forepumpun
Forepumpun is a term used in vacuum technology to denote the forepump, or backing pump, which initially evacuates a chamber from atmospheric pressure down to the rough-vacuum range. It functions as the first stage in a two-stage pumping system, enabling a higher-vacuum pump such as a turbomolecular or diffusion pump to achieve much lower pressures.
Common forepump types include oil-sealed rotary vane pumps, dry scroll pumps, and diaphragm pumps. Oil-sealed vane
Operating principles vary by type but share the goal of reducing chamber pressure from atmospheric levels
Applications of forepumps span scientific instruments such as mass spectrometers and electron microscopes, as well as