3 Product description
3.1 Function
The HeptaDry screw pumps function according to the double screw-pump principle. Two screw rotors
rotate in the compression chamber. The medium to be pumped is trapped between the individual screw
coils, compacted and transported to the gas outlet. During the compression process, the two screw ro-
tors do not come into contact with each other or with the suction chamber.
Fig. 2:
Operating principle
Operation of this screw pump is instigated with each occurrence of intake pressure between atmos-
phere and final pressure. Despite contactless operation of the screw pump, no operating fluid, such as
oil or water, is necessary within the working chamber. A gas ballast valve, sealing gas device and/or
silencer can be installed at the gas exhaust, depending on the respective application.
10
8
7
1
2 3
4 5
6
11
12
13
14
15
16
17
18
19
9
20
Fig. 3:
Structure of the vacuum pump
1
Vacuum connection
11
Thermal circuit breaker
2
Thermometer
12
Drain valve
3
Safety valve
13
Drain screw
4
Filler screw
14
Exhaust connection
5
Eye bolt (3x)
15
Rubber-metal bumper (4x)
6
Motor terminal box
16
Cooling water inlet
7
Cooling liquid filler screw
17
Plate heat exchanger
8
Closing screw for screw rotors
18
Cooling water outlet
9
Cooling liquid pump
19
Magnetic sealing plug/drain screw
10 Sight glass
20
Sight glass
3.1.1 Water cooling
An integrated water pump ensures an evenly distributed temperature within the pumping system. The
temperature controller is fitted before the heat exchanger in the cooling circuit. If the cooling liquid tem-
perature exceeds 55 °C, the temperature controller opens (mechanical opening) and allows the cooling
liquid to flow into the heat exchanger.
3.1.2 Temperature monitoring
The switching temperatures are dependent upon the pump size and the type of cooling system. Tem-
perature monitoring prevents overheating and potential blockages in the screw pump.
Product description
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