Air Compressor Inlet Valve
By Published On: January 2, 2024Views: 154

How to deal with air compressor inlet valve injection?

The intake valve plays a crucial role in intake control, loading, unloading, capacity control, and preventing oil injection. It operates based on power loading and unloading, usually featuring rotating disc or reciprocating valve plate mechanisms.

Common Causes of Oil Injection into the Air Compressor Intake Valve:

  • Poor oil and gas separator
  • Blocked oil return check valve
  • Ineffective air filter filtration
  • Adhesion of impurities to the inlet valve spool sealing surface
  • Wear in the intake valve piston and spring seat matching pair

Oil Injection Scenarios:

  • Oil injection often occurs when the compressor suddenly stops, causing the air intake check valve to close late, resulting in outward oil spray.
  • To address this, remove lubricating oil, adjust discharge to zero, and test for ongoing oil spray from the intake valve.

Dealing with Air Compressor Intake Valve Oil Injection:

  1. If oil injection persists, the intake valve is likely leaking. Solutions include repairing or replacing the spool or replacing the spool check diaphragm.
  2. If oil injection ceases, conduct tests to identify the fault point. This may involve checking the check valve, removing impurities, and assembling it back for testing. If faults persist, consider additional tests.

Handling Intake Valve No Longer Spraying Oil:

  1. Remove the check valve, clean impurities, and test. If the fault persists, assemble a ball valve between the oil drum and the intake valve and test again.
  2. Observe oil spray during compressor shutdown. If observed, increase the oil baffle between the intake valve seat and the host. If no oil ejection occurs, the oil distribution system may be faulty.

Determining Oil Distribution System Issues:

Connect the pipeline between the oil drum

kotech Control Valve

Control Valve(High Pressure Capability – Quiet Operating Relief Valve)

and the intake valve, reduce the oil level, and test. If oil injection decreases, it indicates an unreasonable oil drum design. If not, check and replace the oil content.


Addressing air compressor inlet valve injection involves understanding and resolving issues related to leaks, check valve problems, and oil distribution system failures. Regular maintenance and prompt troubleshooting are essential for optimal compressor performance.

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