plate heat exchanger maintenance

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A Guide to the Comprehensive Maintenance Program for HISAKA Plate Heat Exchanger ... Plate Heat Exchanger is high-performance and trouble free but …
PLATE HEAT EXCHANGER

……

MAINTENANCE

Plate Heat Exchanger is high-performance and trouble free but …… Periodic maintenance is necessary to secure the operation.

A Guide to the Comprehensive Maintenance Program for HISAKA Plate Heat Exchanger

Watch the operating condition :  Leakage of fluids due to deterioration of the gaskets  Decreasing thermal performance due to depsoits and fouling on plate surface Corrosion, cracks and pinholes Corrosion may occur to used plates causing pin-holes or cracks. This will result in fluid leakage or intermixing of the two fluids.

 Intermixing of the fluids due to corrosion, crack and

For Maintenance call.

+81-72-966-8910 Tokyo…TEL.+81-3-5250-0760 ASEAN…TEL.+60-3-5621-8588

pin hole on the plates

Osaka…TEL.

[ Maintenance call sticker This sticker which is labeled on to each unit shows our "maintenance calls".

Guide bar support

Professional maintenance work can prevent :  The deformation or damage to plates by un-

aPlease inform the manufacturing (MFG) no. of the unit

reasonable opening and tightening

E-frame

 Insufficient cleaning of plate

Upper guide bar

Basic Construction of a PHE a A PHE is basically made up of heat transfer plates that are press-formed from thin sheets of corrosionresistant metal such as stainless steel or titanium. A sealing gasket is applied to each plate and it is then suspended onto an upper guide bar before it is tightened to the correct dimension.

 Tiny corrosion, crack and pin holes of the plates may be overlooked

S-frame

english/ Malaysia : HISAKAWORKS S.E.A. SDN. BHD. Lot 4882, 5 Japan SS 13/2, 47500 Subang Jaya, Selangor Darul Ehsan, Malaysia Phone: 60-3-5621-8588 Fax: 06-3-5621-7588 China : HISAKA (SHANGHAI) COMMERCE CO., LTD. 699 West Nanjin Road, Shanghai 200041, China Phone: 86-21-5211-0701 Fax: 86-21-5211-0720

Hot side inlet Cold side outlet

Overall heat transfer coefficient [W/m3]

Changing of overall heat transfer coefficient

Lower guide bar Gasket Hot side outlet

Plate

Cold side inlet

7,000 6,000 5,000 4,000 Design 3,000 2,000 1,000 0

Tightening bolts and nuts

Baseplate

Maintenance

Thermal performance will be decreased as time goes on by deposit and fouling on the plate after long time operation.

Operating time

HE-CE000302 10.10. − .SAN ●

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HISAKA’s PHE maintenance program ensures top performance and lasting trouble free use

A wealth of maintenance options giving reliable support

"Full Service Package" As a leading supplier of Plate Heat Exchanger (PHE) in the world, HISAKA offers professional maintenance service program that maintains the PHE performance over the product's life cycle ensuring the satisfaction of our customers. Our core maintenance program, "Full Service Package", provides multifaceted support to achieve optimum condition of the units at site. "Full Service Package" offers a comprehensive maintenance program to restore the original performance at HISAKA authorized  Disassembly : After visual inspection of the PHE, the unit is disassem ess of the plates while the frame is given an overhaul.

service facilities. This program consists of plate cleaning, gasket replacement, dye penetration test, re-assembly and final inspection before shipping. We can offer the maintenance program to match various operating conditions, enabling operation to be sus-

 Disassembly : The overhaul of frame is important to secure the plates firmly. Inspecting the connection parts and replacing the stud bolts & nuts, etc., if they are damaged.

 Soaking in degreasing tank : The old gaskets with adhesive residue on the gasket groove are removed after soaking the plates in the degreasing tank.

 Cleaning : The plates are soaked in a cleaning chemical tank to remove the scale, sediment and dirt on the plate surface and finally washed away with water jet.

 Gluing the gaskets : After cleaning the plates, new gaskets are glued to the plates. At the same time, we ensure the new gaskets are firmly adhering to the groove in the correct position.

tained in many processes.

 Assembly : Now that the maintenance is completed, the plates are mounted onto the frame, which has been overhauled separately. The plate arrangement and the seal line of the plates are carefully checked.

 Tightening the plates : Using a tightening device for PHE, the plate pack is tightened to the correct dimension. The dedicated tightening device can handle large number of plates in a short time.

Leak Test : After tightening, the unit is tested by air to ensure no leakage between plate channels. This leak test confirms all plates are defect free. (DPT inspection is an option)

Basic flowchart of "Full Service package" for Hisaka Plate Heat Exchanger

cCertified sticker after "Full Service package" After completion of "Full Service package", the certified sticker is put on the unit. Maintenance data is registered in the Hisaka data base with serial number on the sticker.

It is difficult to detect tiny holes caused by pitting and crevice corrosion on the plate’s surface without professional skill and experience. The Dye Penetrant Test checks these defects for the penetration through the plate. The Dye Penetrant is applied to one Arattaro, our side of the plate, and coating the other side promotional charactor with the developing fluid. The penetration can be found easily by DPT.

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3 ––– On site Servicing

●Maintenance for plates… In the event that "Full Service Package" is not applicable, we can offer plates only cleaning and reassemble service after cleaning.

●On site maintenance…Our specially trained and experienced staff will provide full maintenance service at site. We provide comprehensive and skillful support to any maintenance program to be performed.

●Maintenance service by contract… By periodical maintenance service contract, defects of the unit can be detected earlier. Therefore, accidents and unscheduled operation stoppage can be avoided.

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Final Inspection : Upon completion of all the above maintenance processes, the unit is pressure tested hydraulically to ensure no leakage from the unit. After the final inspection, a certified sticker is put on the unit.

b Test record After "Full Service package", a set of maintenance report is sent to the owner. ●

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OPTIONS

Spare parts stock… The spare parts such as plate, gasket, tightening bolt & nut, rubber boot, nozzle, etc. are prepared.

●Plate rotation… The plate rotation service replaces used plates with new plates kept in our factory. This reduces downtime and quick restart of operation due to shorter time required for PHE maintenance.

2 ––– Upgrade service

Dye Penetrant Test (DPT) inspection (Liquid Penetrant Examination)



1––– Cleaning service

●"Slit-in" gasket…There are two types of gaskets, i.e. glued type and glue-free type called "Slit-in". Although the glued type provides robust adhesion strength but the "slitin" glue-free type is easier to install/ remove the gaskets. Replacing "Slit-in" gasket is less time consuming, it is shorter only 1/10 of the time to replace than the glued type.

Estimation of allowable operating perssure Allowable operating pressure MPa

PLATE HEAT EXCHANGEER MAINTENANCE

Automatic tightening device… In order to carry out the opening and tightening work of larger units easiliy, a dedicated pneumatic tightening device shall be recommended. Uniform tightening can be correctly performed to the unit.

1.4 1.2 1.0 0.8 0.6 0.4 0.2 0

5    10  

15  

Compression ratio

The existing PHEs in the plants can be replaced with "Slit-in" type or slits can be made to the existing PHEs. ●Monitoring of plates and gaskets… Although plates is made of corrosion resistant material, defects such as pin-hole or crack may occur on the plates depending on the operating conditions. Through our "Monitoring Service", any defects such as plate corrosion, changes in plate thickness and gasket deterioration can be detected and reported.

20    25

ε%

There is a linear correlation between the compression ratio of gasket and the operating pressure. The allowable operating pressure can be estimated by compression ratio, which can be calculated by the following equation : – Tightening dimension of gasket ×100 ε= Measured thickness Measured thickness



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Cleaning-in-place (CIP) Unit… Mobile CIP unit. By circulating the cleaning chemicals through the unit, the deposit on the plate surface can be removed without disassembly.