Alfa Laval OptiLobe Rotary Lobe Pump

The OptiLobe is the rotary lobe pump you specify when the duty is hygienic but not extreme. Alfa Laval calls it the cost-effective alternative for general applications that need gentle product treatment and easy servicing. It is aimed at the dairy, food, beverage, and home and personal care industries.

The ceilings are what decide it. The range reaches 77 m³/h and 8 bar differential, with a maximum process and CIP temperature of 130°C that depends on rotor selection, across 10 pump head displacements built on five gearbox modules. Connections run from 25 mm to 100 mm. The trade-off is plain: every model in the range stops at 8 bar. If your duty needs more pressure, more flow, a higher temperature, or the ultra-clean biotechnology and pharmaceutical specification, the Alfa Laval SX is the pump in the same family that goes further. Alfa Laval rates it to 115 m³/h, 15 bar and 150°C.

The build is all stainless where it counts. Media-contacting steel components, including the rotor case, front cover, rotors and rotor nuts, are W. 1.4404 (AISI 316L), finished internally to Ra ≤ 0.8. The gear canister, base plate, coupling guard and feet are stainless too, which is what Alfa Laval means by a paint-free exterior. Product-wetted elastomers are EPDM as standard, with FPM available as an option. You can take the pump bare shaft, or on a base plate with coupling, guard, gear motor and shroud.

Alfa Laval gives an extended three-year warranty on the OptiLobe covering all non-wear parts, conditional on genuine Alfa Laval spare parts being used. Channel Pumps supplies the OptiLobe and sizes it against your duty point.

A gear train in the gearbox drives the two rotors and keeps the tri-lobe profiles accurately synchronised, so nothing inside the pump head touches. The counter-rotating rotors create a partial vacuum at the inlet, and atmospheric or other external pressure pushes fluid into the pump chamber. As the rotors turn, each dwell forms an expanding cavity that fills with product. As the rotor blades re-engage, that cavity closes and displaces the product into the outlet port.

Shaft support is a rigid one-piece bearing housing on heavy-duty L10 tapered roller bearings. That holds the shafts steady under load and keeps the rotors off the rotor case, which is the wear that ends a lobe pump early. Rotor case cusps are cut back for full drainability and product recovery, and the timing gear is straight-cut so retiming is straightforward when it is needed.

The seal is the part to think hardest about, because it is the weak point in almost any pump. The OptiLobe uses the Alfa Laval EasyFit single mechanical seal, self-setting and fully front-loading, with a carbon rotary face against a stainless steel stationary face. Silicon carbide/carbon and silicon carbide/silicon carbide face combinations are options. A single-flushed version is available, limited to 0.5 bar flush pressure on about 0.5 l/min of water through a BSPT or NPT connection. That matters because a mechanical seal is lubricated by the liquid it runs in. Alfa Laval's instruction manual lists a pump allowed to run dry as a cause of seal failure, and the remedies it gives are to make sure the system cannot do it and to fit a flushed mechanical seal. Treat dry running as something you design out, not something the pump absorbs.

On hygiene, Alfa Laval states that the OptiLobe conforms to CE directives and to EHEDG, 3-A and FDA hygienic standards. The wording in its own range brochure is worth being precise about: the pump is certified according to European Hygienic Engineering & Design Group (EHEDG) protocols for full cleanability, the range conforms to 3-A sanitary standards, and all relevant components are FDA-compliant. Defined compression elastomers and an optimised seal face location are the design features behind that, and the seal faces sit in direct contact with the product so cleaning-in-place reaches them.

The certification has two practical consequences, both set out in the instruction manual. EHEDG approval applies to specific process connection and gasket combinations rather than to the pump in isolation: DIN11851 with the ASEPTO-STAR k-flex or SKS EHEDG gasket system, or Tri-clamp with the Combifit T-Ring gasket. And Alfa Laval asks you to develop and verify the CIP regime during commissioning on your own product, holding a minimum flow velocity of 1.5 m/s. Specify vertical porting if drainability matters. Say what your connection standard is when you enquire, because it decides whether the certification you are relying on actually applies.