Acid and alkali resistant anticorrosive pump motor loss is too high how to do?

　　Acid and alkali corrosion-resistant pumps are commonly used in industrial production of water pumps, acid and alkali resistance of the particularity of the importance of corrosion resistance, users usually choose good corrosion resistance, corrosion resistance of the full range of corrosion-resistant pumps, usually corrosion-resistant pumps have fluorine plastic corrosion-resistant pumps, stainless steel corrosion-resistant pumps, corrosion-resistant pumps, anticorrosive wear pumps, etc., corrosion-resistant pumps are usually used in the form of an electric motor, due to the different media conveyed, the high motor loss how to do, the motor in the conversion of electrical energy into mechanical energy at the same time, itself also lose a portion of energy. Converted to mechanical energy at the same time, itself also lose part of the energy, motor loss can be generally divided into variable loss, fixed loss and stray loss of three parts.

　　1, variable loss is changed with the load, including stator resistance loss (copper loss), rotor resistance loss and brush resistance loss.

　　2, fixed loss has nothing to do with the load, including iron core loss and mechanical loss. Iron loss is composed of hysteresis loss and eddy current loss, which is proportional to the square of the voltage, of which the hysteresis loss is also inversely proportional to the frequency.

　　3, other stray losses are mechanical losses and other losses, including bearing friction losses and fans, rotors, etc. due to the rotation of the wind resistance losses.

　　Several measures to reduce motor losses

　　First, a certain stator loss: the main methods to reduce motor stator I^2R loss are:

　　1, increase the stator slot cross-sectional area, in the case of the same stator outer diameter, increase the stator slot cross-sectional area will reduce the magnetic circuit area, increase the magnetic density of the teeth.

　　2, increase the full slot rate of the stator slot, which is more effective for low-voltage small motors, the application of the best winding and insulation size, large wire cross-section area can increase the full slot rate of the stator.

　　3, try to shorten the length of the stator winding end, stator winding end loss accounts for the total loss of winding 1/4 ~ 1/2, reduce the length of the winding end, can improve motor efficiency. Experiments show that the length of the end of the degree of reduction of 20%, the loss decreased by 10%.

　　Second, stray loss; today's understanding of motor stray loss is still in the research stage, now some of the main methods to reduce stray loss are:

　　1, the use of heat treatment and finishing to reduce the rotor surface short circuit.

　　2、Insulation treatment of rotor slot inner surface.

　　3、Reduce harmonics by improving the stator winding design.

　　4, improve the rotor slot with the design and coordination to reduce harmonics, increase the stator, rotor teeth groove, the rotor slot shape designed as a slant slot, the use of series connected sinusoidal windings, scattered windings and short-pitch windings can greatly reduce the high harmonics; the use of magnetic slots or magnetic slot wedge to replace the traditional insulation slot wedge, magnetic slot mud to fill the slot of the stator core of the motor is to reduce the additional spurious losses of an effective method.

　　Third, the wind and friction losses; wind and friction losses account for about 25% of the total motor losses, should be due attention. Friction loss is mainly caused by bearings and seals, can be reduced by the following measures:

　　1, minimize the size of the shaft, but need to meet the requirements of the output torque and rotor dynamics.

　　2、Use of high-efficiency bearings.

　　3、Use high efficiency lubrication system and lubricant.

　　4/ Use advanced sealing technology.

　　Fourth, rotor loss: motor rotor I^2R loss is mainly related to the rotor current and rotor resistance, the corresponding energy-saving methods are mainly:

　　1, reduce the rotor current, which can be considered from improving the voltage and motor power factor.

　　2, increase the rotor slot cross-sectional area.

　　3, reduce the resistance of the rotor winding, such as the use of thick wire and low resistance materials, which is more meaningful for small motors, because small motors are generally cast aluminum rotor, if the use of cast copper rotor, the total loss of the motor can be reduced by 10% to 15%, but today's cast copper rotor required to manufacture the temperature is high and the technology has not yet been popularized, and its cost is higher than that of the cast aluminum rotor 15% to 20%.

　　Fifth, iron core loss; motor iron consumption can be reduced by the following measures:

　　1, reduce the magnetic density, increase the length of the iron core to reduce the magnetic flux density, but the amount of iron used in the motor increases.

　　2, reduce the thickness of the iron chip to reduce the loss of induced current, such as cold rolled silicon steel instead of hot rolled silicon steel can reduce the thickness of silicon steel, but the thin iron chip will increase the number of iron chips and motor manufacturing costs.

　　3, the use of cold rolled silicon steel sheet with good magnetic conductivity to reduce hysteresis loss.

　　4, the use of high-performance iron chip insulation coating.

　　5, heat treatment and manufacturing technology, iron chip processing after the residual stress will seriously affect the motor loss, silicon steel sheet processing, cutting direction, punching and shearing stress on the iron core loss. Along with the milling direction of the silicon steel sheet cutting, and heat treatment of silicon steel punching, can reduce the loss of 10% to 20% and other methods to achieve.