3 replies to this topic

[chem101]

HI:
Can we use pipe/ pipe exchanger in gas application?I am trying to size shell and tube exchanger for gas application but i get allot of pressure drop. Is there any one who can explain me the application of pipe/pipe exchanger?
Thank you very much.
your response is appreciated.

please elaborate your problem and I promise I will help

Manan

[ankur2061]

HI:
Can we use pipe/ pipe exchanger in gas application?I am trying to size shell and tube exchanger for gas application but i get allot of pressure drop. Is there any one who can explain me the application of pipe/pipe exchanger?
Thank you very much.
your response is appreciated.

chem101,

What you are referring as pipe/pipe exchanger is commonly called as 'Double-Pipe Heat Exchanger'.
I prepared a specification titled 'Process Design Criteria' for a middle-east O&G company where a section deals with Double-Pipe HEs. I am quoting verbatim from what I have written in the specification:

Double-Pipe Heat Exchangers

a. Double-pipe heat exchangers shall be used wherever justified for economic or space reasons. Double pipe heat exchangers are widely used where total heat transfer surface is small, typically 100-200 ft² or less. For heat exchangers where thin walled tubes are used, these shall be of one continuous length without welding.

b. Double pipe heat exchangers shall be designed such that maximum flow of fluids will not cause vibration that may cause damage to pipes and return bends.

c. Double pipe heat exchangers shall be assembled in 12, 15 and 20 ft effective length; effective length being distance in each leg, over which heat transfer occurs and excludes inner pipe protruding beyond exchanger section.

d. Over all Heat transfer Coefficient shall be calculated for each double pipe heat exchanger depending on the nature of fluid flowing inside the tube and fluid flowing in the annuli on case-to-case basis.

e. LMTD for double pipe heat exchanger shall be calculated considering counter current flow.

f. Reference is made to “BP standards RP 26-1” and “Process Heat Transfer” by D.Q Kern Chapter 6 “Counter Flow Double Pipe Exchanger”.

This will give some overview of Double-Pipe Heat Exchangers to you.

Regards,
Ankur.

[chem101]

Thank you very much Ankur for you help.