Differences Between Single Stage and Double Stage Vacuum Pump

Structure:

We call this pump with one pair of rotor, cylinder, and sliding blade a single stage vacuum pump. As for a double stage vacuum pump,  it has two pairs of rotor, cylinder, and sliding blade connected in series and obtains a large compression ratio to obtain low pressure.

Working:

A single stage rotary vane vacuum pump exhausts into a working chamber inside the pump which separates the pumped gas from the oil. The compressed gas runs out and the oil returns So that this kind of pump is great for situations where rough vacuum levels are most likely. As for the cost, it is cheaper than double stage units.

As the name implies, a dual-stage rotary vane vacuum pump contains two stages of pumping in a single assembly. One is a low vacuum stage while the other is a mated high vacuum stage. High vacuum chamber drives the process gas in, and than transfer is to the low vacuum station. At the low vacuum station, the process air gets compressed to atmospheric pressure, to improve the performance of the pump. This pump is perfect for processes that demand a deeper vacuum as they offer greater pressure range.

Features:

In a single stage vacuum pump, a filter with metal mesh is installed at the inlet. It can prevent solid particles from running into the vacuum pump. And the oil separator with a switch can separate the oil and the gas efficiently. When the pump stop pumping, the suction valve can isolates the pump from the pumping system. And prevent the oil from returning to the pumping system.

While as for double stage vacuum pump, the two parts of rotor and the special design can help to increase the vacuum speed. Besides,  this double stage vacuum pump can also vacuum better than single stage one.