Centrifugal Pump - Magnetically Coupled Pumps

Magnetically Coupled Pumps

Magnetically coupled pumps, or Magnetic drive pumps, vary from the traditional pumping style, as the motor is coupled to the pump by magnetic means rather than by a direct mechanical shaft. The pump works via a drive magnet, 'driving' the pump rotor, which is magnetically coupled to the primary shaft driven by the motor. They are often used where leakage of the fluid pumped poses a great risk (e.g., aggressive fluid in the chemical or nuclear industry, or electric shock - garden fountains). They have no direct connection between the motor shaft and the impeller, so no gland is needed. There is no risk of leakage, unless the casing is broken. Since the pump shaft is not supported by bearings outside of the pump's housing, support inside the pump is provided by bushings. The materials of construction of these bushings and the required clearances of the parts may restrict the kinds of fluids for which this kind of pump may be used.