Gear pumps are used for a wide range of applications. For use in oil hydraulics or lubricating oil applications, it is usually sufficient to design the shaft seal using a radial lip-type sealing. Mechanical seals are also frequently used in gear pumps. However, there are also applications where the use of magnetic couplings is advisable or even necessary. This applies to the following challenges:
- The medium is toxic and leakage into the atmosphere must be avoided at all costs.
- The medium crystallizes or hardens when exposed to air humidity. Contact between the pumped medium and air humidity must be prevented.
- The pump is difficult to access for servicing. Long-term use without replacing shaft seals is necessary.
- At high inlet pressure and with an internal connection between the pump inlet and the shaft seal, a magnetic coupling has a significantly higher pressure resistance than other shaft seals, depending on the material and design of the canister.
The following information is required to design the appropriate magnetic coupling:
- Dimensions of the front connection flange and drive shaft of the pump in order to be able to design the adapter flange.
- Technical data sheet specifying the motor size, number of poles and electrical power, as well as dimensional drawings of the intended drive motors (also possible as a STEP file). This data is used to determine the size of the magnetic coupling and to define the bellhousing and the hub of the outer rotor.
- Specification of whether fixed speed or frequency converter is to be used. For frequency converter operation, specification of the speed range is needed.
- Type, temperature and viscosity of the pumped media.
- Specification of maximum inlet and outlet pressure.
