BM Booster Modules

Grundfos BM booster modules are horizontal, sleeve-enclosed high-pressure pumps built for membrane systems. ForeverPure lists 159 BM configurations.

How a BM differs from a surface pump

A BM is an SP submersible pump element sealed inside a pressure sleeve and mounted horizontally. The system pressure is contained by the sleeve, not by the pump housing, which is what lets a compact module operate at pressures that would need a far heavier surface pump. The water flows through the sleeve and cools the motor on the way.

The result is a high-pressure, high-efficiency booster in a small footprint, in stainless throughout — which is why BM is the standard interstage and feed booster on reverse-osmosis skids.

Typical applications

Seawater and brackish-water RO — membrane feed and interstage boosting
Energy-recovery circuits — pairing with pressure exchangers and turbochargers
Filtration and industrial process at elevated pressure
Boosting from low-pressure supply where a surface pump would cavitate

Which BM variant? Standard BM covers general high-pressure boosting. BMhp is the high-pressure seawater variant built for SWRO duty, in 904L or duplex stainless for chloride resistance. Match the material to the water, not just the pressure.

Common questions

What is a Grundfos BM booster module?

A submersible pump element inside a pressure sleeve, mounted horizontally. It delivers high pressure in a compact stainless package, and is designed for membrane systems.

What is the difference between BM and BMhp?

BMhp is built for seawater reverse osmosis — higher pressure capability and chloride-resistant alloys. Standard BM suits brackish and general high-pressure boosting.

How do I read a BM model number?

BM 17-4 is the 17 m³/h flow class with four stages. Stage count sets the pressure at that flow.

Are BM modules made to order?

Most are. Each product page shows current availability and, where Grundfos has committed one, a dispatch date.

ForeverPure Corporation is an authorized Grundfos distributor. Send us a duty point or an existing model number and we will confirm the right configuration before you order — contact us.