caper656
Mechanical
- Dec 7, 2017
- 26
Recently had a request to replace a pressure vessel. It is made of RMT A-500 Gr B, relatively low pressure, welded end caps, non-code BUT specification sheet shows -20F MDMT. Now technically speaking, since its not code, there is no requirement for impact testing...or in addition, there is no additional customer request that the material be impact tested to a certain Joules. Therefore...technically...someone could supply an RMT A-500 GR B Pressure vessel that's noncoded and rated to -500F(exaggerated) with 0 Joules impact value? Since no code and no material code book references A-36/A500 as a impact tested material, theres no designation of Joules for an impact test that it has to meet. In addition, Im curious if its even practical to list MDMT on a material that has no code designation. Even if I listed +20F on a nameplate/Spec Sheet, I would think it would need "MDMT: +20F with 89ft/lb Impact Testing" or some disclaimer. That of course is considering how you correlate Impact test results with yield strength reduction
This is more of an exercise of industry understanding.
This is more of an exercise of industry understanding.
