PQR (combination of GMAW-Short Circuiting and GTAW process) 1

[Mark Chester]

Good Day Experts,

I am preparing a Procedure Qualification Record for the combination of GMAW-short circuiting and GTAW process.
GTAW - for root pass for the maximum of 5.0mm
GMAW - for 2nd pass to copping.
My test coupon (tube) thickness is 8.9mm

My Question is - is this possible for the combination the 2 processes?
- how can I compute and balance the weld metal thickness range of the 2 processes?
since the short circuiting requirement - less than 13mm (x1.1 of the base metal and weld metal)
and for the GTAW is x2 of the weld metal and base metal.
how can I balance the weld metal thickness range and weld metal thickness range?

thanks in advance mga sir.
god bless!

Best Regards,
Mark Chester

 

[Dhurjati Sen]

Dear Mark,

Go for 4 mm by GTAW and rest by GMAW.

So, in the WPS, you can go upto 8 mm by GTAW and then upto 10 mm by GMAW.

You will be below 19 mm so need not include PWHT in the PQR.

Regards.

DHURJATI SEN

 

[david339933]

BM Qualified is limited to 1.1 x Coupon thickness, even when multi-process: It get's a little more tricky when dealing with weld metal qualified....using the max basemetal qualified of 9.79mm (1.1x8.9mm), you could have anywhere from 5.5mm to 9.79mm of GTAW, and 0 - 4.29mm GMAW-S, and any combination in between. How you get the welder to understand this is up to you.

BPV Section IX
Edition/Addenda:
Para./Fig./Table No:
Subject Description: Section IX, QW-403.10, Short-Circuiting Mode
Date Issued: 09/24/1996
Record Number: BC96-001
Interpretation Number : IX-95-33
Question(s) and Reply(ies):
Question: Does QW-403.10 limit the base metal thickness qualified to 1.1T for a combination GMAW-S/SMAW PQR test coupon thickness "T" less than ½ in. when used to support a combination GMAW-S/SMAW WPS?

Reply: Yes.

 

[weldstan]

A star for david339933