Thursday, September 8, 2011

RE: [MW:12378] Welder Qualification for MIG welding(Short-circuiting transfer)

Hi Prasu,

Short Circuiting transfer involved the lowest range of welding currents. It produces a small, fast freezing weld pool. Weld metal is only transferred from the electrode to the work piece only when the electrode comes into contact with the weld pool (Circuit completed). As soon as the electrode melted and broke off, the circuit is broken and there is no metal transfer across the GAP.
These process of short circuiting and the use of low current system introduces a major defect like, lack of fusion (side wall or inter run). These lack of side wall fusion might not be clearly define in Radiographic films so the use of Bend test is to show if the defect exist upon stressing the joint.

Regards,

Rems Okonkwo
Welding Engineer
Nigerdock Nig. PLC-FZE
Snake Island Integrated Free Zone
Apapa, Lagos, Nigeria
Mobile: +234 (0) 806 330 5867
+234 (0) 1 660 1514
Email: rems.okonkwo@nigerdock.com
Web Site: www.nigerdock.com

-----Original Message-----
From: Prasu Cutie
Sent: 08/09/2011 6:15:20 am
Subject: [MW:12371] Welder Qualification for MIG welding(Short-circuiting transfer)

Dear Experts,

As per ASME Sec-IX, Welder qualification for MIG welding(Short-Circuiting
transfer) testing must be done by Bend test only rather than RT or UR like
for other mode of transfers.
What could be the exact technical reason behind this requirement??????
Can any body explain me at the earliest please!!!!

Regards
Prasu

--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding+unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.

--
To post to this group, send email to materials-welding@googlegroups.com
To unsubscribe from this group, send email to materials-welding+unsubscribe@googlegroups.com
For more options, visit this group's bolg at http://materials-welding.blogspot.com/
The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.

No comments:

Re: [MW:34913] Filler wire

E71T-1C  is Charpy Impact tested at -20degC E71T-1CJ is Charpy impact tested at -40degC. AWS Classification for FCAW is only a supplementary...