Microeng ASME Sec VIII Div. 1 - Please read code rules from : UHA 31 using Fig 5 - UCS-28.2 - Appendix 5 gives examples for application for formed heads and this will have to be applied. UHA 32 requirements for PWHT - specified in Table UHA 32 except for exemptions in Notes to Table UHA 32. For P 8 grade materials, yes generally speaking no PWHT is mandatory. Depending on the strain on formed heads and the application of strained vessels of P 8 grade materials with > 20% in corrosive services, users and process licensors / fabricators may decide to PWHT or do stress relief anneal if the formed head or the welds are susceptible for SCC or strain related cracking in corrosive environment. ASME Code Sec VIII Div 1 may not give this directly. With strain > 20% formed heads even for P 8 may have to be given PWHT to reduced strain related damages. Probably you can refer to some code cases also to get more input on specific cases. Hope this helps C.V.Srinivasan Nishi Engineers Pvt Ltd India May 15, 2009 E-mail: nishi@vsnl.com >I have the question, I can not find the postfabrication >strain limits and required heat treatment for the Material >SA-240 316L or SA-240 304L, for example, I purchased a >austenitic stainless steel plate, I want to form it into >head, I can calculated forming strains, but it looks no any >use because I can not find any requirements in the Table >UHA-44 for the Heat treatment, Is it no any requirements for >this material of the forming strain limits? Thank you a lot >to explain in advance.