Try to turn the compressor by hand. It should be possible to turn it around. It should turn around smoothly, without any 'hickups' (be sure to completely shut down the air compressor!). Check the isolation of the motor windings.
[pdf] Driven pile and helical or screw pile foundations are good alternatives that have been used successfully, even for very large reciprocating compressor packages. A pile foundation has the advantage of lower costs and shorter installation time compared to concrete block foundations.
[pdf] use caustic soda solution (Concentration 8-10%) Heat to 60℃ and soak the handpiece for 24 hours. cooler Use a high-pressure water gun (pressure>15MPa) to back-flush the copper tube. replacement All-oil sealing ring Avoid corrosion by residual cleaning agents.
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