JPH0925895A - Downsized shape of pump delivery volute casing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the width required for the installation of a pump by making the whole delivery passage width equal to the whole suction passage width. SOLUTION: A first delivery passage 2 from a first tongue end A2 with a tongue end angle θ1 of 100 deg.-140 deg., and a second delivery passage 5 from a second tongue end B2 with a tongue end angle θ1 of 280 deg.-320 deg. branch off at a branch point S. The whole delivery passage width W3 is formed to be equal to the whole suction passage width W, and offset is made zero.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compact shape of a pump discharge volute casing.

[0002]

2. Description of the Related Art In recent years, pump stations, which are planned as urban flood countermeasures, tend to have a large capacity and a high head year by year, and in order to reduce the cost increase accompanying the enlargement of the stations, the pumps should be made compact. It is important to. Therefore, it is desired to reduce the installation width of the pump by making the pump compact and to reduce the cost in terms of civil engineering costs.

In order to make the pump compact, it is necessary to reduce the cross-sectional area of the suction passage, that is, to speed up the flow. However, although there is a concern that vortices will be generated as the flow speed increases, the applicant of the present invention has proposed a technique for preventing the generation of vortices in Japanese Patent Application No. 6-231005, which aims to increase the suction flow velocity, that is, the suction passage. Made possible to be compact.

Therefore, even if the suction passage can be made compact, if the entire width of the discharge passage is not reduced, the pump installation width required for pump installation becomes large, and the civil engineering cost and other costs are reduced. Since it is the same as the conventional one, it is desired to reduce the width of the discharge flow channel.

A conventional discharge double volute casing 1
At 0, as shown in FIG. 2, the winding start tongue position, that is, the tongue ends A1 and B1 is set to the tongue end angle θ from the cross section I perpendicular to the flow direction F indicated by the arrow near 45 ° and 225 °. The first discharge flow path 11 from the tongue end A1 and the tongue end B.
The flow passages 11 and 12 are arranged in parallel in a direction orthogonal to the axis a of the pump in order to direct the flow in the volute nozzle direction, that is, the discharge port direction, while ensuring each cross-sectional area from the first discharge passage 12 to the second discharge passage 12. Therefore, it is necessary to increase the discharge passage overall width W1.

Further, the total width W1 of the discharge flow path is equal to the total width W of the suction flow path.
Therefore, the required pump installation width W2 was also increased.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a compact pump discharge volute casing shape which reduces the required pump installation width.

[0008]

According to the present invention, in the discharge double volute casing, the first tongue end of the first discharge passage is provided at the position of the tongue end angle of 100 ° to 140 °, and the second discharge passage is formed. The second tongue end of is provided at a position of a tongue end angle of 280 ° to 320 °, and the first and second discharge flow paths are branched from each other.

Further, according to the present invention, the entire width of the discharge passage is formed to be equal to the entire width of the suction passage, and the offset amount between the suction passage and the entire width of the discharge passage is set to zero.

In the discharge double volute casing, the first from the first tongue end having a tongue end angle of 100 ° to 140 °.
The discharge flow path and the second discharge flow path from the second tongue end having a tongue end angle of 280 ° to 320 ° are mutually branched to form the discharge flow path total width equal to the suction flow path total width, and suction. The offset between the flow passage and the entire width of the discharge flow passage is set to zero.

In the compacted shape of the pump discharge volute casing constructed as described above, the pump discharge volute casing has a total width equal to the suction flow passage, and the offset amount of both flow passages is set to zero, whereby the pump The total installation width is reduced.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, the first discharge flow path 2 from the first tongue end A2 having a tongue end angle θ1 of the discharge double volute casing 1 of 100 ° to 140 ° (135 ° in the illustrated example).
And the second discharge flow path 5 from the second tongue end B2 having the tongue end angle θ1 of 280 ° to 320 ° (315 ° in the illustrated example),
At the branch point S, the branch is made in a direction orthogonal to the axis a of the pump.

The outer portion 3 of the first discharge passage 2 is located on an extension of one outer portion w1 of the entire suction passage width W, and the inner portion 4 is a cross-sectional area of the conventional first discharge passage 11. It is formed in a shape that can secure.

On the other hand, the outer side portion 6 of the second discharge flow path 5 is located on the extension line of the other outer side portion w2 of the entire suction flow path width W, in the illustrated example, the curved portion from the first tongue end A2. Is formed by. Then, the inner surface 7 is the second discharge channel 1 of the related art.
The curved portion 7a is bent from the branch point S toward the outer portion 6 side so as to secure the cross-sectional area of 2, and the curved portion 7b is continuously inverted to the curved portion 7a and is bent toward the inner portion 4 side. .

Next, the operation will be described.

Therefore, the total width W3 of the discharge flow path is equal to the total width W of the suction flow path, and the offset between the total widths W and W3 is zero. As a result, the required pump installation width W4 becomes the same as the suction passage overall width W, which is significantly reduced compared to the conventional case.

The tongue angle θ1 of the first tongue end A2 is 1
If the angle is 00 ° or less or 140 ° or more, the shape shown in the drawing is used in which the suction passage total width W is effectively used for the discharge passage total width W3 without impairing the pump efficiency, that is, without increasing the discharge passage loss. Difficult to form.

Further, the tongue end angle θ1 of the second tongue end B2 is 2
If the angle is 80 ° or less or 320 ° or more, it is difficult to form a shape for the same reason as above.

[0020]

EFFECTS OF THE INVENTION Since the present invention is configured as described above, it is possible to reduce the entire discharge flow passage width, that is, the pump installation required width, and reduce installation civil engineering costs.

[Brief description of drawings]

FIG. 1 is a top view showing one embodiment of the present invention.

FIG. 2 is a top view showing a conventional shape.

[Explanation of symbols] A1, B1 ... Tongue end A2 ... First tongue end B2 ... Second tongue end F ... Flow direction W ... Suction flow path full width W1, W3 ... Discharge Full width of flow path W2, W4 ... Necessary width for pump installation w1, w2 ... Outer surface part θ, θ1 ... Tongue end angle 1, 10 ... Discharge double volute casing 2, 11 ... First discharge flow Channels 3, 6 ... Outer side section 4, 7 ... Inner side section 5, 12 ... Second discharge flow path 7a, 7b ... Curved section

Claims (2)

[Claims] 1. In a discharge double volute casing, the first tongue end of the first discharge flow passage has a tongue end angle of 100 ° to 14 °.
It is characterized in that it is provided at a position of 0 °, the second tongue end of the second discharge flow passage is provided at a position of a tongue end angle of 280 ° to 320 °, and the first and second discharge flow passages are branched from each other. Compact shape of pump discharge volute casing. 2. The compact shape of the pump discharge volute casing according to claim 1, wherein the discharge flow passage has a total width equal to the suction flow passage and the offset amount between the suction flow passage and the discharge flow passage is zero. .