Provided is a variable-capacity oil pump capable of stably securing a required pump discharge volume and discharge pressure even if an oil filter has clogged or an electromagnetic valve has malfunctioned.

The rotor set is laterally delimited by side plates which have a pump suction opening and a pump pressure opening which run substantially in the shape of a circular arc.

A pump specially positioned with respect to pump inlet and pump outlet in pipeline sections are used to increase fluid velocity in pipeline sections where gas can accumulate.

absolute outlet pressure at pump outlet (kPa

discharge pressure from the working pump

Discharge apparatus for use with a pump the pump including a pump casing (32) and a discharge outlet (60).

A controlled or regulated pressure valve (24) is allocated to said positive displacement circulation pump (18) on the delivery side.

The pump device (1) can be used as a metering pump and as a feed pump with only minor pressure fluctuations.

A discharge-pressure reduction unit reduces the discharge pressure of a charge pump.

The inlet (32, 34) of the control valve (11) is connected to the delivery side of a presupply pump.

In this way, the delivery volume of the pump is controlled.

A fluid outlet line (44) is connected to receive fluids from the gas pump outlet (24) and the multiphase pump outlet (38).

This renders a separate delivery pump for the high pressure pump unnecessary.

The beginning of the pumping can be adjusted on the first piston (70) and the end of the pumping can be adjusted on the second piston (73).

pressure head at CVS pump outlet (PPO