CN2103038U

CN2103038U - Small flow supper low-rate revolution impeller

Info

Publication number: CN2103038U
Application number: CN 91219794
Authority: CN
Inventors: 文培仁; 孔凡渝; 张兴林
Original assignee: Hefei Universal Machinery Inst Ministry Of Machine-Building And Electronics In
Current assignee: Hefei Universal Machinery Inst Ministry Of Machine-Building And Electronics In; Hefei General Machinery Research Institute Co Ltd
Priority date: 1991-08-13
Filing date: 1991-08-13
Publication date: 1992-04-29

Abstract

The utility model provides a mew-type small flow super low-rate revolution impeller, which is suitable for a small flow low-rate revolution centrifugal pump. The utility model can be suitable for the situation which needs small flow and high delivery lift. Furthermore the utility model reduces the manufacture cost, increases the quality and level of product and saves energy. The mew-type small flow super low-rate revolution impeller is characterized in that short vanes are respectively distributed near the rear surfaces of long vanes. The inlet of the short vanes is at 0.8D (D2-the external diameter of the impeller), and the width b of the impeller is equal to the width of the outlet b2 of the impeller.

Description

Small flow supper low-rate revolution impeller

The utility model is the impeller of using on a kind of centrifugal pump.

Centrifugal pump impeller now commonly used, (N wherein: revolution r/min when specific speed NS==50～1000; Q: flow m ³/ s; H: lift m), can carry out designing and calculating by common method.But when specific speed NS≤50, particularly NS≤30, flow Q≤5m ³During/h, it is very little that its exit width b2 becomes, and is difficult to casting.Conventional calculating impeller outlet width formula is as follows:

b2＝K _b2 ³ ；K _b2＝0.78

，

Get N=2900r/min

As Q≤5m ³/ h, NS≤30 o'clock, b2≤3mm

Q≤3.2m ³/ h, NS≤23 o'clock, b2≤2.5mm

Narrow like this exit width, manufacturing are very difficult, can increase reject rate greatly, perhaps cause the performance of impeller to be offset to large-capacity point, thereby can not get desirable Ultra-low Specific revolution centrifugal pump impeller.When needing above-mentioned small flow Ultra-low Specific revolution centrifugal pump in the past, often be forced to adopt big pump, make its in the small flow district, the operation of inefficient district, consume bigger power, cause energy waste.

The purpose of this utility model provides a kind of small flow Ultra-low Specific revolution impeller that has improved, and its advantage is: ultra-low specific speed NS≤30, exit width b2 〉=definite value, the little Q≤5m of flow ³/ h, the high η of efficient=30～35%, (JB/TQ467-86 one step single sucking chemical centrifugal pump quality grading A level product regulation η=23～29%) cavitation performance is good, NPSH=1.2m, performance characteristic does not have hump, manufacturing process performance good (seeing Fig. 1, Fig. 2).

The utility model is to realize like this, increased the exit width of impeller, b2 〉=definite value, improved technology capability, impeller adopts more blade, and deviated splitter vane distinguishingly distributes, and make short blade (2) import be arranged in 0.8D2 place (D2-impeller outer diameter), overcome effectively owing to strengthen the interior separation of flow of impeller that exit width b2 may bring simply, improved the efficient of pump, characteristic curve can not occurred moving disadvantageous hump phenomenon.According to velocity distribution in the Ultra-low Specific revolution impeller blade runner, short blade (2) is arranged near place, linear leaf (1) back side, make velocity distribution even, improved the hydraulic performance of impeller and delivery chamber, because the effect of squeezing of short blade (2) is constantly reduced to short blade (2) import front vane front relative velocity by impeller inlet, and the separation of flow, the vortex of fluid on the blade of generation, increase the hydraulic loss phenomenon and all can suppress, short blade (2) has also increased limited number of blade correction factor.

Blade has adopted and has waited circular arc straight blade shape, is convenient to processing, and design parameter is coincide with making easily, and designing requirement easily realizes, has reduced the variation of making the pump performance that reason brings.

Because above measure, improve lift of pump, and adopted impeller width b to equal impeller outlet width b2=constant (be approximately calculated value 2 times), Q≤5m is satisfied in measures such as appropriate design volute throat size ³/ h, NS=30 or the more more requirement of low specific speed of small flow.

Further specify it below in conjunction with embodiment.

Fig. 1. the pump performance plotted curve

Fig. 2. the cavitation performance plotted curve

Fig. 3 .a.b. blade wheel structure figure.

Among Fig. 3, impeller width b equals impeller outlet width b2=5mm, each 6 in long and short blade, and short blade (2) is distributed near linear leaf (1) back side, and short blade (2) import is at the 0.8D2 place, and blade is the circular arc equal thickness.Behind casting, the clear sand, insert the machine tooling such as grade through turnning and milling and make shape among the figure.

The utility model has the advantages that: for the small flow supper low-rate revolution centrifugal pump provides good hydraulic model, be widely used in chemical flow-process pump, canned motor pump, magnetic drive pump and other needs the occasion of low discharge high-lift centrifugal pump, be convenient to reduce production costs, improve the quality of products, level, energy savings.

Claims

1, a kind of novel small flow Ultra-low Specific revolution impeller, include linear leaf (1) short-movie (2), it is characterized in that: short blade on the impeller (2) is arranged near linear leaf (1) back side, short blade (2) import is located at 0.8D2 (D2-impeller outer diameter), impeller width b equals impeller outlet width b2, its width is about constant, is 2 times of calculated value approximately.