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] Fasten head end of cylinder to cylinder service stand. 2. Remove line (B). 3. Pull rod out so piston is against rod guide. 4. Connect rod to a hoist using a lifting strap. 5. Remove cap screws (A). 6. Pull rod, rod guide and piston from barrel.
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