Wrong applying WPS

Date 03-09-2018 05:33 Edited 03-09-2018 14:02

Where is supervision and QC while this is happening? Who directs the welder to use the appropriate WPS? That is the managements responsibility!

After the floggings are over, and there are a number of people that need to be flogged, one would have to review the two WPSs to see what the differences were. I can imagine the following if the welder followed the WPS for P1 to P4:

Filler metal - matching the lower strength steel, may be the same as that listed by for P1 to P1. Hopeful the P1 to P4 required low hydrogen practices, where as P1 to P1 may not depending on the welding process.
Preheat - higher than that required by the WPS for P1 to P1
Technique - higher preheat and controlled heat input for the P1-P4, where lower preheat and uncontrolled heat input for P1 to P1

Bottom line; could be there may be no problem, if the Gods were smiling that particular day.

Al

By Duc Date 03-09-2018 08:27

Thank very much 803056

By 803056

Date 03-13-2018 07:13

I just reread the original question. They did not follow the WPS for P1 to P4, they followed a WPS for P1 to P1. In fact they should have been following the WPS for P1 to P4.

- The filler metal may be acceptable if they matched the strength of the P1 and used a technique to ensure a low hydrogen deposit.
- The P4 typically requires higher preheat than P1, so there is the possibility to develop an undesirable microstructure in the HAZ of the P4.
- The interpass temperature of the P4 may be limited whereas it may not be for the P1.
- Was PWHT required?
- Was the procedure qualified for CVN?

The bottom line is you need to compare the two WPSs to see what the differences are. There may be "minor" or they could be "major" issues or differences between the two WPSs.

Sorry if I gave you a false sense of comfort with my first response.

Al