KLZ 2-92 Mechanical Seal Tech Manlo

HEATRIC - HEAT EXCHANGER USERS MANUAL Rev3 May 2011

Page 1 of 26

HEAT EXCHANGER USERS MANUAL

INSTALLATION, OPERATION & MAINTENANCE

INSTRUCTIONS FOR HEATRIC:

PRINTED CIRCUIT HEAT EXCHANGERS (PCHEs),

FORMED PLATE HEAT EXCHANGERS (FPHEs)

AND HYBRID HEAT EXCHANGERS (H2X)


Page 2 of 26

CONTENTS

FOREWORD.............................................................................................................................. 3

DEFINITIONS............................................................................................................................. 4

APPLICATIONS ......................................................................................................................... 7

DELIVERY INSPECTION........................................................................................................... 8

INSTALLATION.......................................................................................................................... 9

TESTING.................................................................................................................................. 11

STRAINERS & STRAINING..................................................................................................... 12

ASSOCIATED SYSTEMS........................................................................................................ 15

COMMISSIONING ................................................................................................................... 17

OPERATION ............................................................................................................................ 18

MAINTENANCE & INSPECTION............................................................................................. 19

CLEANING METHODS............................................................................................................ 21

HEATRIC AFTERSALES SERVICES ...................................................................................... 22

HEATRIC RECOMMENDED PRACTICES .............................................................................. 23

CHARACTERISTICS OF HEATRIC EXCHANGERS .............................................................. 24

CONTACTS.............................................................................................................................. 26


Page 3 of 26

FOREWORD The following guidance relates to the installation, operation and maintenance of Heatric manufactured heat exchangers. The guidance provided reflects the best practices developed from serving the hydrocarbon processing industry since 1985, as well as state of the art technology developed specifically for Heatrics products. Heatrics products have been used extensively throughout the upstream hydrocarbon processing sector as well as being adopted by the LNG production, LNG transportation and power generation sectors. It is fully expected that following these guidelines will result in extended & reliable service from the exchangers. Heatrics products are all of a bespoke nature and this document cannot cover all possible permutations of design and operation. Where equipment is not covered by this document then additional guidance will be provided as part of the final documentation package supplied with the exchangers. Sections of this document which Heatric consider to be critical to the safety of the equipment and personnel are highlighted. Extra care should be taken to fully understand these sections prior to any work being carried out in relation to the Heatric supplied equipment.

Heatric Exchangers for Advanced Applications The high integrity and high performance of Heatrics exchangers make them attractive for use in applications operating at extremes of temperature, pressure and process medium. Examples of these being heat recovery applications related to high efficiency power cycles, waste heat recovery systems and chemical reactions. Due to the bespoke nature of these applications they are not covered in this document. If you have an exchanger for use in an application outside of the main stream hydrocarbon processing applications then a technical appendix addressing application specific points will be issued By Heatric. If you have an interest in using a Heatric exchanger in conjunction with such an application please contact Heatric to discuss in further detail. This document is tailored towards Heatrics main market of hydrocarbon processing.


Page 4 of 26

DEFINITIONS

Printed Circuit Heat Exchangers (PCHEs) Printed Circuit Heat Exchangers are characterised as high integrity plate type heat exchangers. They are fabricated from flat metal plates that have fluid flow channels chemically etched into them. The etched plates are diffusion-bonded and headers and nozzles attached to form complete exchangers. No gaskets or braze metals are employed in the construction of the heat exchange core. They are particularly well suited to high pressure services.

Figure1: cross section of PCHE core construction. Formed Plate Heat Exchangers (FPHEs) Formed Plate Heat Exchangers are constructed by sandwiching corrugated fin pads between parting sheets, a method comparable to that used by the various fin plate heat exchangers but adds the advantage of replacing the brazing process with the diffusion-bonding process. This enables Heatric to manufacture the FPHE in various alloys previously considered both challenging and expensive. This type of exchanger is considered to be best suited to applications which require low pressure drops, due to the larger flow channels that can be offered.

Figure 2: Cross section of an FPHE core construction Hybrid Heat Exchangers (H2X) Hybrid heat exchangers combine the high performance and pressure capabilities of the PCHE construction with the lower pressure drop offering of the FPHE.

Figure3: Cross section of Hybrid Core construction Operating pressure ranges of each construction can be found in figure 16 on page 22 of this document. Diffusion Bonding Diffusion-bonding is a "solid-state joining" process entailing pressing metal surfaces together at temperatures below the melting point, thereby promoting grain growth between the surfaces. Under carefully controlled conditions, diffusion-bonded joints reach parent metal strength and stacks of plates are converted into solid blocks containing the fluid flow passages. No gaskets or braze metals are employed in the construction of the heat exchange core.


Page 5 of 26

Nozzles These are piping sections used to connect the exchanger to the customers process piping. These can be finished in a variety of ways to suit customer requirements, most commonly flanges, mating hubs or weld preparations. Headers Headers are half cylinders which allow fluid distribution between the nozzles and the channels in the exchanger core. Ports Ports are effectively integral headers which allow fluid distribution areas to be formed inside the exchanger core. These are similar to the distribution areas seen with plate and frame exchangers, but designed for much higher pressures thanks to the diffusion bonded construction. Supports There are a variety of methods of supporting Heatric exchangers. The most common method is by the end type supports which are welded to the exchanger core.

Figure 4: Typical end mounted supports Alternative methods such as saddle supports, which are fitted to the lower header in the vertical plane can be offered.

Figure 5: saddle type supports

Lifting Lugs These are typically located on the ends of the exchanger, as seen in figure 5, and are suitable for fitting with Dee shackles in accordance with BS 3032 and DNV 271 to attach lifting strops. Where typical end supports are used the lifting points will be incorporated into the support, as seen in figure 4. Alternative lifting points can be provided, please discuss your requirements with us. Plates These are the sheets of stainless steel or higher alloy which are used to form the heat exchanger core for PCHEs or H2X constructions. These have the fluid flow channels chemically etched into them.

Figure 6: PCHE core plates Fins These corrugated panels mechanically formed from stainless steel foils or higher alloys. The corrugations form the fluid flow passages when sandwiched between parting sheets. Fin pads are available in many geometries such as straight, wavy and herring bone.

Figure 7: fin pads


Page 6 of 26

Parting Sheets Sheets of stainless steel or higher alloy which are used to sandwich the finpads to form fluid flow channels. Side Bars These are solid pieces of metal which frame the fin pads when they are sandwiched by parting sheets. They form the outside edges of the heat exchanger and provide areas for the headers to be welded on to the exchanger core. Block To Block Joints For large thermal duties more than one diffusion bonded block may be required. In such cases the blocks are butt welded together endplate-to-endplate to form an all-welded heat exchange core. Each gap between blocks is connected to an interblock vent to confirm the absence of pressure between the blocks. Similarly the void between the duplex sheathing and the core is connected to this vent.

Figure 8: block to block welding Sheathing Sheathing is the term used for the sheet metal cladding sometimes applied to the outside surfaces of stainless steel cores for enhanced environmental protection in marine environments.

Design Codes Heatrics exchangers are designed to meet international standards. Primarily we work to the ASME VIII Boiler & pressure vessel code, however other codes can be accommodated at client request. In addition Heatric hold both an ASME U Stamp and ASME R Stamp. Heatric operates an Integrated Management System which encompasses: ISO 9001, ISO14002 and OHSAS 18001 which is certified by Lloyds Register.

Materials of Construction Heatric currently offer heat exchangers in the following materials:

Stainless Steel 304 Stainless Steel 316 22 Chrome Duplex (UNS S31803) Titanium (Grade 2) 6 Moly

We continue to develop alloys for new markets. Should you require materials not shown on the list then please discuss this with us. Clean Fluids Heatric exchangers are recommended only for use with clean fluids, due to the small passage sizes. Examples of clean fluids: Hydrocarbon gases and condensates, closed loop utilities, refrigerants, seawater. Fluids generally considered unsuitable for use: crude oil, open loop utility, fluids with high particulate loading.


Page 7 of 26

APPLICATIONS Heatrics exchangers are used in a wide variety of industries, serving in many different applications. However the nature of these applications generally fall into one of two categories: Primary Systems Where the process fluids passing through the exchanger are inter-dependant. An example of this type of service is the cold recovery gas-gas exchanger in a low temperature separator system. Secondary Systems Where the fluids are independent of each other. An example being a compressor after-cooler, where the gas and cooling utility can be controlled independently of each other. The control and inspection requirements of both these types of system will be discussed later in this document.


Page 8 of 26

DELIVERY INSPECTION Delivery Inspection Upon delivery the heat exchanger should be inspected to ensure it is free from shipping damage and contamination. Care should be taken when removing packaging to ensure that no damage is inflicted upon any protective coatings applied to the exchanger or to the exchanger itself. Packaging Typical packaging for shipment is for the nozzle openings to be covered with rubber gaskets and painted steel cover plates. The plates are held in place by 4 bolts. The generally the exchanger is mounted on a carbon steel transport frame and shrink wrapped in plastic. Lifting points are exposed for ease of moving during shipment. Small exchangers may be packaged in wooden crates for shipment where the carbon steel transport frames are not practical. Upon client request larger items can be provided with wooden boxes positioned over the carbon steel frames or packed in an ISO shipping container if practical. Internal Inspections For exchanger shipped using Heatrics normal packing methods visual inspection of the heat exchanger internals can be made by removing the flange covers on the main process nozzles. After inspection, replace all flange covers and re-seal. Providing the unit is stored under cover in a dry environment, it can then be stored without further preservation activity being required. For exchangers shipped with pressurised dry nitrogen atmospheres care should be taken when releasing the pressure. These units typically have pressures of about 1 bar(g) (15 psig). Once the pressure has been released the valves, gauges and blind flanges on the main process nozzles can be removed to allow visual inspection.

After inspection all flanges, valves, gauges and fittings should be reattached and the units purged and re-pressurised in accordance with the provided procedures. The exchangers can then be stored until required. Should either shipping damage or internal contamination be discovered, contact Heatric for guidance. Storage When packed as described above the exchangers are suitable for storage outside for short periods of time. Once the exchanger has been unpacked it is strongly recommended that the items be stored under cover in a dry environment. Long Term Storage If it is planned to store the Heatric exchanger for a period of 6 month or more prior to installation consideration of a preservation method should be considered. Generally an inert gas blanket is used, however options for liquid preservation can also be provided. After inspection all flanges, valves, gauges and fittings should be reattached and the units re-pressurised in accordance with the provided procedures. The exchangers can then be stored until required


Page 9 of 26

INSTALLATION Associated System Preparation Prior to installing the equipment or connecting the associated piping to the exchanger(s) we would recommend that the following steps be taken: Inspection of the lines for obvious physical

installation debris. Retro-jetting or pickling and passivating of

the piping systems to ensure removal of pipescale or similar corrosion products.

Flushing and draining of the system to ensure removal of any removal of pipescale, similar corrosion products or installation debris.

Special Tools No special tools are required for the installation or maintenance of the PCHE. Lifting Prior to lifting the exchanger reference should be made to the weight data sheet for the actual recorded weight and lifting information such as size and Centre of Gravity. Heatrics Recommended Lifting Points Heatric recommends that the exchanger should be lifted using the lifting lugs welded at each end of the exchanger, not with flanges or nozzles. The lugs can be either separate or incorporated into the support gussets, see Fig 1. The lifting lugs are designed to take D shackles in accordance with BS 3032 and DNV 271 and lift at least twice the weight of the exchanger. Load test certification is supplied as part of the documentation pack provided with purchased equipment. Note: Should an alternative lifting method be required for any reason, please contact Heatric for confirmation that this will not damage the exchanger.

Heatrics Recommended Lifting Method Shackles should be attached to the lugs such that the legs of the slings are evenly distributed and the lifting hook is positioned over the Centre of Gravity, to ensure optimum stability. Any loose objects on the exchanger should be removed and the strain taken until the weight of the exchanger is fully supported by the lifting lugs. The PCHE should then be unbolted and removed from its transport frame. The unit should then be lifted into place, taking care not to cause damage which could affect its operation and be secured by bolting through the supports on each end of the unit to the appropriate structural steelwork. Lifting equipment should only be removed when the unit is securely mounted to the steelwork.

Figure 9a Typical lifting illustration.


Page 10 of 26

Figure 9b Heat exchanger being lifted using recommended method. Connections Prior to connecting the heat exchanger to associated pipework reference should be made to nozzle loads and moments detailed on the manufacturing drawing. During the connection process steps should be taken to ensure that the piping forces and moments transferred to the exchanger nozzles do not exceed those listed on Manufacturing Drawing. No connection to the interblock vent is required. Venting & Draining The heat exchangers are largely self venting and draining through the process nozzles. Consequently provision for venting and draining should be made in the adjacent pipework. Supplementary vent and drain connections can be added where exchanger geometries may result in trapped pockets of fluids within the header spaces.

Earthing Heatric exchangers are provided with earthing bosses for connection to the main earthing loop of the facility. Alignment In general the thermal performance and operation of Heatric exchangers will not be adversely affected if the unit is installed slightly out of plane or by vessel motion. For exchangers that incorporate fluid distribution systems, for glycol or 2 phase mixing, additional guidance will be provided as part of the final documentation package supplied with the exchanger. Instrumentation No instruments are supplied as part of the PCHE package. In order to assess the performance of the exchanger and for troubleshooting of control problems, the following should be monitored and preferably recorded: Stream inlet and outlet temperatures Stream pressure drops - across exchanger

and across strainers Stream flow rates Control valve position Utility stream pressures Over-Pressure/Temperature Protection The design temperatures and pressures are shown on the Manufacturing Drawing and Nameplate Detail. Do not operate outside these limitations. Safety Note: Pressure relief equipment is not supplied with the PCHE. Precautions should be taken to ensure suitable pressure relief valves and other equipment is installed in the adjoining pipework to ensure temperatures and pressures are kept within the design limitations.


Page 11 of 26

Insulation & Guards The equipment can be expected to operate at temperatures that could be hazardous to personnel. Heatric exchangers can be fitted with tags to allow attachment of insulation or personnel guards as required to provide personnel protection. Cold Insulation or personnel guards are not supplied by Heatric. Fire protection systems No provision is made for fire proofing or fire protection systems as part of Heatrics scope of supply. Provision for this should be made within the overall facilities protection system.

TESTING Heatric exchangers are designed in such a way that either chamber can be fully pressurised independently of the other. Do not exceed the hydrostatic test pressures specified on Manufacturing Drawing and Nameplate Detail when carrying out hydrostatic testing of the pipework connected to the exchanger. Routine integrity testing of equipment and associated piping systems should be carried out at pressures not exceeding the design pressure stated on the exchanger name plates. Employ low-chloride water (preferably


Page 12 of 26

STRAINERS & STRAINING In common with all compact heat exchangers, strainer protection is generally required to protect PCHE passages from blocking by oversize particulates. Excessive build-up of particulates in strainers can lead to rupture of the strainer element, with the particulate load making its way downstream to the exchanger inlet. Strainer pressure drop should be monitored to ensure that it does not become excessive for the strainer element limit of typically 0.5 bar. Note: this guidance is targeted at the main upstream hydrocarbon processing market. For other market sectors please contact Heatric for guidance specific to your operations. In Line Conical Type As a minimum we recommend installing Heatrics proprietary high integrity in-line conical strainers on the gas side and online serviceable / cleanable wedge wire strainers for the cooling medium side. The conical strainers should be installed in a short pipe spool piece (for easy removal) upstream of the gas inlet as close to the exchanger as possible. After commissioning, the strainers should be cleaned, checked for integrity, and then replaced in line for normal operation.

Figure 10: Heatric in line conical type strainer

Figure 11: Schematic of Heatric in line conical type strainer installation


Page 13 of 26

Heatric Integral Tee Type As an option, we recommend a more manageable solution by offering a Tee-type strainer housing arrangement for gas inlets. The Tee-type strainer can be easily inspected, cleaned/replaced by removing the basket from the blinded end of the Tee without having to remove any spool pieces from the process piping.

Figure 12: Heatric Tee-type strainer housing for gas side

Figure 13: Schematic of Heatric Tee-type strainer housing for gas side

Figure 14: Heatric Tee-type strainer basket for gas side (housed in Tee in Figure 12)


Page 14 of 26

Mechanically Cleanable Type Mechanically cleanable type strainers employ rotating screens and rigid scraper bars to remove solids from the surface of the screen when the screens are rotated. A solids collecting sump is also provided. Cleaning of this type is accomplished by opening a valve on the sump flush connection and rotating the screens several times. The cleaning cycle must be performed when the strainer is under positive pressure.

Figure 15: Mechanically cleanable type strainer

Benefits of this type of strainer are:

Eliminate downtime for solids removal allows users to eliminate solids and debris from fluids without stopping the flow of the fluid.

Employees are not exposed to possible contaminants Debris that may include contaminants and hazardous materials is removed from the fluid flow without disassembly of the strainer.

Minimum labour requirements for solids removal

This type of strainer is recommended for fluids which may be prone to regular high levels of foulant build up, such as closed loop coolant systems.


Page 15 of 26

ASSOCIATED SYSTEMS Open Loop Coolant Systems It is strongly recommended that Heatric exchangers are not used in conjunction with open loop systems. As these systems are open to the general atmosphere they are prone to environmental contamination which cannot be controlled. This increases the risk of potential for fouling of the exchangers. Closed Loop Coolant Systems The application of good practice in the engineering of the closed-loop coolant system and sound maintenance of the coolant are crucial to the long-term performance and integrity of a cooler and its associated system. The following are minimum measures for the design and operation of the closed loop coolant system: a) Prior to installing the equipment or

connecting the associated piping to the exchanger(s) we would recommend that the following steps be taken: i) Inspection of the lines for obvious

physical installation debris. ii) Retro-jetting or pickling and passivating

of the piping systems to ensure removal of pipescale or similar corrosion products.

iii) Flushing and draining of the system to ensure removal of any removal of pipescale, similar corrosion products or installation debris.

b) Charge the cooling circuit with non-scaling,

low-chloride water. Demineralised water is ideal if available. Avoiding scale is important as scale interferes with heat transfer, and may also promote concentration of corrosive species beneath it.

c) Maintain a sufficiently high glycol

concentration in the coolant to avoid coolant freezing during protracted winter shutdowns.

d) Maintain the coolant operating pressure

higher than both:

i) the coolant vapour pressure at the maximum gas operating temperature, to ensure that the coolant does not boil during low flow or turndown conditions (that is, keep the coolant pressure high enough so that it would not boil even if stagnant)

ii) the pressure should be based on static system pressure and not rely on pump head to ensure that coolant cannot boil in the event of circulation pumps tripping, and

iii) the seawater pressure, to ensure that any leaks in the central seawater cooler do not enter the closed loop.

e) Blanket the header tank with inert (oxygen

free) gas to pressurise the system where necessary and to avoid chloride ingress and oxygen uptake.

f) Inhibit corrosion in carbon steel coolant

piping with suitable additives. Maintain the coolant pH neutral or alkaline.

g) Suppress biological growth. h) Avoid the use of coolant additives (including

glycol) which might break down at the gas inlet temperatures.

It is strongly preferable to commission the coolant system at full flow prior to commissioning the hydrocarbon system. This provides the opportunity for orderly servicing of coolant strainers when the particulate load is high. Consider the use of side-stream filtration to polish the coolant in carbon steel piping systems to avoid recirculating high levels of fine suspended solids. Note: side stream filtration is not an alternative to 100% straining of streams entering the exchanger. It is a possible additional measure to improve the general quality of the coolant. Losses of the closed loop coolant should be minimised, as this will simplify maintaining its composition within specification, and minimise make-up costs and inconvenience.


Page 16 of 26

Glycol Regeneration Systems Where lean glycol is being added for hydrate suppression it is important that the fluid is kept in good order. The regeneration system and the fluid itself should regularly be inspected to ensure the glycol is not degrading during the regeneration process. Degraded glycol will foul the exchanger resulting in the need to shut down production and clean the exchanger. Heating Utility Systems Where a heating medium is being used it is important that the fluid is kept in good order. The heating system and the fluid itself should regularly be inspected to ensure the fluid is not degrading during the reheating process. Degraded heating medium will foul the exchanger resulting in the need to shut down production and clean the exchanger. Refrigerant Systems Where a refrigerant system is used in association with Heatric exchangers there are 3 points that need consideration during commissioning and operation. 1) System cleanliness prior to initial refrigerant

charge. As with all other systems it is important that associated piping and vessels are clear of construction debris and scale.

2) Compressor seal degradation: Generally

these systems use reciprocating devices with seal rings which can degrade leading to foulant build up in the system.

3) Seal/Lubricant oil contamination: Where

such contamination of the refrigerant fluid occurs the resulting accumulation over time can lead to an oil film forming on heat exchange surfaces. This film will inhibit the heat transfer performance of the exchanger, leading to a need to clean the exchanger and probably the whole system.


Page 17 of 26

COMMISSIONING Heatric exchangers have no moving parts or integral parts needing set up during commissioning. However the straining, utility and control systems associated with the exchangers require set up and monitoring during commissioning. The following section is intended as an over view of steps required, further detailed recommendations are available from Heatric. Associated System Preparation

Recommended precautions for the associated systems are made in the Installation section of this document. Control Systems Set Up Control equipment Control equipment is not provided with the PCHE. In order to assess the performance of the exchanger and for troubleshooting of control problems, the following should be monitored and preferably recorded: Stream inlet and outlet temperatures Stream pressure drops - across exchanger

and across strainers Stream flow rates Control valve position Coolant pressure Controller settings Compact heat exchangers have a very small thermal mass so that the internal metal temperature responds very rapidly to changes in process conditions, particularly flows. In contrast, devices for measuring gas outlet temperature respond more slowly, thus the measured temperature will lag behind the actual temperature. A rapidly responding coolant control system can therefore introduce unwanted and damaging instability. Such instability can give severe cyclic thermal stress within the core, leading to fatigue cracking and inter-stream leakage, within months, or sometimes only weeks of start up. Whilst the fatigue cracking gives no immediate

danger of external hydrocarbon release, the PCHE will need to be taken out of service for rectification. Temporary repair is often possible, but this will have a limited life, so a new core is the only permanent option. These instabilities are generated entirely by the control systems, even when the process inputs - gas flows and inlet temperatures are not varying. PCHEs are fully suitable for all normal and expected operating conditions.


Page 18 of 26

OPERATION Pressurising Heatric exchangers are designed in such a way that either chamber can be fully pressurised independently of the other. Ensure all connections are checked for correct sealing before operation. Fluid Flow [Compression Coolers] Start up Establish coolant flow prior to gas flow in order to restrict the rise in core temperature. Prevent extreme throttling of the coolant flow by means of a stop on the coolant control valve, set to as high a value as possible. Note that during start-up temperature and flow changes transients in compressor aftercoolers are very rapid. To ensure there is adequate coolant flow throughout start-up, it might be necessary to either: Set the minimum stop on the coolant control

valve to position where the resultant coolant flow exceeds that required for the start-up gas flow and temperature, or

Override the control system during start-up to allow full coolant flow.

Shut down Discontinue the hot gas flow first, as this will avoid heating the metal core above the operating temperatures. Fluid Flow [Heaters] Start up Establish cold gas flow prior to heating utility flow in order to restrict the rise in core temperature. Shut down Discontinue the heating utility flow first, as this will avoid heating the metal core above the operating temperatures.

Fluid Flow [Gas Gas Exchangers] As this is a primary system, described in applications section, It is expected that both streams will start or stop flowing through the heat exchanger together. Blow-Down Gas Where possible, cold blow-down gas should be routed away from exchangers to avoid the potential of freezing liquids within the exchanger and imposing transient thermal stresses on the exchanger. During blow-down, ensure exchanger metal temperatures do not fall below the minimum design temperature stated on the exchanger name plate. Where the core material is 22 Cr duplex and the core has been cooled below -29C during blowdown, the core must be reheated slowly to above -29C before restarting. Emergency Shut Down Under emergency conditions Heatric exchangers can be rapidly shut down by operation of the isolation valves in the process pipework local to the exchanger. Heatric exchangers are designed in such a way that either chamber can be fully pressurised independently of the other. Either side of the unit can therefore be taken out of service as required, although preferably the shutdown sequences described for the application should be followed.


Page 19 of 26

MAINTENANCE & INSPECTION Design for Maintenance Heatrics exchangers are bespoke solutions tailored to meet the clients needs. Heatric offer a number of design configurations that allow improved access for some of the cleaning methods described in this document. Options available include: End Fed Headers This option positions the main process nozzle on the end of the exchanger, rather than the traditional central position. This then offers greater access to the heat exchanger cores face for UHP water jet cleaning. This option is particularly suited for compression after coolers, where poorly maintained closed loop coolant systems can result in foulant build up.

Figure 16 end fed header configuration. Additional Access Nozzles In cases where end fed headers cant be accommodated, then additional maintenance nozzles can often be fitted. When specifying these it is important to ensure that these are practical for use and do not impinge on supports structures or similar associated items.

Figure 17: Additional access nozzles

Maintenance Blinds In cases where additional maintenance nozzles cannot be fitted then maintenance blinds for chemical cleaning are an alternative option to be considered. Maintenance blinds are a cost effective way of simplifying the connection of chemical cleaning recirculation systems to the main exchanger process connections. The maintenance blinds are blind flanges of equivalent size and rating as the main process connections. These have been drilled and fitted with 50 NB (2 NB) flange connections for connecting up to the cleaning recirculation system. This removes the need for expensive piping reducers or similar couplings. Routine Maintenance Heatric exchangers have an all welded and diffusion bonded construction, meaning that there are no moving or serviceable parts. That is not to say that the exchangers should simply be installed and forgotten about. It is recommended that the exchangers be given external and internal visual inspections periodically. Internal inspections to check for signs of debris or fouling are recommended to be incorporated into the routine maintenance schedules for the compressor equipment. Items associated with the exchangers which may require inspection and intermittent replacement are the strainers and gaskets between the exchangers and mating process piping. Note: Guidance on strainer maintenance, monitoring and inspection are given under the strainer section of this document.


Page 20 of 26

External Inspection External inspections should in the first instance be visual inspections. Attention should be given to the following points:

Coating is it intact Signs of external corrosion Welded joints

Note: not all welded joints will be obvious to the eye, refer to weld maps provided in the manufacturing record book for details of your exchanger. The outcome of the visual inspection will determine what, if any, additional inspection may be required. If the visual inspection raises any concerns, contact Heatrics aftersales department. Internal Inspection Internal inspection should in the first instance be a visual inspection of the header space and core face, either by eye through the process nozzle or boroscope through any connection permitting access. Visual examination of the header space and core inlet and outlet faces is usually sufficient to identify when foulant accumulation has occurred. It is also the first stage in identifying the nature of the foulant. Unplanned Maintenance Should you face operational difficulties with your Heatric exchangers resulting in loss of performance, contact Heatrics aftersales department for advice. Depending upon the initial diagnosis it may be required that the exchangers be shutdown and internally inspected.


Page 21 of 26

CLEANING METHODS The following are some cleaning methods available. The list is not exhaustive and Heatric always welcomes information on new, or improved, cleaning methods

Back puffing

Back puffing uses a high-pressure gas to expel, or at least loosen, debris from within the exchanger core. This method has proved to be successful as a stand-alone cleaning method or as one treatment in a cleaning programme. For instructions, refer to Heatrics Recommended Practice RP 312 Back puffing.

Back flushing

Back flushing is a cleaning method using a large volume of water to flush through the exchanger core to expel debris. This treatment is useful when the foulant has not become too heavy or aged as the water will flow preferentially through unblocked channels. Flush in the opposite direction to normal flow and always use demineralised, or at least clean, non-scaling water which is low in chlorides (


Page 22 of 26

HEATRIC AFTERSALES SERVICES We have an Aftersales Department dedicated to provide support to your project. The overriding aim of the Aftersales Department is to maximise your production by optimising exchanger up-time (availability). Our range of service offerings are listed below: Operator training & sharing of best practices Strainers supply, servicing & replacement Site service support Performance review Onshore & offshore cleaning Onshore weld repair Spares Training Due to the unique features of our equipment Heatric offers one day training sessions about our heat exchangers at your on-shore location. These primarily target commissioning and operating personnel. The training package provides sufficient information to enter the exchangers into service. The training courses will cover:- Product description, manufacturing steps &

comparisons with other conventional heat exchangers

Project specific details: Commissioning, Operating and Maintenance activities i.e. start up, shut down considerations

Troubleshooting: What can go wrong, how to avoid problems, what to do if problems arise, performance monitoring

Case studies Q&A Pricing for the onshore training courses is available from our aftersales team.

Site Attendance We have a commitment to lifecycle support from the design stage through to operation. Our design engineers are available for consultation at client's base during the design stage. We have dedicated team of Customer Services Technicians able to provide onsite technical and labour support covering installation, commissioning and maintenance support as required. Should you require assistance, our current rates are available from our aftersales team.


Page 23 of 26

HEATRIC RECOMMENDED PRACTICES The following recommended practice documents are available from Heatric upon request:

RP 301a - Performance monitoring for Heatric coolers

RP301b - Performance monitoring for Heatric gas/gas exchangers

RP302 - Straining for Heatric compact diffusion bonded heat exchangers

RP303 - Closed loop coolant

RP305 - Monitoring of Heatric compact diffusion bonded heat exchangers

RP310 - Cleaning of Heatric compact diffusion bonded heat exchangers

RP312 - Back puffing for Heatric compact diffusion bonded heat exchangers

RP314 - Deriming for Heatric compact diffusion bonded heat exchangers

RP320 - Nitrogen preservation of Heatric compact diffusion bonded heat exchangers

RP321 - Liquid preservation of Heatric compact diffusion bonded heat exchangers

RP323 - Simple leak test for Heatric compact diffusion bonded heat exchangers

RP324 - Helium leak testing of Heatric compact diffusion bonded heat exchangers


Page 24 of 26

CHARACTERISTICS OF HEATRIC EXCHANGERS

Heatric heat exchangers are high integrity plate type exchangers. Heatric exchangers can be designed for pressures in excess of 600 bar and temperatures from deep cryogenic to in excess of 800C.

Figure 18: Heatric exchanger design envelope This capability envelope, far beyond that of all other compact heat exchangers, means that Heatrics exchangers are considered to be a compact alternative to shell & tube exchangers. When compared to the equivalent shell & tube exchanger a Heatric exchanger is typically 20-25% of the size and weight. This translates into greatly reduced costs associated with foundations, support structure, pipe work and installation.

Figure 19: Heatric exchanger compared to equivalent S&T exchanger. Same mass flows, thermal duty and pressure drops. S&T 108 tonne, Heatric exchanger 15 tonne.

This is achieved without compromising on thermal or hydraulic constraints; in fact using a Heatric exchanger could allow further process optimisation: Close Temperature Approaches

The compact nature of Heatrics exchangers means that very close approach temperatures can be achieved in a single exchanger, compared with multiple shell & tube exchangers that would be required as the alternative.

Figure 20: Close approach temperatures achievable in Heatric exchangers Fluid Injection Where glycol addition for hydrate suppression is required or liquid redistribution is necessary for a 2 phase fluid Heatric offers passage by passage distribution. Using an integral distribution matrix gives superior distribution compared with other methods of distribution available.

Figure 21: exchanger plates with fluid distribution passages.


Page 25 of 26

Multi Stream Capability Heatric exchangers can also combine multiple process streams into a single exchanger.

Figure 22: 3 stream exchanger with glycol injection. Safety

Heatric exchangers are immune from vibration and have no failure mode analogous to tube failure in shell and tube exchangers.

Heatric exchangers have no removable or serviceable parts, other than the gaskets between the process pipe work and the exchanger nozzles.

Pressure relief systems associated with Heatric exchangers are much smaller than those required for the equivalent shell & tube exchanger

Our materials of construction are immune to attack by mercury.

Welded and diffusion bonded Heatric exchangers employ no gaskets or braze material. As a consequence Heatric exchangers are immune to the thermal stresses described in ISO 15547-2, A 4.1 and are not restricted by the temperature differentials between fluid streams that the standard suggests appropriate for brazed aluminium equipment in section 6.4

Heatric exchangers also offer the benefit of not needing strict control of temperatures, associated with cold boxes, during start up, shut down or change of operating mode.

ISO15547-2 recommends that a rate of temperature change of not more than 2C per minute should be used for a brazed construction compact exchanger. There is no such limitation for a diffusion bonded exchanger.


Page 26 of 26

CONTACTS General Contacts Heatric UK (Main Office) 46 Holton Road Holton Heath Poole Dorset BH16 6LT United Kingdom Tel: +44 1202 627000 Fax: +44 1202 632299 Email: [email protected]

Heatric USA 11490 Westheimer Suite 850 Houston Texas 77077 United States of America Tel: +1 713 978 7236

Aftersales Service Enquiries Aftersales activities are run from the main office in the UK. Please direct any enquiries relating to aftersales activity to [email protected] or contact us at the main office detailed above.

Local Representatives A list of Heatrics local representatives can be found on our website. www.heatric.com

KLZ 2-92 Mechanical Seal Tech Manlo

Documents

Transcript of KLZ 2-92 Mechanical Seal Tech Manlo