Magnetic drive pumps are designed to be driven by the force of magnets. Because of this, pumps of this kind do not have the shaft coming out of the pump casing, hence there is no need for shaft sealing devises such as gland packing or mechanical seals.
With magnetic drive pumps, an external magnet is placed on the drive shaft and responsible for transmitting motion to an internal magnet that connects to the impeller(s). Impeller(s) rotates and moves fluid through the pump. Both magnets are separated by a rear casing that creates what is known as a hermetic containment of the liquid with no access to the outside.
We find Magnetic Drives on various pump types such as end suction centrifugal pumps, self-priming multistage pumps, vacuum pumps, etc.
There are distinct pros and cons that should be fully understood before making the choice between the conventional driven and magnetic driven pumps.
- Based on design of magnetic drive pumps there is extremely low risk of fluid and vapor emissions from being leaked. As a result, people working on or near the pump are not exposed to dangers from hazardous, corrosive, flammable and/or explosive fluids, and other toxic chemicals. In addition, expensive liquids are not wasted.
- Magnetic drive pumps are also reliable. When choosing a reliable brand, you will have confidence the pump will operate as specified.
- A pump of this type requires very little maintenance. The primary reason is that the design is actually quite simple. In fact, when used for normal operations it is common to see magnetic drive pumps go 10 years or longer before needing any kind of repair. Even then, repairs are often inexpensive.
- Another huge benefit associated with magnetic drive pumps is because of an easy coupling there is no need for an alignment of the pump or motor
- For applications that involve solids, even a small percentage, magnetic drive pumps are not suitable because they only work with clean liquids free of solids.
- Magnet drive pump requires higher power absorption than conventional pump.
- From a cost perspective, magnetic drive pumps tend to be more expensive however because maintenance is very low a quick payback can also be attained.