Rotary plunger pumps

Pumps which operate with periodically increasing and deaeasing pump cham-ber volumes (rotary vane and rotary plunger pumps also trochoid pumps)... 

Shown in Fig. 2.9 is a sectional view of a rotary plunger pump of the single block type. Here a piston (2) which is moved along by an eccentric (3) turning in the direction of the arrow moves along the chamber wall. The gas which is to be pumped flows into the pump through the intake port (11), passes... 

The motors supplied with the rotary vane and rotary plunger pumps deliver enough power at ambient temperatures of 12 °C and when using our special oils to cover the maximum power requirement (at about 400 mbar). Within the actual operating range of the pump, the drive system of the warmed up pump needs to supply only about one third of the Installed motor power (see Fig. 2.11). 

Ethanoic acid is to be pumped with a rotary plunger pump. 

E 250 (single-stage rotary plunger pump, operated without gas ballast). In... 

Region A Single-stage, rotary plunger pumps without gas ballast inlet. 

This requirement is valid in the whole working region of the single-stage rotary plunger pump - hence, at total pressures between 10 and 1013 mbar. 

Region B Single-stage rotary plunger pumps with gas ballast and an inlet condenser. 

As there is merely a compression between the Roots pump and the rotary plunger pump, the following applies here too ... 

Fig. 6.2. Internal-vane, external-vane, and plunger-type rotary vacuum pumps. It will be noted that the internal-vane pump involves a rotor concentric with the drive shaft, but which is off-center with respect to the stator. By contrast, the external-vane and rotary-plunger pumps have a rotor which is asymmetric with respect to the shaft however, the shaft is centered in the stator. All three involve close tolerances, so the high-vacuum performance is impaired by particles of dirt or corrosive gases. Some pumps are partially constructed from soft die-cast metal, which is eroded by mercury. Special corrosion-resistant pumps and inert flourinated pumps are used in the semiconductor industry.

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