【 Weak current College 】 centrifugal pump does not cause analysis on water-Power By 【 China power house network 】

Centrifugal pump for its simple structure, convenient to use and maintain, more efficient and to become the most widely used in agricultural applications of a pump, but also sometimes mention the water and make people feel more trouble. Not to mention water this deliberate avoidance reasons analysed.

Fles and there is air in the pump

(1) some users in water pump starts before irrigation meet enough water; sometimes looks irrigation water from louver overflow, but did not turn the pump to drain the air completely, resulting in some air remains in fles or pump.

(2) and water pump contact fles level section of the application against the flow direction 0.5% downward slope, a water pump inlet connection

-End to the highest level, not completely. If tilted upwards, into the tube will ever left the air, reducing water and vacuum pumps, water-absorbing effect.

(3) pump packing for long-term use has been worn or packing pressing too loose, causing a lot of water from the filler and the gaps in the shaft bushing out, the result is an external air from these internal clearance to enter the water pump, affecting water pumping.

(4) the potential for long-term pipes, pipe wall underwater corrosion occurs after the hole, the water pump is declining, as these holes re-appear, air from holes into the pipes.

(5) into the water pipe elbow crack, fles and pump connections appear tiny gaps are likely to make the air enters into the water.


Pump speed is too low

(1) the human factor. A considerable part of the user as a result of his first wife motor damage, randomly matched with another motor driven, resulting in low flow, head and even can't water effects.

(2) transmission belt wear. There are many large off-pump uses the belt transmission, because long-term use, transmission belt wear and pine also, slipping occurs, which reduces the speed of the pump.

(3) improper installation. Two pulley Center distance is too small or two axle not peaceful, transmission belt tight side mounted to the above, the angle is too small for two pulley diameter calculation errors, as well as with shaft drive pump two larger axial eccentricity, will cause the pump speed changes.

(4), mechanical failure of the pump itself. Impeller and pump shaft fastening nut loose or shaft bending deformation, causing many to move directly to the impeller and the pump body friction, or bearing damage, which may reduce the speed of the pump.

(5) power machine maintenance not recorded. Motor burned by winding, excitation, maintenance winding turns, wire diameter, wiring methods change, or repair the fault does not completely exclude factors also makes the pump speed change.


Suction is too large

Some water is relatively dark, some water surface relatively flat, while neglecting the permissible suction pump, thus producing less absorbent or non-existent on the water absorption is not. Want to know the suction port Department can build vacuum is limited, the absolute vacuum suction of approximately 10 m water column, while the pump is not possible to establish absolute vacuum. And spend big, easy vacuum pump water gasification, water pumps work. So each pump has its maximum allowable suction, generally within 3 ~ 8.5 metres, installation of pumps is not only convenient and simple graphs.

Water inlet and outlet of resistance loss too large

Some users after a measurement, while water cistern or water tower to the surface of the vertical distance is slightly smaller than the pump lift, but mention water small or no water. The reason for this is often a pipe is too long, bend pipes, water flow pressure loss in piping is too large. The reason for this is often a pipe is too long, bend pipes, water flow pressure loss in piping is too large. Under normal circumstances a 90-degree bend more than 120 degrees bending resistance, each 90 degree elbow pipe head loss about 0.5 ~ 1 m, 20 m pipe resistance makes the lift losses of about 1 m. In addition, some users are free to pump inlet/outlet pipe diameter, which is also on the head.

The effect of other factors

(1) bottom valve does not open. Is usually due to the pump on hold for too long, the bottom valve gaskets glued to death, no washers of bottom valve may rust.

(2) bottom valve clogged filter network; or bottom valve potential water sludge layer causing filter clogging.

(3) serious impeller wear. Impeller blades with long-term use, wear, affecting water pump performance.

(4) gate valves or valve is at fault or jam can cause traffic decrease or even tied on the water.

(5) the export pipeline leakage may also affect water extraction.