Cryopump

A cryopump is a vacuum pump that condenses a gas or vapour on a cold surface.

Related Topics:
Vacuum pump - Gas - Vapour

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In small industrial stand-alone cryopumps the gas is condensed on a cold head. The cold head is cooled by a cryocooler and is protected against heat radiation by a cooled baffle which serves in the same time as pumping surface for water vapour. The assembly is installed into a vacuum vessel equipped with a standard flange.

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In order to enhance the uptime of the cryopump, the cold head is coated with a highly adsorbing material like activated charcoal or a zeolite.

Related Topics:
Activated charcoal - Zeolite

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The operation of a cryopump is intermittend and requires a regeneration (heat up) once the condensation/adsorption capacity has been reached. Cryopumps provide hydrocarbon free vacua.

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Sorption pumps are a type of cryopump that is often used as roughing pumps to reduce pressures from the range of atmospheric to on the order of 0.1 Pa (10-3 Torr), while lower pressures are achieved using a finishing pump (see vacuum). As the sorbent saturates, the effectiveness of a sorption pump decreases, but can be recharged by heating the zeolite material (preferably under conditions of low pressure) to a temperature near but below the breakdown point of the zeolite material's porous structure.

Related Topics:
Pa - Torr - Vacuum - Sorbent

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