Impeller structure of rotary shell type pump

Abstract

The invention discloses an impeller structure of a rotary shell type pump, which comprises impeller blades positioned between a front cover plate and a back cover plate. The adjoining impeller blades are formed into impeller flow passageways. The impeller structure is characterized in that each impeller flow passageway consists of an impeller inlet flow passageway and an impeller outlet flow passageway; each impeller inlet flow passageway is an arc flow passageway, wherein the length of the arc flow passageway is 60-70% of that of the impeller flow passageway, and an inclined angle beta1 arranged between the midline of each impeller inlet flow passageway and an inlet distribution circle is from 20 to 40 degrees; and each impeller outlet flow passageway is provided with two outlet radial branch flow passageways. The impeller flow passageways of the impeller structure effectively restrains the generation of axial whirlpool and flow separation; a smaller inlet angle can lead the impact loss of the inlet to be reduced; the branch of the outlet flow passageway leads the liquid which flows into a shell to be more even; and the milling machine of the flow passageways can obtain small surface roughness to achieve the aim for improving the waterpower efficiency of the impeller.

Description

Technical field [0001] The invention relates to an impeller structure of a pump. Specifically refers to the impeller structure of a low specific speed pump that is used to transport liquids with small flow and high head requirements. The specific speed range of the above low specific speed pump is n s = 8~60. Background technique [0002] With the requirements of reduced flow and increased lift, the specific speed of the pump continues to decrease. When specific speed n s When it is lower than 20, usually the efficiency of the centrifugal pump will drop below 30%. In the range of vane pumps, it is generally designed as a partial flow pump. At present, in the domestic design of fixed-shell high-speed partial flow pump impeller, single-stage open impeller structure and closed long and short blade impeller structure are generally adopted. The impeller and the casing of the rotary shell partial flow pump rotate together. Most designs at home and abroad use semi-open impeller and c...

AI Technical Summary

Problems solved by technology

These effects produce hydraulic losses both within the impeller and in the fluid leaving the impeller

The radial straight-flow channel impellers for rotary casing pumps proposed by some developed countries inevitably have impact losses at the impeller inlets, and the obvious pulsating outflow at the impeller outlets will also cause hydraulic losses, and it is also very easy to cause unstable operation and flow noise.

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