Water pumps are generally classified according to the structure and function of the pump, and sometimes according to the needs of the use of the department, use, power type and hydraulic performance of the pump classification.
(1) according to the departments of use, there are agricultural pumps (agricultural pumps), working pumps (industrial pumps) and special pumps.
(2) according to the purpose of the water pump, sand pump, mud pump, sewage pump, sewage pump, well pump, submersible pump, sprinkler pump, household pump, firepump.
(3) according to the type of power, there are manual pump, animal pump, foot pump, wind pump, solar pump, electric pump, motor pump, water wheel pump, internal combustion pump, water hammer pump, etc.
(4) according to the working principle, there are centrifugal pump, mixed flow pump, axial flow pump, vortex pump, jet pump, positive displacement pump (screw pump, piston pump, diaphragm pump), chain pump, electromagnetic pump, liquid ring pump.
Second, the working principle of the pump
(1) working principle and characteristics of centrifugal pump
1. Working principle of centrifugal pump
Before the pump is started, fill the pump and the inlet pipe with water. After the pump is running, under the centrifugal force generated by the high-speed rotation of the impeller, the water in the impeller runner is thrown around and pressed into the volute, forming a vacuum at the inlet of the impeller, and the water in the pool is in the outside atmosphere.Then the inhaled water was thrown out by the impeller through the volute and into the outlet pipe.Thus it can be seen that if the impeller of the centrifugal pump is constantly rotating, it can continuously absorb water and pressure water, and the water can be continuously raised from the low to the high or far away.To sum up, the centrifugal pump is due to the centrifugal force generated by the high-speed rotation of the impeller, the water will be higher, so it is called the centrifugal pump.
2, the general characteristics of the centrifugal pump
(1) along the flow direction of the centrifugal pump, the water is sucked in along the axial direction of the impeller and flows out perpendicular to the axial direction, that is, the flow direction in and out is 90° to each other.
(2) since the centrifugal pump forms a vacuum suction through the entrance of the impeller, it is necessary to infuse water into the phase pump and the suction pipe before starting, or to pump air with a vacuum pump to discharge air to form a vacuum. Besides, the pump shell and suction pipe must be strictly sealed without air leakage, otherwise there will be no vacuum and no water can be sucked.
(3) since it is impossible to form an absolute vacuum at the inlet of the impeller, the suction height of the centrifugal pump cannot exceed 10 meters. In addition to the loss along the water flow through the suction pipeline, the actual allowable installation height (the height of the pump axis from the suction water surface) is much less than 10 meters.If the installation is too high, it will not absorb water;In addition, because the mountain area is lower than the plain atmospheric pressure, so the same pump in the mountain area, especially in the high mountain installation, its installation height should be reduced, otherwise it can not absorb water.