The Advantages and Disadvantages
In the modern day many welders prefer to walk the cup over freehand as it saves them burning their hands, provides better control and a more consistent finish to the weld when the technique has been mastered, but with most things walking the cup has its advantages and disadvantages.
Walking the Cup
- Better control of the arc manipulation and arc length
- More consistent electrode angle during hot pass, filling, and capping
- Increased consistency with travel speed
- Improved weld uniformity with weld width, shape and profile
- Walking the cup is limited to access of the weld joint, when welding in-situ, in tight situations with limited access the technique cannot be used.
- The technique is often used for the root runs in pipe and overhead butts, this produces an incorrect electrode angle and especially for positional welding it can lead to a concaved root run or incomplete fill on the bottom section of pipe or any overhead welding as the arc force is not focused where you need it to support the molten weld pool.
- Voltage fluctuations as the electrodes distance from the weld pool fluctuates during the rotation of the cup and the forward movement.
- Higher heat inputs can result from welders focusing more on the appearance of the weld as opposed to travel speed.
- Arc Strikes can happen easily if the ceramic cup slips during welding, usually resulting in a larger and longer arc strike, this often happens when welders are in awkward positions or still learning to master the technique.
- The repetitive motion and rolling of the wrist may lead to RSI injury and long-term movement issues later in life.
- It increases wear on the GTAW torch and flexible neck.
- Need High frequency start
- Can use any equipment, fixed head torches, scratch start
- More constant arc length and therefore arc intensity
- Good for welding in all positions and restricted access
- Better control of the welding torch, less likely to produce arc strikes.
- Heat inputs are typically lower due to the ability to move forward faster whilst maintaining control, this also allows for higher amperage setting to be used for increased production and travel speeds.
- Better weld pool manipulation as more appropriate electrode angles can be used whilst applying the root run in positional welding situations.
- Less consistency with electrode angle, this can lead to suck back of the root in the overhead position and push through in the flat position
- Less control on weld width, shape and profile
- Less control with weld uniformity
- Takes longer to master
The best welders have the ability to use both techniques and are able to apply the two different techniques to match the given situation, this gives these welders a much better set of skills and greatly improves their employability over the welders that can only walk the cup.
For people who are learning how to weld using the GTAW process, the best advise is to learn free hand first, master this using both left and right hands and then learn how to walk the cup.
When we train people how to TIG weld, or any welding process for that matter focusing on getting the fundamental principles right provides a sound foundation for the development of the necessary skills later on.
What can Technoweld do for you?
Technoweld provide a full range of welding services from Inspection and Supervision to Tailored Training to suit your business requirements. If you would like to upskill your TIG welders, Technoweld can assist you, contact us on 1300 00 WELD.