Help needed- V Bend Test Plate

Date 04-04-2006 23:43

Hi all,
I am getting ready to begin making my V-Bend test plate, i will be doing a groove weld Butt Joint in the Flat Position, I will be putting my Root down with a 6010 and capping it off with a 7018, the question is after i bevel off my plates and im ready to join them together how should i place the plates towards one another, I at first thought they could just lay flat but Now ive been told they should be at somewhat of an angle? Does anyone have any online illustrations of how these should be set up? or maybe just a word of advice?

By pipewelder_1999 (****)

Date 04-05-2006 03:18

You can preset the plates to allow the distortion that results from welding to pull the plates into position as opposed to causing them to be distorted out of position. See http://www.weldinginspectionsvcs.com/misc/preset.htm

Bead placement, heat input, and restraint can all affect the amount the plates distort but presetting them is a method that works fine. I have bent a few of them with varying amounts of distortion and haven't noticed much difference in the results. Plain carbon steel is pretty forgiving as long as the weld is solid.

Here are some other things that may be of interest.

http://www.weldinginspectionsvcs.com/beadSequence.htm

http://www.weldinginspectionsvcs.com/WeldCapProfile.htm

http://www.weldinginspectionsvcs.com/halfInchJointFitup.htm

Have a nice day

Gerald

By welder5354 (**)

Date 04-05-2006 12:48

What size plate are you using? The thicker the plate, the more distortion.

By thcqci

Date 04-05-2006 23:28

The heavier plates will tend to try to distort more. But simple observing your heat input and interpass temperatures will cure most of the problems. I have seen welders want to use strong backs and/or run long "tacks" on a backing bar to try to reduce distortion. But giving the welder the WPS and making sure he understands it goes along way toward getting controlled heat input.

When I started here, the welders had never had a "tester" monitor their interpass temps before. For that matter, they never had a "tester" monitor their volts, amps, gas flow or even give them a WPS. They thought I was nuts! They said they would just give them some coupons and tell them to weld them up. Needless to say they know better now.