Basic structure of centrifugal pump
What parts constitute the centrifugal pump?
Centrifugal pumps are widely used in the production of the chemical industry. This is due to their wide performance range (including flow rate, pressure head, and discomfort to the nature of the medium), small size, simple structure, easy operation, uniform flow rate, and confusion. Outstanding advantages such as less, long life, lower purchase and operating costs. It refers to a pump that conveys liquid by the centrifugal force generated when the impeller rotates. The centrifugal pump is composed of many parts. The basic structure of the centrifugal pump is mainly composed of the pump casing, pump shaft, bearing, impeller, sealing ring, etc
Part of the structure, as shown below:
The pump body of the centrifugal pump is also called pump casing, which is the main body of the water pump. It plays a supporting and fixing role and is connected with the bracket on which the bearing is installed. The pump casing has two types: axial split type and radial split type. The shells of most single-stage centrifugal pumps are of volute type, and the multi-stage pump's radial split casing is generally an annular casing or a circular casing. The inner cavity of the general volute type pump casing is a spiral flow channel, used to collect the liquid flowing out of the impeller, and lead it to the diffusion pipe to the pump outlet. The bearing capacity of the pump casing is subject to the full working pressure and the thermal load of the liquid.
The function of the pump shaft of the centrifugal pump is to connect the motor with the coupling and transmit the torque of the motor to the impeller, so it is the main component to transmit mechanical energy. The pump shaft is fixed with an impeller at one end and a coupling at one end. According to the size of the pump, rolling bearings and sliding bearings can be selected as bearings.
The plain bearing uses transparent oil as lubricant, add oil to the oil level line. Too much oil must seep along the pump shaft, too little bearing and overheating and burnout will cause an accident! During the operation of the pump, the temperature of the bearing is up to 85 degrees, and generally runs at about 60 degrees.
The impeller is the core part of the centrifugal pump. Its speed is higher and the force is higher. The blades on the impeller play a main role. The impeller must pass the static balance experiment before assembly. The inner and outer surfaces of the impeller are required to be smooth to reduce the frictional loss of water flow. The pump does work on the liquid through the impeller. There are three types of impellers: closed, open and semi-open. Road closed impeller is composed of blade, front cover and rear cover. The semi-open impeller consists of blades and a back cover. The open impeller has only blades and no front and rear covers. Closed impellers have higher efficiency, and open impellers have lower efficiency.
The sealing ring is also called the leakage reduction ring. The function of the sealing ring of the centrifugal pump is to prevent the internal and external leakage of the pump. The sealing ring made of wear-resistant material is embedded on the front and back cover electrodes of the impeller and the pump casing. It can be replaced after being worn.
The stuffing box is mainly composed of packing, water sealing ring, packing cylinder, packing gland, and water sealing tube. The purpose of the stuffing box is mainly to close the gap between the pump casing and the pump shaft, so that the water flow in the pump does not flow outside and the outside air does not enter the pump. Always keep the vacuum inside the pump! When the friction between the pump shaft and the packing generates heat, it is necessary to rely on the water seal tube to hold the water into 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 tour inspection of the pump operation! The filler should be replaced after about 600 hours of operation.
The working principle of the centrifugal pump is to use the rotation of the impeller to make the water centrifugal move to work. Before starting the pump, the pump casing and the suction pipe must be filled with water, and then the motor is started, so that the pump shaft drives the impeller and water to perform high-speed rotational movement. The water undergoes centrifugal motion and is thrown toward the outer edge of the impeller. The channel flows into the pressurized water pipeline of the pump.
