Magnetic pumps – find manufacturers and suppliers

What are solenoid pumps used for?

Solenoid pumps are a combination of a permanent magnetic drive system with common pump hydraulics. They are the practical application of magnetism and hydraulics. They use the attractive and repulsive forces between permanent magnets in the coupling halves. This is needed for non-slip and non-contact torque transmission. The components of a magnetic pump are the drive shaft, the magnet driver, the magnet carrier, the pump shaft, the pump impeller, the plain bearing and the containment can. The drive shaft transmits the pump power without slip or contact to the magnet carrier on the pump side by means of the magnet driver. This drives the pump impeller by means of the pump shaft. This is mounted in a lubricated plain bearing. The magnetic coupling and the plain bearing are lubricated by the liquid delivered by the pump. The required partial flow is taken from a point behind the impeller at high pressure or at the discharge nozzle. This then passes through cooling elements and exits through holes in the impeller, inlet on the suction side. This can also be done by separate feeding. The containment can is located between the magnet driver and magnet carrier. This separates the pumped material from the environment without leakage.

The pump housings are available in stainless steel, Hastelloy, ceramic, titanium, tantalum and other special materials. This makes them particularly resistant and durable. Gears and bearings for magnetic pumps are made of ceramic, Hastelloy, zirconia, SiC, stainless steel, ferralium, NiAg, ferro titanite, etc. Various coatings are available to ensure higher durability.

The magnetic drive pump is ideal for hazardous, toxic and odorous pumping materials. The magnetic drive pump is so interesting because the motor can be freely selected. This makes it very cost-effective.

Special forms

Special magnetic couplings are now available for gear pumps. These have a special separate, very reliable rotor bearing. This magnetic coupling is used for chemical pumps and for pumping critical media.

Some technical details

The delivery volume is between 1.28 ccm/rev and 12,000 ccm/rev. The flow rate is between 20 l/h and 170,000 l/h. Solenoid pumps have suction pressures up to 500 bar. Differential pressures range up to 120 bar. Some pumps reach viscosities of up to 1,000,000 mPas as well as temperatures of up to 300 degrees.

Areas of application

• EX-area zone 1
• EX-area zone 2
• EX-area zone 21
• EX-area zone 22
• Chemical industry
• Pharmaceutical industry
• Laboratories
• Cosmetics industry

Pumped media

• Lyes, bases, brine, acids, amino acids
• Alcohols, esters, phenols
• Additives
• Organic, inorganic chemicals
• Abrasive, corrosive media
• Liquid sulphur
• Resins, hardeners, adhesives
• Glycerine
• Isocyanates
• Asphalt, bitumen, tar
• Hotmelt
• Chewing gum mass
• Lotions, shampoos

Advantages and disadvantages

The magnetic pump only requires static seals. These are therefore less stressed and more wear-resistant than dynamic mechanical seals. In addition, there is no leakage of the pumped medium. Cavitation damage is common. In order to minimise the risk of pump damage and evaporation, special gap head designs are developed which allow either special cooling or the introduction of an insensitive barrier material (steep vapour pressure curve). Eddy current induction is reduced or completely prevented if the containment can is made of ceramic (zirconia) or plastic. This is expensive and not suitable for some operating pressures, operating conditions, e.g. pressure surges and pumped media. This type of pump requires much more technical knowledge and safety expertise. The big advantage of the solenoid pump is the complete encapsulation of the pumping material. The cost is enormous, but justified, as this is often the only technically feasible solution.

The most important areas of application are the petrochemical and chemical industries.

Conclusion

Solenoid pumps are characterized above all by their outstanding suitability for leak-free use with extremely toxic, hazardous and odor-intensive media. They are made of heat and acid resistant, stainless materials. Solenoid pumps are very costly, but they are worth the money. Because of this, the advantage of purchasing them used is undeniable. Even used, they offer a very good performance due to their robustness and durability. In continuous operation, regular maintenance and cleaning are essential, especially for pumps in these critical areas of application. If this is taken into account, solenoid pumps have a very long service life.