Defective Air or Hydraulic System


A faulty air or hydraulic system is one which adversely affects the electrode motion, follow-up, or force application.


Defective systems can result in excessively fast or slow resistance welding electrode movement. A fast system may result in electrode bounce, electrode/workpiece damage, etc. A slow system may result in surface expulsion if current initiation occurs before adequate weld force is established. Also cycle time may be increased.

Defective systems may also result in poor electrode follow-up.


The condition may be indicated by:


Quality, Workplace Issues, Cost, Downtime, Maintenance, Throughput (cycle time; PPH), are all potentially affected by this condition.

Subordinate Causes

  • Dirty filter(s)
  • Broken, worn, kinked hoses and/or seals
  • Loose or broken fittings
  • Low/no oil in hybrid system reservoir
  • Hydraulic pump malfunction
  • Air compressor malfunction
  • Incorrect valve setting
  • Valves not operating properly
  • Contaminants in system
  • Wrong hydraulic fluid