Which Items Are Mandatory for Daily Inspection of Air Compressors?

Mandatory Inspection Items Before Startup (3 Items)

1. Lubricating Oil Level and Quality

   Check the oil gauge to ensure the oil level is between the “MAX” and “MIN” marks. If insufficient, replenish with the same type of special lubricating oil. Observe the oil quality; if the oil turns black, emulsifies, contains impurities, or has an unusual odor, shut down the machine immediately for oil replacement to avoid component wear due to insufficient lubrication.

2. Condensate Drainage
   Open the drain valves of the air receiver, oil-gas separator, and filters to completely drain internal condensate. Especially in humid environments or after long-term shutdown, accumulated water will accelerate internal corrosion and contaminate compressed air.
3. Electrical and Instrument Status
   Inspect power cords and terminals for looseness, overheating, or burn marks. Confirm that the pressure gauge pointer returns to zero and the safety valve is free from rust and jamming. Ensure the emergency stop button is reset and there are no fault alarm codes on the control panel.

Mandatory Inspection Items During Operation (5 Items, Patrolled Every 1–2 Hours)

1. Operating Parameter Monitoring
   Closely monitor the discharge pressure (which must be stable within the rated range, e.g., 0.7–1.0 MPa) and discharge temperature (typically ≤ 95℃ for screw compressors and ≤ 100℃ for piston compressors). If the pressure fluctuates sharply or the temperature exceeds the limit, shut down the machine for troubleshooting immediately.
2. Abnormal Noise and Vibration
   Listen to the equipment operation sound; it should normally be a steady mechanical hum, without metal knocking, sharp whistling, or air leakage sounds. Observe the machine vibration amplitude; abnormal vibration is mostly caused by belt slippage, coupling misalignment, or bearing wear.
3. Leakage Inspection
   Focus on checking pipeline joints, cylinder heads, oil-gas separators, valves, and other parts for air or oil leakage. Tighten components for minor leaks and shut down the machine immediately for severe leaks.
4. Heat Dissipation System Status
   • For air-cooled models: Check if the cooling fan runs normally and the heat sink is free from dust blockage.
   • For water-cooled models: Check if the cooling water flow is stable, the water pipes are free from leakage, and the temperature difference between inlet and outlet water is normal (generally ≤ 5℃).
5. Load and Start-Stop Frequency
   Observe if the air compressor starts and stops frequently. Short-cycle frequent start-stops may indicate insufficient air receiver volume, pressure switch malfunction, or pipeline leakage, which requires timely troubleshooting.

Mandatory Inspection Items After Shutdown (2 Items)

1. Secondary Drainage
   After shutdown and pressure relief, open the drain valve again to completely drain condensate, ensuring no residual water is left in the tank to prevent pipeline cracking due to freezing at low temperatures at night.
2. Equipment Cleaning
   Wipe dust off the machine surface and remove dust accumulation on the motor and heat sink to maintain good ventilation and heat dissipation. Check if protective devices (such as belt guards) are intact.

Key Notes for Inspection

1. Safety Regulations: Before all inspection operations, shut down the machine, relieve pressure, cut off the power supply, and hang a “No Switching On” warning sign. It is strictly forbidden to perform operations on the cylinder head or air receiver under pressure.
2. Fault Handling: If abnormal parameters or fault signs are detected, shut down the machine immediately. Never operate the equipment with faults.
3. Record Keeping: Maintain an inspection log, recording the time of each inspection, the model of replaced parts, and operating parameters for future traceability and fault prediction.