology like this to make life for our clients a little easier.”

Despite tough economic challenges, business has grown for SEW resulting in the establishment of a dedicated service centre at headquarters in Jo-hannesburg. “Although we’ve always had a repair area at the factory, we’ve now expanded it into a fully-fledged dedicated service centre,” explains Ute. “At the same time, the training centre has been extended and Rene Rose has been promoted to general manager of communications, in charge of our training programme, the Drive Academy.

Training“The concept is modelled on the Drive Academy in Germany,” says Rene. “Training is practice ori-entated and demand specific, covering theory but customers also have the opportunity to practice on up-to-date equipment. Here they can simulate what they experience in the field. A wide range of training courses are available and cover topics such as geared motor maintenance, condition monitoring and the basics of drive engineering. Other courses are more product specific and offer customers the advantage of a subject matter expert who is fully versed in the SEW Eurodrive product range and its applications.

“As a result of the skills shortage, you find people operating machinery who were not required to do so in the past,” she remarks in conclusion. “This, combined with the dynamic landscape of technol-ogy, makes training a necessity in today’s business world. Most importantly though, adequate training means less downtime for our customers.”

Rene Rose, SEW-Eurodrive, Tel: (011) 248-7000, Email: [email protected], Website: www.sew.co.za

Engineer PlacementsAre you looking for engineering resources?

Consider the following:• A specialist service • Operated by Professional Engineers • That speak engineering language • Has a large, live local skills database• A network with access to scarce skills• Advanced searching for future needs

Contact us for a win-win deal

[email protected]



COMPUTERS IN ENGINEERING

However, these designs can become highly complex, often bordering on the need for super computer speed and power.

But super costs money and is usually beyond the reach of small engineering companies. So an engineer may have the flair to solve a problem, but the ideas simply fly out the window, never to be built.

PlatformsThen Microsoft came along with a high performance computing (HPC) server platform where several servers form a powerful computing cluster capable of speeding up complex computations. The combined power of several standard servers running on the HPC platform broadened the computational horizon for many engineers and scientists without the usual need for specialised IT technicians to manage and maintain the system.

However, the basic architecture of these HPC clusters still consists of several servers networked together where each server in the cluster performs one or more specific task. Typically these clus-ter components include Head Nodes, Compute Nodes, a Job Scheduler and Broker Nodes.

Microsoft has now launched a version of the HPC platform, the Windows HPC Server 2008 R2, which makes it even easier for the average company to utilise more computing power. “SA Mechanical Engineer” meets with Riedwaan Bas-sadien, platform strategy manager at

Off-the-shelf desktops

Power Computing For All

3D has made the design of engineering solutions, from component level through to complete plants, so much easier for engineers who can now achieve much more

accurate end results, much more quickly while exercising their creative juices.

With the rise of cloud computing, the world of HPC is changing



you run a bit of code on an ordinary desktop PC running on Windows 7. This ‘bit of code’ manages all your other off-the-shelf desktops in the office running on Windows 7, as workstation nodes to make up a cluster to provide high performance computing capabilities.”

Desktop workstationsWhen an HPC cluster is composed entirely of compute nodes, the cluster ‘owns’ the nodes and can add users and administrators to the node as required. “The cluster administrator can also change the operating system, enforce updates, and generally administer the compute nodes in a cluster,” explains Riedwaan.

“A workstation node, however, is someone’s everyday computer, and is controlled by the enterprise adminis-trators and by the individual user. The cluster is simply ‘borrowing’ it when it isn’t being used, and can therefore make no substantive changes to the node. It

cannot add users or administrators, nor make any change that will affect the users who typically log on to and use the workstation.”

Sit idle every nightAdding workstations to a HPC environment, or us-ing them to create the first HPC environment in a company, means businesses use their computing resources more effectively and efficiently. “You have tens, hundreds, even thousands of Windows-based computers that sit idle every night,” says Riedwaan. “Now you can let them work on parallel computing tasks when they’d otherwise be doing nothing.

If you currently have an HPC cluster, adding work-stations allows you to expand your cluster for jobs that require more processing width without having to buy and licence dedicated compute nodes.

“Alternatively, creating a cluster of workstations allows you to benefit from the parallel processing capabilities of an HPC cluster without having to make a large initial investment in dedicated compute nodes,” he adds. “Another advantage of adding workstations to your HPC cluster is the ability to use 32-bit workstations as well as 64-bit. This al-lows you to target a 32-bit platform with specific applications that will run better there.”

Reaching for the skyOverall this means that the barrier of entry into HPC has been considerably lowered. “I see this as the first stage any company should take towards cloud computing which is set to become mainstream in South Africa in the coming months,” Riedwaan says. “We see cloud computing as the space where HPC is going to end up before long. Once a com-pany has established an in-house cluster for HPC, for example, the next step would be to utilise the

As workstation nodes to make up a cluster to provide high performance computing capabilities

The server room where the massive power and storage of cloud computing resides

Microsoft South Africa to learn more.

“In the past you needed to run a head node as the controlling master to manage parallel processing across several servers which make up the HPC cluster,” he explains. “On our new HPC platform


massive power and storage of cloud computing which is available out there at ridiculously low prices compared with building up your own capacity.”

Cloud computing provides computation, software, data access, and storage services that do not require end-user knowledge of the physical location and configuration of the system that delivers the services. To clarify, think of the electricity grid - end-users consume power without needing to understand the component devices or infra-structure required to provide the service.

Utilising resources“With the rise of cloud computing, the world of HPC is changing and companies should start taking advantage of the growing number of massive data centres now available in the cloud,” Riedwaan says. “Microsoft’s Windows Azure, coming to South Africa early next year, provides on-demand access to lots of virtual machines and acres of cheap storage, letting users pay only for the resources they use.

“The potential benefits for HPC are obvious, but rather than relying solely on your own on-premises computing resources, using the cloud gives you access to more compute power when you need it,” he adds in conclu-sion. “For example, suppose your on-premises systems are sufficient for most, but not all of your organisation’s workloads, or suppose one of your HPC applications needs even more processing power - rather than buying more machines, you can instead rely on a cloud data centre to provide extra computing resources on demand.”

Riedwaan Bassadien, Platform Strategy Manager, Microsoft South Africa, Tel: (011) 361-7633, Email: [email protected]

We see cloud computing as the space where HPC is going to end up before long


A typical server room where cloud computing utilises storage and computing power

www.bearings.co.za




Making Pipe System Design Easier

Despite a general shortage of engineers around the world, design is increasingly competitive. The engineer who can deliver first, is the one who gets the work.

The evolution of design tools, like 3D CAD software, finite element analysis and com-putational flow analysis software packages, are typical elements which give designers

the edge. Those who have kept up with software developments are the engineers who get the work, mainly because they can deliver accurate designs quickly, saving time and money for their clients.

Simulation softwareFluid Flow is a software package specifically for analysing the flow dynamics in pipe networks, now available in South Africa from Holt Consult-ing Engineers based in Randburg. “SA Mechanical Engineer” speaks to Gerald Holt to find out more.

“Various types of software programmes are com-monly used by engineers to design and simulate the flow of water in pipelines and pipe networks,” he says. “This type of software, often called pipe network analysis software, solves the flows and pressures throughout the pipe system, simulating the performance of line equipment such as pumps and valves.

“However, results from these solutions are usually for a ‘steady-state’ in that they only provide a ‘snap-shot’ of the system’s performance at a particular instant,” adds Gerald. “This snapshot is sufficient if pump and valve performance and fluid levels do not change over time. But, the example of a res-ervoir where the liquid level falls over time, forces the engineer to perform a sequence of calculations, iterating each steady-state condition through physi-cal input on the keyboard of his computer, which is a long and tedious task.

“In terms of software, the next logical step would be to automate this keyboard iteration sequence in order to speed up the analysis process,” elaborates Gerald. “This has been achieved with the latest version of FluidFlow3. Automation is achieved by means of its scripting module. Once the steady-state model has been developed, the scripting module allows for a time-based sequence of events to be programmed using a Pascal-type language specially developed for this purpose.

How it works“For instance, suppose a tank is discharging through a pipe under gravity flow due to the head or level in the tank, and you want to determine how long it would take for the liquid to fall between two spe-cific levels, then the script would work as follows,” Gerald explains. “Firstly, a time interval is selected while the cross-sectional area of the tank is known. Then the steady-state flow is calculated based on the starting level, allowing the volume discharged over the selected time interval to be calculated.

Thirdly, knowing the volume discharged and the cross-sectional area of the tank, the fall in liquid surface level is calculated to determine a new discharge rate based on the new liquid level. The

Gerald Holt of Holt Consulting Engineering

Those who have kept up with software developments are the engineers who get the work



script loops through this sequence of calculations until the set low level is reached. In this way, the total time it takes for the level to fall to the lower level, is determined. Such a script might even be extended to include a pump start to re-fill the tank, stopping at the high-level set point and repeating the filling and emptying process, thereby determining the number of pump starts per hour.

“For this simple arrangement, writing the script is relatively easy, but for anything more complicated, like a whole network of piping, the engineer needs to have good programming skills in Pascal and, of course, the time to write and debug such a script,” argues Gerald. “To overcome this problem, FluidFlow3 has a scripting module which assists the user with this programming requirement which speeds up the flow calculation process of complex pipe networks dramatically.”

An exampleGerald shows us a typical example of the sort of time-based simulations that can be done with Fluidflow3’s scripting capabilities. The basic, steady-state model is shown in Figure 1.

The system comprises a pumping ‘chain’. A pair of bore-hole pumps source water from an aquifer and deliver to an initial storage tank (Tank 1); water is then pumped via an end-suction centrifugal pump to second storage tank (Tank 2); and then via a third pump to a high level storage tank (Tank 3) which supplies a water treatment plant.

The pumps in the chain are controlled by high and low level sensors in the tanks. For example, the pump sourcing water from Tank 1 and delivering to Tank 2 can only operate if two conditions apply, namely: the water level in supply Tank 1 is above the set low level and

the water level in delivery Tank 2 is lower than the set high level. Over time, the pumps will stop and start as water levels change, and the change in water levels will be dependent on the water treat-ment plant demand.

Figure 2 shows the time based variation of tank water levels for a constant water treatment plant demand of 10 l/s over 200 minutes. Upper set level in Tanks 1 and 2 are 4.5m and lower set level is 0.1m; the values for Tank 3 are 3.0m and 0.5m respectively. At the start of the sequence, all tank levels are assumed to be at 1.0m depth but the system soon stabilises as can be seen from chart.

Figure 1: The pump “chain”

Figure 2: Water Treatment Plant Demand = 10 l/s

The next logical step would be to automate this keyboard iteration sequence in order to speed up the analysis process



A different scenario is shown in Figure 3 where the water treatment demand is set to 50 l/s, slightly lower than the maximum capacity of the end-suction centrifugal pumps and the combined

pumping capacity of the two bore-hole pumps. With the lower water treatment plant demand, Tanks 1 and 2 eventually fill and their levels remain almost full, but with the higher demand the levels in the Tanks 1 and 2 do not increase, but oscillate between the start level of 1.0m and nearly empty.

Other calculationsFluidFlow3’s scripting can also perform a risk analysis of a pipe network system. “If, for ex-ample, there is a pump failure or pipe break at any location, we can calculate how long the plant will continue operating before the buffer volumes of water run out,” explains Gerald. “From the charts you can see that if demand is high, there is very little buffer volume in Tanks 1 and 2, but if the demand is low then the water treatment plant can operate for longer.

“What’s more, the software’s scripting capabil-ity is not restricted to time-based simulations,”

Gerald remarks in conclusion. “Various what-if calculations can also be performed and could be as simple as sizing an orifice plate to generate a specified pressure loss in a system.”

Gerald Holt, Holt Consulting Engineering, Tel: 079-894-9796, Email: [email protected]

Figure 3: Water Treatment Plant Demand = 50 l/s

FluidFlow3’s scripting can also perform a risk analysis of a pipe network system

www.skf.co.za



POWER GENERATION

Produced by:

PROMECH PUBLISHING,P O Box 373, Pinegowrie, 2123Republic of South AfricaTel: (011) 781-1401Fax: (011) 781-1403Email: [email protected]: www.promech.co.za

Managing Editor Susan CustersEditor Kowie HammanAdvertising Louise TaylorCirculation Catherine MacdivaDTP Zinobia Docrat/Yolanda Flowerday/Lilian Kemp

DisclaimerPROMECH Publishing does not take responsibility for the opinions expressed by individuals.

Printed by: Typo Colour PrintingTel: (011) 402-3468/9

CopyrightAll rights reserved. No edi-torial matter published in “Power Generation Today” may be reproduced in any form or language without written permission of the publishers. While every effort is made to ensure accurate reproduction, the editor, au-thors, publishers and their employees or agents shall not be responsible or in any way liable for any errors, omissions or inaccuracies in the publication, whether arising from negligence or otherwise or for any conse-quences arising therefrom. The inclusion or exclusion of any product does not mean that the publisher or editorial board advocates or rejects its use either generally or in any particular field or fields.

Mining Coal DifferentlySouth Africa is setting the pace in terms of utilising alternative energy sources

for the generation of electricity. The tried and tested technologies of CSP (concentrated solar power) and UCG (underground coal gasification) have been

tackled by many other countries to date, but usually on a small scale.

Eskom, however, is currently busy with two projects using both these technologies, but on a scale bigger than anyone else in the world has

tried so far. “SA Mechanical Engineer” has delved into CSP previously, but this time round we dig into underground coal gasifica-tion (UCG), a technology which first came to light nearly 150 years ago. We speak to Dr Mark van der Riet, corporate consultant on fuels at Eskom to find out how UCG will be utilised in South Africa.

Proven technology“There are different UCG technologies available in the world but we’ve chosen to licence the technology from the former Soviet Union where the process has been used since 1930,” he says.

“In the fifties they commercialised the pro-cess to run on 13 different sites, but all on a relatively small scale. We are looking at a demonstration cum research plant of over 100 MW which, if successful, will enable future UCG power generation plants.”

What is UCG?Underground coal gasification converts coal to gas while still in-situ in the coal seam under the ground. Gas is produced and extracted through wells drilled into the un-mined coal seam. Injection wells are used to supply the oxidants such as air, oxygen, or steam to ignite and fuel the underground

gasification process. Separate production wells are used to bring the product gas to the surface.

The high pressure gasification takes place at temperatures of 700–900 °C, but it may reach up to 1,500 °C, during which the process decomposes coal and gener-ates predominantly carbon dioxide (CO2), hydrogen (H2), carbon monoxide (CO), and methane (CH4).

Variety of designsIn addition, small quantities of various con-taminants including sulphur oxides (SOx), mono-nitrogen oxides (NOx), and hydrogen sulphide (H2S) are generated. As the coal

Underground coal gasification converts coal to gas while still in-situ in the coal seam under the ground

Dr Mark van der Riet, corporate consultant on fuels at Eskom


POWER GENERATION

face burns and the immediate area is depleted, the oxidants injected are controlled by the operator.

There are a variety of designs for underground coal gasification, all of which provide a means of inject-ing oxidant and possibly steam into the reaction zone. They also provide a path for production gases to flow in a controlled manner to surface. As coal varies considerably in its resistance to flow, depend-ing on its age, composition and geological history, the natural permeability of the coal to transport the gas is generally inadequate. For high pressure break-up of the coal, hydro-linking, electric-linkage, and reverse combustion linking may be used in varying degrees.

How it worksThe simplest design uses two vertical wells: one for injection and one for production. Sometimes it is necessary to establish a link between the two wells and here reverse combustion is often used to open internal pathways in the coal. Another alter-native is to drill a lateral well connecting the two vertical wells. In short, UCG is both an extraction process, like coal mining, and a conversion process, gasification, in one step, producing a high quality, affordable synthetic gas that can be processed to provide fuels for power generation, diesel fuels, jet fuels, hydrogen, fertilisers and chemical feedstock.

“Although you do away with the need for people

The miners now become drillers as they constantly sink a matrix of boreholes into the coal seam from above the ground

The gas treatment plant currently running near Majuba power station

Below this natural landscape a UCG mine is producing gas, one of the environmental advantages of the UCG technology

A basic illustration of how UCG works


and machinery to mine and process the coal as in conventional coal mining, roughly the same num-ber of people working on a conventional coal mine are used on a UCG plant above the ground,” says Mark. “It is a complex engineering process involving many people, not only in the gas cleaning processes above ground, but the miners now become drillers as they constantly sink a matrix of boreholes into the coal seam from above the ground.

Expanding cavity“These boreholes, or wells, are the same as those used widely for the exploration and prospecting of a variety of underground ore bodies,” explains Mark. “Where UCG starts to deviate from the con-ventional, is through the creation of sealed wells. A continuous steel casing is cemented in place into the well. A link is then created between adjacent wells through the coal seam, the coal is ignited, and air is pumped via the injection wells into the link.

“The coal is consumed, and in so doing creates an expanding cavity throughout the coal seam,” adds Mark. “Multiple cavities are formed in this way and the resulting gas is then blended into the final product. This sequence of operation forms the basis of the specific UCG mining technology which we’ve adopted and is the proprietary knowledge derived from the licence with our technology provider.”

Higher efficiencyThe underground cavity walls literally form the boundaries of an underground reactor which operate at high pressures and temperatures. “UCG has the potential to extract the energy bound within coal resources previously regarded as either uneconomi-cal or inaccessible due to depth, seam thickness, seam slope, seam fracturing and displacement, as well as for safety reasons,” explains Mark.

“A wide variety of coals are amenable to the UCG

process. Coal grades from lignite through to bitu-minous may be successfully gasified. However, a great many factors have to be taken into account in selecting appropriate locations for UCG, including surface conditions, hydrogeology, lithoglogy, coal quantity and quality.”

Tried and testedAt this stage, Eskom is pretty much up-to-speed on this technology. Last year, after many years of research and visits to existing UCG plants across

POWER GENERATION

So far modelling has indicated that there should be a reduction in unburnt carbon, nitrogen oxides and carbon monoxide

The gas plant with Majuba in the background

UCG plant and power station combination plan


POWER GENERATION

the world, Eskom’s first UCG pilot plant trialled delivery of gas to Unit 4 at Majuba Power Station where the gas was co-fired briefly with coal, contributing around 3 MW to the unit’s current electricity production of approximately 650 MW. “In the case of Majuba, six standard pulverised coal burners on Unit 4 have been modified with retractable gas lances to introduce the UCG gas,” explains Mark. “The gas introduction is fully integrated into the boiler control systems. The effects of co-firing will be researched by our team and compared with baseline data, but so far modelling has indicated that there should be a reduction in unburnt carbon, nitrogen oxides and carbon monoxide.”

Next phaseThe next phase of Eskom’s ongoing UCG development plan is currently being as-sembled for approval, pending the per-formance of the pilot plant and extensive studies to date.

ConsequencesOne of the frequently asked questions about this method of mining is what happens once the all the coal in the cavity has been depleted, will the surface ground cave in? “At Majuba, for example, the coal seam

is on average 300 metres underground while the coal seam is some 3 to 5 metres thick,” answers Mark. “The coal itself contains some 35% ash, which is incombustible material remaining behind after the UCG process is complete. The net result on the surface is moderate and gradual, literally just tens of centimetres and will only show on the surface over decades.”

It is clear that Mark and the UCG team have already learnt a lot about this technology in practice with the current project, but there’s probably as much still to be learnt in terms of scaling up. “The most important thing I’ve learnt is not to give up easily, especially when people say outright that it can’t be done,” Mark says with a wry smile. “Sometimes we tend to over-complicate things unnecessarily which is one of the reasons we’re doing thorough research on the next project, to simplify things.”

Dr Mark van der Riet, Eskom, Tel: (011) 629-5155, Email: [email protected]

The flare at the UCG plant

Engineer PlacementsProfessional opportunitiesOur job board continues to display a wide variety of excellent job positions that you can review and apply for online. Keep your credentials on our secure and confidentialdatabase,updatethematanytime.We keep in touch with you.

www.engineerplacements.com

www.gearing.co.za

www.engineerplacements.com



POWER GENERATION NEWS

Powering up Zimbabwe Consulting firm Hatch Africa has been selected by power utility, Zim-babwe Power Company (ZPC), to act as the lead consulting engineer on its Hwange Thermal Power Sta-tion Expansion Project, located in the Matabeleland North Province of Zimbabwe.

Hatch Africa director Marius Kno-esen says that the project involves the expansion of the Hwange Ther-mal Power Station to include ap-proximately two additional 300MW coal-fired plant units. As the lead consulting engineer on the project, Hatch Africa will be responsible for

outlining any design and engineering-related requirements. In addition, as the project will be carried out on an engi-neering, procurement and construction (EPC) basis, Hatch Africa will be responsible for procuring an EPC contractor, which they will then manage.

Hatch Africa technical specialist Eben Conradie points out that Zimbabwe’s current power demands call for approximately 2 000 MW of power; while currently there is a shortfall of 800 MW. The additional power provided by the Hwange project will add almost 30% to the country’s supply, thereby securing a reliable supply of power to the region which will in turn encourage development and investment in Zimbabwe.

Hatch Africa thermal energy manager (and project manager for Hwange Power Plant Extension Project) Jan Fourie says that the first phase of the project kicked off in March 2011, with the completion date of the second phase scheduled for late 2011 and commissioning towards the end of 2014. Hatch’s offices in South Africa will participate in the proj-ect, with input from their offices in Australia and Canada. In addition to Hatch’s input, the project is currently being

Marius Knoesen

run as an integrated team, with contribution and col-laboration from ZPC.

Meanwhile, in an effort to further develop and grow the engineering fraternity in Zimbabwe, the com-pany has signed a sub-consultancy agreement with a local group of engineering companies named the Zimbabwe Africa Infrastructure Development Group (ZAIDG), which will see the group acting as Hatch Africa’s local representative firm. The agreement will see Hatch supporting the ZAIDG in the development of engineering capability within Zimbabwe; whilst the ZAIDG will support Hatch with manpower and advise on local legislative requirements.

“We ultimately have a long-term vision to involve the ZAIDG in a number of the projects that Hatch Africa has secured in Zimbabwe. At the same time, the ZAIDG will bring in work for Hatch from the local

sector,” explains Marius.

In addition to the Hwange Thermal Power Station Expansion Project, Hatch Africa has also been selected as lead consulting engi-neer to extend the Kariba South hydroelectric power station. They manage and oversee the extension of the Kariba South hydroelecri-cal power station to include two additional 150MW units. The extension will increase the power station’s capacity from 750MW (6 x 125MW units) to 1050MW.

Rashree Maharaj, Hatch, Tel: 011 239-5300, Email: [email protected], Web: www.hatch.co.za

Waste-to-energy plantHoneywell has signed a contract with Fortum to deploy its Experion Process Knowledge System and Safety Manager emergency shutdown and boiler protection system at the company’s new waste-to-energy facility in Klaipeda, Lithuania.

All of Fortum’s production sub-systems – both Honeywell and non-Honeywell – will be integrated into the Experion Human Machine Interface. Klaipeda plant operators will be able to centrally monitor and control all plant processes. Safety Manager will help reduce the potential for human incidents and asset damage at the site.

The new power plant will be fuelled by municipal and industrial wastes as well as biofuels. The production capacity will be approximately 50 MW heat and 20 MW electricity. It’s expected there will be an increase in energy production efficiency. In addition, the CO2 emissions of the heat production in the area will reduce significantly.

The new power plant is expected to begin operation in the beginning of 2013.

Debbie Rae, Honeywell, Tel: 011 695-8000, [email protected]




NUCLEAR INSTITUTE (SA BRANCH)

John Walmsley

Two recent publications, both purporting to be written by environmentalists, come to very different conclusions concerning nuclear generation. The respectable one, ‘The God species – how the planet can

survive the age of humans’ is by Mark Lynas, a British environmentalist with impeccable former anti-nuclear activist credentials. This is an excellent book. In other words, it’s one with which I whole-heartedly agree.

Lynas is associated with a body he refers to as the ‘planetary boundaries expert group’. The group has defined nine inter-

related ‘planetary boundaries’ that we transgress at our global peril. Some are obvious, others less so.

There is space here to mention just some of them. The first concerns bio-diversity. Species are inter-dependent. Pull too many loose bricks from the wall and suddenly the whole structure collapses. To reduce the rate at which species are disappearing to just ten per million per year from the current

estimated 100 to 1000 per million per year we must create vastly more wilderness and wetlands – not less.

A thousand times betterA related boundary concerns land use. The group believes that we can use not more than 15% the Earth’s surface for cropland. The present figure is 12%. Biomass for fuel is out. Organic farming is too unproductive. We must genetically engineer varieties with higher yields and more efficient ni-trogen utilisation. There is also a nitrogen boundary related, inter alia, to nitrate pollution of the oceans. Urbanisation is to be encouraged. Mankind must give up land to wilderness. Nuclear, which does not emit greenhouse gases and which will therefore also help meet the climate change boundary (350 ppm only) is the most land-efficient power source, a thousand times better than biomass.

Environmental sacred cows are slaughtered left, right and centre. Linas has harsh words for environ-mentalist ‘Luddites’ who strive to keep them alive.

The cover of the second publication ‘The true cost of nuclear power in South Africa’ suggests that it is authored by Greenpeace. In fact, the small print shows otherwise. The authors are largely the small but vociferous group of local anti-nuclear activists. The arguments are therefore very familiar. The early chapters are a reiteration of South African nuclear history as presented in the anti-nuclear treatise

Environmentalists at Odds

(and film) ‘Uranium Road’ promoted by Earthlife Africa and aired several times by SABC. It is much concerned with the nuclear weapons programme conducted by the ‘apartheid regime’. The intention is to tar nuclear generation with the apartheid and weapons brushes.

Later chapters on safety are scurrilous. For ex-ample, the allegation is made yet again that over five hundred former workers at Pelindaba suffer from various forms of radiation-induced sickness and are unable to obtain compensation. In fact, several years ago, ELA went into Atteridgeville, asked if anyone who had worked at Pelindaba (over the last forty years) was now sick, and held out the hope of compensation for anyone who came forward. Not surprisingly, five hundred now elderly, sick and desperately impoverished ex-employees did so. NECSA was able to examine a few of them and twelve cases of noise-induced hearing loss have been submitted to the Compensation Commission. Most of the men affected evidently accepted ELA advice that NECSA doctors could not be trusted and failed to present themselves.

Blatant misrepresentationOne death at Pelindaba is mentioned in particular. The implication is that radiation was to blame. In fact, the cause was fluorine inhalation. A Koeberg employee who was found to have leukaemia is also named. The facts that his exposure to radiation was negligibly low and that the leukaemia was of a type not known to be caused by radiation are not mentioned. And so on.

What to do about such blatant misrepresentation? Eskom has in the past considered legal action – and decided not to go that way. It can reasonably be argued that legal action would merely open the door to yet more public posturing by ELA. So should this ‘Greenpeace’ publication also be allowed to pass unchallenged? Certainly there is nothing to be gained by confronting the authors.

On the other hand, if I were a female Minister of Energy with a background in social work, hard though that may be to imagine, I would want to be assured that nuclear management had reviewed the material and that there was no substance to it. Perhaps she does receive such assurance, sotto voce.

John Walmsley

Pull too many loose bricks from the wall and suddenly the whole structure collapses


PIPES, PUMPS & VALVES

Slurry SolutionBy nature slurry pumps need regular maintenance because they usually transport highly abrasive materials which wear

away the protective liners, seals and throatbushes while also affecting bearing life.

W ith wear characteristics in mind, Weir Minerals has developed two new slurry pump models, not only to reduce wear, but also

to make the changing of liners and efficiency adjustments on the pump easier than ever before for the pump user. “SA Mechanical Engineer” speaks to Rui Gomes, product manager for slurry pumps at Weir Minerals Africa.

Medium duty“From many years of experience in slurry pump design we’ve recognised the need for a medium duty slurry pump, paving the way for the new Warman SLR pump which we now manufacture locally,” he says. “The SLR series has been designed for slurry handling duties in the mining and chemical industries where the use of a very heavy duty slurry pump cannot be justified.

The pumps are rubber-lined and are favoured by the gold, platinum and chrome processing industries because of the extended wear life that they offer.”

Although the design focus remains around address-ing wear, there are some interesting new features. “One which stands out is the pump housing which splits axially into a top and bottom part as opposed to the usual front and back part assembly you see with conventional slurry pump housings,” says Rui. “The reason for this is to make maintenance easier. You simply take the top half off to gain access to the volute for replacing the one-piece rubber liner.

Features“Apart from this one-piece volute liner being a unique new feature, especially in slurry pumps, we’ve addressed the profile of this liner in order to beef up the areas where wear is usually excessive. Also, from a cost perspective, a one-piece liner is more economical and easier to fit and line up than two separate pieces.”

In any pump, it’s all about the impeller design. “We’ve revised the hydraulic profile of the vanes on the impeller in order to increase efficiency,” explains Rui. “Although the benefits are nominal, between 1 to 2 %, every little bit counts to improve the overall efficiency of the pump. The more efficient the pump, the less power it consumes.

Unique system“The most unique feature on the new design, however, is something which is likely to become a standard in time to come,” says Rui. “Our new throatbush is fully adjustable. For a pump to run at optimum efficiency all the time, the gap between the throatbush and the impeller has to be kept to an absolute minimum to avoid recirculation which leads to excessive wear, meaning it has to be adjusted every now and then as the throatbush wears away.”

You simply take the top half off to gain access to the volute for replacing the one-piece rubber liner

Rui Gomes, product manager slurry pumps at Weir Minerals Africa

The first Warman SLR pump to be installed in South Africa



“We’ve done away with this feature altogether,” ex-plains Rui. “We now have a fixed bearing assembly with an adjustable system with four pusher-bolts on the front of the pump which can be adjusted in situ from outside the pump without having to dismantle it. This system simply pushes the throat-bush closer to the impeller as it wears away over time, constantly keeping the gap to the absolute minimum. This means that the pump is running at its ideal efficiency for much longer, thus reducing the power requirements of the pump.

“Because of this ground-breaking technology, we no longer need an adjustable shaft, hence this pump has a fixed bearing assembly,” adds Rui. “Because the bearings are fixed, we certainly expect longer bearing life as well. In addition, in terms of the bearing assembly itself, we’ve addressed the sealing arrangement in order to reduce the chances of any ingress of dirt or water into the bearing assembly. Seals are, therefore, now integrated as part of the fixed bearing assembly”.

Heavy dutyThe other new product on the South African market, which is also manufactured locally, is a heavy duty slurry pump which has been developed over the past four years by Weir Minerals’ design centres of origins (DCO) across the world who’ve provided

The pump is running at its ideal efficiency for much longer, thus reducing the power requirements of the pump

A side view of the new Warman WBH 150 slurry pump

Conventionally this gap is corrected by means of the adjustment made to the bearing assembly shaft.

www.atlascopco.co.za


ongoing input and feedback. “The global launch was a couple of months ago, but we fast-tracked local manufacture of this brand-new design to offer it here as well,” says Rui. “Apart from generally optimising all features of the WBH centrifugal slurry pump, this design is interchangeable with rubber or metal liners providing a much wider range of applications across more industries.

“ We have made vast improvements to the hydrau-lic design in terms of both liner profiles and the impeller design,” adds Rui. “In terms of the fixed bearing assembly it is very similar to the SLR de-sign, but we’ve opted for a larger diameter shaft to reduce deflection which has proved in the past to have a direct effect on bearing life. Adjustment of the throatbush is also featured, but on this model we’re using a single point of contact bolt to adjust the throatbush closer to the impeller as it wears. In addition, this adjustment mechanism rotates the throatbush in order to spread the wear of the throatbush more evenly. The bolt is located on the outside of the casing before going into a geared arrangement which simultaneously rotates the throatbush as it is adjusted closer to the impeller.

“The benefits of both these new designs are not only power saving due to better pump efficiency, but also longer pump life as the pumps run more

Miro Potparic, general manager Weir Minerals Africa Alrode, and Rui Gomes, slurry pump product manager Weir Minerals Africa, viewing the new Warman WBH slurry pump produced at the Alrode manufacturing site


efficiently for longer periods of time,” concludes Rui. “Cumbersome maintenance has been reduced substantially which should contribute to far better efficiencies than ever before, above and above a much longer pump life.”

Rui Gomes, Weir Mineral, Tel: (011) 929-2805, Email: [email protected]

www.hansenindustrialgearboxes.co.za



SAINT

rust) colour. The damage could be local or general. Localised corrosion could be a deep pit or a few corrosion pits in isolated areas and often happens where a breakdown of a coating traps moisture. General corrosion normally happens when no coat-ing was present and could be a large pitted surface or could be a smooth loss of thickness that cannot be easily seen without the aid of a straight edge.

How can it be detected?The surface is exposed to the atmosphere and a loss of thickness can be seen visually. A build up of corrosion product (scale) may be present. A straight-edge placed over the surface may be necessary to see the effect of smooth atmospheric corrosion and an ultrasonic thickness measurement should always be done in the suspected area.

Areas where it is foundA presence of moisture in the atmosphere is the main factor and atmospheric corrosion may be pre-dicted simply by the location of the object. Marine and industrial environments are the most corrosive. Chemicals like salt and sulphur in the industrial atmosphere will accelerate the rate of corrosion. A moisture drift on the wind from cooling towers and even shaded areas where the sun does not readily dry away moisture may affect objects. Areas where water stands for longer than normal will be more corroded. Corrosion increases with temperature, however above 120 degrees C the surface is usu-ally too dry for corrosion to take place.

Can it be avoided?Design equipment to ensure proper drainage. Prop-erly prepared surfaces and correctly apply quality coating. Inspect coatings regularly. Repair damaged coatings. Excess corrosion product build-up should be removed with care when the object is under pressure. Reduce the pressure for safety.

Robin Marshall, Tel: 011 719-5717, Fax: 086 582 8509, Email: [email protected]

Conferred Honorary Doctorate“As Vice-Chancellor and Principal of the Vaal University of Technol-ogy, I am extremely pleased to inform you that the submissions of your name by the Honorary Degrees Committee to the Senate and Council of the University have Manfred Siegfried Johannes been accepted and approved”.

An Honorary Doctorate in the field of Non-Destructive Testing (Faculty of Applied and Computer Sciences) was conferred on by the Vaal University of Technology on 13 September 2011 at the Vanderbi-jlpark campus. This prestigious doctorate was awarded to Manfred in recognition of his sustained contribution to the Non-Destructive Testing and Physics Department of the Vaal University of Technology.

As a Chief mem-ber of the Exter-nal Review Panel for Non-Destruc-tive Testing and member of the Non-Destructive Testing Advisory Board, Manfred has provided the university with precious counsel and assistance as they upgraded fa-

cilities for Non-Destructive Testing at VUT. In addition, the many NDT workshops that he conducted over the years have been invaluable in lifting the profile of this discipline within the university.

How is it recognised?Atmospheric corrosion forms on the external of an object that is exposed to the atmosphere and has a distinctive iron oxide (red

Atmospheric CorrosionCorrosion occurs due to moisture associated with atmospheric conditions in carbon steels, low alloy steels and can also affect copper alloyed aluminium.




a direct presence in Africa by opening an office in Honeydew north of Johannesburg. “SA Mechanical Engineer” speaks to international sales manager,

Tyron Adam. “Although the company has been around for over five decades, these pumps have only been available in South Africa through distributors until about two years ago,” he says. “Now that we’ve established an office here to actively market the product, we regularly come across applications where the wrong pump is being used, particularly in the pulp and paper industry.”

A progressive cavity pump is a type of posi-tive displacement pump. Also known as an eccentric screw pump or even just a cavity pump, it transfers fluid by means of the progress through the pump of a sequence of small, fixed shape, discrete cavities as its rotor is turned. This leads to the volumetric flow rate being proportional to the rotation rate while a low level of shearing is applied to the pumped fluid. Hence these pumps are applied in fluid metering and the pump-ing of viscous or shear sensitive materials.

SavingsPump selection is critical, not only in terms of the size of the pump, but also in terms of

Special Pumps For Special Duties

There was a time when South Africans had to make do with what they had available, so they used ‘improper’ machinery

for an application. As the machinery worked fairly well and as the decades passed, it became acceptable practice with nobody bothering to question the authenticity of its

application.

This is often the case in pump applications. But today’s market is characterised by specialised pump technologies and pump designs to cater for the moving of a wide

range of materials in its various forms, from clear water to thick sludge containing fibrous solids and aggressive chemicals. Today there is a specialised pump for each application, making pump selection a critical factor in obtaining optimum efficiency.

Local presenceNetzsch, a German company which specialises in progressive cavity type pumps, has now established

Today there is a specialised pump for each application, making pump selection a critical factor

Tyron Adam, international sales manager at Netzsch Southern Africa

The inner workings of the Tornado rotary pump



The Tornado rotary lobe pump

choosing the right type of pump technology. “We have a special pump particularly suitable for moving bagasse, for example,” explains Tyron. “At a paper mill where they use bagasse, we recently found that they were using the wrong pump technology altogether. It was costing around R400 000 per repair and they were doing two repairs a year. We sold them a pump that did not even come close to their maintenance costs per year. In addition, our dedicated pump only needs maintenance repairs every ten months at a fraction of what they spent on maintenance before.”

Immediate benefitsThis is just one example, but Tyron says it’s common in many other industries. “It’s a harder sell though,” he adds. “Engineers have been subjected to poor performing equipment without having the option of an superior alternative and then you pitch up to tell them they’ve been doing it all wrong. However, once they see the difference and the savings that can be achieved, they usually buy in.

“The benefits of using the right products for the right job are immediate but there’s also the energy consumption consideration,” adds Tyron. “At a paper mill, for example, they usually move the pulp with

medium consistency pumps which are vacuum assisted to prevent

the pump from developing cavitations. Our pumps, on the other hand, can easily pump solid content up to

16% which is about double that of the medium consis-tency pumps usually used. Therefore, using our pumps

mean that the evaporators, where the pulp is eventually dried

out, don’t have to work so hard, saving on the overall energy con-

sumption of the plant. Power savings

on pulp applications is not just on evaporators, but the pump itself uses 60% less power than a centrifugal pump.”

ModularNetzsch’s Nemo pumps are modular in design with all four pump geometries having the same outer dimensions. “Apart from the rotor and stator, all other components are identical,” explains Tyron. “When a change in flow rate or pressure is required, installed pumps can be adapted to the new operat-ing conditions by simply changing rotor and stator.”

One of the most versatile pumps to mention, out of their huge range of other specialised pump configurations, is the Netzsch Tornado positive displacement, self-priming, valveless pump. “This pump offers high performance and is selected and

configured for the individual requirements of each application,” says Tyron. “They are designed for intermittent or continuous operation and provide gentle pumping of the pumped media making them ideally suited to transfer, process and dosing applications.

Making headway“This includes liquids which contain large solids up to 70 mm in diameter,” adds Tyron. “They can handle liquids within a wide range of viscosities, from 1 mPas up to 1 million mPas including ma-terials which are shear sensitive, as in thixotropic, dilatant, pseudoplastic and so on. They are ideal for fibrous and abrasive media. What makes this pump even more versatile is the fact that rotors in different geometries and materials can be selected for the individual requirements of the product to be pumped.

“Internationally the company has long since estab-lished itself as a world leader in terms of progressive cavity type pumps as well as RLP (Rotary Lobe) and offer both to bring clients the best solution for an application, but we’re only now making headway into Africa,” Tyron remarks in conclusion. “We have a lot to offer the local market based on worldwide experience in the application of these pumps. Tyron Adam, Netzsch Southern Africa, Tel: (011) 794-8975, Email: [email protected]

Our pumps can easily pump solid content up to 16% which is about double that of the medium consistency pumps

Netzsch pump in an oil & gas application




SAIT

A ‘Friction Fest’‘After gravity, tribology is the second most important property of matter; it is a complex science that

impacts every person in almost every situation, and has a tremendous effect on industry at large, from energy consumption and wear in the largest machines to the joints in our bodies. Tribology is the study of friction and wear. Without friction the world as we know it would not exist: we would all slide around endlessly’ – from ‘SA Tribology Project 2010’, a paper presented at the recent international conference.

What happens at an international event, such as the recent 10th SA Institute of Tribology (SAIT) 2011 International Conference, is an exposure of friction

and wear by an impressive guest list of luminaries who are passionate tribologists, meaning everything to do with friction and wear and nothing to do with human tribes. Ranging from the tiny nano- and micro-particle studies, through to the large – micro-dosing – and the massive – Eskom power station condensers – there’s no holy territory that a serious tribologist will not examine to minimise wear and reduce friction. That was the range of presentations that the SAIT dealt with at host venue Pretoria University from the 5-7 April 2011.

Today and growing in fashion, ‘Green’ is the word. And tribology is all about being green. After all we do need measured friction to brake the world’s ve-hicle population – forecast to hit 1,2 billion (that’s right, billion is the word) by 2020. The outcomes of this forecast from Forrester Research are fairly axiomatic and tribology can play a significant role in meeting these challenges:

• Theworld'svehiclepopulationisexpected to double in next 15 years

• Thiswillcauseseveralproblemsforresources and environment

• Theoilsupplywon'tbeenoughtosatisfydemand

• Trafficinjuriesanddeathswillescalate

• Scrapmetalretirementwillbecomeamajor problem

• Chinawillbetheengineofmuchautoindustry growth

But to smooth that path where energy is required to move forward, there’s a ‘green’ function for tri-bology, and that was the keynote message to the SAIT conference from Prof. H Peter Jost, the man who gave birth to the word ‘Tribology’.

And if you are not aware of it, there is a Tribology Chair at Pretoria University under the guidance of Prof. P L de Vaal. A tour of the University’s facilities was undertaken following a paper presented by the University of Pretoria; The Tribology Laboratory at UP - Collaboration between Academia & Industry.

A copy of this paper is available from the SAIT. While South Africa has recently suffered a flight of intellectual capital it’s good to know that we do have a centre for this specialist knowledge and that industry has the opportunity to move out of its arrogant shell and talk to academia.

A summary paper of a 2010 SAIT study was pre-sented at the conference. Sponsored by the South African Department of Science and Technology, and titled ‘SA Tribology Project 2010’ the study/report objective was to determine the cost and energy saving potential of tribology to South Africa. One serious aspect that emerges from this study is the really concerning state of lubrication practices in South Africa.

Here are a few key findings affecting every aspect of industry, mining, agriculture and transport in South Africa today:

Root-cause failure analysis is not typically performed in industry hence the true value of lubrication related failures cannot be determined. There are however a number of individual operations that are conducting root cause analyses and have reliability engineers for failures above a certain value. Most failures and breakdowns that occur are typically due to:

• Contamination,waterordirtingress

• Alignment

• Poormaintenance

• Lackofgreasing/lubricating

• Policiesandcontrol

New tribological terms for your use:

Nanotribology – the study of friction and wear processes on the nanometer scale; the engineering of matter at a scale approaching that of

individual atoms.

Teratribology – movement of plates on which the

continents rest.


The major component failures are gearboxes, pumps and bearings.

Typically up to 35% of the failures are caused by shaft misalignment. Laser alignment equipment is normally available, but is not always used by the maintenance personal, unless the reliability department insists and checks that this occurs.

An example in one plant was fans with double spherical bearings that were failing: 30% were due to misalignment and 70% due to balancing. Bearing life in the 18 fans was 2-3 months. With correct alignment and balancing this was reduced to ap-proximately one failure per annum. These failures indicate the lack of skills, attitudes and training of artisans and artisan helpers. It is believed that this could be the cause of up to 60 -70% of all failures.

This study has shown that, in general, equipment life has been reduced by a factor of three over the past 15 to 20 years. The loss of equipment life is a lack of traditional maintenance skills. ‘Modern’ maintenance has forgotten that dirt does not lu-bricate, that shafts must be correctly aligned and that oils and greases are not all the same. The report goes on to point out the desperate need to get back-to-basics:

• Aneedtocalculatethecorrectviscositygrades throughout to minimise energy wastage

• Tounderstandthedifferencebetweengradeand type of lubricant

Education is a priority, from the boardroom to artisan level. Tribology is currently only taken as a research subject by Post Graduate students. A lubricator is one of the most important persons on the plant, and must be trained and recognised accordingly.

Here are three items for policy-makers –

• Totalcostofownershipofassetsshouldbea philosophy that is implemented

• FiltersandfiltermanagementisCRITICALin improving system cleanliness and improving component life

• Designofsystemsfromanoperationandmai tenance perspective is essential to minimise dirt contamination of systems during maintenance

Tribology must have a strategic and not just op-erational value!

It’s a tragedy that lubrication is perceived to have no strategic value. It’s all compounded by lubrica-tion costs that are such a small part of operating expenses and applied by the most unskilled labour available (‘grease monkeys’). Management only notices lubrication and unnecessary friction when the ‘wheels stop or fall off ’ productive plant and machinery.

Weak lubrication practice has a severe impact on machinery life, productivity and operating costs, which means it’s time to make lubrication a strategic and policy-driven issue.

The 21-page paper on the ‘Tribology 2010’ report is broad-brush stuff but worth the read and available FOC – Free of Charge! It might change your mind about how we think about friction. But importantly, make friction (rather tribology – your new word) a strategic issue – this elevates the subject to the level of being policy-driven, environmentally-friendly, energy-conservative and concerned with life-cycle costs.

This SAIT ‘friction fest’ is a well-organised and documented event. There’s the usual range of pre-senters from those that make post-lunch drowsiness an even worse drag, to the enthusiasm of others who get your personal and physical tribological aspects pumping. The material ranges from the very esoteric to absolutely practical with an overall approach that is very objective. Site visits are also included on the agenda and a visit to a thermal spraying plant was a real eye-opener – it’s good to know this type technology still exists in South Africa when we seem to spend all our resources on stadiums and casinos while importing everything from China.

Three days of intellectual output is too vast to condense into one short overview. If you are really serious about being ‘green’, have a lubrication or friction problem and want to pursue a solution, then direct yourself to the SA Institute of Tribology. Papers from the International Conference are available and the SAIT will be happy to assist your enquiry.

References & acknowledgement: Swan PG, Fitton JC; South African Institute of Tribology; SA Tribology Project 2010’A copy of this paper can be obtained from the S A Institute of TribologyReport by Dave Scott - SAIT Member

The SAIT will once again be hosting the highly-regarded STLE CLS exam on the 18th November 2011 at Science Park. For those of you who are unfamiliar with this arrangement, the SAIT is affiliated with the US-based Society of Tribologists and Lubrication Engineers (STLE) who created and administer the Certified Lubrication Specialist (CLS) qualification. It is a broad-based lubrication and tribology qualification, designed to test and acknowledge an individual’s knowledge and expertise in these fields. Over the last decade a number of SAIT members have successfully tackled this tough exam, and benefited from the recognition provided by this qualification. As in previous years, the SAIT will be running a two-day preparation (not training) course leading up to the exam. The course will be held at Science Park on the 16th and 17th November and will be facilitated by a current STLE CLS graduate. As 7 of the 10 places available on this course have already been filled, make sure you guarantee your place by booking as soon as possible. Contact Gill or Isabel at the SAIT ([email protected] ).

For further information about the STLE and the CLS, visit the website www.stle.org.

SAIT

www.sait.org.za


SAPMA

Pimp My PumpThis monthly column, submitted by SAPMA (SA Pump Manufacturers Association) guides and advises readers

on the in’s and outs of the pump world.

Pumps connected in parallel are often used when:

•therequiredflowishigherthanonesinglepump can supply

•thesystemhasvariableflowrequirementsandwhen these requirements are met by switching the parallel-connected pumps on and off.

Normally, pumps connected in parallel are of similar type and size. However, the pumps can be of different size, or one or several pumps can be speed-controlled and thereby have different performance curves.

To avoid bypass circulation in pumps which are not running, a non-return valve is connected in series with each of the pumps. The resulting performance curve for a system consisting of several pumps in parallel is determined by adding the flow, which the pumps deliver at a specific head.

Figure 1 shows a system with two identical pumps connected in parallel. The system’s total perfor-mance curve is determined by adding Q1 and Q2 for every value of head which is the same for both pumps, H1=H2.

Because the pumps are identical the resulting pump curve has the same maximum head Hmax but

Fig 1: Two pumps connected in parallel with similar performance curves

the maximum flow Qmax is twice as big. For each value of head the flow is the double as for a single pump in operation:

Q = Q1 + Q2 = 2 Q1 = 2 Q2

Figure 2 shows two different sized pumps connected in parallel. When adding Q1 and Q2 for a given head H1+H2, the resulting performance curve is defined. The hatched area in figure 2 shows that P1 is the only pump to supply in that specific area, because it has a higher maximum head than P2.

Fig 2: Two pumps connected in parallel with unequal performance curves

Fiona Knell, Tel: 072 889 2789, Email: [email protected], www.sapma-sa.co.za



Market ForumAdvanced dissolving technologyMaterials processing technology pioneer, Eirich, locally represented by Birkenmayer, brings cost and energy savings to the South African material processing market with the latest dissolving and dispersing expertise of the Eirich Mixer.

“High energy input from the Eirich Mixer leads to short processing times when compared with other systems, and is therefore more economical. With its unique mixing prin-ciple, higher densities per litre are achievable and high tool speeds can be reached.

This allows for agglomerates to be disintegrated perfectly, solids to be dissolved or dispersed completely, and for primary particles to be completely coated with organic solvent films – without areas of low flow and with mini-mum space requirements,” explains Birkenmayer business development manager Louis Eksteen. “Eirich Evactherm mixing technology enables the creation of a vacuum for

slurry degasification inside the mixer.”

The mixer features Eirich’s unique mixing principle which combines rotating pans for material transport, with variable-speed mixing tools – enabling slow-to-fast-to-slow pan rotation for mixing, kneading, dissolving and dispersing. The distinction between material transport and the mixing process allows the speed of the mixing tool (and thus the power input into the mix) to be varied within wide limits – saving time on dissolving and dispersing tasks, while largely reducing energy requirements.

An ideal application is the ceramic industry, as it effectively disperses filter cakes, prepares clay, kaolin etc. “Spray slurry for sanitary ceramics, utility ceramics and technical ceramics can also be processed,” says Louis. The mixer is also great for the dispersement of plaster wastes, green scrap and cre-ating bodies for ceramic filters, besides other applications.

Birkenmayer, Louis Eksteen, Tel: (011) 970-3880-8, Email: [email protected], www.birkenmayer.co.za

The Eirich mixer with dissolving technology

Punching above its weight“As the new kids on the block, we are growing steadily and getting work from existing and new clients,” says Mining Pressure Systems (MPS) Projects director Michael Neves. Launched in 2007 as a project division of the MPS Group, MPS Projects is a solutions-provider to mining, construction and other industries across Southern Africa.

At present, the division serves the mining, petrochemicals, paper and pulp, sugar and power generation sectors. Initially specialis-ing in the erection of carbon steel, stainless steel, HDPE and rubber lined pipework, they’ve extended operations to include the installation of steelwork, platework and mechanical equipment. In addition to assisting the division’s core clients on existing projects, 2011 will also see MPS Projects focusing on a number of projects in sub-Saharan Africa.

The division has further refined the perfor-mance capabilities of its mobile autoclave, which is able to streamline the process of on-site rubber lining and insulation. “We have renewed our efforts in marketing this high-performance machine to African markets, which often have projects that are fairly isolated,” he says. “We can offer our clients on-site steam-cured rubber lin-ing for pipes up to 10 m to the same high



Market Forum

Spiral vs rectangular ductingWhy choose spiral ducting over rectangular ducting? Spiral ducting is manufactured in a highly automated system in specific sizes, ensuring prompt production and delivery, whereas rectangular ducting is always ordered in custom sizes increasing lead time. Not only does spiral ducting weigh less than rectangular ducting, the shape also has less surface area, saving on the cost of insulation material as well as the labour involved when insulation is required.

It can also be manufactured in longer continuous lengths than rectangular ducting thus reducing the cost of joint- and hanging material as well as labour cost. Contrary to popular belief, the space required for spiral ducting installation is

Spiral ducting

Air motor range to benefit SA industrial marketDowson and Dobson Industrial is increasing their product range in the company’s recently established assembly technol-ogy division, dedicated to the German-based Deprag brand.

Director Terry O’Kelly says the range conforms to Atex and is safe for use in potentially explosive environments. “The entire range is insensitive to potential hazards such as acids, dust, heat and vibration. What’s more, the advanced design ensures that all Deprag air motors are light and compact – at only 20% of the weight and 30% of the size of an electric motor of equivalent power, thereby saving clients significantly on floor space,” he adds.

The Basic line model has a patented vane exchange system providing production time savings, is best-suited for non-critical production environments and is available in power ranges of 200 W, 400 W and 600 W. Advanced line motors are 100% sealed, oil-free, non-corrosive and manufactured from stainless steel. They are particularly suitable for the paper and food processing industries and available in power ranges of between 20 W to 1,2 kW. The Power line range of-fers significantly higher starting torque with low performance weight, compared with an industry-standard electric drive. With robust and reliable design, and a power range of 1,6 to 18 kW, the range is ideally-suited to heavy industrial indus-tries such as refineries, rock drilling equipment and more.

Dowson and Dobson, Terry O’Kelly, Tel: (011) 392-2367, Email: [email protected]

standards that can be done at our Johannesburg workshop.”

This innovative on-site process reduces costs, eliminates time constraints, cross-border implications and gives a client total traceability to a key factor in a piping project. Moreover, MPS Projects has improved the standards of its mobile camps. “This can give a project a unique advantage as we are in an ideal position to establish a fully self-sufficient camp almost immediately,” he says.

MPS Projects, Tel :(011) 918-4750, Email: [email protected], www.miningpressure.co.za

often less than with rectangular ducting. Spiral ducting has a lower air leakage factor than rectangular ducting; when air leakages occur the fans and other equipment must work harder to compensate for this loss, resulting in higher run-ning costs.

The acoustic performance of spiral ducts is superior because the curved surface allows less breakout noise. Air measur-ing is also easier on spiral ducts, simplifying the balancing of the air distribution system. Finally, the cleaning methods for spiral ducting are less expensive and more effective than with rectangular ducting. Not only do Spiral ducts perform better, they also look better.

Airconduct, Sanet van Broekhuizen, Tel: (012) 804-0626, Email: [email protected], www.airconduct.com

Deprag air motor





Environmental compliance to cost billions lessRefineries will not have to spend tens of mil-lions of Rands modifying or replacing older API 610 Editions 5, 6, 7 and 8 pumps to comply with industrial emissions legislation.

This is according to Aesseal MD Rob Waites, who says that plant managers can comply by fitting these pumps with the latest, API 682 Edition 3 Category 2 and 3 qualification-tested seal technology sup-plied by his company.

Thousands of pumps installed in local refineries during the 1970s and 1980s are set to benefit. Rob says refineries can either change or modify every older pump in the refinery to meet the requirements of API 610 and API 682 spatial envelopes, or they can save millions and use the Aesseal upgrade, which fits older edition pumps without them needing modifications.

“Today, API 610 Edition Ten – the premium standard for the design and construction of centrifugal pumps in a petrochemi-cals environment – dictates a seal chamber with large radial clearance to accommodate hydraulically balanced cartridge mechanical seals, which are more robust and last longer.

The Aesseal Capi (Cartridge API) mechanical seals range, both pusher and bellows, was designed with specific consideration for both new and old equipment and is fully compliant with the specifications of API 682. “The range has the same qualified seal face technology for API 610 Edition Ten pumps as well as the API 610 Edition Five pumps, and all the pump variants in between, spanning more than four decades. All the older pumps in refineries across South Africa can be retrofitted, saving millions.”

Aesseal, Rob Waites, Tel: (011) 466-6500, Email: [email protected]

Aesseal Capi mechanical seal

Market Forum

Rob Waites

New sole agency agreementFesto South Africa has signed a sole agency agreement with GSR Ventiltechnik GmbH & Co, which gives them sole distributorship of GSR products for the South-ern African Development Community (SADC), East African Community (EAC) and Indian Ocean Isles.

The partnership with GSR Ventiltechnik will add solenoid valves and pressure control valves to the portfolio of process automation products. As part of this

www.festo.co.za

[email protected]


Market Forum

2012 PreviewSolidWorks 2012 includes many enhancements and im-provements, most in direct response to customer requests.

This release focuses on the following themes: automated functionality used most often; improvements in performance and quality that speed up software operation and create a more continuous workflow; new tools that greatly extend cur-rent SolidWorks design capabilities and enable fundamental

expansion, Festo will be adding additional stock capacity into its main stores in Johannesburg, as well as its branches across South Africa.

Comprehensive training is planned for authorised dealers and local staff to provide solid support to the GSR Ventiltechnik product range on offer. As the GSR Ventiltechnik solenoid valve range is substantial, the core range available locally through Festo will therefore include those mod-els tested in the global market. These include pilot-operated, force pilot-operated and direct acting valves, as well as pressure control valves, such as the angle seat valve.

Festo and GSR Ventiltechnik are committed to offer process automation customers a reli-able and fit-for-purpose installation, increas-ing productivity and efficiency. Festo Process automation manager, Brandon Skinner main-tains that the combination of Festo and GSR Ventiltechnik expertise will be of great value to the local market.

Festo, Tracey Swart, Tel: (011) 971 -560,Email: [email protected] www.festo.co.za

GSR Ventiltechnik MD Wolfgang Heil and Festo South Africa MD Richard Teagle

Cost-effective force measurementMeasurement technology specialist HBM is introducing strain transducers with integrated electronics for simple and cost-effective measurement of forces to the market. The SLB700A/06VA-1/2 transducer models work with strain gages and have an integrated ampli-fier, outputting measured values via an analog output with 0 to 10 V or 4 to 20 mA.

The strain transducers work in the force shunt and can be easily attached with four screws to the component whose loading is to be determined. A force that acts on a com-ponent leads to a strain that is transfered to and measured by the strain transducer. The amplifier integrated in the transducer ensures that the force measurement can be easily set up and implemented.

The amplifier is set up for this purpose with a so-called Teach-In method via a control contact. All that needs to be done is to approach the zero position and the maximum loading, then set the corre-sponding control impulses. This sets the amplifier so that the output signal is maximum and the resolution is always optimal. The amplifier has a limit frequency of 1 000 Hz so that this strain transducer is also suitable for dynamic measurements.

They are suitable for diverse applications, ranging from measurements in wind power plants and monitoring of build-ings to applications in production systems such as presses, welding units or injection molding machines. Passive HBM strain transducer SLB700 users can replace it with the new

The new SLB700A/06VA-1/2 strain transducer models have an integrated amplifier, making force measurements on components in force shunts easy

active strain transducer with integrated electronics as both versions are mechanically compatible.

Esteq, Elton Murison, Tel: (012) 809-9500, Email: [email protected]




Market Forumchanges in the product development process, as well as extensive support for collaboration and connectivity that al-lows design teams to work on joint projects across the globe.

Enhancements to functionality include automatic determina-tion of the proper solve order of equations to avoid circular references and reduce equation troubleshooting; automatic solving of cases that previously required multiple rebuilds, and an automatic rebuild option, to display graphically the impact of each change to equations.

SolidWorks provides a completely redesigned dialog box for creating and editing equations, global variables and dimensions. This release contains a host of new options that improve the workflow and efficiency for building and managing equations. Now all tasks related to equations can be performed in one dialog box without needing to open ad-ditional windows. Equations and global variables can also be created directly in the Modify dialog box for dimensions.

Mecad Systems Gauteng, Freek van den Berg, Tel: 086 111-2236, Email: [email protected], www.mecad.co.za

complements the ‘Workplace’ all-in-one compressed air system, reduces air leakage by operating at lower working pressure and perfectly matches capacity to air demand,” he says. These features deliver energy savings of up to 35%, reduce costs and shrink a company’s carbon footprint.

The compressor features Elektronikon control, an advanced control, monitoring and communication system, which fur-ther maximises overall compressor efficiency and reliability, minimising maintenance costs. All worldwide interfaces for remote control and communication are available.

Standard options on the series include an integrated dryer, combating moisture, dirt particles and aerosols in plant air. Atlas Copco’s development of compatible equipment enhances the quality and reliability of the system, benefiting a broad spectrum of applications.

‘Workplace’ systems require no compressor room, minimal floor space, and single point connection for and monitoring of power supply of compressors and ancillaries. Running costs are kept to a minimum as no piping is required to connect ancillaries to the point of use and highest extend, eliminating cumbersome and costly pipe network maintenance.

Atlas Copco South Africa, Tel: (011) 821-9000, www.atlascopco.co.za

Workplace compressed air systems The Workplace GA Series from Atlas Copco are ‘all-in-one’ compact, stationary compressed air systems that can be conveniently placed anywhere on the factory floor to meet clean air requirements.

“A combination of distinguishing features and benefits, including extremely low noise levels, allow the system to operate conveniently and cost effectively at point-of-use, making a conventional compressor room obsolete,” explains Atlas Copco Industrial Air Division business line manager, Philip Herselman.

“Our GA VSD (Variable Speed Drive) compressor, which

Local agent appointed for HVAC systemsActom Mechanical Equipment has been appointed the sole agent in Southern Africa for its main international techno-logical principal, Fläkt Woods’ modular heating, ventilation and air-conditioning (HVAC) systems.

“The agency agreement with Fläkt Woods’ Climate Control division is for their air handling units for HVAC applica-tions,” says Actom Mechanical Equipment product manager HVAC, Nuno Pereira. The Fläkt Woods modular air-handling units offer significant advantages over the traditional HVAC technologies by enabling quick and easy assembly and in-terchangeability of the various components – consisting of a fan, filters, silencer, humidifier and heat recovery system. They are also highly heat- and energy-efficient and hygienic.

Among their various features are an advanced energy-efficient heat recovery system, direct-drive plug fans, and electronically commutated motors, to ensure more accurate and speedier responsiveness. “85% of the life-cycle cost of an air-handling unit is energy, so the gains offered by the Fläkt Woods system are massive,” says Nuno.

Actom Mechanical Equipment and Fläkt Woods’ Climate Control division have already landed their first local contract – the supply of 60 air-handling units for the University of Botswana’s 450-bed new Academic Hospital, currently under construction in Gaborone, Botswana, for which deliveries will start later this year and complete in February next year.

The design required a product that would combine high levels of energy recovery in 100% outdoor air systems, which serve


www.atlascopco.co.za


Market Forummost areas of the hospital. This was met by the predominant use of the innovative Econet system.

Nuno Pereira, ACTOM Mechanical Equipment, Tel (011) 871-6789, Fax (011) 871-6677, Email: [email protected]

New Durban officeJohannesburg-based Monitor Engineering, sole importers of Spraying Systems Co’s range of spray nozzles, spray controllers and custom spray systems, has opened an office in Durban and will no longer be solely working through agents in the KZN region.

Due to the changing nature of the company’s extensive product range from supplying just spray nozzles to sophisti-cated precision spraying equipment, it was felt that expert application assistance and product knowledge is required to assist customers in this region - specifically with the Autojet and Spray Analysis range of products.

Autojet Technologies is the turnkey systems division of Spraying Systems Co. and supplies a range of patented spray controllers and spray products, high speed automatic spray guns, spray lances and manifolds engineered for precision spraying, saving chemicals and water, minimizing manual labour and improving product quality.

Monitoring Engineering, Grant Orsmond, Tel: (011) 618-3860, Email: [email protected], www.spray.co.za

Pumps as good as newHytec, the largest supplier of hydraulic components and systems in southern Africa and part of the Hytec Group, has introduced a service exchange programme to ensure much faster turnaround times on pump repairs, benefiting both production and the customer’s bottom line.

The Service Exchange programme is a component replace-ment system that supplies refurbished units with a one-year warranty. Returned equipment is refurbished to factory speci-fication, while repair and service costs are well-priced and easily predicted. With this programme, machine downtime is kept to the minimum with selected immediately-available and directly off the shelf pump units.

“Customers who use our Service Exchange Units are guar-anteed that no shortcuts are taken, that only genuine parts as specified by the manufacturer are used, and that the pumps are subjected to rigorous inspection and function testing – including leak and pressure tests – before they

leave our premises,” explains Hytec engineering manager, André Lindeque. “This ensures that all units are repaired to original factory standards.”

“We are flexible in our approach. Specific service exchange programmes have been implemented to satisfy the unique product requirements of certain customers.”

Hytec, André Lindeque, Tel: (011) 975-9700, Email: [email protected]

With the Service Exchange programme, Hytec makes used pumps good as new





New compressor rangeEqstra Industrial Equipment, a division of JSE listed Eqstra Holdings Limited, recently entered into an agreement with Atlas Copco South Africa’s Multibrand division to distribute the ABAC compressor range.

Eqstra Industrial Equipment has exclusive distribution rights in Southern Africa for, amongst others, Toyota Forklilft, BT Warehousing equipment, Konecranes heavy duty forklifts and container equipment, Hako industrial cleaning equipment. The ABAC range now further extends Eqstra’s comprehensive product and service offering.

FLTR Technical Sales Manager Paul Combe and Eqstra Industrial Power Director Mariana Pretorius with Atlas Copco SA regional manager Multibrand - Sub Saharan Africa Ian Wild

Market ForumSeparation circuit for BooysendalFLSmidth has been awarded three contracts by Northam Platinum to supply a full range of ore processing equipment to its greenfields Booysendal Platinum Mine on the Eastern Limb of the Bushveld Complex in Mpumalanga.

The mine plans to treat 150 000 tonnes per month of UG2 ore. Following a successful trial demonstration, the first contract — awarded to FLSmidth in October 2010 — saw the world’s first deployment of Pneumapress automatic pressure filter technology in a platinum con-centration application.

“Pneumapress technology had been predomi-nantly used in the geothermal energy and food sectors, but is proving ideal for the minerals industry, dramatically improving filtration rates, while reducing operating and capital costs,” says FLSmidth sales manager, separation technology, Howard Areington.

“A Pneumapress filter does not use membranes and has individual filtercloths. Its unique feature is its isolatable plates which allow the filters to run, even when problems are encountered on one of the plates or with the filter media. In many cases, this technology also delivers a lower filtration area than has been previously possible, for a given feed rate.”

Northam has also ordered all the thickeners required for the concentrator, including installation, from FLSmidth, in diameters ranging from 27 to 35 m. The Eimco patented E-Duc dilution system was chosen for this application.

The mine has ordered FLSmidth’s Dorr-Oliver forced air flotation cells for the concentrator, ranging in size from 70 m3 to 5 m3.

Equipment supplied on all three contracts will be commis-sioned by mid-2012.

Flsmidth, Marinda Kerr, Tel: (010) 210-4820, Email: [email protected], www.flsmidth.com

New hydraulic brake for dry cooling tower fans Hansen Industrial Transmissions’s (HIT’s) hydraulic brake system (patent pending) for its M4 ACC (Air Cooled Con-denser) industrial gearboxes, allows the user to safely slow down the gear unit and condenser fan and keep them at standstill during maintenance activities in dry cooling towers.

Eqstra Industrial Power director, Mariana Pretorius explains that selective acquisitions within the industrial equipment and materials handling sector, combined with diversification of products and services enable the division to provide com-plete solutions to a wide spectrum of industry in Southern African and other countries on the continent.

The Atlas Copco Multibrand portfolio presents an extensive product range including professional and industrial recipro-cating piston compressors, oil lubricated screw compressors (either fixed or variable speed technology), oil-free units, compressor management systems, quality air products (including dryers and air receivers), spares, etc, to satisfy air demands as well as many and varied applications. The products feature industry-leading low noise levels, reliable, cost effective, energy efficient, easy to install compressed air solutions.

Eqstra reports they have everything in place for distribution of the ABAC compressor range, including parts, services and maintenance.

Atlas Copco Compressor Technique - Multibrand, Ian Wild, Email: [email protected] www.atlascopco.comEqstra Industrial Power, Mariana Pretorius, Email: [email protected]





Market Forum

With this hydraulic brake system, Hansen Industrial Gearboxes can now be equipped with a tool that avoids the risk of maintenance personnel being injured due to ‘windmilling’ (an idle fan which starts rotating due to airflow and thus driving the gear unit).

The system is unique in that the braking force not only holds the fan and gear unit when at standstill, but is capable of decelerating it to a safe stop within a limited braking time (maximum motor speed to be confirmed by HIT per project).

It consists of two hydraulic brake cylinders with brake shoes and a hand pump with hose. The brake cylinders are built onto the motor lantern and brake on the coupling between the motor and the gear unit. Due to the fact that it is a mobile solution, the investment is kept limited, since a single brake kit can serve a whole batch of fan drives.

Hansen Transmissions South Africa, Fritz Fourie, Tel: (011) 397-2495, Email: [email protected], www.hansenindus-trialgearboxes.co.za

The contract, valued at R15 million, comprises two Technogrid applications, one configured as a shaft conveyance over-wind impact arrestor, the other modified for Technopost duty as a station stopper for underground track-bound equipment.

Technogrid is a strain energy absorption system that stops moving objects through the stroke deformation of a metal grid of known design and characteristics. The grid itself comprises a series of multi-bar units connected in a stag-gered pattern. On impact, the grid bars yield and deform under double curvature bending, undergoing strain hardening that absorbs impact energies from 24kJ to 50MJ and more.

The unit, which allows the safe deceleration of large masses from high impact speeds, can be combined in series or parallel

Strain energy absorption systems for platinum mineEngineering group Horne has secured the contract for strain energy absorption systems at a platinum mine under development in Northwest Province.

www.mecad.co.za



Market Forum

Index to Advertisers

Atlas Copco 30AST Pyroshield Inside Front CoverAxiom Hydraulics Outside Back CoverBMG Outside Front CoverBearings International 19Bonfiglioli 4Chem Systems 12David Brown 14Engineer Placements 16, 26Engen 13Esteq 32Festo 40Hansen Industrial Gearboxes 31Ingersoll Rand 12Mecad 45KSB Pumps and Valves 10Pylon Gears 26SEW Inside Back CoverSKF 22

Please fax us if you wish to subscribe to “SA Mechanical En-gineer” at R400,00 (incl postage and VAT) per year; R945,00 per year for Africa/Overseas. We will post you an invoice on receipt of your fax.

PROMECH PUBLISHING Fax No: (011) 781-1403

From:......................................................................................

(insert your name)

Title: ......................................................................................

Company: ..............................................................................

Address: ...............................................................................

...............................................................................................

...................................................................Code: ..................

Telephone: ( ) ....................................................................

Fax: ( ) ................................................................................

Email:.....................................................................................

Subscription

On the Move

Chris CorreiaMalose Chaba

Francois van Tonder

Andy Brookstein

Les Lothian

Andy Brookstein has been appointed an executive director of the Esorfranki Limited Board.

Malose Chaba has been appointed as AfriSam Aggregate and Readymix chief operating officer. He replaces Grant Neser, who was appointed commercial executive of AfriSam.

Bell Equipment Sales South Africa has appointed Francois van Tonder as the general manager of the Coastal Region while Les Lothian, who previously held that position, has been appointed as general manager of the Central Region.

Chris Correia has been appointed Reef Fuel Injection Services sales representative.

configurations to suit the application. When configured as a Technopost station stopper, the Technogrid is mounted flush between the rails, with one end anchored to the footwall and the other attached to a vertically configured impact post. This post is always in the raised position, but may be lowered by activating a solenoid valve to allow traffic to pass over the device.

Horne Group, Andre du Preez, Tel: (011) 974-1004, Email: [email protected]

Technopost station stopper for underground

track-bound equipment



www.sew.co.za

SA Mechanical Engineer Oct11

Documents

Transcript of SA Mechanical Engineer Oct11