If your industrial chiller still relies on a mechanical seal pump, it may eventually leak refrigerant due to the aging of its sealing components. Therefore, most high-performance chillers now use magnetic drive pumps from internationally renowned brands. So, what are their benefits? What challenges will they face? What is the difference with mechanical seal pumps?

What is a magnetic drive pump?

A magnetic drive pump is a type of centrifugal pump. It does not use a mechanical seal, but uses a high-strength isolation sleeve to isolate the motor and the liquid, and transmits power through magnetic coupling. During operation, the motor transmits power to the external magnet, which generates a magnetic field when it rotates. This magnetic field then uses the magnetic force to drive the internal magnet to rotate, and the internal magnet, in turn, drives the impeller to rotate.
 
This coordinated movement enables efficient fluid transport. Except for the internal sliding bearing, there is no direct contact between other movable parts, which reduces mechanical friction and wear on bearings. Its most prominent advantage is that it will not leak, which makes it very suitable for pumping hazardous liquids.

Magnetic drive pump and mechanical seal pump

Structure

• Magnetic drive pump: The main structure of the magnetic drive pump consists of a pump body, a motor, an outer magnetic rotor, an inner magnetic rotor, a isolation sleeve, an impeller and a bearing. The isolation sleeve is between the inner magnetic rotor and the outer magnetic rotor, which can completely separate the liquid and the motor to prevent liquid leakage.
 
• Mechanical seal pump: The main body of the mechanical seal pump consists of a pump body, a motor, a mechanical seal assembly, an impeller and a bearing. The motor can drive the bearing to drive the impeller to rotate. Its mechanical seal is generally installed at the position where the shaft passes through the pump body.

Sealing method

• Magnetic drive pump: The magnetic drive pump uses a fully sealed structure, and its seal is the isolation sleeve. Because the outer magnetic rotor can drive the inner magnetic rotor through magnetic coupling, there is no need for a connector between the two. The isolation sleeve between the two is stationary, and almost no leakage can be achieved.
 
• Mechanical seal pump: The sealing of the mechanical seal pump is achieved through the contact between the moving ring and the static ring. The static ring is fixed in the pump body or the sealing chamber. The moving ring rotates with the pump shaft and is tightly attached to the static ring to form a seal. However, if the two are not tightly fitted, or the spring providing axial pressure fails, leakage will occur.

Wartung

• Magnetic drive pump: The seal of the magnetic drive pump is an isolation sleeve, which is very strong and does not need to worry about leakage, so the frequency of checking the seal is very low. Daily maintenance only needs to check whether there is demagnetization, bearing wear or isolation sleeve rupture. Compared with mechanical seal pumps, its maintenance is simpler and the cost is lower.
 
• Mechanical seal pump: The mechanical seal is a consumable component and must be replaced regularly. However, when replacing the seal, the pump must be disassembled, which is time-consuming.

Kosten

• Magnetic drive pump: The purchase cost of the magnetic drive pump is higher than that of the mechanical seal pump. However, it has a longer service life, requires less maintenance, does not need to replace the seal frequently, and has lower operating and maintenance costs. If used for long-term projects, it is more cost-effective.
 
• Mechanical seal pump: The price of a mechanical seal pump is lower, but the seal needs to be replaced frequently. Once a leak occurs, it will incur greater repair costs and downtime costs.

Schlussfolgerung

Compared with mechanical seal pumps, magnetic drive pumps are more reliable, which is why LNEYA chillers use them. The magnetic drive pumps in our cooling system are all produced by internationally renowned brands and have higher performance.
 
If you want to buy an industrial chiller, our team can help you configure the specifications and brands of various components according to your application and budget, and provide you with a more cost-effective chiller system.