TIG Welding queries

By teamunwired Date 06-25-2009 14:36

Hello!
We students here at NIT Calicut,India are competing for a vehicle design & fabrication contest- Baja SAE Asia 2010. We have chosen 4130 Chromoly Alloy Steel tubings/pipes as the material for our Roll Cage(Chassis). The following are the specs:

Tubing Material: 4130 Chromoly Alloy Steel
Outer Dia(OD)= 1.25 inch
Wall Thickness= 0.065 inch (1.65 mm)

The roll cage has to survive the harshest of punishment of a 4 hour endurance race on an off-road track. I would really appreciate if answer the following queries:
1. Does TIG Welding have a clear advantage over MIG and Arc Welding in our case? If so, what are the advantages?
2. Does TIG Welding require stress relieving/ heat treatment?

Thanking you in anticipation

Kind Regards
Prateek Kalyankar
NIT Calicut,India

By jstasney (*)

Date 07-03-2009 15:04

Good technique with TIG is clearly superior.
Yes, post weld heat treatment stress relieving would be advisable.

By sled_king (*)

Date 10-04-2009 14:18 Edited 10-04-2009 14:21

Tig is superior for welding root passes on pipe and in your case tube.
Is is very controllable and so much cleaner.
Tig is the method of choice at my work for welding root passes on high pressure boiler pipe.
In my opinion, no stress relieving/heat treatment is required for what you want to do (weld in a roll cage) with the material your using.
The disadvantages of tig are; low deposition rate and the cost.