HI-VAC liquid ring vacuum pumps are built to high quality standards. Reliable, heavy duty design and built to rigid standards. HI-VAC liquid ring vacuum pumps are available in different materials to suite just about any application. Standard sealing is packed gland, with mechanical seals available. With a choice of 35 models and ranging in capacity from 18m³/h to 12500m³/h at a vacuum of 25mm HG (absolute).