Boyser LB-S

Boyser LB-S rotary lobe pumps are intended for compact industrial transfer duties where viscous, solids-laden or shear-sensitive fluids must be moved with controlled positive-displacement flow. The range is used across wastewater, process industry and selected food-related applications where self-priming capability, reversible operation and low-shear handling can simplify the process. The two current principal sizes, LB-S/70 and LB-S/90, cover duties up to 40 m³/h.

Two synchronised rotors move fluid through the pump chamber while a precision timing-gear system controls rotor phasing. AxFlow lists elastomer-coated rotors in NBR, EPDM and Viton/FKM as well as AISI-431 stainless-steel rotors, allowing the pumping element to be matched to the media. The rotor geometry is constructed to maximise sealing area while permitting large particle passage, and stainless-steel axial wear liners protect the pump casing and can be replaced when worn.

Current AxFlow data gives a family capacity up to 40 m³/h and differential pressure up to 10 bar. The LB-S/70 is published at up to 30 m³/h and 10 bar, while the LB-S/90 reaches up to 40 m³/h and 6 bar; the family page also lists particle passage up to 50 mm depending on configuration. Maximum published fluid temperature is 80 °C with elastomer-coated rotors and up to 120 °C with stainless-steel rotors, subject to the exact seal and material selection.

Maintenance is supported by front access to the pumping chamber, replaceable wear liners and a separation chamber between the wet end and gearbox. These features can reduce the cost of wear by protecting larger pump components and make inspection easier during planned service. AxFlow can help confirm the correct LB-S size, rotor and seal materials, drive speed, spare parts and service plan for the application.