The UHV and XHV All-Metal Leak Valve for Precise Flow Control

Descriptive image displaying three Leak Valve configurations

ANCORP’s most recent product expansion of 8 VAT vacuum valves saw the addition of the VAT Series 590 All-Metal Variable Leak Valve. This series offers a variety of novel features that combine to create a valve capable of achieving precise manipulation of very small gas flows and performing beyond ultra-high vacuum (UHV) applications and into extreme high vacuum (XHV) applications.

Leak valves offer vacuum users the ability to create an adjustable leak for use in system procedures that require controlled gas flows.

All-Metal Construction

The Series 590 leak valve features an all-stainless steel body and seal. An all-metal seal ensures the valve can withstand demanding UHV and XHV vacuum environments. Compared to an elastomer-sealed valve, a metal seal is less resistant to fatigue during valve actuation and operates at a more expansive temperature range. In addition, the 590 all-metal leak valve’s “hard on hard” metal seal lasts the life cycle of the valve: 400,000 control life cycles and 10,000 leak-tight closing cycles.

Gold Plating

To further improve the construction of an all-metal leak valve, the 590 valve’s sealing metal diaphragm is gold-plated. Gold plating offers the sealing surface of the valve protection against mechanical degradation because of the metal’s resistance to fretting, the wearing of a surface due to friction. Gold also belongs to a group of metals unlikely to oxidate. This characteristic results in the diaphragm’s surface being highly resistant to corrosion caused by aggressive gases and chemical byproducts. This design consideration makes the valve an industry standard for gas-dosing processes in mass spectrometry, gas analysis, high-energy physics, thin film coating, and more.

Actuation

The all-metal fine dosing valve is adjusted using a unique control designed to grant increased precision on actuation. This precision grants users of the VAT valve series 590 reproducible settings for regulating very small gas flows in the 1· 10-10 mbar ls-1 to 500 mbar ls-1 range. This control is available in both manual and pneumatic actuation modes where the pneumatic version is controlled with a stepper motor.

The ability to withstand high temperatures can be essential for your desired use of the all-metal leak valve. As mentioned, one of the benefits of an all-metal construction involves the ability of the valve to operate in a broader range of temperatures. While this remains true, the actuation method chosen for the valve will affect the upper limit of this temperature range.

Temperature Considerations

For example, using an integrated pneumatic controller has a bakeout temperature of 50 C compared to its manually actuated counterpart. As a solution, if pneumatic actuation is a priority for your valve application, the valve has the option of being pneumatically actuated with a detachable regulator to obtain bakeout temperatures to 300 C. 

Explore the standard offering of Series 590 All-Metal Leak Valves at https://ancorp.com/product-category/high-vacuum-valves/vat-leak-valves/. For more information about choosing the best valve for your application, contact one of our application engineers today.