Working principle and precautions of stainless steel magnetic pump products
The stainless steel magnetic drive pump consists of three parts: pump, magnetic actuator and electric motor. The key component magnetic actuator consists of external magnetic rotor, inner magnetic rotor and non-magnetic isolation sleeve.
Stainless steel "target=_blank> stainless steel magnetic drive pump consists of three parts: pump, magnetic actuator and electric motor. The key component magnetic actuator consists of external magnetic rotor, inner magnetic rotor and non-magnetic isolation sleeve. When the motor drives the external magnetic rotor When rotating, the magnetic field can penetrate the air gap and the non-magnetic material, and the inner magnetic rotor connected to the impeller can be synchronously rotated to realize the non-contact transmission of the power, and the dynamic seal is converted into a static seal. Since the pump shaft and the inner magnetic rotor are pumped The isolation sleeve is completely enclosed, thus completely solving the safety hazard of the flammable, explosive, toxic and harmful medium leaking through the pump seal in the refining and chemical industry, which effectively guarantees the physical and mental health and safe production of the employees.
First, stainless steel "target=_blank> stainless steel magnetic pump working principle
The n pairs of magnets (n is an even number) are regularly arranged on the inner and outer magnetic rotors of the magnetic actuator, so that the magnet parts form a complete magnetic system. When the inner and outer magnetic poles are opposite poles, that is, two The displacement angle Φ=0 between the magnetic poles, the magnetic energy of the magnetic system is the lowest at this time; when the magnetic pole rotates to the same pole, that is, the displacement angle between the two magnetic poles is Φ=2π/n, the magnetic energy of the magnetic system is the largest. The external force is removed. After that, since the magnetic poles of the magnetic system repel each other, the magnetic force will restore the magnet to the state with the lowest magnetic energy. Then the magnet generates motion to drive the magnetic rotor to rotate.
Second, stainless steel "target=_blank> stainless steel magnetic pump structure features
1. Permanent magnets Permanent magnets made of rare earth permanent magnets have a wide operating temperature range (-45-400 °C), high coercivity, and good anisotropy in the direction of the magnetic field. Demagnetization occurs and is a good source of magnetic field.
2. When the isolation sleeve is in the metal isolation sleeve, the isolation sleeve is in a sinusoidal alternating magnetic field, and the eddy current is induced and converted into heat in the section perpendicular to the magnetic field line. The expression of the eddy current is: where the Pe- eddy current , K—constant, n—the rated speed of the pump, the T-magnetic drive torque, the pressure in the F-sleeve, the inner diameter of the D-slit sleeve, the resistivity of a material, the tensile strength of the material. When the pump is designed n, T is given by the working conditions, to reduce the eddy current can only be considered from the aspects of F, D, etc. The use of high resistivity, high strength non-metallic materials to make the isolation sleeve, the effect is very obvious in reducing the eddy current.
3. Control of the flow rate of the cooling lubricant When the pump is running, the air gap between the inner magnetic rotor and the spacer sleeve and the friction pair of the sliding bearing must be flushed with a small amount of liquid. The flow rate of the coolant is usually the pump design flow. 2%-3%, the annulus region between the inner magnetic rotor and the isolating sleeve generates high heat due to eddy current. When the cooling lubricating fluid is insufficient or the flushing hole is not smooth and blocked, the medium temperature is higher than the working temperature of the permanent magnet. The internal magnetic rotor is gradually lost magnetic and the magnetic actuator is disabled. When the medium is water or water-based liquid, the temperature rise of the annulus region can be maintained at 3-5 ° C; when the medium is hydrocarbon or oil, The temperature rise in the annulus region is maintained at 5-8 °C.
4, sliding bearing magnetic drive pump sliding bearing materials are impregnated graphite, filled with polytetrafluoroethylene, engineering ceramics, etc.. Because engineering ceramics have good heat, corrosion and friction resistance, so the magnetic bearing sliding bearings are mostly used Engineering ceramics production. Because the engineering ceramics are very brittle and the expansion coefficient is small, the bearing clearance should not be too small, so as to avoid the occurrence of the axle accident.
Since the sliding bearing of the magnetic pump is lubricated by the medium to be conveyed, the bearing should be made of different materials according to different media and working conditions.
5. Protection measures When the driven component of the magnetic actuator runs under overload or the rotor is stuck, the main and driven components of the magnetic actuator will automatically slip off and protect the pump. At this time, the permanent magnet on the magnetic actuator is at Under the action of the alternating magnetic field of the active rotor, eddy loss and magnetic loss will occur, causing the temperature of the permanent magnet to rise and the magnetic actuator to slip off.
Third, the advantages of stainless steel "target=_blank> stainless steel magnetic drive pump
Compared with centrifugal pumps that use mechanical seals or packing seals, magnetic pumps have the following advantages.
1. The pump shaft is changed into a closed static seal by the dynamic seal, completely avoiding the medium leakage.
2. No need for independent lubrication and cooling water to reduce energy consumption.
3, from the coupling drive to synchronous drag there is no contact and friction. Power consumption is small, high efficiency and damping damping effect, reducing the impact of motor vibration on the pump and the impact of the cavitation vibration of the pump on the motor .
4. When the internal and external magnetic rotors are slipped off during overload, they have a protective effect on the motor and pump.
Fourth, stainless steel "target=_blank> stainless steel magnetic pump operation precautions
1. Prevent particles from entering (1) Do not allow ferromagnetic impurities, particles enter the magnetic actuator and bearing friction pair (2) After transporting the medium that is easy to crystallize or precipitate, flush it in time (after pumping, pump the water to the pump chamber for 1 min) After the discharge is clean), to ensure the service life of the sliding bearing. (3) When conveying the medium containing solid particles should be filtered at the inlet of the pump tube.
2, to prevent demagnetization (1) magnetic torque can not be designed too small (2) should be operated under the specified temperature conditions, the medium temperature is not exceeded. A magnetic resistance pump can be installed on the outer surface of the isolation sleeve to detect the temperature of the annulus region. l, so that the alarm or shutdown when the temperature exceeds the limit.
3, to prevent dry friction (1) is strictly prohibited to idling (2) prohibiting the medium to evacuate (3) in the case of the outlet valve is closed, the pump continuous running time should not exceed 2min to prevent the magnetic actuator from overheating and fail. Article from: http:// NewsDetail234T2.htmlChina Hardware Business Network http://news.chinawj.com.cn Editor: (Hardware Business Network Information Center) http://news.chinawj.com.cn
Fuonce Lighting , https://www.fuonce.com