The difference between submersible pumps and centrifugal pumps

Submersible pump

A very versatile water treatment tool. The difference from ordinary pumps is that they work underwater, while pumps mostly work on the ground. The working principle of the submersible pump Before starting the pump, the suction pipe and the pump must be filled with liquid. After the pump is turned on, the impeller rotates at a high speed, and the liquid in it rotates with the blades. Under the action of centrifugal force, it flies away from the impeller and shoots outward. Outlet, the discharge pipe flows out. At this time, at the center of the blade, the liquid is thrown around to form a vacuum low pressure zone with neither air nor liquid. The liquid in the liquid pool flows into the pump through the suction pipe under the action of the atmospheric pressure on the pool surface, and the liquid is continuous in this way. It is continuously sucked up from the liquid pool and continuously flows out of the discharge pipe. The basic parameters of submersible pumps: Including flow, head, pump speed, supporting power, rated current, efficiency, pipe diameter, etc.Main uses and scope of application of submersible pumps: Including construction drainage, water and agricultural drainage, industrial water circulation, and water used by urban and rural residents Supply, even rescue and disaster relief and so on. …

Centrifugal pump

Centrifugation is actually a manifestation of the inertia of an object. For example, when the umbrella rotates slowly, the water droplets will follow the umbrella. This is because the friction between the umbrella and the water droplets acts as the centripetal force for the water droplets. But if the umbrella rotates faster, this The friction is not enough to make the water droplets move in a circular motion, then the water droplets will move away from the umbrella to the outer edge. It is like using a rope to pull a rock in a circular motion. If the speed is too fast, the rope will break and the rock will be Flying out. This is the so-called centrifugal pump. The centrifugal pump is designed according to this principle. The high-speed rotating impeller blades drive the water to rotate, and the water is thrown out, so as to achieve the purpose of conveying. There are many kinds of centrifugal pumps. From the point of use, it can be divided into Civil and industrial pumps can be divided into clean water pumps, impurity pumps, corrosion-resistant pumps, etc. from the transportation medium. The basic structure of a 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 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 blade wheel are required to be smooth to reduce the friction loss of the water flow. To

2. The pump body is also called the pump housing, which is the main body of the water pump. Play a supporting and fixing role, and connect with the bracket for mounting the bearing. To

3. The role 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 to refuel properly. Generally, 2/3～3/4 of the volume is too much to generate heat, too little and there is noise and heat! The sliding bearing uses transparent oil as the lubricant, add oil to the oil level line. Too much oil will seep and drift along the pump shaft, and too little bearing will overheat and burn out, causing accidents! During the operation of the pump, the temperature of the bearing is up to 85 degrees and generally runs at about 60 degrees. If it is high, find out 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. The gap between the impeller inlet and the pump casing is too large to cause the water in the high-pressure area of ​​the pump to flow to the low-pressure area through this gap, which will affect the water output of the pump and reduce the efficiency! If the clearance is too small, friction between the impeller and the pump casing will cause abrasion. In order to increase the return 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 1.10mm. To

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, so that the water in the pump does not flow to the outside and the outside air does not enter 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! Maintain the normal operation of the pump. Therefore, special attention should be paid to the inspection of the stuffing box during the itinerant inspection of the pump operation! The packing should be replaced after 600 hours of operation. To

The working principle of the centrifugal pump The working principle of the centrifugal pump is: relying on the high-speed rotating impeller, the liquid gains energy under the action of inertial centrifugal force to increase the pressure. Before the pump works, the pump body and inlet pipe must be filled with water to prevent cavitation. When the impeller rotates quickly, the blades prompt the water to spin quickly, and the rotating water flies away from the impeller under the action of centrifugal force. After the water in the pump is thrown out, the central part of the impeller forms a vacuum area. The water in the water source is pressed into the inlet pipe through the pipe network under the action of atmospheric pressure (or water pressure). In this way, continuous water pumping can be realized. It is worth mentioning here that the centrifugal pump must be filled with water in the pump casing before starting, otherwise it will cause the pump body to heat up, vibrate, reduce the water output, and cause damage to the pump (referred to as “cavitation”) Cause an equipment accident! The so-called cavitation refers to: when the centrifugal pump is started, if there is air in the pump, because the density of the air is very low, the centrifugal force generated after rotation is very small, so the low pressure formed in the center of the impeller is not enough to keep the liquid level lower than the pump inlet The phenomenon that the liquid is sucked into the pump and cannot deliver the fluid. There are many types of centrifugal pumps, and the common classification methods are as follows:

1. According to the impeller suction mode: single-suction centrifugal pump and double-suction centrifugal pump;

2. According to the number of impellers: single-stage centrifugal pump and multi-stage centrifugal pump;

3. According to the impeller structure: open impeller centrifugal pump, semi-open impeller centrifugal pump, closed impeller centrifugal pump;

4. According to the working pressure: low pressure centrifugal pump, medium pressure centrifugal pump, high pressure centrifugal pump; 5. According to the position of the pump shaft: horizontal centrifugal pump side vertical centrifugal pump.