The basic structure of the self-priming centrifugal pump
The basic structure of a self-priming centrifugal pump is composed of six parts: impeller, pump body, pump shaft, bearing, sealing ring, and stuffing box.
1. The impeller is the core part of the self-priming centrifugal pump. It has a high speed and a large output. The blades on the impeller play a major role. The impeller must pass a static balance experiment before assembly. The inner and outer surfaces of the impeller are required to be smooth to reduce the friction loss of the water flow.
2. The pump body is also called the pump housing, which is the main body of the pump. Play a supporting and fixing role, and connect with the bracket for mounting the bearing.
3. The function of the pump shaft is to connect the motor with the coupling, and transmit the torque of the motor to the impeller, so it is the main component for transferring mechanical energy.
4. The bearing is a component that is sleeved on the pump shaft to support the pump shaft. There are two types of rolling bearings and sliding bearings. Rolling bearings use tallow as a lubricant and refuel appropriately. Generally, 2/3～3/4 of the volume is too much to generate heat, too little and there is noise and heat! Sliding bearings use transparent oil as lubricant, add oil to the oil level line. Too much oil will seep out along the pump shaft and drift low, too little bearings will overheat and burn out and cause accidents! During the operation of the pump, the temperature of the bearings will be as high as 85 degrees and generally run around 60 degrees. If it is high, find the cause (Whether there are impurities, whether the oil is black, whether water has entered) and deal with it in time.
5. The sealing ring is also called the leakage reducing ring. If the gap between the impeller inlet and the pump casing is too large, the water in the high-pressure area of the pump flows to the low-pressure area through this gap, which affects the pump's water output and reduces efficiency! Too small a gap will cause friction and wear between the impeller and the pump casing. In order to increase the reflux resistance, reduce internal leakage, and delay the service life of the impeller and the pump casing, a sealing ring is installed at the junction of the inner edge of the pump casing and the external aid of the impeller, and the sealing gap should be kept between 0.25 and 1.10 mm.
6. The stuffing box is mainly composed of packing, water seal ring, packing tube, packing gland and water seal pipe. The function of the stuffing box is mainly to close the gap between the pump casing and the pump shaft, and prevent the water flow in the pump from flowing outside and the outside air from entering the pump. Always maintain the vacuum in the pump! When the pump shaft and the packing friction generate heat, the water seal pipes the water to the water seal ring to cool the packing. Keep the pump running normally. Therefore, special attention should be paid to the inspection of the stuffing box during the running inspection of the pump! The stuffing should be replaced after 600 hours of operation.
