Working Principle of a Double-Acting Vane Pump

What Is a Double-Acting Vane Pump?

A double-acting vane pump is a positive displacement pump in which:

• The rotor rotates inside an elliptical cam ring

• Multiple sliding vanes divide the space into sealed chambers

• Two suction zones and two discharge zones are formed during each revolution

As a result, the pump completes two pumping cycles per rotation.

Working principle

1.  Rotor Rotation

When the pump shaft rotates:

• The rotor drives the vanes to rotate

• Vanes slide outward due to centrifugal force and hydraulic pressure

• Vanes stay in contact with the cam ring inner surface

This forms multiple sealed chambers between adjacent vanes.

2. Suction Process

When chambers move toward the expanding section of the cam ring:

• Chamber volume increases

• Pressure decreases

• Hydraulic oil is drawn into the pump through the inlet port

This completes the suction phase.

3. Discharge Process

When chambers move toward the contracting section of the cam ring:

• Chamber volume decreases

• Oil is compressed

• Pressurized oil flows out through the outlet port

In a double-acting vane pump, two suction and two discharge processes occur during each rotation.