JP4005299B2 - Air intake vortex prevention device for pump - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an air suction vortex preventing device for a pump caused by floating.
[0002]
[Prior art]
Conventionally, in the pump station, as shown in FIG. 4, a pump (vertical shaft pump) 85 is installed in the suction water tank 80, and the water flowing into the suction water tank 80 is drained to a predetermined place by driving the pump 85. is doing.
[0003]
On the other hand, in recent years, when the existing pumping station is updated, the discharge amount of the new pump 85 may be increased. In addition, the need to make the suction water tank 80 compact in the new pumping station has increased. If the discharge amount of the pump 85 is relatively increased with respect to the suction water tank 80 as described above, an air suction vortex is likely to be generated on the free surface of the water in the suction water tank 80 during the operation of the pump 85, and this vortex is generated by the pump. There is a fear that the air reaches the suction bell mouth 87 and sucks in air, and countermeasures have been important.
[0004]
Conventionally, in order to prevent the generation of the air suction vortex, there has been a method of installing a vortex prevention wall in the civil engineering structure. However, in the case of this method, since the eddy current prevention wall is installed in the existing pumping station, the pumping station must be stopped for a predetermined period for the civil engineering work. For this reason, the floating plate 89 shown in FIG. 4 has been used as a method for easily preventing the generation of the air suction vortex without stopping the pumping station. That is, the floating plate 89 is attached so as to surround the periphery of the pump 85 as shown in FIG. 4, and the water surface around the pump 85 where free vortex is likely to be generated is covered with the floating plate 89 to prevent the generation of free vortex. To do.
[0005]
However, since the pump insertion hole 83 provided in the floor 81 of the suction water tank 80 is formed in a size necessary for the pump 85 insertion, a floating plate 89 having a considerably larger diameter than the pump insertion hole 83 is inserted from the pump insertion hole 83. It is difficult to insert, and there is a problem that it is difficult to attach and remove.
[0006]
[Problems to be solved by the invention]
The present invention has been made in view of the above points, and an object thereof is to provide an air suction vortex preventing device for a pump that can be easily attached to and detached from the pump.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, the present invention is such that a pump is installed in the suction water tank by inserting a pump into a pump insertion hole provided on the floor above the suction water tank, and can be moved up and down around the pump. In an air suction vortex prevention device for a pump to which a float for preventing air suction vortex is attached, the float is divided into a plurality of parts having dimensions of being inserted / extracted from the pump insertion hole and fixed to each other. It is configured to have a structure in which the outer diameter is larger than the inner diameter of the pump insertion hole. Since this float can be reduced by dividing, it can be easily inserted and removed from the pump insertion hole.
[0009]
In addition, when there are a plurality of pumps, it is possible to provide a plurality of holes through which the pumps are inserted in the splittable float.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a view showing an example of a pump facility using a float according to a reference example of the present invention. FIG. 1 (a) is a schematic side sectional view, FIG. 1 (b) and FIG. It is an AA arrow line view of a). As shown in the figure, this pump facility has a pump base plate 53 fixed on a pump insertion hole 52 provided in a floor 51, and an electric motor (driving means) 17 is installed on the pump base plate 15 via an electric motor base 15. On the other hand, the suspension pipe 21, the discharge bowl 23, and the suction bell mouth 25 are attached to the lower end of the discharge elbow 19 fixed to the pump base plate 53 , and the discharge pipe 31 is attached to the discharge side of the discharge elbow 19.
[0011]
And in this reference example , the float 40 for air suction vortex prevention is attached surrounding the circumference | surroundings of the pump (vertical shaft pump) 10 installed in the suction water tank 55 as mentioned above so that it can move up and down.
[0012]
The float 40 is formed of a float bag that expands into a substantially donut shape by filling air (fluid having a specific gravity smaller than water). The float 40 is provided with an insertion hole 47 into which the pump 10 can be moved up and down. The shape of the float 40 is not limited to the donut shape as shown in FIG. 4B, but may be a “C” type that can be easily inserted into the pump as shown in FIG. If the float 40 is mounted on the pump 10 from the "C" -shaped cut, and then air is introduced, the attachment can be easily performed. It can also be easily removed. Various other shapes such as a rectangular shape and a polygonal shape may be used.
[0013]
When the electric motor 17 is driven, an impeller (not shown) installed in the suction bell mouth 25 is driven to rotate, so that water in the suction water tank 55 is sucked from the suction bell mouth 25 and discharged from the discharge pipe 31. Go.
[0014]
The water level in the suction water tank 55 is lowered by the operation of the pump and a free vortex is generated on the surface of the water. However, since the water surface around the pump is blocked by the float 40, no free vortex is generated. The vortex is sucked from the suction bell mouth 25 and does not hinder the pump operation.
[0015]
By the way, the float 40 is attached when the existing pump without the float 40 is removed and a new pump 10 having a larger discharge amount is attached, or when the newly installed float 40 is replaced with the pump 10. Or, it may be installed together with the pump 10 in a newly established pump station. In such a case, it is necessary to insert or remove the float 40 from the pump insertion hole 52. However, the float 40 according to the present embodiment can be easily reduced by removing the air inside. Even if the outer diameter at this time is larger than the inner diameter of the pump insertion hole 52, the insertion and removal can be performed very easily.
[0016]
Figure 2 is a diagram showing an example of pumping equipment using such floating 40-2 to implementation embodiments of the present invention, FIG. (A) is a schematic side sectional view, and FIG. (B) the figure (a) It is a BB arrow line view. In this pump facility, the only difference from the reference example shown in FIG. 1 is the structure of the float 40-2.
[0017]
That is, the float 40-2 according to this embodiment is configured by a plate made of a material having a specific gravity smaller than that of water, and is divided into three portions 40A, 40B, 40C, and flanges provided at the respective divided portions. 45 are mutually fixed by fixing means 46 such as bolts and nuts to constitute one float 40-2. The float 40-2 is provided with an insertion hole 47 into which the pump 10 can be moved up and down.
[0018]
If the float 40-2 is configured in such a manner that it can be divided, insertion and removal from the pump insertion hole 52 can be performed very easily as in the above-described reference example .
[0019]
FIG. 3 is a view showing an example of pump equipment using a float 40-3 according to another embodiment of the present invention. FIG. 3 (a) is a schematic side sectional view, and FIG. It is a CC arrow line view of). In this pump facility, the difference from the reference example and the embodiment shown in FIG. 1 and FIG. 2 is that a plurality of pumps 10 and 10 are installed in the same suction water tank 55, and one float is provided for each of the plurality of pumps 10 and 10. The point which attached 40-3, and the point which provided the stoppers 11 and 11 which protrude outward toward the lower part of the pumps 10 and 10. FIG.
[0020]
That is, the float 40-3 according to this embodiment is also composed of a plate made of a material having a specific gravity smaller than that of water, like the float 40-2 shown in FIG. 2, and is divided into eight portions 40a to 40h. The flanges 45 provided at the respective divided portions are fixed to each other by fixing means 46 such as bolts and nuts to constitute one float 40-3. The floating 40-3 is provided with two insertion holes 47, 47 into which the two pumps 10, 10 are inserted so as to be movable up and down.
[0021]
Also in this lifting 40-3, since divisible, as before Kimi facilities embodiment, insertion from the pump insertion hole 52, is taken out very easily.
[0022]
In the case of the floating 40-3, since the two pumps 10 and 10 support the floating 40-3, the surface thereof is easily maintained in a plane perpendicular to the vertical axis of the pumps 10 and 10, and thus may be inclined obliquely. Can be reliably prevented.
[0023]
In the case of the float 40-3, since the stoppers 11 and 11 are provided, even if the water level in the suction water tank 55 is extremely lowered, the float 40-3 follows this and comes off from the pumps 10 and 10. There is no problem. In particular, when these pumps 10 and 10 are operated as preceding standby pumps, the water level is extremely lowered, and thus is particularly effective.
[0024]
The number of pumps 10 to be installed may be three or more. In that case, the insertion hole 47 is provided according to the number.
[0025]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea described in the claims and the specification and drawings. Is possible. Note that any shape, material, or structure not directly described in the specification and drawings is within the scope of the technical idea of the present invention as long as the effects and advantages of the present invention are exhibited. For example, the fluid filled in the float 40 shown in FIG. 1 may be a gas other than air or a liquid.
[0026]
【The invention's effect】
As described above in detail, according to the present invention, even when the pump insertion hole of the suction water tank is smaller than the outside diameter of the float, the float can be easily inserted and removed from the pump insertion hole, There is an excellent effect that it can be easily attached and detached.
[Brief description of the drawings]
FIG. 1 (a) is a schematic side sectional view showing an example of pump equipment using a float 40 according to a reference example of the present invention. FIG. 1 (b) and FIG. It is an AA arrow line view of a).
[2] Figure 2 (a) is a schematic side sectional view showing an example of pumping equipment using such floating 40-2 to implementation embodiments of the present invention, FIG. 2 (b) Figure 2 (a) It is a BB arrow line view.
FIG. 3 (a) is a schematic side sectional view showing an example of pump equipment using a float 40-3 according to another embodiment of the present invention, and FIG. 3 (b) is a diagram of FIG. 3 (a). It is a CC arrow line view.
FIG. 4 is a schematic side sectional view showing an example of conventional pump equipment.
[Explanation of symbols]
10 Pump 17 Electric motor (drive means)
19 Discharge elbow 21 Suspension tube 23 Discharge bowl 25 Suction bell mouth 31 Discharge tube 40 Float 45 Flange 46 Fixing means 47 Insert hole 51 Floor 52 Pump insert hole 55 Suction water tank 40-2 Float 40-3 Float 11 Stopper

Claims (2)

A pump is installed in the suction water tank by inserting a pump into a pump insertion hole provided on the floor above the suction water tank, and a float for preventing air suction vortex is attached around the pump so as to be movable up and down. In the pump air suction vortex prevention device,
The float is divided into a plurality of parts having dimensions to be inserted / removed from the pump insertion hole, and fixed to each other to form one float with an outer diameter larger than the inner diameter of the pump insertion hole. An air suction vortex preventing device for a pump, characterized in that it is configured. To the pump, the floating air suction vortex prevention of pump according to claim 1, characterized in that a stopper to prevent the outside from the bottom of the pump by projecting outward of the pump apparatus.

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