Mechanical seal pumps
1. Sealing of the fluid being pumped
In mechanical sealed pumps there is a mechanical seal that prevents the leakage of the fluid being pumped. However, some amount of fluid always keeps on leaking through the mechanical seal for its lubrication and cooling.
Some mechanical seals can be cooled by external fluids. In magnetic drive pumps no mechanical seal is required. There is a shell or containment part of the pump that forms a complete and sealed enclosure through which the fluid being pumped cannot leak - thus the magnetic drive pumps are sealless zero leakage pumps.
2. Wearing of the seal and maintenance
The mechanical seal comprises of moving and stationary parts which are in contact with each other. The faces and elastomers of the mechanical seal start wearing after certain period of time and the amount of fluid leaking through it keeps on increasing, having to be replaced from time-to-time.
Since the magnetic drive pumps contain no seals there is no wearing of its parts, so no replacements are required and therefore requires less maintenance.
3. Mode of driving or pump design
In traditional pumps with mechanical seals there is coupling between the driving motor and driven pump shafts for the transfer of power to the impeller.
This arrangement makes it necessary to have the mechanical seal to prevent leakage of fluid. In the magnetic drive pumps the drive shaft is surrounded by a set of magnets.
When this shaft rotates it transfers its magnetic field to the impeller shaft through the shell through which the fluid passes. Thus there are no opening involved in the magnetic drive pumps and a completely sealed enclosure is formed for the fluid.
2012-09-04
