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. If the voltage drop significantly when the compressor starts/runs, you have a bad connection somewhere.
[pdf] Flange end ball valves are widely used in mining due to their ability to provide precise fluid control and tight shutoff in high-pressure mining environments with hydraulic valves.The floating ball mechanism allows the ball to move slightly under pressure, pressing against the downstream seat for a secure seal.
[pdf] Install the valve with proper positioning of the flow arrow. Support and align adjacent piping and the vale. Install lubricated flange bolts. Hands tighten, and then torque the bolts using the crossover flange bolt-tightening method to load the bolts evenly, and eliminate concentrated stresses.
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