heat treating welded structures

[marmon]

At our shop we have 2 differential housings from large equipment, it is a typical rear end with lots of gusseting welded to it. My question is i would like to releive it some from all the welding. I do not have access to an oven to do it properly. One of the guys on the floor recomended using a tiger torch then cover it with welding blankets over night. My worry is that now the housing is straight. Will applying heat unevenly (torch vs oven) cause warpage, and will it even do enough to help any? What temperature should i shoot for?
thanks

 

[Metalguy]

If the housings are welded before final machining, they will probably warp during stress-relieving.

Can you take a scrap housing and experiment with it? If you're getting service failure because of fatigue cracks, SR can be a help. Also consider shot peening.

"I'm that dog who saw a rainbow, only none of the other dogs believed me." from "Kate and Leopold"

 

[marmon]

these are the first to be put in service. all welds were peened during welding process, but only from the slag removal. welding was done alternating sides constantly, and the overall temperature of the housing never went higher than 200 degrees F. Also the housing never pulled in any direction after welding. I am just hoping that no future problems arise from stress, as these were designed to replace already failing housings

 

[bklauba]

Another option is to vibratory stress relieve. What are the overall sizes, wall-thicknesses, and weights of the housings.

A website that should prove helpful:

http://www.airmatic.com/content/view/50/70/

BK