Manajemen Perawatan

EDUCATE – ENHANCE – EMPOWER http://www.its.ac.id/personal/dataPersonal.php?userid=priyanta Rev. October 2013

Marine Engineering

4 Work Book 4: Major Maintenance Business Process

ME091325 Maintenance Management

Course Instructor: Dwi Priyanta

Department of Marine Engineering – ITS


Work Book :4 Major Maintenance Business Process

© Dwi Priyanta of 11 EDUCATE – ENHANCE – EMPOWER Rev. Sept. 2013

CONTENTS

1. Business Process : An Overview ................................................................... 3 1.1. Major Process .............................................................................................. 4 1.2. Sub-Process ................................................................................................. 4 1.3. Activities ...................................................................................................... 4 1.4. Task .............................................................................................................. 4

2. Major Maintenance Business Process : An Overview .................................. 5 3. The game of Maintenance Business Process Development ........................ 6

3.1. Game 1 : The Euphoria! ............................................................................... 7 3.2. Game 2 : Expect the Unexpected! ............................................................... 8 3.3. Game 3 : The Downtime! ............................................................................ 9 3.4. Game 4 : The Improvement! ..................................................................... 10 3.5. Game 5 : The Documentation ................................................................... 11

The Icon

Information icon; instruction icon

Text Book Icon – You are required to read your text book or hand out materials before you fill out the blank text, to complete the graph or others depend on the given instruction.

Pencil Icon – You are required to write down or to draw on your workbook.

Discussion Icon – You and your group members are required to discuss the given problems and find the solutions.




1. Business Process : An Overview In many organizations, they have more than one business process, each consists of more than one major process.

Examples of business processes exist in an organization are:

Managing information resources Managing financial and physical resources Managing improvement and change Managing maintenance management

A process is a logical, related, sequential (connected) set of activities that takes an input and produce an output. Business process is process that established in an organization. As it can be seen in Figure 1, the hierarchy of processes starting from top level to lower level are:

major process subprocess activities tasks

Figure 1 Business Process Hierarchy




1.1. Major Process

A major process is process that usually involves more than one function within the organization structure, and its operation has a significant impact on the way the organization functions.

When a major process is too complex to be flowcharted at the activity level, it is often divided into subprocess.

1.2. Sub-Process

A subprocess is a portion of a major process that accomplishes a specific objective in support of major process

1.3. Activities

Activities are things that go on within a process or sub-process. They are usually performed by units of one (one

person or one department). An activity is usually documented in an instruction. The instruction will document the tasks that make up

activity. 1.4. Task

Tasks are individual elements and/or subsets of an activity. Normally, tasks relate to how an item performs a

specific assignment.




2. Major Maintenance Business Process : An Overview Maintenance management can be considered as a process management which manage input process to output process. One of the key successful of process management is to design business process which manage those processes effectively and efficiently. In term of maintenance management, the design of maintenance management process can be initiated by designing or adopting the available maintenance best practice models. The next step will be to translate the adopted model into maintenance business process. The roadmap is illustrated in Figure 2. The models have been discussed in workbook 2.

Figure 2 Roadmap to Develop Maintenance Business Process




Followings are the step to design maintenance business process. 1. Identify major maintenance business processes and link them

together in a logical way. 2. Generally, a major maintenance process is still to general and it

needs to be divided into some maintenance sub-processes. 3. Usually each maintenance sub-process is expanded into

detailed activities. 4. If the activity is still too complex, we may further expand it into

several tasks. TIPS: In practice, Major maintenance business process SHALL be

developed first. If this major maintenance business processes are drawn in a business process diagram, this diagram is also known as a Level 0 diagram. IDEF 0 provide the standard to draw the business process.

Next level of maintenance business process is Level 1 diagram. This diagram usually consists of some maintenance sub-processes which are related to certain major maintenance business processes. Sometimes, if the major business process is not so complex, this Level 1 diagram also consists of some activities.

If the maintenance sub-process is still complex, it is better to draw Level 3 diagram which consists of activities and tasks.

3. The game of Maintenance Business Process Development

There is an equipment catalogue along with this workbook. You and your group are required to read the manual first carefully. In this game, each group plays as a maintenance department of an imagine shipping company which operates commercial ships.




3.1. Game 1 : The Euphoria! Recall the functionability profile of restorable system / equipment. At the beginning of the profile, there is a point where the equipment is purchased by the company. As a group of maintenance department, discuss with your group what should your department do regarding the acquisition of this asset. Identify also the person(s) in the organization who will involve in this problem solving. TIPS Do the group brainstorming to identify what should the maintenance department do. Effective brainstorming should be led by a facilitator. Appoint one of your group member to be a facilitator. In this game you need to prepare the following properties. An A0 paper (You may use A0 cartoon paper). Tape 5 x 3 inch (127 x 77 mm) Sticky Notes Various Color Marker with thick tip

Tips to be a good facilitator: Make every team member speak up. Value every opinion of the member and record / write it down. I

usually write it down the keyword of the opinion with thick and bright color marker on a post it / sticky note. One post it for one keyword.

After all ideas, opinions and keywords are written, cluster them which have the same issue.

Discuss and select which idea(s) which seems to be the best solution or make sense.

Write down the consensus in the minutes of meeting (MOM).




3.2. Game 2 : Expect the Unexpected! Game 2 is the continuation of Game 1. After your group did some discussion regarding what should be done when the company acquire new equipment, the next thing your group should do is to think what the maintenance department and other department shall do when the equipment is in operation state or uptime state. As it has been discussed in workbook 1, the objective is to have high reliability or to have longer time to failure (TTF). As a group of maintenance department, discuss with your group what should your department do while the equipment at the operation state or uptime state. Hint: The best way to do this job is by identifying major maintenance

business processes when equipment (in this case, or the whole assets when you were already in the real world) is in functioning state (uptime) and then connect them in a logical way. If necessary, you may draw a flow chart.

You may break the major maintenance business process down into sub processes, tasks and activities.

Identify the person(s) in the organization who will involve in each business process you and your group have identified.

Identify also how they communicate each other. TIPS Do the group brainstorming to identify what should the maintenance department do. Effective brainstorming should be led by a facilitator. Appoint one of your group member to be a facilitator. In this game you need to prepare the following properties. An A0 paper (Use the same paper as in Game 1). Tape 5 x 3 inch (127 x 77 mm) Sticky Notes Various Color Marker with thick tip




3.3. Game 3 : The Downtime! Game 3 is the continuation of Game 2. This is the hardest part. In this game your maintenance department is challenged to develop major maintenance business process so that when the equipment down it is recovered quickly. Hint: Again, the best way to do this job is by identifying major

maintenance business processes when equipment prior to fail, during in a failed state (downtime) and after the equipment is put back in operation state. Connect all major maintenance business processes you have identified in a logical way. If necessary, you may draw a flow chart.


Identify also the person(s) in the organization who will involve in each business process you and your group have identified.

Identify also how they communicate each other. TIPS Do the group brainstorming to identify what should the maintenance department do. Effective brainstorming should be led by a facilitator. Appoint one of your group member to be a facilitator. In this game you need to prepare the following properties. An A0 paper (Use the same paper as in Game 1). Tape 5 x 3 inch (127 x 77 mm) Sticky Notes Various Color Marker with thick tip




3.4. Game 4 : The Improvement! Game 4 is the continuation of Game 3. So far, your group has identified major maintenance business process, sub process, tasks and activities when the equipment is just acquired, in operation state, as well as in failed state. The next step is, how to evaluate and to improve these business processes. Take a moment to look back the maintenance best practice models discussed in workbook 2. Continuous improvement is located at the upper part of the pyramid model. It is like Esteem needs or Self Actualization needs in Maslow’s hierarchy of needs. Discuss with your group how to develop maintenance management improvement business process. Hint: Again, the best way to do this job is by identifying major

maintenance business processes regarding to the improvement maintenance management process. Connect all major maintenance business processes you have identified in a logical way. If necessary, you may draw a flow chart.


Identify also the person(s) in the organization who will involve in each business process you and your group have identified.

Identify also how they communicate each other.




3.5. Game 5 : The Documentation You and your group have develop major maintenance business process through game simulation. Document all the business processes you have identified during the game simulation. Please double check whether there is a major business process(es) unrecorded. The documentation shall be formal and follow engineering best practice documentation. Success criteria Reporting Auditing Cost

Plate Heat Exchanger

Operational and Maintenance Manual

daniele

CORRECT OMD LOGO

TO AVOID HAND INJURIES, PROTECTIVE GLOVESSHOULD ALWAYS BE WORNWHEN HANDLING PLATES.

NOTICE

PROTECTIVE SHROUDS

IT IS THE RESPONSIBILITY OF EACH PERSON OPERATING ORREPAIRING EQUIPMENT TO TAKE THE NECESSARY PRECAUTIONSTO COMPLY WITH ALL APPLICABLE SAFETY REGULATIONS.

ALFA LAVAL PROVIDES PROTECTIVE SHROUDS FOR ALL OURPLATE HEAT EXCHANGERS. THESE SHROUDS WILL PREVENTPOSSIBLE INJURIES AND/OR DAMAGE AS A RESULT OF SUDDENLEAKAGE FROM THE PLATE PACKAGE.

List of contents

TO OUR VALUED CUSTOMER 1

• Alfa Laval Locations 1.1

THE NAME PLATE - AND THE 2

IDENTIFICATION OF THE EQUIPMENT

• Code Plate & Identification Number Locations 2.1, 2.2

GENERAL 3

• Storage 3.1, 3.2

• Lifting 3.3

• Foundation 3.4

• Installation 3.5

• Special Loose Flange Connections 3.6

THE MAIN COMPONENTS AND THEIR FUNCTIONS 4A

FOR PARALLEL FLOW UNITS

• List of Parallel Flow Units 4A.1

• Function 4A.2

• How It Works 4A.3

• Heat Transfer 4A.4

• Pressure Drop 4A.4

• Plates 4A.5

• Gaskets 4A.6, 4A.7, 4A.8

THE MAIN COMPONENTS AND THEIR FUNCTIONS 4B

FOR DIAGONAL FLOW UNITS

• List of Diagonal Flow Units 4B.1

• Function 4B.2

• How It Works 4B.3

• Heat Transfer 4B.4

• Pressure Drop 4B.4

• Plates 4B.5, 4B.6

• Gaskets 4B7, 4B.8, 4B.9, 4B.10

CHAPTER

List of contents

OPERATION 5

• Starting Up 5.1, 5.2

• Unit in Operation 5.3

• Shut Down 5.3

• The Risks of Not Complying With 5.4

The Start-Up and Shut-Down Procedures

OPENING AND CLOSING OF THE PLATE PACKAGE 6

• Opening 6.1, 6.2, 6.3, 6.4, 6.5

• Removal and Insertion of plates 6.6

• Closing 6.7, 6.8, 6.9, 6.10, 6.11

MAINTENANCE 7

• Cleaning 7.1, 7.2, 7.3, 7.4, 7.5

• Regasketing 7.6, 7.7, 7.8, 7.9

• End Plate II Gaskets For Parallel Flow Units 7.10

• End Plate II Gaskets For Diagonal Flow Units 7.11

FAULT DETECTION 8

• Leakage at Connections or Plates 8.1, 8.2

• Internal Mixing of Media 8.3

• Pressure Drop Problems 8.4

• Heat Transfer Problems 8.5

SUPPLEMENTARY PARTS 9

• Partition Plate 9.1

• Instrument Ring 9.2

CHAPTER

To our valued customer:

Thank you for purchasing an Alfa Laval Plate Heat Exchanger. As the world's largestmanufacturer of Heat Exchangers, we are very proud of our products and services. We value youas our customer and wish to assure your satisfaction. We have prepared this Instruction Manualto assist you with your Alfa Laval Plate Heat Exchanger in various situations. We suggest thatyou look through it carefully, and, above all, make it readily available to any personnel who mayneed it for reference.

1.1

1

2 The name plate - and the identification of the equipment

Model type and manufacturing numbers(s)

A name plate like the one shown below is fixed to the apparatus as shown above andit gives the following information

2.1

2The name plate - and the identification of the equipment

WHENEVER USING THE MANUAL, CHECK FIRST THAT THESERIAL NUMBER ON THE FRONT COVER IS IDENTICAL TOTHAT ON THE NAME PLATE OF THE EQUIPMENT.

IN ALL CORRESPONDENCE WITH ALFA LAVAL, PLEASE REFER TO THE MANUFACTURING SERIAL NUMBER, FORTRUE IDENTIFICATION OF THE EQUIPMENT.

WHENEVER CONTACTING ALFA LAVAL ABOUT A PART FORYOUR PLATE HEAT EXCHANGER, BE SURE TO STATE THEMANUFACTURING SERIAL NO.(S), AND MODEL TYPE.

This instruction manual has been issued for many differentmodels of Alfa Laval industrial PHEs. There are separatemanuals for industrial, sanitary, spiral, alfa rex, brazed & evaporator/condensor heat exchangers.

•

•

•

2.2

General3

3.1

STORAGE

In this section, names of heat exchanger parts are mentioned forthe first time. For your information, see Chapters 4A or 4BFUNCTION.

1. Unless otherwise agreed, ALFA LAVAL delivers the plate heat exchanger ready to be put inservice upon arrival. This means that theplate package is tightened to its correct measurement A.

Should it be necessary, however, to store the equipment for alonger period (1 month or more) before, certain precautions shouldbe made in order to prevent unnecessary wear of the equipment:

Preferably, the heat exchanger should bestored inside, in a room with a temperaturearound 15 to 20 degrees Celsius (60 to 70degrees Fahrenheit) and humidity around 70%

2.

There should ABSOLUTELY NOT be anyOZONE-PRODUCING equipment in the room,like electric motors or arc-welding equipment,since ozone destroys many rubber materials(cracking).

Do not store organic solvents or acids in theroom.

Avoid heat or ultraviolet radiation.

Wrapping the PHE with a non-transparentplastic film is a good precaution. Use oftransparent film can alter paint color if unit isstored in direct sunlight.

3.

A

3

STORAGE

General

The tightening bolts should be well coveredwith good rust preventing coating, suitabletypes (LUBRIPLATE FGL-2 or Equivalent) andif not connected to the pipe system, the con-nections should be covered.

If the heat exchanger must be stored outdoors,the precautions mentioned above should betaken as far as practical. The need for protec-tion against the climate etc. is of course evenmore important in this case.

If for any reason the heat exchanger isremoved from service for a long period, it isadvantageous to follow the advice above, evenif the equipment is not moved from the location.

The heat exchanger should be VENTED ANDDRAINED, and depending on the media processed, it is recommended to RINSE ANDDRY it, before it is stored.

Whenever the heat exchanger is lifted, strapsshould be placed around tightening bolts on both sides of the unit, as shown in picture. Iflifting lugs or lifting eyes are provided, alwaysuse chains or lifting cables rated above thepublished weight of the heat exchanger.

4.

5.

1.

LIFTING

NEVER LIFT BY THE CONNECTIONS OR THE STUDS AROUND THEM!

3.2

General

3.3

LIFTING CONTINUED

If Lifting Lugs are provided

If you are to lift the heat exchanger itself, strapsshould be used. They should be placed asshown on the picture.

On smaller units (4” connected size smaller)typically two lifting lugs are required instead of four.

WARNING!Never lift by the connections or the studsaround them.

3

3GeneralFOUNDATIONS.

All information necessary for the preparation of the foundationappears on the data sheet provided by ALFA LAVAL.

In some cases (installation on board a ship,when processing corrosive liquids, etc.) it maybe practical to place the heat exchanger in aDRAINAGE BOX (with capacity for the totalvolume of the heat exchanger). The outlet ofthe drainage box should be generouslydimensioned, not less than (2”) 50 mmdiameter.

INSTALLATION.

BEFORE connecting any piping to the heat exchanger, MAKE SURE THAT ALLFOREIGN OBJECTS HAVE BEEN FLUSHED OUT OF THE SYSTEM!

PLEASE OBSERVE THATThe measurements given in the picture aboveare recommended by ALFA LAVAL, it isnecessary to leave free space around theequipment, to provide access and make futureservice possible. Except for a place to put theplates, if removed from the heat exchanger,NO FURTHER SPACE is required forservicing the PHE.

PLEASE OBSERVE THATThe measurements given in the picture arerecommended by ALFA LAVAL, to providereasonably good working conditions duringinstallation of the heat exchanger as well asfor future maintenance and service. If floorspace is restricted, the dimensions suggestedcan be reduced. It is left to the purchaser to decide just how much access space is required.

Recommended free space foropening and closing.

This field should be kept freefrom fixed installations.

3.4

4”(100mm)

2” (50mm)

Wx1.5 Wx1.5 Wx1.5

3 General

PIPES

Always ensure that no measurable stress isplaced on the heat exchanger by the pipingsystem.

SHUT OFF VALVES

To enable the heat exchanger to be openedwhen necessary shut off valves should be pro-vided on all connections.

PRESSURE RELIEF DEVICES

It is the responsibility of the user to ensure that the required pressure relief devices areproperly installed prior to initial operation. Referto the applicable Code(s) and correspondingStandard(s) for proper size requirements ofthese pressure relief devices.

CONNECTIONS ON THE PRESSURE PLATE(REAR COVER)

Some plate heat exchangers may also haveconnections on the pressure plate. In suchcases, it is important to check against thedrawing or the name plate that the plate packhas been tightened to the right measurementbefore the piping is connected.

Whenever piping is connected to the pressureplate, a short 90o spool piece shall be installedbetween the heat exchanger and the piping.These should be directed upwards or side-ways. This simplifies pressure plate removalduring servicing.

Venting of both sides of the heat exchangermust be provided. This is important and enables air to be drawn from the systemduring start-up. It also enables air or gas to be removed during operation, and it enablesfaster drainage.

3.5

3General

Loose Flanges are provided on certain modeltypes due to interference. When provided theseflanges shall be incorporated into the piping.

MODELS WITH BOTH "S" AND "T" PORTCONNECTIONS

M6-FD, M6-MFD, M6-MWFD, M10-BFD, M10-MFD, M10-BWFD, M10-BDFD, M20-MFD*,M20-MWFD*

MODEL TYPES WITH LOOSE FLANGE ON T PORT CONNECTIONS ONLY:

M6-FG, M6-MFG, M6-MWFG, M10-BFG,M10-MFG, M10-BWFG, M10-BDFG, V28-FD*,V45-FD*, M20-MFG, M20-MWFG

* Loose flange only when design pressuresabove 230 psi.

Notes:1) Sports connections on these model typesutilized industry standard flanges.2) Not all exchangers require T port connections.

PIPING CONNECTION

The loose flange is connected to piping by useof a commercially available stub end of samematerial as the piping.

The stub end is installed as shown and then buttweld to the piping.

3.6

Special Loose Flange Connections

“M” SERIES UNITS:

M3-VG

M6-FG; M6-FD; M6-MFG; M6-MFD; M6-MWFD/FG/FDR/FGR

M10-BFM; M10-BFG; M10-BFD; M10-MFG; M10-MFD;

M10-BWFG; M10-BWFD; M10-BWFGR, M10-BWFDR

M15-BFG; M15-BFD; M15-BFS; M15-MFG;

M15-MFD; M15-MFS; MK15-BWFD; MK15-BWFG

M20-MFG; M20-MFM; M20-MFD; M20-MWFG; M20-MWFD

M30-FM; M30-FG; M30-FD

MA30-FD; MA30-FG; MA30-WFG; MA30-WFD

MX25-BFG; MX25-BFD; MX25-BFS

EC500-WTFE; EC500-WTFL

“V” SERIES UNITS:

V8-VG, V13-FG, V13-FD, V20-FG, V20-FD

4A LIST OF PARALLEL FLOW UNITS

4A.1

“A” SERIES UNITS:

AM10-FG; AM10-FS

A15-BFL; A15-BFG; A15-BFD; A15-BWFG; A15-BWFD

A20-BFL; A20-BFG; A20-BFD

AM20-FG; AM20-BFG; AM20-WFG; AM20-SFG; AM20-DWFG

AK20-FG; AK20-FD; T200-FG; T200-FD

AX30-BFG; AX30-BFD; AX30-BWFG; AX30-BWFD

A35-HA

4APARALLEL FLOW UNITS

FunctionTHE MAIN COMPONENTS OF THE PLATE HEAT EXCHANGER AND THEIR FUNCTIONS.

In ALFA LAVAL Plate Heat Exchangers, heat is transferred from one medium to another throughthin metal plates which have been pressed into a special pattern.

3. CONNECTIONSHoles matching the piping leadthrough the frame plate, permittingthe media to enter into the heatexchanger. Threaded studs aroundthe holes secure the pipes to theequipment. Depending on the application, metallic or rubber-typeLININGS may protect the edges ofthe holes against corrosion.

6. TIGHTENING BOLTSWith the package of thin plateshanging between the frame plateand the pressure plate, a number of TIGHTENING BOLTS are used to press the thin plates together, bringing them into metallic contact,and to compress the gaskets,enough to seal off the narrowpassages which have now been formed between the plates.

8. CHANNEL PLATES

9. GASKETThese plates are called CHANNELPLATES. A groove along the rim of the plate and around the portshold a GASKET, usually made of arubber-type material.

Heat is transferred through the surface which is contained by thegasket, except for some small areasnear the corners.

The number of plates in your heat exchanger is determined by the sizeof the heat transfer surface required.

4A.2

1.2. 3.

4.

5.

6.

7. 8.

9.

1. FRAME PLATE

2. SUPPORT COLUMNThe two bars are suspendedbetween the FRAME PLATE, towhich in most cases the piping isconnected, and a SUPPORTCOLUMN.

4. CARRYING BAR

5. GUIDING BARThe plates hang from a CARRYINGBAR at the top and are kept in line bya GUIDING BAR at the bottom.

7. PRESSURE PLATEThe pressure plate is hung on thecarrying bar and is moveable, as arethe heat transfer plates. In somecases piping may be connected tothe pressure plate.

4A PARALLEL FLOW UNITS

How it works

When a package of plates are pressed together,the holes at the corners form continuous tunnels ormanifolds, leading the media (which participate in the heat transfer process) from theinlets into the plate pack, where they aredistributed in the narrow passages between theplates.

Because of the gasket arrangement on the plates,and the placing of “A” and “B” plates alternately, thetwo liquids enter alternate passages, e.g. the warmliquid between even number passages, and coldliquid between odd number passages.

Thus the media are separated by a thin metal wall.In most cases the liquids flow in oppositedirections.

During the passage through the equipment, the warmer medium will give some of its heatenergy to the thin wall, which instantly loses itagain to the colder medium on the other side.

The warmer medium drops in temperature,while the colder one is heated up.

Finally, the media are led into similar hole-tunnels at the other end of the plates and discharged from the heat exchanger.

4A.3

AB

B

B

A

A

A

S1

B

S2S31

S4

2

3

4

5

A

B

PARALLEL FLOW UNITS 4AHeat transfer

The purpose of the equipment is to transfer heatfrom one medium to another. Heat passes veryeasily through the thin wall separating the twomedia.

The novel pattern into which the plate materialhas been formed not only gives strength and rigidity, but greatly increases the rate of heattransfer from the warmer medium to the metal walland from the wall to the other medium.

This high heat flow through the walls can be seriously reduced by the formation of deposits ofvarious kinds on the wall surfaces.

The pattern of corrugation on Alfa Laval platesmentioned above induces highly turbulent flow.The turbulence gives strong resistance to the formation of deposits on the plate surface; howev-er, it cannot always eliminate fouling.

The deposits may increase the total “wallthickness” substantially, and they consist ofmaterials that have a much lower thermalconductivity than the metal plate. Consequently alayer of deposits can severely reduce the overallheat transfer rate.

The deposits will be considered in the chapter onMAINTENANCE and CLEANING. At this pointwe will only establish that this fouling is unwantedand can under certain circumstances, be harmfulto the heat exchanger because corrosion mayoccur under the deposits.

Pressure dropPressure drops are wasted energy.

All pipe systems and equipment included inthem offer resistance to media flowing throughthem.

Some pressure drop is unavoidable, but for agiven PHE it should be kept as close aspossible to the designed value.

The formation of deposits on the heat transfersurfaces instantly leads to a reduction of thefree space between the plates. This means thatmore energy is needed to get the desired flowthrough the equipment.

It is clear that the fouling of the surfaces isundesirable.

Larger particles and fibers may also be drawninto the heat exchanger and clog the passageways if strainers or other means of protectionhave not been provided for.

A reduced ability by the heat exchanger to holdthe desired temperatures, in combination withan increased pressure drop on any of themedia, indicates that fouling or clogging istaking place.

For corrective action, see MAINTENANCE andCLEANING.

4A.4

PARALLEL FLOW UNITS4A

4A.5

Studying the pictures, you will observe that on a plate hangingvertically, the gasket rests in a groove which includes the heattransfer area

and two corners on theleft side.

OR two corners on theright side.

Smaller rings surround thetwo remaining corners.

We decide that we will name the plates after these two situations.

An A-plate is aplate hanging withthe chevron pointingdownwards.

A B-plate is aplate hanging withthe chevron pointingupwards.

If we turn an A-plate upside down we will have a B-plate:

A B

PARALLEL FLOW UNITS

4A.6

4A

Gaskets

The GASKET is molded in one piece. The material is normally anelastomer, selected to suit the actual combination of temperature,chemical environment and possible other conditions that may bepresent.

The one-piece gasket consists of:1. One field gasket2. Two ring gaskets3. Links

The field gasket is by far the larger partcontaining the whole heat transfer area andthe two corners connected to it. The ringgaskets seal off the remaining two corners.

These three pieces are held together by afew short links, which have no sealingfunction at all. Their purpose is simply to tiethe pieces together and to add somesupport in certain areas. On some plateheat exchangers, the gasket is held in placeon the plate by means of a suitable cementor glue.

2

2

1

3

3


4A.7

Gaskets

As already demonstrated, the two media areeffectively kept apart by the ring and field gas-kets. To prevent intermixing of the media in thecorner areas where field and ring gaskets arevery close to each other, the link pieces have anumber of slots which opens the area betweenthe field and ring gaskets to atmosphere. Anyleakage of media across either gasket willescape from the heat exchanger through theslots.

It is important that these openings are keptclear. If they are not, there is a risk that should aleak occur in that region of the plate, there mightbe a local pressure build-up, which could allowone medium to mix with the other.

Care should be taken not to cut or scratch thegaskets while handling plates.


4A.8

TRANSITION PLATEM30, MX25, A20-B, AM20, AK20, T200, A15-B, M15, M10, M6

Ring Gaskets

Collars (Metal)

Channel Plate Gaskets

Pressure Plate

“A” SERIES UNITS:A10-BFG; A10-BFDAX35-FGA45-FG

“P” SERIES UNITS:P2-FG; P2-VLCH; P2-DWFGP3-E;P3-EH

“M” SERIES UNITS:M3-XVG

“V” SERIES UNITS:V28-FG, V28-FD, V45-FG, V45-FD, V110-FG, V110-FD,V170-FG, V170-FD, V280-FG, V280-FD

List of Diagonal Flow Units

4B.1

4B

4BDIAGONAL FLOW UNITS

4B.2

THE MAIN COMPONENTS OF THE PLATE HEAT EXCHANGER AND THEIR FUNCTIONS.

In ALFA LAVAL Plate Heat Exchangers, heat is transferred from one medium to another through thinmetal plates which have been pressed into a special pattern.

3. CONNECTIONSHoles matching the piping leadthrough the frame plate, permittingthe media to enter into the heatexchanger. Threaded studs aroundthe holes secure the pipes to theequipment. Depending on theapplication, metallic or rubber-typeLININGS may protect the edges ofthe holes against corrosion.

6. TIGHTENING BOLTSWith the package of thin plateshanging between the frame plate andthe pressure plate, a number ofTIGHTENING BOLTS are used topress the thin plates together bringingthem into metallic contact, and tocompress the gaskets enough to sealoff the narrow passages which havenow been formed between the plates.

8. CHANNEL PLATES

9. GASKETThese plates are called CHANNELPLATES. A groove along the rim ofthe plate and around the ports hold aGASKET, usually made of a rubber-type material.

Heat is transferred through thesurface which is contained by thegasket, except for some small areasnear the corners.

The number of plates in your heatexchanger is determined by the sizeof the heat transfer surface required.

1.2. 3.

4.

5.

6.

7. 8.

9.

Function

1. FRAME PLATE

2. SUPPORT COLUMNThe two bars are suspendedbetween the FRAME PLATE, to which in most cases the piping is connected, and a SUPPORTCOLUMN.

4. CARRYING BAR

5. GUIDING BARThe plates hang from a CARRYINGBAR at the top and are kept in line bya GUIDING BAR at the bottom.

7. PRESSURE PLATEThe pressure plate is hung on thecarrying bar and is moveable, as arethe heat transfer plates. In some cases piping may be connected tothe pressure plate.

4B DIAGONAL FLOW UNITS

How it works

When a package of plates are pressed together,the holes at the corners form continuous tunnelsor manifolds, leading the media (which participatein the heat transfer process) from the inlets intothe plate pack, where they are distributed in thenarrow passages between the plates.

Because of the gasket arrangement on theplates, and the placing of “A” and “B” platesalternately, the two liquids enter alternatepassages, e.g. the warm liquid between evennumber passages, and cold liquid between oddnumber passages.

Thus the media are separated by a thin metalwall. In most cases the liquids flow in oppositedirections.

During the passage through the PHE, the warmer medium will give some of its heatenergy to the thin wall, which instantly loses itagain to the colder medium on the other side.

The warmer medium drops in temperature,while the colder one is heated up.

Finally, the media are led into similar hole-tunnels at the other end of the plates and discharged from the heat exchanger.

4B.3

B

B

B

A

A1

2

3

4

5A

S1

B

S2S3

S4

B

A

A

DIAGONAL FLOW UNITS 4BHeat transfer

The purpose of the equipment is to transfer heatfrom one medium to another, and heat passesvery easily through the thin wall separating thetwo media.

The novel pattern into which the plate materialhas been formed not only gives strength andrigidity, but greatly increases the rate of heattransfer from the warmer medium to the metal walland from the wall to the other medium.

This high heat flow through the walls can beseriously reduced by the formation of deposits ofvarious kinds on the wall surfaces.

The pattern of corrugation on Alfa Laval platesmentioned above induces highly turbulent flow.The turbulence gives strong resistance to theformation of deposits on the plate surface; howev-er, it cannot always eliminate fouling.

The deposits may increase the total “wallthickness” substantially, and they consist ofmaterials that have a much lower thermalconductivity than the metal plate. Consequently alayer of deposits can severely reduce the overallheat transfer rate.

The deposits will be considered in the chapter onMAINTENANCE and CLEANING. At this pointwe will only establish that this fouling is unwantedand can under certain circumstances, be harmfulto the heat exchanger because corrosion mayoccur under the deposits.

Pressure drop

Pressure drops are wasted energy.

All pipe systems and equipment included in themoffer resistance to media flowing through them.

Some pressure drop is unavoidable, but for agiven PHE it should be kept as close aspossible to the designed value.

The formation of deposits on the heat transfersurfaces instantly leads to a reduction of thefree space between the plates. This meansthat more energy is needed to get the desiredflow through the equipment.

It is clear that the fouling of the surfaces isundesirable.

Larger particles and fibers may also be drawninto the heat exchanger and clog the passageways if strainers or other means of protectionhave not been provided for.

A reduced ability by the heat exchanger to holdthe desired temperatures, in combination with anincreased pressure drop on any of the media,indicates that fouling or clogging is taking place.

For corrective action, see MAINTENANCE andCLEANING.

4B.4

4B DIAGONAL FLOW UNITS

Plates

4B.5

Studying the pictures, you will observe that on a plate hangingvertically, the gasket rests in a groove which includes the heattransfer area

rings surroundthe remaining corners

and two corners (theupper left-hand cornerand the lower right-hand corner.

OR two corners (the upperright-hand corner andthe lower left-handcorner.

rings surround thetwo remaining corners

Depending on which two corners are included with the heattransfer area, the plate is called an A- or a B-Plate.

An A-plate is aplate hanging with the chevron pointingdownwards.

A B-plate is aplate hanging withthe chevron pointingupwards.A B

DIAGONAL FLOW UNITS 4B

Plates

We can make a B-Plate from an A-plate or the opposite,by changing the gasket and turning the plate upside down.

4B.7

A

B

1. 2. 3.

4. 5.

DIAGONAL FLOW UNITS

4B.8

4BGaskets

The GASKET is molded in one piece. The material is normallyan elastomer, selected to suit the actual combination oftemperature, chemical environment and possible otherconditions that may be present.

The one-piece gasket consists of:1. One field gasket2. Two ring gaskets3. Links

The field gasket is by far the larger partcontaining the whole heat transfer area and thetwo corners connected to it. The ring gaskets sealoff the remaining two corners.

These three pieces are held together by a fewshort links, which have no sealing function at all.Their purpose is simply to tie the pieces togetherand to add some support in certain areas. Onsome plate heat exchangers, the gasket is held inplace on the plate by means of a suitable cementor glue.

2

3

3

1

2


As already demonstrated, the two media areeffectively kept apart by the ring and fieldgaskets. To prevent intermixing of the media inthe corner areas where field and ring gaskets arevery close to each other, the link pieces have anumber of slots which open the area between thefield and ring gaskets to atmosphere. Anyleakage of media across either gasket willescape from the heat exchanger through theseslots.

It is important that these openings are keptclear. If they are not, there is a risk that shoulda leak occur in that region of the plate, theremight be a local pressure build-up, which couldallow one medium to mix with the other.

Care should be taken not to cut or scratch thegaskets while handling plates.

Gaskets

4B.9

DIAGONAL FLOW UNITS4B

TRANSITION PLATEM30, MX25, A20-B, AM20, AK20, T200, A15-B, M15, M10, M6

4B.10

Ring gaskets

Collars (Metal)

Pressure plate

Channel plate gaskets

NON MACHINED PRESSURE PLATE

Sheet Lining

Pressed Collar

Ring Gasket

End Plate

Transition Plate

Rubber Gasket

Sheet Lining, samematerial in metal ring

Metal Ring


4B.11

MACHINED PRESSURE PLATE (AX30, AM20 AND OBSOLETE FRAMES)

Weld

5 Operation

BEFORE STARTING UP FOR THE FIRST TIME OR AFTER A LONG TIME INSTORAGE: MAKE SURE THAT THEPLATE PACK IS COMPRESSED TO THECORRECT MEASUREMENT A! Checkwith the Drawing or Nameplate, which isprovided with each heat exchanger.

It is very important that the system to whichthe heat exchanger is connected, isprotected against sudden and extremevariations of temperature and pressure.This is not only for the heat exchanger butalso for the pipe system itself and everypiece of equipment included in it.

This should be kept in mind whenever amaneuver is to be carried out, includingstarting up of the pumps in the system.

Before starting any pump, check whetherinstructions exist, telling you which pumpshould be started first.

Check that the valve between the pumpand the equipment, controlling the flow rateof the system which you are about to startup is closed.

Check that the valve at the exit, if there isone, is fully open.

START UP

1.

2.

3.

4.

5.1

1.

2.

3.

4.

5.2

Operation 5

5. Open the vent.

6. Start the Pump.

7. Open the valve slowly.

8. When all air is out, close the vent.

9. Repeat the procedure for the other media.

5.

6.

7.

8.

5 Operation

5.3

UNIT IN OPERATION

Any adjustment of the flowrates required tomaintain correct temperatures or pressuredrops should be made slowly, in order toprevent shocks to the system.

Problems in keeping up the performance ofthe heat exchanger may be caused by achange in some of the temperatureconditions, the heat load or by fouling.

SHUT-DOWN

If the heat exchanger is going to be shut down - or if for any reasonthe pumps are to be stopped - the following procedure should befollowed:

As long as the PHE is operating to satisfaction,it should be left without any interference.

1. First establish whether instructionsexist that specify which sideshould be stopped first.

2. SLOWLY CLOSE THE VALVEcontrolling the flow rate of thepump you are about to stop.

3. When the valve is closed, stop thepump.

4. Repeat the procedure for the otherside.

5. Poor quality cooling water may behazardous to metallic materials.Typical examples are corrosion ofstainless steels and nickel alloys.

If for any reason the heatexchanger is shut down for alonger period (more than anumber of days), it should bedrained, and depending on themedia processed, it isrecommendable to rinse and dry it.

1.

2.

3.

5.4

Operation 5

THE RISKS OF NOT COMPLYING WITH THE START-UPAND SHUT-DOWN PROCEDURES.

Valves must be operated gradually. The longerthe pipes and the higher the flow rate, the moreimportant this becomes.

WATER HAMMER is the name given to a shortduration pressure peak, traveling along the pipeas a wave at the speed of sound, and resultingfrom a sudden deceleration of the motion of thefluid in a closed system.

Thus, it is usually related to the shutting down ofa system. However, when starting up a systemwith open valves and empty pipes, the fluid mayburst into some obstacle, like a fine mesh strain-er, a flow meter or a heat exchanger, causing asudden reduction of the flow velocity - if not acomplete halt, and so we may have the conditionsof a Water Hammer.

In the worst case, the pressure surge caused bysuch a sudden stop of the motion of a fluid, canbe several times the normal pressure of thesystem.

Therefore it is very important for the protectionof the whole installation that start-ups and close-downs are carried out with great care.

A liquid in motion in a pipe system represents a lot of energy, and it must be very carefully dealtwith.

Particularly when the fluid is stopped it is imper-ative that this is done smoothly.

NOTE!For this reason fast-closing valves should not beused unless the pipes of the system are veryshort.

6 Opening

Slowly close the valves on theinlets. Shut off the inlet side,

closing the highest pressure first.

Switch off pumps.

Close the valves on both outlets.

If the heat exchanger is hot, waituntil it has cooled down to about40oC (100oF).

Drain

Dismantle any pipe bends connected to the pressure plate, so that it can be moved freely along the carrying bar.

6.1

1.

2.

3.

4.

5.

6.

1. 4.

5.2.

3. 6.

(100oF)

6Opening

Inspect the sliding surfaces of thecarrying bar and wipe clean

Inspect pressure plate roller.

Pull back the plastic covers on thetightening bolts; brush the threadsclean with a steel wire brush.

Lubricate the threads with a thinlayer of grease, e.g LUBRIPLATEFGL-2 or equivalent.

Mark the plate assembly on the out-side by a diagonal line, or numberthe plates in sequence.

Measure and note the dimension A.Compare with code plate and PHEdocumentation for this same serialnumber.

6.2

7.

8.

9.

10.

11.

12.

6 Opening

6.3

13 14(See page 6.5)

13 14(See page 6.5)

13 14(See page 6.5)

13 14(See page 6.5)

3

3

3

2

2

2

1

4

4

1

4

3

2

1

4

M6/M6-MFG & MX25-BFM ONLY HAS ONEBOLT TOP AND BOTTOM

P2 A10B TS6-M AM10 M10BM10M

FG X X X X

FM X

FD X

V8 P3 V13 V28 M10B M10BW M20-MV20 M10M M10DW

E X

FD X

FG X X X X

FM X

VG X

M3 P2 P3 V28 V45

EH XVG X

VLCH XFG X XFD X X

AM20AM20BAM20WAM20S M6

MX25B A15BWA 15B TS20-M AM20DW M6M M15M

FG X X X X X XFD X X XFL XFM X X XFS X

1

6Opening

6.4

M20-M

M20-MFG ONLY HAS ONE BOLTTOP AND BOTTOM

FG

M6/M6-MFG ONLY HAS ONE BOLT TOP AND BOTTOM

FGFDFMFS X

X XX

X

M10B

FD

M10BWM10M

X X

A20B

FD

AK20T200

X X

MX25B

XFLFG

M6M15B AK20 M6MM15F A20B T200 M6DW M30

V110

X X

6 Opening

6.5

NOTE: M30-FD, MA30-FG/FD, MX25-BFS, V280-FG/FDand V170-FD have a twenty bolt or larger pattern, use thispicture only as a guide. Start sequence numbers 5 and 6at the fourth bolt down on both sides.

FGFDHAFS

XX

XX X

MX25B

X

X

X

AX35 A35

AX30BW V110

X

X

FGFD

AX30B

ORDER BOLT NO. TO DIM.

1 1-2-3-4-5-6 1.05A2 1-2-3-4 1.10A3 1-2 OR 3-4 OPENING

If bolts are fitted with bearing boxes loosen andremove them. If not fitted with bearing boxes, thenfollow the pictures above.

Loosen the remaining bolts, alternately and diagonally, to bring length to 1.05A.

Remove bolts 5 and 6 completely.

Continue opening, alternately and diagonally.

Note: Skewing of the Pressure Plate during openingmust not exceed 10 mm (2 turns per bolts) across thewidth and 25 mm (5 turns per bolts) vertically.

13

14

15

16

1615

13 14

13 14

1

4

3

2

1

4

3

2

15

4

36

27 8

AX30B M20M M30AX30BW A45

V170V280

XX

6Removal and insertion of plates

6.6

Brush the threads of the bolts clean,using a steel wire brush

Lubricate the threads with a thin layerof grease, e.g. LUBRIPLATE FGL-2or equivalent.

3. 4.

Push the pressure plate against thesupport column.

Remove the plates. Stack them neatly ona skid or pallet for easy transporting.

Hang the plates with their backs towards thepressure plate (the side without gasket).

REMOVAL OF PLATES

INSERTION OF PLATES

3.

4.

5.5.

1.

2.

6 Closing

Check that all the sealing surfaces (i.e. surfaces in contact with the heattransfer medium) are clean.

Check that the ring gaskets or liners,when fitted in connections, are in position and are in good condition.

Clean and lubricate the sliding surfacesof the carrying bar.

Inspect the pressure plate roller.Remove any debris from top surface ofcarrying bar.

Check against the drawing or flowsheet (provided with each heatexchanger) to make sure that theplates are hanging in the correct order.

Press the plate assembly together.

If the plates are correctly assembled,the edges form a “honeycomb” pattern.

If the plate pack has been marked onthe outside (fig. 6) check this.6.7

1.

2.

3.

4.

5.

6.

7.

1. 4.

2.

7.3.

6.

6Closing

6.8

8 11(See page 6.11)

3

3

3

2

2

2

1

4

1

4

1

4

3

2

1

4

M6/M6-MFG & MX25-BFM ONLY HAS ONEBOLT TOP AND BOTTOM

1

4 2

3

5

6

14 (See page 6.11)

8 11(See page 6.11) 14 (See page 6.11)

14 (See page 6.11)8 11(See page 6.11)

8 11(See page 6.11)

V8 P3 V13 V28 M10B M10BW M20-MV20 M10M M10DW

E X

FD X

FG X X X X

FM X

VG X

M3 P2 P3 V28 V45

EH XVG X

VLCH XFG XFD X X

P2 A10B TS6-M AM10 M10BM10M

FG X X X X

FM X

FD X

AM20AM20BAM20WAM20S M6

MX25B A15BW A15B TS20-M AM20DW M6M M15M

FG X X X X X XFD X X XFL XFM X X XFS X

6 Closing

6.9

M20-M

M20-MFG ONLY HAS ONE BOLTTOP AND BOTTOM

FG

M6/M6-MFG ONLY HAS ONE BOLT TOP AND BOTTOM

FGFDFMFS X

X XX

X

M10B

FD

M10BWM10M

X X

A20B

FD

AK20T200

X X

MX25B

XFL

8 (See page 6.11) 11

4

31

3

2

2

1

4

3

24

1

3

2

1

4

3

24

1

3

24

1

5

6

1

4 2

3

6

5

8 (See page 6.11) 11

8 (See page 6.11) 11

8 (See page 6.11) 11

6

5 14 (See page 6.11)

14 (See page 6.11)

14 (See page 6.11)

14 (See page 6.11)

FG

M6M15B AK20 M6MM15F A20B T200 M6DW M30

V110

X X

6Closing

6.10

Note: See next page for closing instructions for all the models

14

8 11

118

14

1

4

3

2

1

7

3

6

2

5

4

8

1

7

36

2

5

4

1

4

3

28

NOTE: M30-FD, MA30-FG/FD, MX25-BFS, V280-FG/FDand V170-FD have a twenty bolt or larger pattern, use thispicture only as a guide. Start sequence numbers 5 and 6at the fourth bolt down on both sides.

FGFDHAFS

XX

XX X

MX25B

X

X

X

AX35 A35

AX30BW V110

X

X

FGFD

AX30B

ORDER BOLT NO. TO DIM.

1 1-2-3-4-5-6 1.05A2 1-2-3-4 1.10A3 1-2 OR 3-4 OPENING

AX30B M20M M30AX30BW A45

V170V280

XX

8. Place all the bolts that are fitted with bearingboxes in position. If not fitted with bearing boxesthen follow the pictures for your specific model.

9. Brush the threads of the bolts clean, using a steelwire brush.

10. Lubricate the threads with a thin layer of grease,e.g. LUBRIPLATE FGL-2 or equivalent.

11. Tightening is carried out alternately and diago-nally, as shown on the figure above.

12. Check the dimension A during tightening at thepositions of the bolts that are being used. Skewingof the pressure plate during tightening must notexceed 10mm (2 turns per bolt) across the widthand 25 mm (5 turns per bolt) vertically.

13. Nominal plate pack length A can be exceeded inexceptional cases, the tightening can be stoppedat the following dimensions

Plate pack length/plat Plate pack length

> 4 mm A + 1%> 3mm, < 4mm A + 1.5%

14. Place the other bolts in position.• Inspect the washers.

• When fully tightened, the bolts should all beequally tensioned.

• The difference between the plate pack lengthsmeasured at adjacent bolts should not exceed:

2mm when dimension A is < 1000mm

4mm when dimension A is > 1000mm

• The plate pack length at all bolts must not dif-fer by more than 1%

• If the unit does not seal fully, it can be tightenedto the dimension A-1%.

IF DIMENSION A IS NOT REACHED WITH APPLI-CATION OF THE ABOVE STEPS:

• Check the number of plates and dimension A.

• Check that all the nuts and bearing boxes arerunning freely. If not, clean and lubricate orreplace.

• Fit all the bolts, and tighten alternately.

Closing6

6.11

Chlorine as growth inhibitor

Chlorine, commonly used as growth inhibitor in coolingwater systems, reduces the corrosion resistance ofstainless steels (including Hastelloy, Incoloy, Inconeland SMO).

Chlorine weakens the protection layer of these steelsmaking them more susceptible to corrosion attacksthan they otherwise should be. It is a matter of time ofexposure and concentration.

In every case where chlorination of non-titaniumequipment cannot be avoided, ALFA LAVAL must beconsulted.

Contact the following address:ALFA LAVALHeat Transfer Center5400 International Trade DriveRichmond, VA 23231Phone (804) 222-5300Fax (804) 236-3276

NOTE! Titanium is not affected by chlorine.

Mechanical cleaning after opening.

Soft brush and running water.NOTE! Avoid gasket damage.

Chemical cleaning of opened unit byusing:

• Nitric acid

• Sulfamic acid

• Citric Acid

• Phosphoric acid

• Complexing agents (EDTA, NTA)

• Sodium polyphosphates

CLEANING

INCRUSTATION - SCALING

• Calcium carbonate

• Calcium sulphate

• Silicates

High pressure hose.1. 2.

3.

Cleaning7

7.1

Concentration max 4% by wt%Temperature max 140 Fo

2.1.

NOTE!Under no circumstances shouldHYDROCHLORIC ACID be usedwith STAINLESS STEEL PLATESand under no circumstancesshould HYDROFLUORIC ACID beused with TITANIUM PLATES.Water of more than 300 ppmChlorine may not be used for thepreparation of cleaning solutions.

It is very important that carryingbars and support columns made ofaluminum are protected againstchemicals.



Chemical cleaning of opened unit by using:

• Nitric acid

• Sulfamic acid

• Citric Acid

• Phosphoric acid



CLEANING

SEDIMENT

• Corrosion products

• Metal Oxides

• Silt

• Alumina

• Diatomic organisms and their excrement of various colors.


3.

Cleaning

7.2


The addition of surfactants can improvecleaning effect.

4.

1. 2.

NOTE!Under no circumstances shouldHYDROCHLORIC ACID be used withSTAINLESS STEEL PLATES andunder no circumstances shouldHYDROFLUORIC ACID be used withTITANIUM PLATES. Water of morethan 300 ppm Chlorine may not be usedfor the preparation of cleaning solutions.

It is very important that carrying bars andsupport columns made of aluminum areprotected against chemicals.

7



CLEANING:

GROSS FOULING

• Seaweeds

• Wood chips/fibers

• Mussels

• Barnacles


7.3

NOTE: BACKFLUSHING OF THE UNOPENED HEAT EXCHANGERCAN SOMETIMES BE SUFFICIENTLY EFFECTIVE.

1. 2.

NOTE!Under no circumstances shouldHYDROCHLORIC ACID be used withSTAINLESS STEEL PLATES andunder no circumstances shouldHYDROFLUORIC ACID be used withTITANIUM PLATES. Water of morethan 300 ppm Chlorine may not be usedfor the preparation of cleaning solutions.

It is very important that carrying barsand support columns made of aluminumare protected against chemicals.

Cleaning7



Chemical cleaning of opened unit byusing:

• Nitric acid

• Sulfamic acid

• Citric Acid

• Phosphoric acid



CLEANING

BIOLOGICAL GROWTH - SLIME

• Bacteria

• Nematodes

• Protozoa


3.

7.4


1. 2.

NOTE!Under no circumstances shouldHYDROCHLORIC ACID be used withSTAINLESS STEEL PLATES andunder no circumstances shouldHYDROFLUORIC ACID be used withTITANIUM PLATES. Water of more than300 ppm Chlorine may not be used forthe preparation of cleaning solutions.

It is very important that carrying barsand support columns made of aluminumare protected against chemicals.

Cleaning 7

7.5

• Oil residues

• Asphalt

• Fats

CLEANING


Hydrocarbon-based deposits may beremoved by using a soft brush and aPARAFFINIC or NAPHTHA-BASEDsolvent (e.g. KEROSENE).

Dry with a cloth or rinse with water.

NOTE!Gaskets in natural, butyl and EPDMrubber swell in these media.

Contact time should be limited to 0.5hour.

THE FOLLOWING SOLVENTS SHOULD NOT BE USED

• Ketones (e.g. Acetone, Methyletylketone, Methylisobutylketone)

• Esters (e.g. Ethylacetate, Butylacetate)

• Halogenated hydrocarbons (e.g. Chlorothene, Carbon tetrachloride, Freons)

• Aromatics (e.g. Benzene, Toluene)

1. 2.

Cleaning7

7.6

Regasketing

ALFA LAVAL has two types of glue for field repairs - GC11 andGC8 for repairs and exchange of gaskets in plates. A specialglue is recommended for viton and silicone gaskets.

GC11

• A two-component, cold curing epoxy gluewhich gives a strong joint for highertemperatures.

• Future removal of gaskets usuallyrequires heating or freezing of the joint.

• The shelf life is limited to approx. 1 yearwhen stored at room temperature but can beprolonged when kept in a refrigerator.

GC8

• A single-component rubber-based solventadhesive.

• Is normally used for repair work in anuncured condition.

• Can be used for operating temperaturesbelow 200 F

• For operating temperatures above 200° Fand oil coolers/heaters, the glued jointsshould be cured at 200° F for one hour.

• Future removal of the gasket can usuallybe carried out without heating of the cementjoint.

• The storage life at room temperature isabout two years. This period can beextended after checking the glue.

SEPARATE GLUING INSTRUCTIONS WILL BEDELIVERED TOGETHER WITH THE GLUE.

ALFA LAVAL RECONDITIONING SERVICE

In addition to supplying genuine gaskets for yourplate heat exchangers, we are able to provide a“SPECIALIZED PLATE RECONDITIONINGSERVICE” to quickly and efficiently meet yourservice requirements.

Our reconditioning service includes a liquidnitrogen debonding process with chemicalcleaning, crack detection and regasketing usinga special epoxy/phenolic resin adhesive.

This regasketing process requires special ovencuring of the cement to ensure the strongest

possible bond strength between plate andgasket, similar to the process used duringmanufacture. This is one reason why ourservice is guaranteed.

In most cases our reconditioning service hasproved more economical and much faster whencompared with on-site regasketing methods.

For further details, please contact your localALFA LAVAL REPRESENTATIVE.(See Section 1)

7

7.7

7 Regasketing

The Clip-on gasket -a glue-free gasket system

The Clip-on gasket is attached to the plate bytwo gasket prongs which slip under the edge ofthe plate to hold the gasket securely inalignment in the gasket groove.

The prongs are situated at regular intervalsaround the periphery of the plate.

When the plate heat exchanger is thenassembled and tightened, the gasket providesa tight seal around the plate.

The Clip-on gasket in the gasket groove.

NOTE!

Before closing of the equipment:Check that the two gasket prongsare in correct position.

7.8

Regasketing of Snap-On GasketsTHE PROCEDURES (2-7) ARE NOT NECESSARY FOR DOING A SMALL QUANTITY OF PLATES.THESE PROCEDURES WILL INCREASE SPEED OF REGASKETING OF LARGE QUANTITIES OF PLATES.

PREPARATORY PROCEDURES

Pull the old gasket off the plate andclean the groove, if necessary.

Place a flat sheet of plywood (some-what larger than the PHE plate) onthe table.

Place the PHE plate on the boardwith gasket groove upwards and fixfirmly. Placing cylindrical pins in theplank at the carrying bar slots.

Make marks in the plank at all loca-tions for gasket “snap-on”.

Remove the plate.

Drill holes approx. 7mm dia and 10mm deep in the plank at the markedspots.The plank is now a practical toolfor regasketing of larger numbers ofplates.

Replace PHE plate on the board inexactly the same location as at 3above.

1.

2.

3.

4.

5.

6.

7.

5.

6.

1.

2.

3.

7.

4.

7

7.9

7 Regasketing of Snap-On GasketsFASTENING OF THE “SNAP-ON” GASKET

Place the gasket, with the “snap-on”projections downwards, in the gasketgroove.

Place the ring gaskets in the groove andfix them with the T-flap.

Insert the tool point into the recess in theprojection.

Push the projection through the hole in the plate.

Remove the tool point, and theprojection is now “snapped on”.

Repeat for all projections, and thegasket is “snapped on”.

8.

9.

10.

11.

12.

13.

NOTE!BEFORE CLOSING OF THE EQUIP-MENT: CHECK THAT THE T-FLAPSARE IN CORRECT POSITION.

10.13.

12.

11.

7.10

7PARALLEL FLOW UNITS

The End Plate II Gasket is formed by cutting (2) channel gaskets(as shown below) and gluing the gaskets to the first plate.

The (2) half channel gaskets should be glued to the end platewith GC-8 glue: or double sided tape (GC-1). The (4) portgasket areas are critical because these gaskets will be incontact with the process fluids.

+ =

7.11

7 DIAGONAL FLOW UNITS

The End Plate II Gasket is formed by cutting (2) channel gaskets(as shown below) and gluing the gaskets to the first plate.

The (4) parts of the channel gaskets should be glued to the end plate with GC-8 glue: or double sided tape (GC-1). The (4) port gasket areas are critical because these gaskets will be in contact with the process fluids.

+ =

8Fault detection

SYMPTOM

LEAKAGE between plates and frame.

• Relocate gasket.

• remove foreign matter.

• replace connection lining if applicable.

Remove anything disturbing the jointbetween gasket and pressure plate surface.

A perforated end plate must be replaced.

ACTION CORRECTIONS

1.

2.

3.

Mark with a felt tip or similar marker, mark thearea where the leakage seems to be, and openthe heat exchanger

Investigate the gasket condition of the endplate and the connection if applicable, lookfor dislocation, foreign objects, scars andother damage to the gasket surfaces.

Check the plate itself for cracks or holes.

Check the surface of the pressure plate forunevenness, foreign objects sticking to it,etc. that might spoil the joint between thegasket and the adjacent surface.

SYMPTOM

LEAKAGE between flange and frame.

ACTION CORRECTIONS

Disconnect the flange, and look formisalignment between flange andconnection, dislocated or damagedgasket, foreign objects on the surface ofthe gasket or the flange.

• Rearrange the pipe in order to eliminate stress and to correct alignment.

• relocate gasket• replace damaged gasket• replace connection lining if applicable• remove foreign matter from flange

and gasket• reassemble, taking care to avoid

misalignment

1. 1.

1.

8.1

• Relocate gasket.• Re-cement loose gasket, if applicable.• Replace damaged gasket.

A damaged plate must in most cases betaken out for repair or replacement. If it isa regular plate with 4 holes: take the dam-aged plate and the 4-hole plate just in frontor just behind it out of the plate pack. Theheat exchanger can now be reassembledand put back in service PROVIDED THEPLATE PACK IS TIGHTENED TO A NEWMEASUREMENT, WHICH IS EQUAL TOTHE ONE ON THE DRAWING, REDUCEDBY TWO TIMES THE SPACE REQUIREDPER PLATE. CONTACT ALFA LAVAL FORASSISTANCE IN THE RECALCULATIONIF NECESSARY.The small reduction of the heat transferarea is normally of no importance, at leastnot for a short period of time.• Insufficient tightening must be corrected

- see the drawing.

Damaged hanger recesses must berepaired if possible, or the plate replaced.For temporary arrangement with reducednumber of plates - see paragraph 2 above.

Incorrect sequence of plates must be cor-rected (A-B-A-B-..). MAKE SURE THATNO PLATE HAS BEEN DAMAGED,BEFORE REASSEMBLING THE PLATEPACK!

Perforated plates must be replaced. Fortemporary solution, see paragraph 2.

8 Fault detection

8.2

On a Plate Heat Exchanger specially designed for high temperature duties, extremeand sudden temperature drops may sometimes cause a temporary leakage. A typicalexample is a sudden shutting-off of the hot medium flow. The heat exchanger willnormally seal again, as soon as the temperatures of the equipment have stabilized.

NOTE:

Mark the leakage area with a felt tip marker onthe two plates next to the leakage, check andnote the length of the plate pack between insideframe plate and inside pressure plate, and thenopen the heat exchanger.

Check for loose, dislocated or damagedgasket.

Check for plate damage in the area, andalso check plate pack length against thedrawing to see if possible plate or gasketdamage could be caused by overtighteningof the plate pack, or if the leakage itself maysimply be caused by insufficient tightening.

Check hanger recess at both plate ends for deformations, which could causemisalignment between the plates.

Make sure that the plates are hangingcorrectly as A-B-A (see SECTION 4A or4B).

Check for perforation of the plate(corrosion).

ACTION CORRECTIONS

1.

1.

2.

2.

3.

3.

4.

4.

5.

5.

SYMPTOM

LEAKAGE between plates tothe outside.

8Fault detection

8.3

ACTION CORRECTIONS

1. 1.

2.

3.

4.4.

5. 5.

SYMPTOM

LEAKAGE between plates.

Check that the piping is connected to theheat exchanger at correct locations.

Open the lower connection on one side, raisepressure on the other side and by lookinginto the open connection try to detect anyliquid from the pressurized side leaking in,and if so - approximately how far into theplate pack the leakage is located. If noleakage is detected, the reason for the mixingof media must be sought elsewhere. (seeparagraph 5).

If a leakage was detected, note the positionof the leakage along the plate pack and thenopen the plate heat exchanger.

Before starting on the plates themselves,check that the corner areas between the ringand the field gaskets are clear, that theleakage slots are open. This ensures that anyleakage is out of the plate heat exchangerand is to atmosphere. Therefore no pressurecan build up to force the media across thegasket sealing off the other liquid.

If it has not been possible to locate theleakage as described in par. 2 above, it willbe necessary to check each single plate forpossible perforations, using any of thefollowing methods:

• put a strong light behind the plate andwatch for light coming through fine holes or cracks.

• use a magnifying glass to check suspectarea.

• use a chemical penetrant, after havingcleaned the plates well.

Relocate piping to correct connections.

All deposits or material which can blockthe free exit from the area must beremoved. If the leak channels of thegasket have been destroyed, they must bereopened with a suitable tool, or thegasket replaced.

Plates with holes must be replaced. ThePHE may be temporarily operated with areduced number of plates. See “LEAK-AGE between plates to the outside”.

8.4

ACTION CORRECTIONS

1. 1.

1.1

1.2

3.

2.

SYMPTOM

PRESSURE DROP PROBLEMS,

Pressure drop has increased

Check that all valves are open includingnon return valves.

Measure the pressure just before andjust after the heat exchanger, and theflow rate. For viscous media a mem-brane manometer with a diameter of atleast 30 millimeters should be used.Measure or estimate the flow rate if pos-sible. A bucket and a watch showingseconds may be sufficient for small flowrates. For larger flow rates, some type offlowmeter is required. Compare the pres-sure drop observed with the one speci-fied for the actual flow rate. (see plateprint out)

If the pressure drop is higher thanspecified, the temperature programshould also be checked:

If the thermometer readingscorrespond to those specified, theheat transfer surface is probablyclean enough, but the inlet to theheat exchanger may be clogged bysome objects.

If the thermometer readings areNOT corresponding to thosespecified, heat transfer is obviouslydropping below specifications,because of deposits on the heattransfer surface, which at the sametime also increase the pressuredrop, since the passage becomesnarrower.

If the pressure drop corresponds tothe specifications, there is no needfor any action.

If the pressure drop is lower thanspecified, the pump capacity is toosmall or the observation is wrong.

See next paragraph.

Open the PHE and take outwhatever is clogging thepassage, or use the back-flushsystem - if there is one - to rinseout the cloggings.

If a “cleaning-in-place” systemis available, follow theinstruction and use it to washout the deposits. If not, openthe PHE and clean the plates.

See pump instruction manual.

1.1

1.2

2.

8 Fault detection

8.5

ACTION CORRECTIONS

SYMPTOM: HEAT TRANSFER PROBLEMS

The heat transfer capacity is dropping

Measure temperatures at inlet and outletsand also flow rates on both media, ifpossible. At least on one of the media, bothtemperatures and the flow rate must bemeasured. Check to see if the transferredamount of heat energy corresponds to thespecifications.

If great precision is important, it will benecessary to use laboratory thermometerswith an accuracy of 0.2 degrees Fahrenheit,and also to use the best equipmentavailable for flow measurements.

If the heat transfer capacity of the equipmenthas dropped below specified values, theheat transfer surface must be cleaned. Eitheruse the “cleaning-in-place” arrangement ifprovided or open the heat exchanger forvisual inspection and manual cleaning.

NOTE: Contact the Alfa Laval Sales &Service Division for CIP recommendations(See Section 1).

8Fault detection

9 Supplementary Parts

9.1

THE PARTITION PLATE - for special cases only.

If for instance, the thermal program requires that atleast one of the media is to flow in more than onegroup through the plate package, there will be heattransfer plates with fewer than 4 holes.

To prevent the thin metal collapsing under thedifferential pressure, un-punched corners requireextra support.

The extra support is provided by a partition plate -approximately the size of a channel plate - made ofabout 1/4" - 3/4" thick plate material with lined holeswhere a free passage is required.

The partition plate is suspended from the carryingbar. Where partition plates are required, in unitswith 8" ports or larger, there will be one at everyturning point in a multi-grouped plate package.

Example only

ENSR00006 0207

Manajemen Perawatan

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