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  • Q Frequently asked questions about water pumps

    A 1. Unable to start
    First, check the power status. If the coupling connection is rigid, the three-phase supply will be different if the fuse blows when the switch contacts are sealed. It may be an open circuit, poor contact, or blown fuse. When encountering such a situation, the cause must be identified and repaired in time. Then check whether it is a mechanical failure of the pump itself.
    Common reasons for the above situation include: the seal is too tight or the impeller and pump body are blocked by debris, the pump shaft, bearings and reduction ring are rusted, the water pump shaft is severely bent, etc.
    Solution: Loosen the packaging and clean the water gutter. Disassemble the pump body and remove dirt and rust. Remove the pump shaft or replace the pump shaft and fix it.
    2. Water pump heats up
    Reasons: The bearing is damaged, the distance between the sub-bearings or brackets is too small, the pump shaft is bent or the two shafts are misaligned, the tape is too tight, the oil volume is insufficient or the oil quality is low. The balance in the impeller is blocked, the impeller is unbalanced, and the impeller thrust is larger to one side.
    Solution: Replace the bearings. Remove the back cover and add a spacer between the bracket and bearing seat. Check the pump shaft or adjust the center of the two shafts. Correctly adjust the tightness of the tape and remove the stopper in the rocker arm hole.
    3. Insufficient traffic
    This is caused by: slow feed due to mismatch or belt slippage. The installation angle of the axial flow pump impeller is too small, the lift is insufficient, the pipeline is too long, or the pipeline is at a right or bent angle, the suction height is too high, the bottom valve, pipelines and impeller are partially blocked or the impeller is damaged. The water supply pipe is leaking badly.
    Solution: Restore normal speed, remove belt grease, and adjust belt tension, adjust impeller angle to reduce pump position, reduce pipe size, or change pipe curvature. Remove obstructions and replace impeller. Replace the leak reduction ring to stop the leak.
    4.Cannot absorb water
    The reason is that the aeration pump and water supply pipe are full of gas, the bottom valve is not completely closed, the water is not completely diverted, the vacuum pump is poorly sealed, and the shutters or flap doors are not completely closed.
    Solution: Press the water first. Then add water to the pump body and start the machine. At the same time, check whether the check valve is closed and there is no air leakage in the pipe or fittings. If there is air leakage after disassembly, use lubricant or paint mixture on the joints and tighten the screws. Check the oil seal ring on the water pump shaft. If it is severely worn, replace it with a new one. There is a water or air leak in the pipe. The nuts may not tighten during installation. If the leakage is not serious, the cement slurry can be mixed with cement oil or asphalt oil instead of air or water leakage. Temporary repairs can be made with a little wet mud or mild soap. If there is leakage at the joint, you can use a wrench to tighten the nut. If the leak is severe, the damaged pipe must be removed and replaced.
  • Q How to properly maintain the magnetic pump?

    A (1) Check whether there is any looseness in the magnetic pump pipeline and joints. Turn the magnetic pump by hand to see if it is flexible.
    (2) Add bearing lubricating oil into the bearing body. Observe that the oil level should be at the center line of the oil mark. The lubricating oil should be replaced or replenished in time.
    (3) Remove the water diversion plug of the magnetic pump body and fill it with water (or slurry).
    (4) Close the gate valve, outlet pressure gauge and inlet vacuum gauge of the water outlet pipe.
    (5) Jog the motor to see if the motor direction is correct.
    (6) Start the motor. When the magnetic pump operates normally, open the outlet pressure gauge and the inlet vacuum pump to see if they show appropriate pressure. Then gradually open the gate valve and check the motor load at the same time.
    (7) Try to control the flow and head of the magnetic pump within the range indicated on the signboard
    (8) During the operation of the magnetic pump, the bearing temperature must not exceed the ambient temperature of 35℃, and the temperature must not exceed 80℃.
    (9) If you find any abnormal sound from the magnetic pump, you should stop the car immediately and check the cause.
    (10) When the magnetic pump is to be stopped, first close the gate valve and pressure gauge, and then stop the motor.
    (11) Within a month of operation of the magnetic pump, change the lubricating oil every 100 hours, and then change the oil every 500 hours.
    (12) Frequently adjust the packing gland to make the leakage in the packing chamber normal (it is better to keep dripping out).
    (13) Regularly check the wear of the shaft sleeve and replace it in time if the wear becomes severe.
    (14) When the magnetic pump is used in cold winter, after stopping, the drain plug at the bottom of the pump body needs to be unscrewed to drain the medium. Prevent frost cracking.
    (15) If the magnetic pump is not used for a long time, it is necessary to disassemble the entire pump, wipe off the water, apply grease to the rotating parts and joints, install them, and keep them properly.
  • Q What is the maintenance method for corrosion-resistant pumps?

    A Corrosion-resistant pumps are widely used in chemical, petroleum, metallurgy, light industry, synthetic fiber, environmental protection, food, pharmaceutical and other industries. Corrosion-resistant pumps have many advantages, including stable performance, easy sealing, easy use and inspection, etc. It plays a great role in improving product quality, and prevents the occurrence of "running, spilling, dripping, leaking" and other phenomena, preventing pollution and fundamentally improving the environment. , then the maintenance of corrosion-resistant pumps What are the methods:
    1. During use, check the operation stability of the corrosion-resistant floor pump unit, observe whether there is abnormal vibration, and pay attention to whether there is abnormal noise. If the cause of the failure is not known, the corrosion-resistant pump operation should be stopped immediately and check. Find out the cause and eliminate it before starting again.
    2. Regularly check and modify the coaxiality of the coupling to prevent deformation, which essentially prevents damage to the corrosion-resistant pump and has certain benefits for production efficiency.
    3. If there is an auxiliary system, the auxiliary system needs to be checked regularly, for example, check the flow and temperature of the cooling system, check the temperature and pressure of the heating system, the pressure, temperature and flow of the seal cleaning system, etc.
    4. When a backup pump is installed, the backup pump should be run regularly. The main purpose is to make the backup pump available for use at any time. When the standby pump has not been used for a long time, the transported liquid must be discharged. It is not as good as cooling water.
    5. When the performance of the corrosion-resistant pump cannot be reduced due to changes in the piping system or changes in the strength of the pipeline, the reduction in pump performance may cause wear of the internal components of the pump. Therefore, the condition of the pump must be checked in time and replaced if necessary. part.
    6. The use and details of the inspection, lubrication and inspection of the corrosion-resistant pump must be recorded in detail, sorted and saved, in order to facilitate better maintenance next time.
  • Q Six precautions for using magnetic pumps

    A 1. Because the cooling and lubrication of the steel magnetic pump bearings depend on the transported medium, it is prohibited to run without load, and at the same time, avoid running without load caused by restarting after a power outage during work.
    2. If the transported medium contains solid particles, a filter must be installed at the pump inlet: if it contains ferromagnetic particles, a magnetic filter must be installed.
    3. When the pump is in use, the ambient temperature should be less than 40°C, and the motor temperature rise should not exceed 75°C.
    4. The transported medium and its temperature should be within the allowable range of the pump material. The operating temperature of engineering plastic pumps is <100°C, the operating temperature of metal pumps is <100°C, the delivery and suction pressure is not greater than 0.2MPa, the maximum working pressure is 1.6MPa, the density is not greater than 1600Kg/m3, and the viscosity is not greater than 30X10-6m2/S. Liquid containing hard particles and fibers.
    5. If the conveying liquid is a medium that is prone to precipitation and crystallization, it should be cleaned in time after use to drain the accumulated liquid in the pump.
    6. After the magnetic pump has been operating normally for 1,000 hours, the bearings and end face moving rings should be disassembled and inspected for wear, and consumable parts that should not be reused should be replaced.
  • Q Should viscosity be considered when selecting a magnetic pump?

    A The viscosity should be considered when selecting a magnetic pump! During the selection process, the magnetic pump should be selected based on the nature of the company's production equipment, its own conditions and permitted conditions. It is mainly considered from the aspects of medium transportation volume, device lift, medium properties, pipeline layout and operating conditions.
    1. Select according to the physical and chemical properties of the delivery medium
    The physical and chemical properties of the conveyed medium directly affect the performance, material and structure of the pump and are one of the important factors to be considered when selecting the pump.
    The physical and chemical properties of the medium include: medium name, medium characteristics (such as corrosiveness, abrasiveness, toxicity, etc.), solid particle content and particle size, density, viscosity, vaporization pressure, etc. If necessary, the gas content in the medium should also be listed, indicating whether the medium is easy to crystallize, etc.
    2. Select according to process parameters
    Process parameters are an important basis for magnetic pump cleaning and should be determined based on the process flow and operating change range values. For example, flow rate and head are one of the important process parameters for pump selection, which are directly related to the production capacity and transportation capacity of the entire device.
    (1) Quantity Q
    Flow refers to the amount of medium required to be transported by the pump during the production of process equipment.
    Pump data sheets often only give normal flow and rated flow. When selecting a magnetic pump, the rated flow rate is required to be 1.1 to 1.15 times the normal flow rate.
    (2) Lift H
    The value of the lift required by the process device is also called the calculated lift. Generally, the rated lift of the pump is required to be 1.05~1.1 times the required lift of the device.
    (3) Inlet pressure and outlet pressure
    The inlet and outlet pressures refer to the pressure at the pump inlet and outlet flanges. The magnitude of the inlet and outlet pressures affects the pressure resistance requirements of the shell and shaft seal (isolation sleeve).
    Refers to the inlet medium temperature of the pump
    (5) Device cavitation allowance NPSHa
    Also called effective NPSH
    (6)Operating status
    The operating status is divided into two types: continuous operation and intermittent operation.
    3. Select the magnetic pump according to the site conditions.
    Magnetic pump site conditions include:
    (1) Installation location (indoor, outdoor, plateau, seaside);
    (2) Ambient temperature:
    (3) Relative humidity:
    (4) Atmospheric pressure:
    (5) Atmospheric corrosion conditions:
    (6) Classification of hazardous areas
    4. Select according to the pipeline layout conditions of the system
    The pipeline layout conditions of the system refer to some data such as the height, distance and direction of the transported liquid, as well as pipeline specifications and their length, materials, pipe fitting specifications, quantity, etc., in order to calculate the system lift and check the steam margin.
    5. Select according to operating conditions
    There are many contents of operating conditions, such as gun and steam pressure, suction side pressure, discharge side container pressure, altitude, ambient temperature, whether the operation is intermittent or continuous, and whether the position is fixed or adjustable in the operation of the medium (liquid). Mobile etc.
  • Q What are the misunderstandings in using fluorine-lined pipeline pumps?

    A What are the misunderstandings in using fluorine-lined pipeline pumps?
    Fluorine-lined pipeline pumps are mainly used to transport various corrosive media (such as acids, alkalis, salts, etc.) and are suitable for petroleum, chemical and electronic industries. When transporting media containing solid particles and high viscosity, wear-resistant pumps should be used. Type fluorine lined pipeline pump. It is characterized by excellent corrosion resistance, long service life, balanced operation and low noise.
    The following misunderstandings are easy to occur when using fluorine-lined pipeline pumps:
    1. High-lift pumps use low-lift pumps to pump water. Some customers who use village cyanide pipeline pumps feel that the lower the pumping head, the smaller the motor load. Due to this misunderstanding, when purchasing a cyanide-lined pipeline pump, most people will choose a higher pump head. In fact, the first glance determines the type of pump, and the power consumption is proportional to the actual flow rate of the pump. Since the flow rate of the pump decreases with the head, the higher the head, the smaller the flow rate and the smaller the power consumption: On the contrary, the greater the flow rate, the greater the power consumption. Therefore, in order to prevent motor overload, it is generally required that the actual pumping head of the pump is not less than 60% of the calibrated head.
    2. When installing the water supply pipeline, the horizontal section will be horizontal or warped upward. In this way, air gathers in the water supply pipe, the vacuum degree of the water pipe and village oxygen pipe pump is reduced, and the water suction head of the pump is reduced, which will lead to a reduction in water output. The correct way is to tilt the horizontal section slightly towards the direction of the water source. It cannot be horizontal, let alone upward. warping.
    3. The water inlet of the liner pump is directly connected to the elbow. This will cause uneven distribution of water flow into the impeller through the elbow. When the diameter of the water supply pipe is larger than the pump inlet, please install an eccentric throttle. The flat parts of the eccentric tube should be installed on the upper surface, and the inclined parts should be installed on the lower surface. Otherwise, collect air, reduce water or pump, and make a pounding sound.
    4. The water level at the outlet of the outlet is higher than the normal water level of the outlet pool. In this case, the pump flow rate will be reduced. When the outlet must be higher than the outlet level under terrain conditions, the outlet should be installed with a time pipe and a short pipe. The water pipe is in the form of a siphon to reduce the water outlet height.
          5. When installing the bottom valve, the end of the water supply pipe is not vertical. After installation, the valve cannot close by itself, which will cause water leakage. The correct installation method is that the end should be vertical. When the water pipe cannot be installed vertically under terrain conditions, the water pipe The angle between the axis and the horizontal plane must be more than 60%.
  • Q What will happen if the installation height of the centrifugal pump is too high?

    A Centrifugal pump is a common industrial pump widely used in various fields, such as chemical industry, petroleum, metallurgy, electric power, etc. When installing a centrifugal pump, you need to pay attention to many details. One of the important issues is the installation height of the centrifugal pump. Normally, the installation height of the centrifugal pump should not be too high, otherwise it will affect the normal operation of the centrifugal pump. So, why should the centrifugal pump not be installed too high from the ground? This article will analyze and discuss it from multiple aspects.
    Why should you not install a centrifugal pump too high from the ground?
    First, the installation height of the centrifugal pump is too high, which will increase the suction resistance of the pump. When the installation height of the centrifugal pump is too high, the length of the pump's suction pipe will also increase accordingly, thereby increasing the pump's suction resistance. If the suction resistance is too large, the suction volume of the pump will be insufficient, thus affecting the normal operation of the pump. Therefore, in order to ensure the normal suction of the pump, the installation height of the centrifugal pump should not exceed a certain range.
    Secondly, if the installation height of the centrifugal pump is too high, it will also increase the outlet pressure of the pump. When the installation height of a centrifugal pump is too high, the length of the outlet pipe of the pump will also increase accordingly, thereby increasing the outlet pressure of the pump. If the outlet pressure is too high, the flow rate of the pump will be reduced, thus affecting the normal operation of the pump. Therefore, in order to ensure the normal outlet of the pump, the installation height of the centrifugal pump should not exceed a certain range.
    Third, the installation height of the centrifugal pump is too high and it will increase the vibration and noise of the pump. When the installation height of a centrifugal pump is too high, the center of gravity of the pump will increase accordingly, thereby increasing the vibration and noise of the pump. If the vibration and noise are too large, it will affect the normal operation of the pump and even cause equipment failure. Therefore, in order to ensure the normal operation of the pump, the installation height of the centrifugal pump should not exceed a certain range.
    To sum up, if the installation height of the centrifugal pump is too high, it will affect the normal operation of the pump, mainly by increasing the suction resistance, outlet pressure, vibration and noise of the pump. Therefore, when installing a centrifugal pump, attention needs to be paid to controlling the installation height of the centrifugal pump to ensure the normal operation of the pump. At the same time, regular inspection and maintenance of the centrifugal pump is also required to extend the service life of the centrifugal pump. 



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