Robust Centrifugal Pumps for Optimum Reliability


The FreFlow range of self-priming centrifugal pumps have excellent self-priming abilities and are particularly suited to a wide range of applications which require the transfer of low viscosity, contaminated liquids or those containing gas or air.

Robust Centrifugal Pumps for Optimum Reliability

FreFlow self-priming centrifugal pump from JP Pumps (photo: JP Pumps Ltd).

Recently introduced by JP Pumps (a division of Johnson Pump AB), FreFlow pumps are based on the injection principle, with a semi-open or closed impeller and a mechanical seal in the oil chamber. Their self-priming ability prevents the pump from running dry, ensures smooth, easy operation and eliminates the need for a separate vacuum pump or other associated equipment.

The design of FreFlow pumps eliminates the need for a non-return valve in the inlet, a feature which contributes towards unparalled reliability. This, combined with a back pull-out system, inspection and cleaning cover, ensures easy maintenance because the pump does not need to be disconnected and removed from the pipework.

Other features and benefits include an oil chamber located behind the mechanical seal which lubricates the seal faces when priming, thus preventing the seal from running dry. This also helps to prevent crystallization between the seal faces to ensure longer seal life and reduces the risk of process downtime.

The FreFlow range consists of 20 pumps with connections from 32mm to 150mm, providing capacities up to 300m3/hr at heads up to 70 metres. Their self-priming ability is up to 7 metres and they are suitable for handling liquids with a viscosities up to 150 mPa.s.

The basic pump is available in cast iron or bronze and a stainless steel version is ideal for handling aggressive, corrosive and environmentally harmful liquids. Typical applications for the pumps are in the chemical and pharmaceutical industries, oil, gas and electricity generation, paper, plastic, paint and metal finishing.

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