The principle of rotary screw air compression is really no different than reciprocating (piston) compression. Both are positive displacement machines that take in a fixed volume of air at atmospheric press.
[pdf] Rotor clearance issues or debris can lead to metallic contact sounds Loose or worn belts squeal or howl, especially under load Airflow pulsations, valve leaks, or turbulence create hissing or whistling Bolts, nuts, and mounting pads loosen over time, amplifying noise
[pdf] The reasons for the high exhaust temperature of screw air compressors : 1. High return air temperature; 2. The motor has a large heating capacity; 3. High compression ratio; 4. High condensation pressure; 5. Improper selection of refrigerant.
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