AWS D1.6 Procedure Qualification

By bennett149 Date 12-24-2014 16:56

I'm working on several D1.6 PRQs with unlisted base metal. I find the qualification section of D1.6 fairly vague, especially when it comes to essential variables of the electrical parameters of Table 4.1.

My ultimate question is should I weld the PQR coupons using a range of parameters (example: 25-27 volts, 200-300 amps) based on manufacturer’s recommendations as a guide, or should I weld the PQR coupons at one setting (example: 26 volts, 250 amps) and apply the prequalified essential variables when writing my WPS? My goal is to produce a WPS with a fairly broad range of parameters and not be limited to a narrow range.

I'm not sure why I'm having such an issue with this but any help is much appreciated. If only it were as easy as ASME.......... Thanks in advance.

By 803056

Date 12-26-2014 21:13

If you have unlimited resources and a lot of time, go for the gold. If you are working within time and money constrains like most of us, weld the coupon using the welding parameters that provide acceptable test results. Write the WPS using the ranges allowed by the applicable welding standard.

One way of establishing the welding parameters is to run several T-Fillet Break tests and use the parameters that product the best fillet weld results. Read the welding standard carefully, most require the fillet welds, one being the largest single pass fillet, and one the smallest multiple pass fillet weld to be used in production, to be qualified separately from the grooved joint. Once the parameters have been established for the fillet welds, use those parameters to qualify the groove weld.

Best regards - Al