A335 P22 A335 P22 matengz (Materials) (OP) 29 Apr 17 08:57 in accordance to ASME SEC IX QW-431. can we do a PQR using ER70S-6+ E7018-1 to weld A335 P22 IF PWHT NOT REQUIRED. RE: A335 P22 metengr (Materials) 29 Apr 17 13:39 Yes, you can. RE: A335 P22 weldstan (Materials) 30 Apr 17 14:47 While you can do so, why would you unless you were welding P22 to carbon steel? Generally P22 is used at temperatures above the useful range of carbon steel or in corrosion service that would lead to rapid, potentially catastrophic failure. RE: A335 P22 metengr (Materials) 30 Apr 17 16:00 Agree with stanweld. However, there have been applications where blow down/drain lines have transitioned from P22 to carbon steel because of erosion concerns up stream.