Distortions in welded structures

Date 06-10-2003 13:21

Purchase a copy of Lincoln's "The Procedure Handbook of Arc Welding".
There is a section on weld distortion and control methods.
If you call Lincoln at 1-216-383-2211, you can order it directly, and I believe the cost is $15 or $20 (which is a good deal for a 8"x10.5" book, 2" thick)

Chet Guilford

By jwright650 (*****)

Date 06-10-2003 13:41

S.K.JOSHI,
If you will notice that when these frames or what ever are welded up they all don't distort exactly the same. Most welders with experience will get a feel for how much distortion will result and compensate for this by welding and applying heat opposite thier welds to straighten. Alternating stitch welds and such will help but not totally. The book that CHG has recommended is a good source of info on how to help with distortion. Balancing the heat is key and that book shows in detail how this can be done as well as other methods of dealing with distortion(fixtures, jigs, etc....).
John Wright

By Niekie3 (***)

Date 06-10-2003 17:49

Hi S.K.Joshi

There are many different models and equations around for predicting distortion, and they all work. The problem is however that one works under a given set of circumstances, and another works under a slightly different set of circumstances. It is mostly difficult to know which one to use for your particular situation. If you have a very simple configuration, you can usually deduce which equation to use, to give a good result. When your geometry becomes more complicated, then the fun and games start!

The bottom line is that as we sit at the moment, there are no "analytical" models that are good under all circumstances. The closest that people have come to this ideal is by building FEA models. This is however usually of little use to the average man on the street. (or is that behind the arc?)

This is a problem that I am presently working on, in some research that I am doing. If I get some really good answers I will let you guys know, but don't expect something in the short term!

Regards
Niekie Jooste
Fabristruct Solutions