Very fast-opening UHV gate valve

Very fast-opening gate valves offer the possibility to study fast processes in vacuum. For a dynamic vacuum primary standard where the pressure shall be reduced from 100 to 100 Pa in a well-defined manner within 1 s, a very fast-opening DN40 gate valve was developed. The opening time was investigated by a high-speed camera with 10 000 f/s for a differential pressure across the valve of 100 kPa to vacuum and zero differential pressure at two different absolute pressures. In all cases the area opening time of the full diameter was about 4.6 ms.