Work Lead Connection (Grounding) for Weld Positioners

May 17, 2017

Weld Positioning Products

Without a properly attached and functioning Work Lead connection, the current can travel through the operator and/or weld positioning equipment, causing damage and/or injury. An improperly connected Work Lead may also negatively effect the weld quality.
 

Work Lead Connection – Not the Weld Ground Connection

Workpiece to weld positioner to welding power source sketch-IRCO Automation
The return path for the weld current is often incorrectly called the ground connection. This becomes even more confusing when you consider that most welding positioner manufacturers, including IRCO, still use terms like Brush Ground, Rotary Ground, etc.
 
This article will only be focusing on Work Lead connections and how it relates to welding positioners. For information on Weld Grounding, please refer to the appropriate safety standards.


 

Rotating Parts – Work Lead Considerations

For most welding applications, the welding current is returned from the workpiece to the power source using a clamp and cable with a sufficient current capacity rating. When dealing with rotating parts, like pipe or tanks, this can lead to additional challenges. If a standard clamp (and cable) is connected to a rotating cylinder the cable can begin to “wind”, possibly causing damage and eventually failure. To solve this issue fabricators will use a rotating connector, like a clamp, to prevent the cable from being wound while the workpiece turns.
 
Pre-Grinding-Tank Welding System with Self Aligning Turning Rolls-IRCO Automation

Connecting the Work Lead to an IRCO Welding Positioners

Unless specified, IRCO Rotating Positioners (Head & Tail Stocks / Tilt Rotate Weld Positioners / Pipe Rotators) will come with an engineered mechanism that provides a path for the welding current to travel back to the power supply. These will sometimes include additional components (e.g. Brush or Rotary Grounds) and will always have a specific nub/protrusion/clamp to attach the Work Lead cable. This functionality eliminates the need to attach directly to the workpiece and can: reduce wear & tear on the cable and decrease set-up time by eliminating the unclamping/clamping of the ground cable on each workpiece.

1.5K PTR-Tilt Rotate Welding Positioner_Highlighted Work Lead Connection_s-IRCO Automation
6K Welding Head+Tail Stocks_s-IRCO Automation



 

General Considerations for Connecting a Work Lead on a Positioner

  • Always ensure that your weld current return path is rated for your welding application.
  • Not all welding positioners are rated to carry the same levels of current. Just because a machine includes an engineered Work Lead mechanism doesn’t mean that the machine is rated to carry sufficient amperage for the welding application.
  • Never use cables, clamps/connectors that have visible signs of wear or abuse.
  • If the Work Lead does not have a solid/clean connection; it should be replaced and/or repaired by a certified electrician.
  • A scheduled maintenance program performed by a qualified and trained technician will almost always pay for itself in the end.

 

Get the Right Equipment for the Application

When purchasing a new welding positioner IRCO can help assess if the included ground capacity is suitable for your application. For higher amperage processes, the grounding capacity can be upgraded to help ensure safe use of the equipment. If you would like more information, or have any other questions, contact an IRCO representative.
 

References:
American Welding Society, ANSI Z49.1:2012 “Safety in Welding, Cutting, and Allied Processes