Turn off the air compressor or dryer first
In compressed air systems, the correct shutdown sequence should follow the following principles to ensure equipment safety and system life:
recommend shutdown sequence:
- close the air compressor first
- reason: The air compressor is an air source. After the system pressure is stopped, the system pressure will gradually decrease to avoid the “idling” of the dryer when there is no compressed air, causing the desiccant to fail or the equipment to be damaged.
- Operation press the shutdown button of the air compressor and wait for the unit to stop naturally (to avoid frequent start-stop and damage to the motor).
- Wait for system pressure to drop to safe value
- role: Prevent the sudden release of high-pressure gas when the dryer is stopped and impact the pipeline or valve.
- Standard: It is usually necessary to reduce to normal pressure (0 MPa) or keep a slight positive pressure (such as 0.1-0.2 MPa) according to equipment requirements.
- Turn the dryer off again
- key Points:
-
adsorption dryer: Stop the machine after completing the regeneration cycle (to avoid residual moisture damage to the desiccant).
-
Freeze dryer: Just close it directly, but it is recommended to wait for the condensate to drain before powering off.
-
- key Points:
Exceptions and considerations:
-
system with aftercooler: If the dryer is integrated with an aftercooler, turn off the cooling water/fan first, and then stop the dryer.
-
linkage control system: Some intelligent systems will automatically stop according to the preset sequence, and the equipment manual must be followed.
-
Long-term shutdown: It is recommended to manually drain the water before closing the dryer to prevent the condensate from corroding the pipeline.
Start-up sequence (additional knowledge):
-
start the dryer first.: Ensure that the compressed air is dried before flowing to the downstream equipment.
-
Open the air compressor again: Avoid undried air entering the system to contaminate the pipeline.
Summary:
follow” stop the air compressor first → stop the dryer again“The order can maximize the protection of equipment, extend the life of the desiccant, and prevent pressure shock. The specific operation needs to be combined with the equipment type (e. g. adsorption/refrigeration) and the manufacturer’s recommendations.
