Your guide to correcting the most common resistance welding issues
Resistance welding can be a challenging process to master, and even experienced welders run into issues from time to time. Nothing can be more frustrating than an inconsistent or faulty weld, which can cause costly production downtime. Knowing the root cause and how to fix it can be even more difficult. That’s where the “Resistance Welding Troubleshooting Guide” comes in. This guide is a comprehensive resource that will help you diagnose and solve issues you may be having with projection or spot welding. It covers everything from common conditions you might encounter to possible causes and the corrective actions you should take to improve your welding. Whether you’re a seasoned pro or a novice in the field, this guide is an essential tool to have in your arsenal.
PROJECTION & SPOT WELDS | |||
Screen | Condition/Diagnosis | Possible Causes | Corrective Action |
Thickness | Exceeds (HL) | Fit-up problem | identify and correct |
Electrodes damaged | Dress or replace as needed | ||
Exceeds (LL) | Workpiece damaged or missing | Identify and correct | |
Electrodes worn | Replace electrodes and/or rezero linear transducer | ||
Force | Exceeds HL | Force is too high | Check head for binding; decrease pressure |
Exceeds LL | Force is too low | Check head for binding; increase pressure | |
Varies widely | Friction in head | Clean/repair/lubricate as required | |
Current | Exceeds HL | Problem with machine connections or control regulation | Check machine connections/tune control settings/widen limits as required |
Exceeds LL | |||
Voltage | Exceeds HL | Current set too high | Decrease Current setting |
Force is too low | Check head for binding; increase pressure | ||
Secondary resistance high | Clean connections; replace cables, tips | ||
Exceeds LL | Current set too low | Increase Current setting | |
Force is too high | Check head for binding; decrease pressure | ||
Conductance | Exceeds HL | Force is too high | Check head for binding; decrease pressure |
Secondary shorted | Check connections, cables, shunts, etc. | ||
Exceeds LL | Fit-up problem | Identify and correct | |
Force is too low | Check head for binding; increase pressure | ||
Secondary resistance high | Clean connections; replace cables, tips | ||
Power | Exceeds HL | Current set too high | Decrease Current setting |
Force is too low | Check head for binding; increase pressure | ||
Exceeds LL | Current set too low | Increase Current setting | |
Force is too high | Check head for binding; decrease pressure |
PROJECTION WELDS | DISPLACEMENT | SPOT WELDS | ||
Condition/Diagnosis | Possible Causes | Corrective Action | Possible Causes | Condition/Diagnosis |
Expulsion Weld is too hot | Force is too low | Check head for binding; increase pressure | Force is too low | Expulsion Weld is too hot |
Current set too high | Decrease Current setting | Current set too high | ||
Electrodes damaged | Dress or replace as needed | Electrodes damaged | ||
Exceeds LL Weld may still be acceptable | Several | Lower LL / Raise HL or take no action | Several | Exceeds LL Weld may still be acceptable |