Hybrid can feature enhances energy-efficiency of leak-free mag-drive centrifugal pumps
05 Apr 2017
The significant benefits of using magnetically driven pumps such as zero leakage, no wastage or environmental hazards along with extended pump life with longer service intervals, are being appreciated by many end-users in the process and chemical industries. A good example of these types of pumps is the extensive range developed by M Pumps and available exclusively in the UK through pumping specialists Michael Smith Engineers. The range includes; magnetically coupled centrifugal, vane, turbine and side-channel pump options which are meeting the demands of challenging applications.
With technology advancing so are the demands from end-users in the process and chemical industries seeking effective pumping solutions for handling higher pressures, higher temperatures with improved energy-efficiency. In response to these demands M Pumps has focused attention on improving the energy efficiency of their centrifugal pumps which has led to the development of an innovative rear containment shell and now fitted as standard on their CN MAG-M Series of centrifugal process pumps.
This unique patented hybrid containment shell combines the reliability and chemical resistance of a standard inner metallic shell with the strength of a carbon fibre outer shell and can be selected for applications with liquids at temperatures up to 200ºC and system pressures up to 50 Bar. With a choice of either titanium or hastelloy C inner shell, the M Pump Hybrid Containment Shell has played a significant role in enhancing the operational efficiency and competitiveness of these pumps compared to other standard mag-drive pumps. The operating principle of mag-drive pumps involves a rotating magnetic field which is separated by a stationary metallic barrier which cuts the magnetic field and generates eddy currents that in turn generate heat. The amount of heat generated depends on the material of the barrier. Hastelloy C and titanium generate less eddy current than stainless steel while non-metallic materials generate minimal losses.
Also, the strength of a magnetic field reduces in proportion to the square of the distance from it, so the closer together the magnets, the more efficient the coupling. The M Pumps hybrid solution minimises magnetic losses by featuring a very thin barrier in either hastelloy or titanium, with a thin carbon outer shell thereby reducing the amount of heat from eddy currents and the distance between the rotating magnets. Consequently for a given duty, M Pumps hybrid technology will consume less power in operation enabling a smaller motor to be installed compared to a pump with a traditional containment shell.
In addition to the benefits of improved energy-efficiency and a more compact, space-saving solution, CN MAG-M pumps provide the important advantages of mag-drive pumps. For example, a hermitically sealed, leak-free design with no rotating seals to fail meaning reduced downtime, no cross-contamination of the pumped liquid, no wastage, no environmental hazards and improved operator safety.
Close coupled versions are also available which reduces possible alignment issues and minimises on-site space requirements. Furthermore, a choice of chemically resistant wetted materials helps to extend pump life and increase time between servicing. For critical applications secondary containment options are available.
Thanks to their leak-free design M Pumps are particularly suited to handling toxic, flammable or other dangerous liquids. Models are available for handling capacities up to 4000 m³/hr, differential heads up to 220 metres (single stage) and up to 700 metres (multi-stage) with system pressures up to 150 Bar.