Question
If a system is subject to one displacement range from ambient to -100 F cycling 7000 times and a second displacement range from ambient to +500 cycling 2000 times how is the equivalent cycle (N) calculated for use in the specification for "f" in the displacement range case -100 to 500...
bvi
Thanks for the reply.
Is there a reason (that I am missing) as to why the "least [Ea}" value of the modulus is used for the stress calc in cryogenic service?
I would have the contractor check the dies he is using to cut & thread the pipe joints.
It wouldn't be the first time a die was used without the correct taper (or none at all like conduit)
Hello All
I am having difficulty understanding the proper interpretation of section 319.2.2(d) in cryogenic services.
If there is material variation or a temperature variation within the piping system, the B31.3 code requires (where significant impact to stress is anticipated) the use of the...
metengr
Thanks for the reply
I need to expand further on the issue and I should have been more specific. !!!!!
What I am having difficulty understanding is the proper interpretation of section 319.2.2(d)
Here's the scenario as I see it assuming there is material variation or a temperature...
How to interpret the B31.3 code
For Cryogenic service should the Emin value of Youngs Modulus be used for the calculation of forces and the resulting stresses
OR
Should the calc be performed using Ea as installed with the stresses magnified by the ratio of Em/Ea (not Ea/Em as in hot service)...
