Principle Of Operation Magnetic Driven Pumps are seal-less pumps that use a coaxial magnetic coupling to transmit torque to an impeller. A standard electric motor drives a set of permanent magnets that are mounted on a carrier or drive assembly. In turn, the magnets drive the inner rotor and provide the no-slip or synchronous capability of the torque coupling. | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Pump Liquid End Fluid is moved by a centrifugal pump through the use of centrifugal force. Fluid is taken into the center of the impeller through the inlet connection called Suction Eye. Most centrifugal pumps prefer a positive inlet pressure to prevent Cavitation (lack of enough positive inlet pressure to prevent liquid vaporization). This fluid is then caught by the vanes of the impeller as it spins. This rotation of the fluid mechanically by the vanes “throws” the fluid to the outside of the impeller and toward the discharge port of the liquid end of the pump. This mechanical movement of the fluid creates the discharge pressure of the pump. Variables like inlet fluid supply pressure, impeller diameter, motor horsepower and closed face versus open face all affect the flow and pressure of the pump. Each of these variables can be manipulated to achieve a desired flow and/or pressure.
Pump Magnetic Drive A magnetic drive pump uses a balanced magnetic field to create the rotation of the fluid impeller. Unlike a traditional centrifugal pump which has a direct drive connection between impeller and motor, a Mag-Drive pump eliminates the direct drive mechanism and replaces it with a magnetic field. Outer magnetic bell housing is mounted on the end of the pump shaft. This outer bell is aligned on the outside of the rear casing. The pump impeller is connected to a smaller magnet assembly and rides on an internal shaft and bushing assembly. (The liquid end parts are all isolated within the fluid head of the pump without the need for a mechanical seal.) The smaller magnet assembly is mounted within the center of the magnetic field of the outer bell housing. Although these two magnet assemblies are separated by a fluid barrier, the magnetic fields are aligned. When the pump motor is started the outer bell housing begins to rotate. As the outer bell rotates, the rotating magnetic field affects the inner impeller magnet. As the two magnets begin to turn together, the impeller begins turning and displacing fluid.
Magnetic Coupling - Principle Of Operation A magnetic coupling consists of two magnet assemblies. One is the outer assembly (the drive magnet) and the other is the inner assembly (the driven magnet). The outer assembly is connected to a motor and the inner assembly is directly attached to the pump impeller. As illustrated, at rest, the magnet components of the outer assembly are aligned with their counterparts in the inner assembly. When load (torque) is applied, the coupling deflects angularly and the magnets create a force of simultaneous attraction and repulsion. This force is used to transfer torque from the motor to the impeller. Neo-Mag pumps are therefore sealless and hermetically closed.