Thanks for your reply,
i know to use API661 to design an Aircooler,but my question is different.if i consider 2times or 3times of alloawable nozzle loads(acc.to API) i will have problems or not?
farzam,
I do not see the problem in case of nozzle can withstand 2 (or 3 times) of allowable load from API 661. The problem may be higher cost of construction.
What is the specific reason to use 2 or 3 times of nozzle load? Is this the problem from piping design?
I would suspect that you will have problems if you design your piping system to hit the nozzles with 2-3x API-661 allowables and they are only designed for 1x. At the very least, you are going to have to submit those loads to your vendor for approval. At a minimum, there will probably be a cost adder to beef up the nozzles.
In general, we call for 2x API-661 as a part of all our purchase specs for air coolers as the 1x are typically too low to be useable for multibank arrangements. For a single bay cooler, I find I can usually make 1x 661 work out.
Edward L. Klein
Pipe Stress Engineer
Houston, Texas
"All the world is a Spring"
All opinions expressed here are my own and not my company's.
You most likely to encounter problems for 1xAPI loads, as they are typically too low. 2x or 3x would usually increase the cost of exchanger, however, is far less expensive than a complex piping design, particularly for a compact, modulised system, increasingly popular in the modern petrochemical industry.
