TEMA vs ASME

[M. Ali]

Dear All,

For many medium pressure refinery services, the minimum thickness for
shells of heat exchangers come out to be lesser than minimum limits
prescribed by TEMA 'R'.
My question is, "Should TEMA be used for inservice inspection and
evaluation or is it just a manufacturing code?"

Regards,

M.Ali

[JASPAL SINGH]

In hierarchy of standards - TEMA was always in a position of a
recommendations standard, not a construction code.
Manufacturer is obliged to it only when it been agreed with client.

TEMA was never a construction design Code except tubesheet design
earlier. Now Tubesheet design is also covered in ASME UHX Part. So
when design code is ASME, then tubesheet must be designed per ASME UHX
Part. However, if client insist then you may have to design tubesheet
for both the Codes and take conservative thickness.

Irrespective of tubesheet design, TEMA covers so many other
requirements and recommendations for various TEMA classes R, C, B
exchangers in terms min. shell thk, boltings, gasket width, tube
bundle requirements etc. So TEMA still have a lots of importance.

Thanks.

Jaspal Singh
Quality Assurance
ISGEC-YNR
9996624244