ROLLER 2533781 - Caterpillar

Post Weld Treatment - TIG Dressing
The fatigue performance of fabricated structures involving fillet welded attachments to highly stressed members is, among other things, controlled by the profile or geometry of the weld toe. Fatigue performance improvements can be achieved through alteration of the original, as-welded toe profile by several post weld treatment options. This procedure describes a method whereby an electric arc is used to reduce and/or remove unfavorable profiles/stress risers thus creating a smooth, seamless transition from one component to the next component.Note: Training: Anyone performing this procedure is advised to view the training video “Post Weld Treatment: TIG Dressing Fundamentals”.Caterpillar Channel 1 Videos
To provide clarification and details, a video has been created outlining the Post Weld - TIG Dressing. Reviewing the video prior to performing any Post Weld - TIG Dressing.Note: A CWS login is required to access Caterpillar Channel 1.
Illustration 16 g06285354https://channel1.mediaspace.kaltura.com/media/Off-Highway+Truck+Post+Weld+Treatment+-+TIG+Dressing/1_gmocv9ae
The link above contains the following video:
Post Weld - TIG DressingEquipment Requirements
Table 9
Required Equipment
Tool Description
GTAW (TIG) Power supply and a torch. The power supply must be able to produce 200 amps (min. 60% duty cycle) with a hand control or a foot control.
Polarity - DC negative
Shielding Gas 100% Argon and flow meter
Electrode Lanthanated or
Ceriated or
Thoriated Tungsten
2.4 mm (0.09 inch diameter)
If needed:
ER70S-2 filler metal
1.5 mm (0.06 inch diameter)
Grinder Pneumatic or electric with carbon steel wire wheel attachment
Grinding Wheel Aluminum Oxide
Radius gauges Method
The first steps to ensure that proper TIG dressing are cleanliness and tungsten electrode preparation.The fillet weld and surrounding base metal must have all contaminants thoroughly removed. It is imperative that all paint, rust, dirt, oil scale, and silicate islands are non-existent, remove by using a grinder with a carbon steel wire attachment.
Illustration 17 g03363246
2.4 mm (0.09 inch) Tungsten Electrode Preparation
(A) Grinding Marks
(B) 2 X 3 diameter
(C) 1/4 diameter
Prepare a 2.4 mm (0.09 inch) tungsten electrode. Refer to the dimensions that are shown in Illustration 17. The grinding marks should run parallel to each other.
Adjust the shielding gas flow rate to 15 - 25 CFH. Adjust the current control to approximately 200 amps. If a ramp down control is present on the power source, utilize the ramp down control to ensure that proper crater fill control is achieved.
Several different techniques exist for TIG dressing due to the variation of the contour of the fillet weld toe. The contour of the fillet weld toe must be reshaped. Use a stringer or weave manipulation of the torch to achieve a smooth radius of the weld. A minimum radius of 5.0 mm (0.20 inch) must exist between the base material and the weld metal.
Illustration 18 g03363256
Stringer Technique
(D) 0 degree work angleNote: Use a 10 degree to 15 degree push angle for the stringer technique.
Illustration 18 represents the stringer technique of welding. The center of the arc needs to be 0.0 - 2.0 mm (0.0 - 0.08 inch) from the weld toe into the base material.
Illustration 19 g03363260
Weave Technique
(E) 0 degree to 45 degree work angleNote: Use a 10 degree to 15 degree push angle for