The worm gear wheel type impeller in Atlas Copco centrifugal air compressors. 1. Core Function
The impeller rotates at high speed (typically thousands to tens of thousands of revolutions per minute), using centrifugal force to accelerate and compress the air entering the impeller, converting mechanical energy into the kinetic energy and pressure energy of the gas, which is the key link for achieving air compression. In the multi-stage compression structure of centrifugal air compressors, the impeller needs to be combined with diffusers, bends, and other components to gradually increase the gas pressure to the target value.
2. High-aluminum impeller characteristics
Material advantages: Made of high-strength aluminum (such as aerospace-grade aluminum), it has the characteristics of low density and light weight, which can significantly reduce the inertial force and shaft load during the impeller's rotation, reduce energy loss, and is suitable for medium and low pressure, medium-speed working conditions.
Processing performance: Aluminum is easy to be processed into shape, and can realize complex blade surface designs (such as backward curved blades), optimize the airflow channel, reduce flow loss, and improve compression efficiency.
Application scenarios: Often used in medium and low-power centrifugal air compressors, or in scenarios where there are higher requirements for equipment lightweighting and energy consumption control.
3. Metal impeller characteristics
Material selection: Mostly use high-strength alloy steel (such as chromium-molybdenum steel, nickel-based alloys) or titanium alloys, with excellent high-temperature and high-pressure resistance, mechanical strength and fatigue resistance far higher than aluminum, capable of withstanding higher rotational stress.
Work condition adaptability: Suitable for large centrifugal air compressors with high rotational speed and high compression ratio, or industrial environments with higher medium temperature and trace impurities (such as in the chemical and power industries), capable of withstanding harsh mechanical and thermal loads for a long time.
Stability: The metal material has better rigidity, stronger vibration suppression ability during high-speed rotation, which helps reduce the noise of the unit and extend the lifespan of related components such as bearings.
4. Design and manufacturing features
Aerodynamic optimization: The shape of the impeller blades (such as forward inclination, backward bending, radial), inlet and outlet angles, wheel diameter, etc. are all optimized through fluid dynamics (CFD) simulation to ensure smooth airflow, reduce vortex and shock losses, and improve insulation efficiency.
Precision processing: Use five-axis linkage processing, overall forging, etc., to ensure the size accuracy and dynamic balance performance of the impeller, avoid vibration exceeding standards due to uneven mass distribution, and ensure safe operation.
Corrosion treatment: Some metal impeller surfaces will undergo chrome plating, ceramic spraying, etc., to enhance corrosion resistance and wear resistance, suitable for compressed air environments with higher moisture content or slight corrosiveness.
