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The MR range of pumps is specifically designed for pumping liquids that contain air or gas.These pumps are most commonly used for CIP return applications in the food, dairy, beverage and pharmaceutical industries.


The MR has a unique construction which makes it perfectly suited to pump liquids with entrained gases. The MR is a well proven Alfa Laval technology that is highly suited to these applications.

The most common application for the MR is CIP return. This application contains is a mix of liquid and gas which needs to be pumped where standard pumps have difficulty.

Made from AISI 316L stainless steel and has a robust, heavy duty design which results in a long life.

Available in 4 models MR 166S,185S,200S and 300. The range can pump up to 80 m3/Hr and pressure of up to 5.3 bar. The MR features an "External" mechanical seal for maximum hygiene and one seal can fit up to 3 models thus reducing spare parts holding.

The pump is available with both IEC and NEMA standard motors and has CE and  3A certification.

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How it works

The MR liquid ring pump works on the basis of centrifugal force, as do the Alfa Laval LKH and SolidC pump ranges. However, in the MR design the fluid is not directed into a ring or volute type casing around the periphery. Instead it passes into channels on either side of the impeller, in the front and back plate of the pump.

These side channels increase in volume as the Impeller passes the suction port. This creates a vacuum and draws liquid in. This volume is then automatically reduced at the discharge port, creating pressure and forcing liquid out, thus providing the pumping action.

A proportion of the centrifuged liquid is retained around the periphery and re-circulates, forming a "liquid ring" that is used to maintain the prime.

The combination of expansion and contraction of volume, centrifugal force and liquid ring construction increases the permissible gas content in the fluid being pumped. This in turn makes this type of pump particularly suitable for fluids with entrained gases.

Download the product models in Neutral or Native CAD file formats. It is also possible to download 3D PDF files.

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Part of a broad range of hygienic pumps

Alfa Laval offers a comprehensive range of pumps for use in hygienic applications. These include:

  •  LKH (Premium centrifugal pump) 
  •  SolidC (Standard centrifugal pump) 
  •  SRU (Premium tri-lobe rotary lobe pump)
  •  SX (Multi-lobe rotary lobe pump)
  •  OptiLobe (Standard tri-lobe rotary pump)
  •  SCPP (Circumferential piston pump)

For the biotech and pharmaceutical industry:

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