It so happens that it is necessary to prevent liquid from entering the pump, and also to prevent leakage. To do this, use a sealed pump. Its main feature is that the motor shaft and the pump are not interconnected. That is why there is no need to make holes in the case. The rotation occurs with the help of magnets mounted on the shafts of the pump and motor.
General information
A sealed pump appeared in the world thanks to American scientists in the late 40s.
Until then, the pumps had low performance. This was due to the fact that the magnets did not touch each other, but were distributed under the body. Due to 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 overstated. But the workflow is much safer. In addition, there is no need to seal the pumps. Since the structural elements are made of chemically stable metals, it makes no sense to use a pump to pump ordinary liquid.
Device
As mentioned earlier, there are no holes in the design of the element, which means there will be no leaks.
Looking at the sealed pump in the context, you can see that its work is carried out using two magnets. One of them is located on the pump shaft, and the other on the engine. Therefore, energy is transmitted from a distance. Its back is integral, since the device shaft is located directly in the housing.
Advantages
A sealed pump has the following advantages:
- No leaks when pumping fluid. Even the best seals allow a certain number of leaks. To prevent them from appearing, it is necessary to lubricate the o-rings. To completely eliminate them, you should use a special liquid, which is very expensive. A sealed pump is much easier to maintain and operate.
- Ease of maintenance. The seal on other equipment wears out quickly, so it becomes necessary to repair or replace it. In a sealed pump, the magnetic elements have a long service life, reaching up to 100 years.
Device Properties
These characteristics can not be attributed to either positive or negative sides. Among them are:
- Transmission performance. Previously, pump performance was significantly reduced due to the location of the magnets between the thick walls of the casing. Thanks to modern technologies, its efficiency is 100%.
- Fluid temperature. The hermetic pump is capable of pumping liquid with a temperature of + 200º. When using additional elements, it can increase to + 400º. It all depends on the type of seal.
- Cost. Compared to other models, the price of a sealed element is quite high. It depends on such expensive equipment as magnets, and ranges from 50 thousand to 300 thousand rubles. By the way, in recent years, SPC "Sealed Pumps" has sharply reduced the cost of its products by 40%.
disadvantages
Among the minuses are:
- rapid breakdown of equipment due to the ingress of solid particles;
- the impossibility of idling;
- work only in the set parameters;
- if there are metal elements near the pump, then the demagnetization of the couplings occurs and, as a result, a decrease in performance.
Sealed pump: principle of operation
The principle of operation of sealed equipment is simple.
The pumped liquid enters the pump design through the inlet pipe. Using the rotating wheels, enough is produced to pump fluid from one medium to another. The electric motor and pump are located on the same shaft. The rotor space is filled with water. One part is used as lubricant for bearings. Also, the pumped liquid serves to cool structural elements.
A shielded thin pipe with a sealed cup is installed between the engine and the working medium. The design of the electric motor and rotor provides bearings. In order to make it convenient 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 high performance, so you can quickly pump 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 highlight the high cost of the device. A good sealed pump costs about 200 thousand.
Not everyone can afford this amount. Another disadvantage is the immunity of particulate matter. If the latter gets in, some elements of the pump fail. In order not to spend additional funds on repair or replacement of structural elements, it is necessary to monitor the pumped liquid.
Conclusion
A sealed pump appeared in the late 40s, and since then has been pleasing to many users.
Every year he became better. Therefore, today we have high-quality and useful equipment. As a rule, they are used for pumping aggressive liquids.