Acceptance Standards for using ammonium persulfate

[Jman69]

Does anyone know where I may be able to find some acceptance criteria for using ammonium persulfate on arc burns on pressure vessel per ASME Code. I did find in Section 8(Nonmandatory Appendix K)directions for thier use, but not sure what results are acceptable.

Thanks, John

 

[stanweld]

There is no acceptance criteria per Code. The objective of the etch is to verify that the melted/resolidified zone and HAZ have been eliminated; i.e., there is no color change from the untouched base metal thru the area of the removed arc burn.

 

[Jman69]

Gottcha. Thanks so much Stanweld.

 

[Fizza453]

Almost same rules are also contained in QW-470 of ASME Section IX.

Nasir
Welding Engineer
DESCON ENGINEERING LIMITED
PAKISTAN