screw compressor oil safety switches

[seanf]

On screw compressors with none pumped oil feeds relying on discharge pressure only, other than oil flow switches, what other safety devices have you come across? Mainly thinking about when theres no or little oil in the seperater.

Cheers

[RANGER1]

Seanf,
Oil level switch, no oil level then no oil.
oil flow switch,
discharge to suction differential,
discharge to oil header differential,
cold start valve to build up differential quickly,
discharge temperature as no oil for cooling cuts out pretty quickly.
low oil filter differential pressure
high oil filter differential

A lot of combinations can be used, but oil level pretty important.

[seanf]

Cheers Ranger.

Should have said, mainly thinking in terms of when theres no or little oil in the seperater.

[seanf]

Seanf,
Oil level switch, no oil level then no oil.
oil flow switch,

discharge to suction differential, Just for sufficent pressure when you have oil, or do you start getting discharge gas blowing back to suction giving a low diff when theres no oil to block clearances?

discharge to oil header differential,
cold start valve to build up differential quickly,

discharge temperature as no oil for cooling cuts out pretty quickly, Would you be expecting to see some damage caused though if it was to get to the point where discharge temp goes high from lack of oil?

low oil filter differential pressure, Would that be for a blown out filter element, or for discharge gas passing through the filter element to easily?

high oil filter differential

A lot of combinations can be used, but oil level pretty important.

Cheers Ranger.

Sean