Impact testing
Impact testing
(OP)
ASME UG 20(f) (3)impact testing is not mandatory between -29ºC & 345ºC. Is there an exemption to mandatory test above 345ºC? We have a vessel of design pressure of 2.77MPa & design temp of 350ºC. Material grade for shell & nozzles is ASTM A106B.





RE: Impact testing
Typically that grade of carbon steel can be used up to 426C, but can be subject to damages such as creep / graphitization /etc. Also you will have a noticeable depreciation in strength at elevated temperature.
What service would this vessel be in?
RE: Impact testing
Vessel is a steam distribution header operating at ambient up to 350ºC. Pipe wall thickness is Sch.40 (10.3mm).
Low temperature operation is not a consideration.
I am trying to establish what if any requirements are for operating at this temperature as UG -20 mentions upper limit of 345ºC. for non mandatory impact testing
RE: Impact testing
It's pretty straight forward at this point. You exceed the temperature limits of UG-20(f) for operation down to -20F (-29C) with out impact testing. Have you reviewed UCS-66 yet? It may also provide a path for impact test exemption as you state that low temp operation is not anticipated.
Joe Tank
RE: Impact testing
RE: Impact testing
RE: Impact testing
RE: Impact testing
my 2 cents
RE: Impact testing
Regards,
Mike
RE: Impact testing
Thanks.