During the holiday, how should idle screw air compressors be managed？ 

As the workshop’s core air supply equipment, the screw air compressor cannot simply be shut down and left unattended during holidays without risk. Improper shutdown management can easily lead to equipment corrosion, water accumulation in pipelines, and component damage; upon resuming production after the break, issues such as start‑up failures and unstable air supply may arise, delaying the production schedule.

Before the holiday shutdown, conduct a comprehensive inspection and standardize the shutdown process.

Pre‑shutdown preparation is critical; it is recommended to complete a full‑process inspection one day before the shutdown to prevent equipment from being taken offline while still faulty. 

1-Normal shutdown procedure:

deactivate the compressor’s load/unload button and allow the unit to run at no load for 10–15 minutes to purge internal compressed air. Once the equipment temperature has dropped below 40°C, then switch off the main power supply. Direct emergency shutdowns are strictly prohibited.  

2-Oil‑gas system check:

Verify the compressor’s lubricating oil level, ensuring it is at the midpoint of the oil sight glass. Any cloudy or expired oil must be replaced in advance. Close the oil‑gas separator drain valve to remove internal condensate and prevent oil sludge buildup.  3-Piping and dryer inspection: Sequentially close the compressor outlet valve and the receiver tank drain valve, then open the drain valves at the ends of the compressed air lines to expel any residual water, thereby preventing low‑temperature corrosion during the shutdown period. Disconnect power to both refrigerant dryers and desiccant dryers, and drain any accumulated water from inside the dryers.  

4-External environment cleanup: Remove debris and dust from around the compressor, maintaining adequate ventilation and keeping the equipment dry. Close the doors and windows of the equipment room to prevent rainwater and dust from entering. Also, disconnect power to all auxiliary components to eliminate potential leakage hazards.

Resumption of work: conduct item-by-item inspections and ensure a smooth startup.

1-Pre-Startup Recheck:

Verify the lubricating oil level and the status of all valves, ensuring that all drain valves are fully closed. Remove dust from the equipment, inspect electrical components and belt tension, and confirm that nothing is loose or damaged before preparing to start.

2-No Load Test Run:

First, energize the equipment and run it at no load for 5–10 minutes, observing for any unusual noises or vibrations and checking that the pressure and temperature gauge readings are within normal ranges. Only proceed to loaded operation if no abnormalities are detected.

3-Air Consumption System Inspection:

Open the air supply valves, check the piping for leaks, and test the performance of the refrigerant dryer and air receiver tank, ensuring that the compressed air pressure and dew point meet production requirements before putting the system into regular service.