Liquid Ring Pumps

Every model has a specified service liquid flow on its data sheet — it is what forms the sealing ring and carries away compression heat. Too little water and the pump loses vacuum and overheats; too much wastes water and can cause cavitation noise. Recirculating the water through a heat exchanger is the usual way to cut consumption.

The vapour pressure of the service liquid. With 15 °C water the practical floor is around 33 mbar; warmer water raises it, and colder water or a low-vapour-pressure liquid lowers it. If you need better than that, add a gas ejector stage or a Roots booster ahead of the pump.

This is exactly what it is good at — the liquid ring tolerates carryover of liquid and vapour that would destroy a dry or oil-sealed pump. For corrosive duty specify stainless steel or bronze wetted parts and a compatible service liquid; for explosive atmospheres specify the ATEX version.

Single-stage covers most industrial duty down to roughly 130 mbar; two-stage reaches closer to the water vapour limit and holds capacity better at low suction pressure. If your process sits at the deep end of the range most of the time, two-stage pays for itself in shaft power.

The 2BE, 2BV and CL families are built to the same duty points and connection dimensions as the corresponding Nash and Siemens units, and we also supply wear parts for those originals. Send the nameplate data — model, speed, capacity and connection size — and we will confirm the equivalent and any adapter needed.