scope:

This International Standard specifies methods for the leak testing of vacuum valves used for control of gas flow or vacuum pressure in a vacuum system. It is applicable to vacuum valves that can be closed to leak rates less than 1 × 10⁻⁵ Pa m³/s for trace gas. The methods employ a sealing arrangement for the valve body, which is also specified in this International Standard. The methods are suitable for the verification of valve specifications.

A valve leak rate less than the nominal leak rate specified by the manufacturer during and after the operation enables the specification of such valve operating conditions as operating pressure range, permissible pressure difference between ports, bake-out temperature or operating temperature, and life cycle.

NOTE 1 The data for large valves and valves without a valve body can vary from those obtained during delivery inspection depending on the accuracy of the attachment surface of the vacuum device.

NOTE 2 The data obtained from this procedure is based on the testing conducted on an individual unit of a vacuum valve and they can be different from those obtained during delivery inspection if the test is performed with the valve incorporated into the equipment.