Molecular pump

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Molecular pump - a kind of vacuum pump, invented by Gaed about 1916.

The pump has a rapidly rotating shaft (tens of thousands of revolutions per minute), into which the gas inlet is injected through the pump inlet, and a properly stowed stator directs the particles toward the pump outlet. The rapid rotational motion of the shaft, which translates into high linear velocities at its periphery (up to several hundred m / s, and therefore comparable to the velocity of the gas molecules at room temperature), gives the incident particles an additional speed towards the pump outlet.

The first molecular pumps were inefficient and did not find a wide application, although the vacuum reached 10 Tr.

The only efficient type of molecular pump is a pump with a screw-shaped stator, which in some way increases the pumping speed. Molecular pump requires an initial vacuum of 0.1 Tr. It is rarely used due to better parameters of turbomolecular pumps.

wiki

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