Daily Maintenance — Care Procedures and Inspection Points for Solenoid Valves

Although compact and highly reliable, solenoid valves operating continuously in industrial environments require periodic maintenance to perform optimally. Scientific maintenance can significantly extend valve life and prevent unexpected failures that lead to production downtime.

Daily Inspection Items

1.Visual and Connection Checks

   Inspect the valve body for signs of damage, deformation, or corrosion.

  Check cable connections and terminals for looseness or oxidation.

  Observe for leaks during operation (use a soap solution on joints; no bubbles indicate a good seal).

2.Operational Responsiveness Check

There should be a clear audible "click" when the valve is energized and de-energized.

Sluggish or no response may indicate issues with the coil or spool.

Listen for abnormal sounds; a hissing sound may indicate internal seal failure.

3.Coil Temperature Check

Gently touch the coil housing with the back of your hand (observing safety precautions) to check for overheating.

Possible causes of abnormal heating: continuous full-load operation, over-voltage, or inadequate heat dissipation in high ambient temperatures.

4.Air Source Quality Check

Ensure the compressed air is clean and dry.

Check the condition of the upstream filter element and the water level in the filter bowl; drain as necessary.

Condensate must be managed promptly; use auto-drains and appropriate dryers if manual management is difficult.

Periodic Maintenance Schedule and Procedures

A tiered maintenance strategy is recommended based on the operating environment:

Note: Advance to the next maintenance level when cumulative operating hours reach 2000.

Valve Cleaning Procedure

Periodically disassemble the valve to remove internal oil, rust, or debris.

Use neutral cleaning agents (e.g., anhydrous ethanol) to avoid damaging metal parts and seals.

The spool can be cleaned using an ultrasonic cleaner (40kHz frequency, 3 minutes). Never use metal tools to scrape sealing surfaces.

Check inlet and exhaust ports monthly for blockages and purge them with clean, dry compressed air.

Seal and Wear Part Replacement

Seals (O-rings, gaskets): It is recommended to replace all seals during each major overhaul.

Springs: Replace immediately if cracks or defects affecting strength are found.

Replacement Intervals: For high-frequency applications, replace seals annually.

When installing new seals, apply a small amount of pneumatic-grade silicone grease (≤0.1g per part).

Coil Testing

Use a multimeter to measure coil resistance. Replace the coil if the deviation exceeds ±15% from the specified value.

Test insulation resistance; it should generally be greater than 500MΩ.

Check for signs of overheating, burnout, or poor armature attraction.