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Plate

& Shell

PECPL has partnered with German company GESMEX for the manufacture and supply of plate & shell heat exchangers . These heat exchangers are extensively used in oil & gas and other process industries . Under our partnership agreement , Gesmex will continue to manufacture the plate assembly – its core competency – and Precision will manufacture the shell and complete the final assembly at its Chennai facility .

By Vijay Chakravarthy ( Precision Equipments Ltd .) and Mike Hallmann ( GESMEX )

100 % 90 % 80 % 70 % 60 % 50 % 40 % 30 % 20 % 10 % 0 %

Surface Area

The plate & shell configuration offers many important advantages over the conventional shell & tube . Those who have switched over to the plate & shell configuration often react by asking : “ How come we were not aware of this choice before ?” or “ why did we not know about this earlier ?”. In this short article we will explain or provide : 1 . A basic description of plate & shell with sub component views 2 . Current market applications 3 . Advantages of plate & shell over conventional shell

& tube

Basic description of plate & shell A basic sketch of plate & shell is shown in Fig . 1 and a cut-away view in Fig . 2 . From both these figures it can be seen that :

• Circular heat exchanger plates are arranged as a pack to form flow channels .

• The warm and cool streams flow through alternate channels mostly , counter-current

• Heat transfer takes place through the walls of the plate channels

• The plate channels are separated by highly reliable laser-made welds

Shell- & -tube Shell- & -plate

Cost ( USD )

Figure 2 : Comparison of critical design parameters and cost - Shell and tube vs Shell and plate

Figure 1 : Plate and shell basic configuration

• Plates are welded alternately on the outer circumference and on the edges of the plate openings

• Appropriate ports are provided in the plate pack for the channel side and shell side streams to flow through the plate pack

USPs as a result of GESMEX laser welding technology advantages If you were to reflect on your past experiences , what is the weakest point of a welded heat exchanger – for shell and tube as well as all types of welded PHE ? Your likely conclusion will be that it is the welds of either the tube-totubesheet or circumferential on exchanger plates . That was our initial driver . Over a period of two years , GESMEX and the German company Trumpf developed a special laser welding technology , able to create weld seams with a unique cross-sectional area . In fact , that area provides up to 3.5x the thickness of the heat transfer plates alone . Thanks to this development , the plate welds are no longer the weakest points of the heat exchanger design . Since the plate material became the weakest point , working out how to improve reliability of heat exchangers for demanding applications became predictable instantly . Now the focus could be set on material thickness , material grades , alloy structure , etc . In Figure 3 you can see the deformations that GESMEX laser welded plate packs are able to withstand during burst pressure testing , performed continuously . The welding machine resulting out of the original inventions was installed in year 2008 . Last year , a second Laser welding center was taken into operation that consist of all the original advantages as well as additional 14 years of shell & plate manufacturing and operational experience of > 3,000 heat exchanger .

24 Heat Exchanger World April 2023 www . heat-exchanger-world . com