Cool Gel to minimize distortion ?

[capntom62]

In the Aerospace industry some of our Mfg. Engineers talk about using "cool gel" type of products to minimize distortion during welding. Has anybody used it and had success with it ? I have only used copper bars on flat surfaces as heat sinks.

 

[kingnero]

I've used everything from water, dry ice, to blowers to cool down steel parts during welding, but I am not aware of this "cool gel".
A quick google showed a demonstration video. I can't say I'm convinced...

 

[Guest102023]

Sounds like a gimmick

"If you don't have time to do the job right the first time, when are you going to find time to repair it?"

 

[TugboatEng]

It makes sense if you're welding near areas that may be damaged by heat such as a glued joint.

As for controlling distortion, I think of it as two types. There is distortion due to heat and distortion due to cooling.

Distortion due to heat is caused by the localized heating of the structure. It normally returns to it's original shape once it cools. If the distortion is large it can create stress on the structure which causes plastic deformation or cracking. In this case you'll want to preheat the structure.

Distortion during cooling happens as the weld solidifies. This occured within the HAZ and cannot be minimized with additional heat sinking or cooling.

Faster cooling has some benefits for alloys such as stainless steel.

 

[DAVIDSTECKER]

You might look into Meta-lax or some other vibratory stress relieving system.
I understand it can be applied while welding to reduce distortion.

 

[Guest102023]

Vibratory stress relief is most assuredly an overhyped gimmick, in the same category as recrushed slag and T.I.M.E. gas.

It can be made to work only on relatively simple configurations, each of which requires some prior development work. The problem of how to measure the effects on production pieces will always remain.


"If you don't have time to do the job right the first time, when are you going to find time to repair it?"

 

[weldstan]

Over 20 yers ago, I contacted over a dozen welding engineers/metallurgists of differnet companies including NASA who have used the process. While a number of them didn't find any effective stress relief. Among those who did find positive effects, the great majority only found it effective when applied during welding. Only one of them actually compared stress with both as welded and vibratory stress relief applied during using sensors and it clearly showed a stress reduction. As the NASA engineer said to me, "I don't know how it works but it's another tool to have in the toolbox." Based on my paper on the above, my company did purchase a system for a perticular project and used it to no detrimental effect but I cannot say that is was effective either.

 

[david339933]

I use Meta-lax on one particular repeat vessel. While I was skeptical to say the least, it actually reduced distortion in this particular application (2 - P5A plates sandwiched together with multiple stays) As weldstan states, it is only effective if done while welding. I can't seem to find another use for it though.....so it sits idle for 11 - 23 months at a time.

 

[Guest102023]

Applying the technique while welding would be a very impressive party trick.

"If you don't have time to do the job right the first time, when are you going to find time to repair it?"

 

[david339933]

Not impressive at all....considering it is designed to do that.