It happens that you need 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 and pump shafts are not interconnected. That is why you do not need to make holes in the case. Rotation occurs with the help of magnets attached to the shafts of the pump and motor.
General information
The sealed pump appeared in the world thanks to American scientists in the late 40s.
Until now, pumps have had poor performance. This was due to the fact that the magnets did not touch each other, but were distributed under the case. Due to its large thickness, magnetic losses occurred. Modern technologies can significantly reduce these losses and increase the efficiency of the unit.
Sealed chemical pumps are used for pumping aggressive liquids.
The cost of such equipmentsignificantly 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 resistant metals, it makes no sense to use the pump for pumping ordinary liquids.
Device
As mentioned earlier, there are no holes in the design of the element, which means there will be no leaks.
Looking at the sectional view of the hermetic pump, you can see that it works with the help of two magnets. One of them is located on the pump shaft, and the other is on the motor. Therefore, energy is transferred at a distance. Its rear part is one-piece, as the shaft of the device is located directly in the housing.
Dignity
Sealed pump has the following advantages:
- No leakage when pumping fluid. Even the best seals allow a certain number of leaks to occur. 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. The sealed pump is much easier to maintain and operate.
- Easy maintenance. The seal on other equipment wears out quickly and needs to be repaired or replaced. In a hermetically sealed pump, the magnetic elements have a long service life of up to 100 years.
Device Properties
These characteristics are neither positive nor negativeparties. 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 technology, its efficiency is 100%.
- Liquid temperature. The sealed pump is capable of pumping liquid with a temperature of +200ºС. When using additional elements, it can increase up to +400ºС. 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, the Hermetic Pumps SPC has sharply reduced the cost of its products by 40%.
Flaws
Among the cons are:
- quick breakdown of equipment when solid particles enter;
- inability to idle;
- work only in set parameters;
- if there are metal elements near the pump, then the couplings are demagnetized and, as a result, the performance decreases.
Sealed pump: working principle
The principle of hermetic equipment is simple.
The pumped liquid enters the pump structure through the inlet pipe. With the help of rotating wheels, enough is produced to pump liquid from one medium to another. The motor and pump are on the same shaft. The space of the rotor is filled with water. One part is used as a lubricant for bearings. The pumped liquid also serves to cool the structural elements.
A shielded thin pipe with a sealed glass is installed between the engine and the working medium. Plain bearings are provided in the design of the electric motor and rotor. In order to conveniently monitor their status, 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, thanks to which it is possible to quickly pump liquid from one place to another. A significant advantage is the absence of leaks, as well as a long service life. Among the negative aspects, users highlight the high cost of the device. A good sealed pump costs about 200k
Not everyone can afford such an amount. Another disadvantage is the insensitivity of solid particles. If the latter hit, some elements of the pump fail. In order not to spend additional funds on the repair or replacement of structural elements, it is necessary to monitor the pumped liquid.
Conclusion
The hermetically sealed pump appeared in the late 40s and has delighted many users ever since.
He got better every year. Therefore, today we have high-quality and useful equipment. howas a rule, they are used for pumping aggressive liquids.
