First, the pump is not the cause of the water analysis Into the water pipe and the pump body air (1) before the pump is not fully filled with water, it seems that irrigation has overflowed from the vent hole, but did not turn the pump shaft air completely discharged, resulting in a little residual air Inlet or pump body. (2) In case of contact with the water pump, the horizontal section of the water inlet pipe should be descended 0.5% or more to the reverse water flow direction. Up tilt, the intake pipe will remain in the air, reducing the vacuum hose and pump, affecting water absorption. (3) The long-term use of the pump packing has been worn or the packing pressure is too loose. As a result, a large amount of water is ejected from the gap between the packing and the pump shaft sleeve. As a result, external air enters the pump from these gaps and affects the water supply. (4) The water inlet pipe is corroded due to long-term submergence, and the surface of the water pump is continuously declining. When the water holes are exposed, the air enters the water pipe from the water hole. (5) cracks in the inlet pipe cracks, inlet pipe and pump connections appear a small gap, are likely to make the air into the inlet pipe. Second, the pump speed is low (1) human factors. Some users due to the original motor damage, it is coupled with another motor-driven, resulting in a small flow, head low water consequences. (2) the pump itself mechanical failure. Impeller and pump shaft nut loose or deformation of the pump shaft bending, causing the impeller to move more, directly with the pump body friction, or bearing damage, are likely to reduce the pump speed. (3) power machine repair is not working. The motor burned due to the winding, and loss of magnetism, the maintenance of winding turns, diameter, wiring methods change, or maintenance failure is not completely ruled out factors will also make the pump speed change. Third, the pump suction too deep Some of the water is deep, some water peripheral potential is relatively flat, while ignoring the pump allowable suction, resulting in little or no water absorption results. To know the pump suction port to establish a degree of vacuum is limited, the absolute vacuum suction is about 10 meters high water column, and the pump can not establish an absolute vacuum. The degree of vacuum is too large, easy to gasify the pump, work on the pump negative. Each centrifugal pump has its maximum allowable suction, usually between 3-8.5 meters. Do not install the pump only easy and simple. Fourth, the water flow into the water pipe resistance loss is too large Some users measure the reservoir or water tower to the water surface vertical distance slightly less than the pump head, but to mention a small amount of water or mention the water. The reason is often too long pipe, pipe bend more water pipe resistance loss is too large. The reason is often too long pipe, pipe bend more water pipe resistance loss is too large. Under normal circumstances, 90-degree elbow bend than the 120-degree bend resistance, each 90-degree elbow head loss of about 0.5-1 meters, 20 meters of pipe resistance can make head loss of about 1 meter. In addition, some users are also free to pump into and out of pipe diameter, these have some impact on the lift. Fifth, other factors (1) at the end of the valve can not be opened. Pump is usually set aside too long time, the bottom valve gasket was sticky, no gasket at the end of the valve may rust. (2) the bottom valve filter is clogged; or the bottom valve causes the clogging of the filter in the sludge layer. (3) impeller wear serious. Impeller blades worn by long-term use, affecting the pump performance. (4) the valve can be a check valve faulty or blocked will result in reduced flow pumping pumping. (5) Leakage in the outlet pipe will also affect the amount of water delivered. Sixth, commonly used simple equipment fault diagnosis methods commonly used simple state monitoring methods are auscultation method, touch method and observation method. 1, auscultation method equipment normal operation, accompanied by the sound always has a certain temperament and rhythm. Familiar with and master these normal temperament and rhythm, the human hearing function can compare the equipment whether there is heavy, miscellaneous, strange, chaotic noise, to determine the internal loosening equipment, impact, imbalance and other hidden dangers. Tap the parts with a hand hammer, listen to the occurrence of cracked noise, can determine whether there is a crack. Electronic stethoscope is a vibration acceleration sensor. It converts equipment vibrations into electrical signals and amplifies them, and workers use headphones to listen to vibrations of operating equipment to enable qualitative measurements of the sound. Measuring the same measuring point, at different times, the same speed, the same conditions under the signal, and compared to determine whether the equipment failure. When the headset appears crisp and sharp noise, indicating a higher vibration frequency, the general size is relatively small, relatively high strength parts of the local defects or tiny cracks. When the headset came out of the turbid low noise, indicating that the vibration frequency is low, the general size is relatively large, relatively low strength parts larger cracks or defects. When the headphone noise increases than usual, indicating that the fault is developing, the greater the sound, the more serious the fault. When the noise comes out of the headset is intermittent irregular clutter, indicating a loose parts or components. 2, touch method touch with the manpower can monitor equipment temperature, vibration and gap changes. Nerve fibers on the human hand is more sensitive to temperature, you can more accurately distinguish the temperature within 80 ℃. When the temperature of the machine is about 0 ℃, feel cold, if the touch for a long time will produce biting pain. About 10 ℃, feel cooler, but generally tolerate. 20 ℃ or so, feel cooler, longer contact time, feel warm gradually. About 30 ℃, feel warm, comfortable. 40 ℃ or so, feel hot, slightly hot feeling. About 50 ℃, feel hot, if the palm according to time longer, there will be sweat. 60 ℃ or so, feel very hot, but generally can withstand 10s long time. About 70 ℃, the feeling of burning pain, the general can only endure 3s for a long time, the hand touch will quickly turn red. When touched, touch it and touch it carefully to estimate the temperature rise of the part. Rocking the workpiece by hand can feel the 0.1mm-0.3mm gap size. Touching the parts by hand can feel the vibration intensity changes and whether the impact, as well as the slide board crawling situation. With a surface thermocouple probe thermometer measuring rolling bearings, sliding bearings, spindle boxes, motors and other parts of the surface temperature, it has to determine the thermal anomalies.