Global Pumps , a major distributor of Techniflo magnetic drive pumps in Australia and New Zealand explains the difference between pumps with mechanical seals and sealless magnetic drive pumps.
Mag drive pumps are superior to mechanical seal pumps in various industrial applications with advantages including sealing efficiency, low maintenance requirement from less wear, better pump design and excellent corrosion resistance.
Sealing of the fluid being pumped
Mechanical seal pumps consist of a mechanical seal that prevents the leakage of the fluid being pumped. However, some amount of fluid continues to leak through the mechanical seal for its lubrication and cooling.
Magnetic drive pumps do not require mechanical seals, with the shell or containment part of the pump forming a complete and sealed enclosure that prevents leakage of the fluid being pumped.
Seal wear and maintenance
The mechanical seal comprises of moving and stationary parts in constant contact with each other. The faces and elastomers of the mechanical seal start wearing after a certain period of time with the leaking fluid increasing in quantity till the parts are replaced.
Since the magnetic drive pumps do not contain seals, there is no wearing of parts, eliminating any need for replacements and resulting in less maintenance.
Mode of driving or pump design
Traditional pumps with mechanical seals consist of a coupling between the driving motor and driven pump shafts for the transfer of power to the impeller.
The drive shaft in magnetic drive pumps is surrounded by a set of magnets. The rotating shaft transfers its magnetic field to the impeller shaft through the shell through which the fluid passes. There is no opening in the magnetic drive pumps and a completely sealed enclosure is formed for the fluid.
Type of fluids being pumped or application
While mechanical seal pumps can be used for pumping hazardous fluids, some leakage of fluid may occur.
Magnetic drive pumps are zero leakage pumps, capable of highly reliable pumping of hazardous corrosive fluids, aggressive fluids, difficult to seal fluids, expensive fluids, pure fluids and slurries. Magnetic drive pumps are made of non-metallic components that offer excellent corrosion resistance.