Too many organizations weld of machinery causing electrical and mechanical failures. This Tool Box Talks explains the "how to" in a way anyway can understand and make it happen. All I ask is your feedback to this document. I have many other Tool Boxes, download them at www.maintenancephoenix.com.

1. WELDING ON EQUIPMENT
“TOOL BOX TRAINING”
Maintenance Supervisors should use this tool to train their maintenance techs, welders and
contractors - 10-20 minutes – Post them in the Maintenance Shop after use
Electric Arc caused by welding on equipment is one of the Failure Modes for Rolling Element and Non
Rolling Bearings. Electric Arcing can also cause electrical component failure in MCCs and Electric
Motors and Drives.
So why do we accept this failure mode when it can be eliminated?
General Rules which must be followed by maintenance personnel and contractors:
(Caution: follow these recommendations only if you want to stop self induced failures caused by welding)
1. Ground leads and welding leads must be the same length on all welding machines by maintenance and
contractors. (correct immediately)
2. Grounding of welded surface must be within 6” of welded surface or a Reliability Engineer must approve the
variation to the process. (Post this notice on welding machines)
3. All contractors must follow this policy. (insure policy is followed by all)
Failure Modes experienced from Maintenance Welding
- Electric Arcing caused by Welding on equipment
- Flaking caused by Electric Arcing (secondary failure mode)
WARNING: Ensure your contractors follow the same process to eliminate electric arcing.
Warning: failure to accomplish this one task properly will cause bearing failure by “electric arcing”
which is a failure mode of bearings. In addition it will cause failure of many different electrical
components. Remember: Electric current from welding will always follow the path of least Resistance.
Remember Welders are not reliability experts but professionals who know how to weld to construct and repair
using all types of welding processes. I was a certified welder for many early years and later became a reliability
specialist and conducted Root Cause Analysis on many failures around the world and have seen this problem in
almost every plant and site I have visited. Stop this on your site now.
If you have questions or comments please send them to me at rsmith@gpallied.com
Page 1 of 1 GPAllied
4360 Corporate Road
“When commissioning any new existing pump use Vibration Analysis to Suite 110
ensure there are no identifiable defect on the pump or motor” Charleston, SC 29405
www.gpallied.com Office (843) 414-5760
Fax (843) 414-5779
Copyright 2010