ISO 1608-2:1989

Vapour vacuum pumps — Measurement of performance characteristics — Part 2: Measurement of critical backing pressure

The considered method of measurement deals with vapours jet vacuum pumps, diffusions pumps and diffusion-ejector pumps. The dependence of the performance of these pumps on the backing pressure can only be completely described be means of a curve relating the inlet and backing pressure over the range of operation. The recommended test dome and the principle of the test equipment are illustrated.