TIG

TIG Technique
GTAW (Gas Tungsten Arc Welding) and TIG (Tungsten Inert Gas) welders require proper techniques. The position of the TIG / GTAW welding torch, angle of filler rode, speed of welding torch and the feed of electrode are important welding parameters for a good TIG joints.

TIG Resources

TIG or GTAW Welding Technique

Tungsten Inert Gas (TIG) / Gas Tungsten Arc Welding (GTAW) Technique

TIG or GTAW is the most difficult to master an arc welding technique. This is because the operator/welder needs two hands to produce the weld (unless autogenous welding is used)

To start (lift-arc start method) the TIG welder touches electrode to the workpiece. The electrical energy and the shielding gas are now triggered with the hand control. At this stage the welder electrode should be held to workpiece for 1-2 seconds. Then it is slowly lifted and arc is produced.

The TIG or GTAW welding machine process is designed to avoid overheating, sticking and getting contaminated. This is due to the output contactor, which does not energise untill the electrode touches the workpiece. There is another TIG start up method: HF Start. It uses high frequency turns to help start the arc.

TIG / GTAW Welding Torch Position

After arc is struck, the welder moves nonconsumable Gas Tungsten Arc Welding (GTAW) electrode in small circular motion. Then he tilts TIG electrode 75 degrees to the workpiece at the start of the weld puddle. Welder produces weld by mowing the tungsten electrode in the direction of weld. The consumable filler rod is now approached at 15 degrees to the weld (for non-autogenous TIG welding process).

The filler rod is now removed and the rod is placed to the front of the weld pool. From there the TIG welding process is repeated. The autogenous TIG or GTAW welding does not require a filler rod. Therefore, it requires only three stages.

TIG / GTAW Welding Procedure

1. Form pool with rotational movement
   
   
   
2. Tilt TIG torch 75 degrees and move to the start of puddle
   
   
   
3. Slowly add filler rod at 15 degrees
   
   
   
4. Slowly remove filler rod at 15 degrees
   
   
   
5. Move TIG torch to the front of the pool
   
   

For autogenous GTAW welding step 3 and 4 is omitted.

Tungsten Inert Gas (TIG) / Gas Tungsten Arc Welding (GTAW) Joints

TIG welders produce the joints if short arc is applied.
Uniform travel speed and the constant feed of electrode provides the best results.

TIG / GTAW Butt Joint

For butt joint the welder should hold filler rode at about 15-20 degrees to the weld.

The torch itself is perpendicular to the normal (and 70-75 degrees to the weld).



TIG / GTAW T Joint

For T joint, the TIG / GTAW welder's torch is 20 degrees to the vertical plate.

The rod is 10 degrees to the vertical plate and 20 degrees to the weld.



TIG / GTAW Lap Joint

The lap joint uses different TIG technique. Torch is 40 degrees to the edge of the top plate.

The filler rode is 30 degrees to the top plate. Corner Joint is the most demanding. However, TIG welders use the same technique as in the case of butt joint.