What is the difference between a shielded pump and a magnetic pump and a centrifugal pump?
The fully sealed, or leak-free, construction of the shielded pump makes it ideal for pumping flammable, expensive, corrosive and toxic liquids. Because the shield pump does not leak, it contributes to the safety of the flammable liquid system; it has outstanding economic effects for valuable and corrosive liquids.
Different points of the shield pump
1. The integrated structure of the motor and the water pump, the water pump and the motor are coaxially connected;
2. There is a shielding sleeve on the inner side of the stator and the outer side of the rotor, and the inner side of the shielding sleeve is connected with the inside of the pump;
3, the installation method is divided into horizontal and vertical
4. The motor cancels the cooling fan, and the motor is cooled by the circulating medium between the stator and the rotor, and the surface of the motor base is cooled.
Shield pump advantages
1, fully enclosed. There is no dynamic seal on the structure, only static seal at the outer shell of the pump, so it can be completely leak-free, especially suitable for conveying flammable, explosive, valuable liquids and toxic, corrosive and radioactive liquids.
2. High security. The rotor and the stator each have a shielding sleeve so that the rotor and the stator of the motor are not in contact with the material, and even if the shielding sleeve is broken, there is no danger of external leakage.
3. The structure is compact and covers a small area. The pump and the motor are integrated, and there is no need to find the center. Low requirements on the base and foundation, and less daily maintenance work and low maintenance costs.
4, smooth operation, low noise, no need to add lubricant. Since there is no rolling bearing and motor fan, no lubrication is required and the noise is low.
5, a wide range of uses. It can meet the requirements of various working conditions such as high temperature, high pressure, low temperature and high melting point.
Shortcomings of shielded pumps
1. Since the shield pump adopts a sliding bearing and is lubricated by the medium to be transported, the medium with poor lubricity should not be transported by a shield pump. Generally suitable for shielding the pump medium has a viscosity of 0.1 to 20 mPa.s.
2. The efficiency of the shield pump is usually lower than that of the single-end mechanical seal centrifugal pump, which is roughly equivalent to the double-end mechanical seal centrifugal pump.
3. Operating under small flow conditions for a long time, the efficiency of the shielding pump is low, which will cause heat and evaporation of the liquid, which will cause the pump to dry and dry, thus damaging the sliding bearing.
Shield pump use occasion
1. When the pressure condition is not normal. It is used when the pressure on the suction side of the pump is high and the difference between the pressure on the discharge side is small. If the stuffing box is used, it will bear additional stress.
2. It is necessary to maintain a high vacuum. If a stuffing box is used, air will enter through the stuffing box when the shaft is slightly eccentric or worn.
3. When the vacuum and pressure are alternately operated. Stuffing boxes or sealing structures for normal vacuum operation cannot be used for operation under pressure.
4. Where to handle expensive liquids. Liquid, causing greater economic losses.
5. Where to deal with toxic liquids. And the harm of life. If a stuffing box is used, the loss of a considerable amount of valuable each year due to leakage, such as the use of stuffing boxes, leakage of toxic liquids, will cause human health,
6. Occasional explosive gas. Although flammable liquids such as gasoline, kerosene, jet fuel, etc. can be transported by a centrifugal pump with a rotary seal connected to an explosion-proof motor, the leaking liquid and the vapor-forming liquid will make the entire site an explosion hazard. The place.
7. Where there is a radioactive liquid. It is not allowed to leak from the stuffing box with a radioactive liquid. In addition, many filler materials are not compatible with long-term contact with radioactive liquids.
8. Where corrosive liquids are handled. In addition to localized corrosion due to leakage of the stuffing box, the process unit is also eroded by steam generated by corrosive liquid leakage.
9. Where to deal with harmful liquids. When a harmful gas such as malodor is generated due to leakage of the stuffing box, a bad condition in which operation cannot be performed is formed.
10. Handle easy to react liquids. If a shielded pump is used, the liquid will not be contaminated by anger, moisture, filler lubricant and other substances, nor will it crystallize and cause other obstacles.