2901030200 Atlas Copco air compressor KIT INLET VALVE GA90VSD Original

I. Core Function of Atlas Copco Air Compressor Intake Valve

Intake regulation: Automatically opens or closes the intake channel according to the pressure changes in the storage tank or the system pipeline network, controlling the amount of air entering the main unit (such as opening when the pressure is lower than the set value and closing when it is higher than the set value).

Load / Unload Switching:

Load: The intake valve is fully open, allowing air to enter the main unit for compression, and the air compressor is in operation.

Unload: The intake valve is closed (or partially closed), the main unit has no air intake, and it enters a no-load state (reducing energy consumption).

Protective Function: Some intake valves integrate a backflow prevention function to prevent compressed air from flowing back to the main unit and avoiding reverse impact during shutdown.

II. Common Types and Working Principles of Atlas Copco Air Compressor Intake Valves

Based on the type of air compressor (rotary vane, piston) and control method, intake valves are mainly divided into the following categories:

1. Intake Valve for Rotary Vane Air Compressors

Diaphragm valve type intake valve (most common)

Structure: Composed of a valve seat, diaphragm (cylindrical valve core), and cylinder / electromagnetic valve drive mechanism. The opening degree is controlled by the rotation of the diaphragm (0 - 90°).

Principle: When the system pressure is lower than the set value (such as 0.6 MPa), the electromagnetic valve is energized, the cylinder pushes the diaphragm open, and the intake volume increases as the opening degree increases; when the pressure reaches the upper limit (such as 0.8 MPa), the diaphragm closes, achieving unloading.

Features: Simple structure, fast response, suitable for small-sized rotary vane machines (such as a flow rate of ≤ 50 m³/min).

Sliding valve type intake valve

Structure: The intake port area is adjusted by the axial movement of the valve core (slide block).

Principle: Combined with a pressure sensor and servo mechanism, it can achieve continuous adjustment of the intake volume (the intake volume changes continuously), rather than only full open / full close, and is more energy-efficient.

Features: High adjustment accuracy, suitable for large-sized rotary vane machines or variable operating conditions (such as scenarios with large flow fluctuations).

Combined intake valve

Integrates diaphragm valve, backflow valve, and unload exhaust hole (removes residual air in the main unit during unloading to reduce idle load), such as the "intake valve + minimum pressure valve" combination commonly used in Atlas Copco GA series.

2. Intake Valve for Atlas Copco Air Compressor Piston-type Air Compressors

Spring plate valve / one-way valve

Structure: Composed of valve plate (thin metal plate or rubber plate) and valve seat, automatically opens / closes based on the pressure difference in the cylinder.

Principle: When the piston descends, a negative pressure is formed in the cylinder, the valve plate is pushed open, and air enters; when the piston compresses, the pressure in the cylinder increases, the valve plate is pressed closed to prevent gas backflow.

Features: No external drive mechanism, operates automatically by mechanical force, suitable for small-sized piston machines (such as household or portable air compressors).

III. Key Parameters and Selection of Atlas Copco Air Compressor Intake Valves

Nominal diameter: Matches the inlet size of the air compressor (such as DN50, DN80), ensuring that the intake volume meets the requirements of the main unit (too small a diameter will result in insufficient suction and affect the exhaust volume).

Working pressure range: Needs to cover the rated pressure of the air compressor (such as 0.7 - 1.0 MPa), ensuring reliable sealing under high pressure.

Control method:

Pneumatic control: Driven by compressed air (fast response, suitable for industrial scenarios).

Electric control: Directly driven by the electromagnetic valve (simple structure, suitable for small equipment).

Response time: The time from receiving the signal to completing the action (usually ≤ 1 second), avoiding excessive pressure fluctuations.

IV. Common Faults and Maintenance Points of Atlas Copco Air Compressor Intake Valves

Common faults and causes Intake valve sticking: Impurities (dust, oil residue) accumulate between the valve core and valve seat, or insufficient lubrication causes the valve core to wear and fail to fully open/close (manifested as inability to reach the required pressure during loading and inability to release pressure during unloading).

Poor sealing: Valve plates / butterfly plates wear, and sealing rings age, resulting in air leakage during unloading (increased energy consumption during idle operation of the main unit, or even inability to unload).

Failure of drive mechanism: Cylinder leakage, electromagnetic valve jamming (for pneumatic control type), or motor burnout (for electric control type), causing the intake valve to fail to operate.

Maintenance suggestions

Regular cleaning: Disassemble the intake valve every 2000 to 4000 hours, clean the valve core and valve seat with kerosene or special cleaning agent, removing oil residue and impurities (especially for screw-type intake valves, which are prone to clogging due to the mixture of oil and gas).

Check sealing components: Replace aged O-rings and valve plates (such as piston-type spring valve; if the valve plate has cracks or deformation, it should be replaced immediately).

Lubricate drive components: Apply special lubricating grease to moving parts such as cylinder piston rods and rotating shafts (such as silicone-based lubricating grease; avoid reaction with oil and gas in compressed air).

Calibrate control pressure: Adjust the pressure switch or PLC parameters to ensure the intake valve operates precisely at the set pressure point (such as 0.6 to 0.8 MPa).