ASTM A216 EWCD

[boofi]

Hey y'all, hope everyone had a good holiday.

I'm looking at an exchanger made in 1943. The body flanges are A216 GR EWCD according to the drawing. I can't find this grade anywhere; not even on Google! I have the ASME Sec VIII code from 1943 that has A-216 cast steels grades WCA and WCB. but no others. I'm looking for the allowable stress to perform a minimum thickness calculation. WCA allowable stress up to 650ºF is 12000psi, and WCB allowable stress up to 650ºF is 14000psi. Anybody have any ideas for A216 grade EWCD? Thanks!

 

[metengr]

My 1952 edition of ASTM material specifications references markings on finished products with either ASTM WCA or WCB or using the Standard Marking System for Valves, Fittings, Flanges and Unions SP-25-1936.

 

[boofi]

Thanks metengr. I tried looking up MSS SP-25 but I couldn't find anything for EWCD. What I ended up doing was using a material test record for another exchanger that was part of the same project. That had the ultimate strength values for the flanges that had the same metallurgy and grade. Then I used the safety factor of 5 to get an allowable stress that landed me close to, but slightly higher than the allowable stress for A216 WCB from the 1943 ASME code.

 

[metengr]

Very good. I would use the allowable stress for A 216 Grade WCB being slightly lower because it is easier to defend a lower allowable stress based on conservatism.