WPS same P N° different Group N° WPS same P N° different Group N° JATE (Mechanical) (OP) 6 Jan 17 18:50 Hello: I have a WPS qualified with impact, the rating was made with a material Pn ° 1 Group 3, Do I can weld a material Pn ° Group 1 ? Thanks for your help Juan RE: WPS same P N° different Group N° metengr (Materials) 6 Jan 17 20:14 Not for impact qualification. You need a WPS qualified for Group 1. RE: WPS same P N° different Group N° Don56 (Mechanical) 9 Jan 17 22:28 If impact testing is not required you an weld any P#1 material regardless of the group number. Group numbers only apply when impact testing is required. RE: WPS same P N° different Group N° JATE (Mechanical) (OP) 14 Jan 17 13:00 Mr. Metengr: can you helpme Where I find the indicated , I'm looking at ASME IX but I can not find it. Thanks for your help JUAN RE: WPS same P N° different Group N° metengr (Materials) 14 Jan 17 14:24 Please see 2015 ASME Section IX. Notch toughness is impact testing QW-200.3 To reduce the number of welding procedure qualifications required, P‐Numbers are assigned to base metals dependent on characteristics such as composition, weldability, and mechanical properties, where this can logically be done; and for steel and steel alloys (Table QW/QB-422) Group Numbers are assigned additionally to P‐Numbers. These Group Numbers classify the metals within P‐Numbers for the purpose of procedure qualification where notch‐toughness requirements are specified. So to weld P-No 1 Group 1 to weld to P-No 1 Group 3 for impact qualification, you need a P-No 1 Group 1 to P-No 1 Group 3 WPS.