Plastic centrifugal pump

Abstract

The invention discloses a plastic centrifugal pump. The plastic centrifugal pump comprises a pump shell, a main shaft, a shaft seal on the main shaft, a bearing base, and an impeller mounted at the end part of the main shaft and positioned in a volute cavity of the pump shell; the impeller includes an impeller spoke plate, and an impeller blade on the impeller spoke plate; and the inner bending side incision of the tail part of the impeller blade is provided with an inclined guide angle for increasing the flowing angle of a fluid thrown out from a liquid outlet of an impeller runner to forwards flow the fluid in the direction of the liquid outlet of the impeller runner. The thickness and the intensity of the plastic impeller blade are not changed, and the form of the tail part of the impeller blade is only changed, so that the moving direction of the fluid is changed, the generation or / and increment of an eddy current area, a reverse current area and a slow flowing area in a pump cavity is reduced, the convection impact of the fluid is reduced, and the efficiency of the pump is promoted.

Description

technical field [0001] The invention relates to the improvement of a plastic centrifugal pump, which belongs to the machinery industry by improving the efficiency of the lifting pump by about 2-4%. Background technique [0002] Plastic centrifugal slurry pump is a pump widely used in chemical industry, environmental protection, smelting, electric power, non-metallic mineral processing and other industrial fields to transport slurry. It has the advantages of good chemical resistance and anti-corrosion, especially ultra-high molecular weight polymer Centrifugal pumps made of vinyl also have excellent wear resistance, so they can be used to transport corrosive and abrasive slurry, ore slurry, etc. Moreover, the national consumption is huge. It is conservatively estimated that there are about 2 million units in operation, and the annual market sales are nearly 200,000 units. Although the centrifugal pump made of ultra-high molecular weight polyethylene has excellent corrosion r...

AI Technical Summary

Problems solved by technology

[0003] The main reason why the plastic impeller affects the efficiency of the pump: the blades of the metal impeller are made of metal and have high strength, so they can be processed into thin blades with good blade shape, so the efficiency is high; while the blades of the plastic impeller are low in strength and poor in temperature resistance, so Only thicker blades can be made to improve the strength of the blades and prolong the wear life of the impeller; otherwise, if the plastic impeller is processed into the same thin blade as the metal impeller, the service life of the impeller will be shortened due to insufficient strength

like Figure 1~3 As shown, the blade 1.1 of the plastic impeller 1 is thickened, which makes the tail blade 1.1.1 at the inner arc of the impeller grow, changes the angle of the guide angle at the liquid outlet of the impeller blade, and changes the flow velocity of the liquid at the liquid outlet of the impeller Conflict with the flow direction and the flow direction of the fluid 2.1 in the pump cavity of the pump casing 2, so that the fluid in the pump volute cavity produces a spiral flow area 2.1. Increased resistance reduces pump efficiency

Therefore, it is difficult to find a solution for the best of both worlds between the thickness (strength) of the impeller of the plastic pump and the efficiency of the pump, that is, thick blades will cause low pump efficiency, and thin blades will cause short service life of the pump.

[0004] Some people in the industry also use metal embedded parts in the impeller blades to reduce the thickness of the plastic impeller blades and improve pump efficiency by increasing the steel strength of the blades. Reduce the yield of products and increase production costs. Therefore, the technology has not been widely promoted and applied for decades since the plastic pump was on the market.

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