Did you used oxygen analyzer during stainless steel welding (SS, DSS, and/or SDSS) ?

If yes, some spec/standards said maximum 500ppm oxygen content (DEP, Total) before start welding, other have stringent requirement such as maximum 100ppm before start weld, and 200ppm during welding. More than 200ppm shall stop (Petrobras).

#stainlesssteel#stainlesssteelweld
#sdss#oxygenanalyzer

Snipshot various client specification heat input control on SDSS welding

DEP welding standard
Table-11
When impact or corrosion testing is required a change exceeding ±25 % of the average heat input for a weld zone measured during procedure qualification welding

Petrobras
Table-6
t < 7mm >> 0.5 to 1.0 kJ/mm
7 < t ≤ 20 >> 0.7 to 1.2 kJ/mm
t > 20 >> 1.0 to 1.5 kJ/mm

API RP 582
11.3.2.2 The heat input shall not exceed the maximum used during procedure qualification. The minimum heat input qualified shall be the higher of 0.5 kJ/mm (12.7 kJ/in.) or 50 % of the maximum used on the PQR. See ASME BPVC Section IX, QW-409.1(c) and Appendix H for waveform-controlled welding.

Now, we need to run PQR to meeting any standards requirements in order to save cost and time. #SDSS

Destructive Test by Bend Test required for weld overlay welder.

Some material and process also cannot qualified by RT. Will post this another day . #weldertest
#asmeix
#welder

some says, pareto principle 80/20

For piping projects, in order to provide qualified welder with qualified range of material, diameter, and thickness we can qualified them with 3 number of CS test coupon only.

This small number of test coupon will be covered mostly material type/grade, diameter, and thickness range.

You may check below combination:

1) TP-1, A106-Gr-B, Pipe 2-1/2″ Sch XXS, GTAW+SMAW, 6G uphill

2) TP-2, A106-Gr-B, Pipe 2-1/2″ Sch XXS, GTAW, 6G uphill

3) TP-3, A106-Gr-B, Pipe 1/2″ Sch XXS, GTAW, 6G uphill

#projects#weldertest#welder
#piping

For 1/2″ pipe test coupon we need at least 3 set of coupon to capture 6″ effective weld length for visual then shoot for RT (if allowed by material and process as per code) otherwise send for destructive test. #WQT, #ASMEIX