The basic structure of the 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 rotational speed and the blade on the impeller plays a major role. The impeller must pass the static balance test before assembly. The inner and outer surfaces of the impeller are required to be smooth to reduce the frictional loss of water flow.
2, the pump body is also called the pump casing, it is the main body of the pump. It acts as a support and is attached to the bracket on which the bearing is mounted.
3. The function of the pump shaft is to connect the coupling to the motor and transfer the torque of the motor to the impeller, so it is the main component that transmits mechanical energy.
4. The bearing is a member that supports the pump shaft on the pump shaft, and has two kinds of rolling bearings and sliding bearings. Rolling bearings use butter as a lubricant to refuel properly. Generally 2/3~3/4 of the volume will heat too much, too little and there will be noise and heat! The sliding bearing uses transparent oil as the lubricant, refueling to the oil level line. Too much oil will ooze along the pump shaft and float. Too few bearings will overheat and burn out. The temperature of the bearing is up to 85 degrees during the operation of the pump. Generally, it is about 60 degrees. If it is high, it is necessary to find the cause. (Is there any impurities, whether the oil is black, whether it is water) and timely treatment.
5, the seal ring is also called the leak ring. The gap between the impeller inlet and the pump casing is too large, so that the water in the high pressure zone of the pump flows to the low pressure zone through the gap, which affects the water output of the pump and reduces the efficiency. If the clearance is too small, the friction between the impeller and the pump casing may cause friction. In order to increase the backflow resistance and reduce the internal leakage, and delay the service life of the impeller and the pump casing, a sealing ring is arranged at the inner edge of the pump casing and the outer joint of the impeller, and the sealing gap is preferably maintained between 0.25 and 1.10 mm.
6. The stuffing box is mainly composed of packing, water sealing ring, packing tube, packing gland and water sealing tube. The function of the stuffing box is mainly to close the gap between the pump casing and the pump shaft, so that the water in the pump does not flow to the outside and the outside air does not enter the pump. Always keep the vacuum inside the pump! When the pump shaft and the packing friction generate heat, the water should be sealed to the water seal ring to cool the packing. Keep the pump running normally. Therefore, it is especially important to check the stuffing box during the running inspection of the pump! The packing should be replaced after about 600 hours of operation.
