It should turn around smoothly, without any 'hickups' (be sure to completely shut down the air compressor!). Check the isolation of the motor windings. Should be in the mage-ohms (you need an isolation tester / high voltage ohm meter for this). Check the voltage when the compressor is running.
[pdf] Though the oil free type compressor design method is used for twin-screw steam compressor, the bearings and synchronous gears still need lubrication by pressured lubricating oil. If steam leaks into the l.
[pdf] High efficiency oil-free compressor Air-end ● The first and second level materials are stainless steel； ● High rotary speed SKF bearing； ● Special coating，270℃ temperature resistance； ● Oil jacket cooling，No scaling or dew coagulation risk； ● High precision synchronous gear. Efficient suction system
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