Sealed pump: operating principle

It happens that it is necessary to prevent liquid from entering the pump, and also to prevent leakage. For this, a sealed pump is used. Its main feature is that the motor shaft and pump are not connected to each other. That's why you do not need to make holes in the case. Rotation occurs with the help of magnets fixed on the shafts of the pump and motor.

General information

Hermetic pump appeared in the world thanks to American scientists in the late 40's. Until then, pumps had low efficiency. This was due to the fact that the magnets did not touch each other, but were distributed under the body. Because of its large thickness, magnetic losses occurred. Modern technologies can significantly reduce these losses and increase the efficiency of the unit.

Chemical sealed pumps are used for pumping aggressive liquids. The cost of such equipment is significantly overestimated. But the workflow is much safer. In addition, you do not need to engage in pump compaction. Since the structural elements are made of chemically resistant metals, there is no point in using the pump to pump the usual liquid.

Device

As stated earlier, there are no holes in the element design, and therefore there will be no leaks.
Looking at the hermetic pump in a section, you can see that it works by using two magnets. One of them is located on the pump shaft, and the other one is on the engine. Therefore, energy is transmitted at a distance. Its rear part is integral, since the device shaft is located directly in the housing.

Advantages

The hermetic pump has the following advantages:

1. No leakage when pumping liquid. Even the best seals allow a certain number of leaks. To prevent them from appearing, it is necessary to lubricate the O-rings. To eliminate them completely, you should use a special liquid, which is very expensive. The hermetic pump is much easier to maintain and operate.
2. Ease of maintenance. Sealing on other equipment quickly wears out, so it becomes necessary to repair or replace it. In a sealed pump, magnetic elements have a long service life, reaching a mark of 100 years.

Device Properties

These characteristics can not be attributed to either positive or negative sides. Among them are:

1. Transmission performance. Previously, the pump performance was significantly reduced due to the location of the magnets between the thick walls of the housing. Thanks to modern technology, its efficiency is 100%.
2. The temperature of the liquid. The hermetically sealed pump is capable of pumping liquid at a temperature of + 200 ° C. When using additional elements, it can increase to + 400 ° C. It all depends on the type of seal.
3. The cost. Compared to other models, the price of a sealed element is quite high. It depends on such expensive equipment as magnets, and is in the range of 50 thousand to 300 thousand rubles. By the way, in recent years NPC "Hermetic Pumps" has sharply reduced the cost of its products by 40%.

disadvantages

Among the cons are:

• Quick breakdown of equipment in case of solid particles;
• Inability to work when idling;
• Work only in the established parameters;
• If metal elements are located near the pump, then the couplings are demagnetized and, consequently, the performance is reduced.

Sealed pump: operating principle

The principle of operation of hermetic equipment is simple. The pumped liquid enters the pump design through the inlet pipe. With the help of rotating wheels, a sufficient amount is produced for pumping the fluid from one medium to another. The electric motor and the pump are located on the same shaft. The rotor space is filled with water. One part is used as a lubricant for bearings. Also pumped liquid serves to cool the structural elements.

Between the engine and the working environment a shielded thin tube with a sealed glass is installed. In the design of the electric motor and the rotor, sliding bearings are provided . In order to be easy to monitor their condition, a screen is installed on the front panel of the sealed pump.

Reviews

Many users of this device are completely satisfied. It has a high capacity, so you can quickly pumping fluid from one place to another. A significant advantage is the absence of leaks, as well as a long service life. Among the negative sides users allocate high cost of the device. A good hermetic pump costs about 200 thousand. Not everyone can afford this amount. Another disadvantage is the immunity of solid particles. If the latter come in contact, some of the pump components fail. In order not to spend additional funds for repair or replacement of structural elements, it is necessary to monitor the pumped liquid.

Conclusion

A sealed pump appeared in the late 1940s, and since then has pleased many users. Every year he was getting better. Therefore, today we have high-quality and useful equipment. As a rule, they are used for pumping aggressive liquids.