Choice of suitable valves

Vacuum technology puts great demands on the functioning and reliability of the valves, which are often needed in large numbers in a plant. The demands are fulfilled only if correct shut-off devices are installed for each application, depending on the method of construction, method of operation, and size. Moreover, in the construction and operation of vacuum plants, factors such as the flow conductance and leak-tightness of valves are of great importance. 

In addition to the vacuum valves, which perform solely an isolation function (fully open - fully closed position), special valves are needed for special functions. Typical are variable leak valves, which cover the leakage range from 10 ° cm /s (NTP) up to 1.6 10 cm /s (NTP). These valves are usually motor driven and suitable for remote control and when they are connected to a pressure gauge, the process pressures can be set and maintained. Other special valves fulfill safety functions, such as rapid, automatic cut-off of diffusion pumps or vacuum systems in the event of a power failure. For example, SECUVAC valves belong to this group. In the event of a power failure, they cut off the vacuum system from the pumping system and vent the forevacuum system. The vacuum system is enabled only after a certain minimum pressure (about 200 mbar) has been attained once the power has been restored. 

When aggressive gases or vapors have to be pumped, valves made of stainless steel and sealed with VITILAN sealant are usually used. For nuclear technology, valves have been developed that are sealed with special elastomer or metal gaskets. We will be pleased to provide further design information for your area of application upon request. 

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