Pump, installation method for pump, pump station and manufacturing method for pump station

Abstract

To prevent a pump from sucking in vortexes.SOLUTION: A pump for pumping water in a suction water tank comprises a main shaft extending vertically, an impeller rotated by the main shaft, and a pump casing housing the impeller therein, where a suction port of the pump casing is inclined toward an upstream side of a water flow in the suction water tank as it approaches an upper part.SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] The present invention relates to a pump, a method for installing a pump, a pump station and a method for manufacturing a pump station. [Background technology]

[0002] At pumping stations where pumps for draining rivers and sewage are installed, there is a need to lower the drainage water level in the suction tank due to changes in the upstream flood prevention target area and uneven settlement over time of inflow water channels, etc. In addition, there is a need to increase the number of pumps to deal with sudden rainfall such as the recent torrential downpours.

[0003] A drop in the drainage water level in the suction tank can cause vortices to form on the free surface of the water in the suction tank. If the vortex is drawn into the pump, it becomes an air-sucking vortex, and air enters the pump. This can cause abnormal vibrations and lead to pump failure. For this reason, the position of the pump suction port is lowered, but if the suction port is close to the bottom of the suction tank, underwater vortices are more likely to form from the bottom or side walls of the tank. In addition, underwater vortices are more likely to form due to the increased flow speed of the suction tank caused by the increase in pump power. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2015-78679 A Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to prevent the pump from ingesting vortexes. [Means for solving the problem]

[0006] According to one aspect of the present invention, [1] A pump that pumps water in a suction tank, A main axis extending in a vertical direction; An impeller rotated by the main shaft; a pump casing that houses the impeller therein; The pump is provided such that the suction port of the pump casing is inclined toward the upstream side of the water flow in the suction water tank as it approaches the upper part.

[0007] [2] [1] The pump according to the present invention, The pump casing comprises: an upper bell mouth located below the impeller and having an open lower end; The suction tank may also have a lower bell mouth having a shape formed by cutting a vertically extending cylinder diagonally so that the suction port extends downward from the lower end of the upper bell mouth and is inclined toward the upstream side of the water flow in the suction tank as it approaches the upper part.

[0008] [3] [1] or [2], wherein the pump The suction port may be inclined upward at an angle of 15 to 75 degrees with respect to the horizontal plane.

[0009] [4] [1] or [2], wherein the pump The suction port may be inclined upward at an angle of 15 to 45 degrees with respect to the horizontal plane.

[0010] [5] [1] to [4], wherein the pump The end face of the suction port may be provided with projections and recesses.

[0011] [6] [1] to [4], wherein the pump The air intake may further include a louver provided on an end surface of the air intake.

[0012] [7] [1] to [4], wherein the pump The pump may include a louver extending from an interior of the pump casing to at least an end face of the suction port.

[0013] [8] [1] The pump according to the present invention, The pump casing comprises: an upper bell mouth located below the impeller and having an open lower end; The upper bell mouth may have a vortex control member having a shape formed by cutting a vertically extending rectangular prism diagonally so that the suction port extends downward from the lower end of the upper bell mouth and is inclined toward the upstream side of the water flow in the suction tank as it approaches the upper part.

[0014] [9] [1] to [8], wherein the pump The pump casing may be a cylindrical column.

[0015]

[10] [1] to [9], wherein the pump A baffle plate may be provided on the outer surface of the pump casing and inclined so as to approach the bottom surface of the suction tank as it approaches the downstream side.

[0016] According to one aspect of the present invention,

[11] A main axis extending in a vertical direction; An impeller rotated by the main shaft; an upper bell mouth located below the impeller and having an open lower end; A method for installing a pump having a shape obtained by cutting a vertically extending cylinder obliquely and a lower bell mouth that forms a pump suction port at a lower portion, in a suction tank, comprising the steps of: There is provided a method for installing a pump, the method including a step of attaching the lower bell mouth to a lower end of the upper bell mouth so that the suction port is inclined toward the upstream side of the water flow in the suction tank as it approaches the upper part.

[0017] According to one aspect of the present invention,

[12] A pump yard in which a plurality of pumps according to any one of [1] to

[10] are arranged, A pump yard is provided, wherein each of the plurality of pumps is arranged such that its suction port is orthogonal to the direction in which water flows in.

[0018]

[13] In the pump yard according to

[12] , The plurality of pumps may be arranged side by side on a straight line orthogonal to the water flow.

[0019]

[14] In the pump yard according to

[12] or

[13] , A partition wall may not be provided between each of the plurality of pumps and an adjacent pump.

[0020] According to one aspect of the present invention,

[15] A method for manufacturing a pump yard is provided, including the step of arranging a plurality of pumps according to any one of [1] to

[10] such that its suction port is orthogonal to the direction in which water flows in.

[0021] According to one aspect of the present invention,

[16] A pump yard in which a plurality of pumps according to any one of [1] to

[10] are arranged, The plurality of pumps are arranged side by side on a straight line along the direction in which water flows in between a first side wall of a suction water tank and a second side wall facing the first side wall, A first pump arranged most upstream among the plurality of pumps is arranged such that its suction port is orthogonal to the direction in which water flows in, A second pump arranged second from the upstream side among the plurality of pumps is arranged such that its suction port faces the side of the first pump on the first side wall. A pump yard is provided.

[0022]

[17] In the pump yard according to

[16] , A third pump that is disposed third from the upstream side among the plurality of pumps may be disposed such that its suction port faces a side of the second pump in the second side wall.

[0023]

[18]

[16] or

[17] , wherein the pumping station It is not necessary to provide a partition wall between each of the plurality of pumps and an adjacent pump.

[0024]

[19]

[16] to

[18] , wherein the pump station A partition wall extending in the direction in which water flows may be provided between each of the plurality of pumps and an adjacent pump.

[0025] According to one aspect of the present invention,

[20] [1] to

[10] , a plurality of pumps are disposed between a first side wall of a suction tank and a second side wall facing the first side wall, They are lined up in a straight line along the direction of the water flow, The first pump, which is disposed at the most upstream of the plurality of pumps, has a suction port perpendicular to the direction in which water flows in, A method for manufacturing a pumping station is provided, which includes a step of positioning a second pump, which is the second most upstream of the plurality of pumps, such that its suction port faces the first pump side of the first side wall.

[0026] According to one aspect of the present invention, [twenty one] A pump station comprising a pump according to any one of [1] to

[10] , The pump is disposed at a position where a distance from the pump to a first side wall of the suction tank is different from a distance from the pump to a second side wall opposite to the first side wall, A pumping station is provided in which the pump is positioned so that its suction is perpendicular to the direction in which the water flows.

[0027] [twenty two] In the pump field described in

[21] , The suction water tank has a wider portion on the downstream side than on the upstream side, and the pump may be arranged in the wider portion.

[0028] According to one aspect of the present invention,

[23] The pump according to any one of [1] to

[10] is placed at a position where the distance from the pump to the first side wall of the suction water tank is different from the distance from the pump to the second side wall facing the first side wall, and a method for manufacturing a pump field is provided, which includes a step of arranging the suction port thereof so that it is orthogonal to the direction in which water flows in.

Effect of the Invention

[0029] It is possible to suppress the pump from sucking in vortices.

Brief Description of the Drawings

[0030] [Figure 1A] Schematic diagram of the pump 100 according to the first embodiment. [Figure 1B] Schematic diagram of the pump 100 shown in FIG. 1A viewed from the direction of arrow A. [Figure 1C] Schematic diagram of the pump 100 shown in FIG. 1A viewed from the direction of arrow B. [Diagram 2] Schematic side view of the pump 100 according to the first modification. [Figure 3A] Schematic side view of the pump 100 according to the second modification. [Figure 3B] Schematic side view of the pump 100 according to the second modification. [Figure 3C] Schematic side view of the pump 100 according to the second modification. [Figure 4] Schematic side view of the pump 100 according to the third modification. [Figure 5A] Schematic side view of the pump 100 according to the fourth modification. [Figure 5B] Schematic perspective view of the pump 100 according to the fourth modification. [Figure 5C]FIG. 11 is a schematic bottom view of a pump 100 according to a fourth modified example. [Figure 6A] FIG. 13 is a schematic side view of a pump 100 according to a fifth modified example. [Figure 6B] FIG. 13 is a schematic side view of a pump 100 according to a fifth modified example. [Figure 7A] FIG. 13 is a schematic side view of a pump 100 according to a sixth modified example. [Figure 7B] FIG. 13 is a schematic side view of a pump 100 according to a sixth modified example. [Figure 8] FIG. 11 is a schematic diagram of a pump station according to a second embodiment, viewed from above. [Figure 9A] FIG. 11 is a schematic diagram of a pump station according to a third embodiment, viewed from above. [Figure 9B] FIG. 11 is a schematic diagram showing a pumping station according to a modified example of the third embodiment, viewed from above. [Figure 10A] 10 is a schematic side view of a pump 100 suitable for the pumping station of FIG. 9. [Figure 10B] 10 is a schematic top view of a pump 100 suitable for the pumping station of FIG. 9. [Figure 10C] FIG. 10C is a schematic top view of the pump 100 according to a modified example of FIG. 10B. [Figure 11A] 10 is a schematic side view of another pump 100 suitable for the pumping station of FIG. 9. [Figure 11B] 10 is a schematic top view of another pump 100 suitable for the pump station of FIG. 9; [Figure 11C] FIG. 11C is a schematic top view of another pump 100 according to a modification of FIG. [Figure 12A] FIG. 11 is a schematic diagram of a pump station according to a fourth embodiment, viewed from above. [Figure 12B] FIG. 11 is a schematic diagram of another pump station according to the fourth embodiment, viewed from above. [Figure 12C] FIG. 11 is a schematic diagram of yet another pump station according to the fourth embodiment, viewed from above. [Figure 13A] 1 is a schematic diagram showing a pumping station to which a pump 100 according to an embodiment of the present invention can be applied, as viewed from above. [Figure 13B] 1 is a schematic diagram showing a pumping station to which a pump 100 according to an embodiment of the present invention can be applied, as viewed from above. [Figure 13C]1 is a schematic diagram showing a pumping station to which a pump 100 according to an embodiment of the present invention can be applied, as viewed from above. [Figure 13D] 1 is a schematic diagram showing a pumping station to which a pump 100 according to an embodiment of the present invention can be applied, as viewed from above. [Figure 13E] 1 is a schematic diagram showing a pumping station to which a pump 100 according to an embodiment of the present invention can be applied, as viewed from above. [Figure 13F] 1 is a schematic diagram showing a pumping station to which a pump 100 according to an embodiment of the present invention can be applied, as viewed from above. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Hereinafter, an embodiment of the present invention will be specifically described with reference to the drawings.

[0032] (First embodiment) The first embodiment is assumed to be a pump 100 that pumps water in a suction tank. Figs. 1A to 1C are schematic diagrams of the pump 100 according to the first embodiment. Fig. 1A is a schematic diagram of the pump 100 viewed from upstream to downstream of the water flow in the suction tank. Fig. 1B is a schematic diagram of the pump 100 shown in Fig. 1A viewed from the direction of arrow A. Fig. 1C is a schematic diagram of the pump 100 shown in Fig. 1A viewed from the direction of arrow B. Arrow F indicates the direction of the water flow.

[0033] This pump 100 is installed near a rear wall 101 and a side wall 102 of the suction sump. The pump 100 includes a main shaft 1 extending vertically, an impeller 2 rotated by the main shaft 1, and a pump casing 3 that houses the impeller 2. There are no particular limitations on the drive mechanism of the pump 100, and possible combinations include a combination of a vertical reducer and an electric motor, a combination of a bevel gear reducer and an electric motor, a combination of a bevel gear reducer and a diesel engine, a combination of a bevel gear reducer and a gas turbine engine, etc.

[0034] One feature of this embodiment, which can be easily seen in FIG. 1B, is that the suction port 3a of the pump casing 3 is inclined toward the upstream side of the water flow in the suction tank as it approaches the upper part.

[0035] As a specific configuration example, the pump casing 3 has a lifting pipe 31, an upper bellmouth 32, and a lower bellmouth 33. The lifting pipe 31 houses the impeller 2 inside. The upper bellmouth 32 is located below the impeller 2 and is open at its upper and lower ends. The lifting pipe 31 is attached to the opening at the upper end. The lower bellmouth 33 extends downward from the lower end of the upper bellmouth 32.

[0036] The lower bellmouth 33 has a shape obtained by cutting a vertically extending cylinder obliquely so that the suction port 3a is formed which is inclined towards the upstream side of the water flow in the suction tank as it approaches the upper part.

[0037] Therefore, the lower bellmouth 33 extends deeper the closer it is to the rear wall 101 (the further downstream). For example, as shown in Fig. 1B, the length a from the upper end to the lower end of the part of the lower bellmouth 33 closest to the rear wall 101 is longer than the length b from the upper end to the lower end of the part of the lower bellmouth 33 farthest from the rear wall 101.

[0038] To install such a pump 100 in a suction tank, the lower bell mouth 33 is attached to the lower end of the upper bell mouth 32 so that the suction port 3a of the lower bell mouth 33 is inclined toward the upstream side of the water flow in the suction tank as it approaches the upper part.

[0039] It is preferable that the suction port 3a is perpendicular to the water flow direction. Here, "perpendicular" means that the water flow direction is perpendicular to a vertical plane including a line where an arbitrary horizontal plane and the suction port 3a intersect (hereinafter the same).

[0040] The inclination angle α of the suction port 3a with respect to the horizontal plane is preferably 15 to 75 degrees upward, and more preferably 15 to 45 degrees upward.

[0041] In this embodiment, the portion of the pump casing 3 facing the rear wall 101 extends deep. Therefore, vortexes from the rear wall 101 are less likely to be sucked in through the suction port 3a. Also, at least the rear wall 101 side of the portion of the pump casing 3 facing the side wall 102 extends deep. Therefore, vortexes from the side wall 102 are less likely to be sucked in through the suction port 3a.

[0042] In this way, the pump 100 can suppress the intake of vortexes, improving the reliability of the pump 100. In addition, there is no need to take measures against vortexes in the civil engineering structure of the suction tank, which is advantageous in terms of construction costs. Furthermore, there is no need to provide additional members around the pump casing 3, so there are no particular restrictions on the opening dimensions of the pump 100.

[0043] The pump 100 may be installed in a single bed or in a two or more beds. The thrust force may be borne by the pump, the motor, or the reducer. The submerged bearing supporting the main shaft 1 may be of a non-water-injection type. Modifications of the pump 100 will now be described.

[0044] 2 is a schematic side view of a pump 100 according to a first modified example. In this pump 100, one or more projections and recesses are provided on the end face of the suction port 3a. The projections and recesses may be wavy, semicircular, or triangular.

[0045] By providing the end face of the suction port 3a with irregularities, the water flow being sucked in can be disturbed. As a result, mixing of the water flow that is the main cause of vortex generation with the surrounding water flow is promoted, making it difficult for vortexes to be sucked in through the suction port 3a of the pump 100. Therefore, air suction vortexes and bottom vortexes can be suppressed.

[0046] 3A to 3C are schematic side views of a pump 100 according to a second modified example. The pump 100 has one or more louvers 4 (inlet vanes) provided on the end face of the suction port 3a. There is no limit to the number of louvers 4, but the number of louvers 4 may be appropriately designed in consideration of the inflow handled liquid.

[0047] Also, it is desirable to install the louvers 4 so that they are parallel to the direction of the water flow. In other words, the direction in which the louvers 4 extend is parallel to the direction of the water flow. The direction of the water flow can be determined, for example, from the results of numerical analysis. For example, in FIG. 3A, the water flows in at an angle close to vertical, so the installation angle of the louvers 4 is also close to vertical. On the other hand, in FIG. 3C, the water flows in at an angle close to horizontal, so the installation angle of the louvers 4 is also close to horizontal.

[0048] By providing the louver 4 on the end face of the suction port 3a, the water flow sucked in near the louver 4 can be disturbed. As a result, air suction vortexes and bottom vortexes can be suppressed. In addition, the efficiency of the pump 100 is improved because the rectified water flows into the bell mouth 32 and the lift pipe 31.

[0049] 4 is a schematic side view of a pump 100 according to a third modified example. The pump 100 includes one or more louvers 5. The louvers 5 extend from the inside of the pump casing 3 (for example, the lower bell mouth 33) to at least the end face of the suction port 3a, and may extend below the most upstream portion of the pump casing 3. The louvers 5 are preferably arc-shaped in cross section.

[0050] The bottom vortex can be further suppressed by providing the louvers 5 that extend from the inside of the pump casing 3 to the suction port 3a. In addition, the louvers 5 extend in a curved shape, so that the water flows into the bell mouth 32 and the lift pipe 31 with the flow straightened, thereby improving the efficiency of the pump 100.

[0051] Figures 5A to 5C are a schematic side view, a schematic perspective view, and a schematic bottom view, respectively, of a pump 100 according to a fourth modified example. The pump casing 3 in this pump 100 has a lifting pipe 31 and an upper bellmouth 32 similar to those in Figures 1A to 1C, and an anti-vortex member 34. The anti-vortex member 34 extends downward from the lower end of the upper bellmouth 32. The anti-vortex member 34 has a shape obtained by cutting a vertically extending rectangular parallelepiped obliquely so that a suction port 3a is formed that is inclined toward the upstream side of the water flow in the suction tank as it approaches the upper part.

[0052] In detail, as shown in FIG. 5B, the vortex countermeasure member 34 has an upper surface 341, a side surface 342, and a rear surface 343. The upper surface 341 is in a horizontal plane and is rectangular. The upper surface 341 is attached to the upper bellmouth 32 with bolts. The side surface 342 extends vertically downward from the upper surface 341 and is parallel to the direction of the water flow. The side surface 342 is triangular and extends deeper downstream (closer to the rear wall 101 of the suction sump). The rear surface 343 extends vertically downward from the upper surface 341 and is perpendicular to the direction of the water flow. The rear surface 343 faces the rear wall 101 of the suction sump.

[0053] The upper surface 341 is rectangular, and as a rectangular obstacle is provided in contrast to the circular bellmouth shape which is prone to generating air-sucking vortices, air-sucking vortices can be suppressed. Also, the side surface 342 extends deeper downstream, so air-sucking vortices from the rear wall side and underwater vortices from the rear wall 101 and side wall (not shown) can be suppressed. The opening area of ​​the suction port 3a is also increased, which slows down the water flow speed and further suppresses the generation of vortices.

[0054] Fig. 6A is a schematic side view of pump 100 according to a fifth modified example. This pump is a column-type submersible pump. Fig. 7A is a schematic side view of pump 100 according to a sixth modified example. This pump is a column-type land pump. Note that the column-type land pump can also be applied to the column shape of a pull-out type (full pull-out or rotor pull-out) pump.

[0055] These pumps 100 include a cylindrical column 30 as the pump casing 3. The column 30 is supported by a pump base 11 and penetrates a pump opening 12. The lower part of the column 30 forms a suction port 3a. This suction port 3a is inclined toward the upstream side of the water flow in the suction tank as it approaches the upper part. A distance p between the part of the column 30 closest to the rear wall 101 and the bottom surface 104 of the suction tank is shorter than a distance q between the part of the column 30 farthest from the rear wall 101 and the bottom surface 104 of the suction tank. As an example, p = 0.3D to 1D, and q = 0.5D to 1D (where D is the diameter of the discharge port of the pump casing to which the discharge piping is connected (see Figures 6A and 7A)).

[0056] Note that the column 30 may be supported by a support stand 13 provided on the bottom surface 104 as shown in FIGS. 6B and 7B, instead of the pump base 11 shown in FIGS. 6A and 7A.

[0057] The portion of column 30 facing rear wall 101 extends deep. Therefore, vortexes from rear wall 101 are less likely to be sucked in through suction port 3a. Also, at least the rear wall 101 side of the portion of column 30 facing side wall 102 extends deep. Therefore, vortexes from side wall 102 are less likely to be sucked in through suction port 3a. This makes it possible to suppress pump 100 from sucking in vortexes.

[0058] Second embodiment The second embodiment relates to a pumping station in which a plurality of pumps 100 described in the first embodiment are installed. The pumps 100 described in the second and subsequent embodiments may be any of those described in the first embodiment. The following description will focus on the differences from the first embodiment.

[0059] Fig. 8 is a schematic diagram of a pumping station according to the second embodiment, viewed from above. In this pumping station, a plurality of pumps 100a-100c (three pumps are illustrated in Fig. 2) are installed. As an example, the pumps 100a-100c are arranged side by side on a straight line perpendicular to the water flow (a straight line parallel to the rear wall 101, or a straight line perpendicular to the side wall 102). It is assumed that no partition wall is provided between each of the pumps 100a-100c and the adjacent pump.

[0060] This pumping station is structured such that water flows into a suction sump through a narrow passage 200. In detail, the narrow passage 200 is connected to a side wall 102 of the suction sump through an inclined wall surface 103.

[0061] Here, the inclined wall surface 103 is inclined in the direction in which the water flow spreads, and no partition wall is provided. Therefore, in the flow path 200, the water flows in the illustrated direction F (a direction perpendicular to the rear wall 101 and parallel to the side wall 102), but when the water flows into the suction tank, the water flow spreads toward the side wall 102. As a result, the direction in which the water flows into the pumps 100a to 100c is not uniform.

[0062] Therefore, in this embodiment, each of the pumps 100a to 100c is disposed so that its suction port 3a is perpendicular to the direction in which water flows in. For example, water flows into the pump 100a in the illustrated direction Fa. Therefore, the pump 100a is disposed so that its suction port 3a is perpendicular to the illustrated direction Fa. The pump 100b is the center of the pumps 100a to 100c, so water flows in the illustrated direction Fb (=F). Therefore, the pump 100b is disposed so that its suction port 3a is perpendicular to the illustrated direction Fb (=F). The pump 100c flows into the pump 100c in the illustrated direction Fc. Therefore, the pump 100c is disposed so that its suction port 3a is perpendicular to the illustrated direction Fc.

[0063] The pump station shown in FIG. 8 is manufactured by arranging a plurality of pumps 100 described in the first embodiment so that their suction ports 3a are perpendicular to the direction in which water flows in.

[0064] In this embodiment, the suction port 3a is inclined as described in the first embodiment. Therefore, even if multiple pumps 100a-100c are installed and water flows into each of them at a non-uniform angle, the intake of vortexes can be suppressed by arranging the pumps 100a-100c in a manner that suppresses the intake of vortexes while taking into consideration interference with the other pumps.

[0065] Third embodiment The third embodiment relates to a pump station in which a plurality of pumps 100 are installed in series. The following will mainly describe the differences from the second embodiment.

[0066] Fig. 9A is a schematic diagram of a pumping station according to the third embodiment, viewed from above. In this pumping station, a plurality of pumps 100d-100f (three pumps are illustrated in Fig. 3) are installed. The pumps 100d-100f are arranged in series with respect to the water flow. Specifically, the pumps 100d-100f are arranged between two opposing side walls 102a, 102b of the suction tank, on a straight line along the direction in which the water flows in (a straight line perpendicular to the rear wall 101, or a straight line parallel to the side walls 102a, 102b). It is assumed that no partition wall is provided between each of the pumps 100d-100f and the adjacent pump.

[0067] The pump 100d disposed at the most upstream position is disposed so that its suction port 3a is perpendicular to the direction in which the water flows (F in the drawing).

[0068] The second pump 100e is arranged so that its suction port 3a faces the side wall 102a and also faces the pump 100d side (upstream side). In other words, the suction port 3a is not perpendicular to the direction in which water flows into the pump 100d (F in the figure). The reason for such an arrangement is that the water flow directly behind the pump 100d moves away from the side of the column, making it easy for Kármán vortices to occur. As the Kármán vortex grows, air-suction vortices are likely to occur upstream of the pump behind it, so the pump 100e is designed to suck in as little water as possible directly behind the pump 100d.

[0069] When further pumps 100 are installed, the third pump 100f is arranged so that its suction port 3a faces the side wall 102b and faces the pump 100d (upstream side). In other words, the suction port 3a is not perpendicular to the direction (F in the figure) in which water flows into the pump 100d. The reason for such an arrangement is that the water flow is away from the side of the column directly behind the pump 100e and Karman vortexes are likely to occur. The Karman vortex grows and air suction vortexes are likely to occur upstream of the pump behind it, so that the pump 100f does not suck in the water directly behind the pump 100e as much as possible. In addition, the suction port 3a of the pump 100f faces a different direction from the suction port 3a of the pump 100e. The reason for such an arrangement is to allow the pump 100f to suck in water flowing in a direction that the pump 100e did not suck in.

[0070] 9A is manufactured by arranging the multiple pumps 100 described in the first embodiment in a straight line between the side walls 102a, 102b of the suction tank along the direction in which water flows in, and arranging the pump 100d arranged at the most upstream position so that its suction port 3a is perpendicular to the direction in which water flows in, and the pump 100e arranged second from the upstream side so that its suction port 3a faces the pump 100d side of the side wall 102a. If there are additional pumps, the pump 100f arranged third from the upstream side is arranged so that its suction port 3a faces the pump 100e side of the side wall 102b.

[0071] In this embodiment, the suction port 3a is inclined as described in the first embodiment. Therefore, even when multiple pumps 100 are arranged in series, it is possible to minimize the intake of water directly behind the upstream pump 100 (i.e., water that is prone to generating vortexes).

[0072] 9B, partition walls 110 extending in the direction in which water flows may be provided between each of pumps 100d-100f and the adjacent pump. Such partition walls 110 may be constructed, for example, by civil engineering work. By providing partition walls 110, a flow field that does not generate an air-suction vortex in pump 100 on the upstream side can be formed, and vortex intake can be further suppressed.

[0073] 10A and 10B are respectively a schematic side view and a schematic top view of a pump 100 suitable for the pump station of FIG. 9. As shown, the pump 100 may have one or more baffle vanes 10. The baffle vanes 10 are fixed to the outer circumferential surface of the pump casing 3 (preferably the lift pipe 31). There are no particular limitations on the fixing position of the baffle vanes 10, and they may be designed appropriately according to the operating water level and the shape of the suction tank.

[0074] The straightening vane 10 is inclined so that it approaches the bottom surface of the suction tank as it approaches the downstream side. The inclination angle β with respect to the horizontal plane is preferably 10 to 50 degrees downward. The horizontal dimension of the straightening vane 10 is preferably equal to or less than the horizontal length of the suction port 3a in the lower bell mouth 33. As shown in FIG. 10B, the straightening vane 10 is annular. However, it may have another shape, such as a rectangle as shown in FIG. 10C.

[0075] Figures 11A to 11C are schematic diagrams of another pump 100 suitable for the pump station of Figure 9, and correspond to Figures 10A to 10C, respectively. As shown in the figures, the baffle vane 10 may be provided only in the upstream half of the pump casing 3 when viewed from above.

[0076] By providing such a straightening plate 10, the water flow (particularly the water flow near the water surface) is guided downward, the flow speed is reduced, and the formation of vortexes is suppressed.

[0077] (Fourth embodiment) The fourth embodiment described next relates to a pumping station in which the pump 100 is arranged in an asymmetric position in the suction sump.

[0078] 12A is a schematic diagram of a pumping station according to a fourth embodiment, viewed from above. As shown in the figure, the pump 100 is disposed at an asymmetrical position in the suction tank. Specifically, the distance from the pump 100 to one side wall 102a is longer than the distance from the pump 100 to the opposing side wall 102b. The pump 100 is disposed so that the suction port 3a is perpendicular to the direction in which water flows in.

[0079] 12B is a schematic diagram of another pumping station according to the fourth embodiment, viewed from above. As shown in the figure, the pump 100 is disposed at an asymmetrical position in the suction tank. Specifically, the distance from the pump 100 to one side wall 102a is longer than the distance from the pump 100 to the opposing side wall 102b. The suction tank is narrow at its upstream portion and wide at its downstream portion. The pump 100 is disposed in the wide portion. The pump 100 is disposed so that the direction in which water flows in is perpendicular to its suction port 3a.

[0080] 12C is a schematic diagram of another pumping station according to the fourth embodiment, viewed from above. As shown in the figure, the pump 100 is disposed at an asymmetrical position in the suction tank. Specifically, the distance from the pump 100 to one side wall 102a is longer than the distance from the pump 100 to the opposing side wall 102b. The suction tank is narrow at the upstream portion and tapers toward the downstream portion. The pump 100 is disposed in the wide portion. The pump 100 is disposed so that the direction in which the water flows in is perpendicular to the suction port 3a.

[0081] The above-described pump station is manufactured by arranging the pump 100 at a position where the distance from the pump 100 to the side wall 102a of the suction tank is different from the distance from the pump 100 to the side wall 102b opposite to the side wall 102a, and by arranging the pump 100 so that its suction port 3a is perpendicular to the direction in which the water flows in.

[0082] In a pumping station where the pump 100 is disposed in an asymmetrical position, drift occurs and vortexes are likely to occur. Even in such a case, by using the pump 100 with an inclined suction port 3a, the intake of vortexes can be suppressed.

[0083] Pump 100 is applicable not only to pumping stations arranged in asymmetrical positions, but also to pumping stations with wide rear walls 101 (for example, the distance between pump 100 and rear wall 101 is 1.5D or more) (Figure 13A), pumping stations where stagnation occurs in the water flow (Figure 13B), pumping stations where there is interference with other pumps (Figures 13C and 13D), and pumping stations where swirling flow occurs (Figures 13E and 13F).

[0084] The inventions described in this specification are not limited to the individual embodiments described above, and various additions, modifications, combinations, and partial deletions are possible as appropriate. For example, what is described in this specification as one device (including what is depicted in the drawings as one device) may be realized by multiple devices. Conversely, what is described in this specification as multiple devices (including what is depicted in the drawings as multiple devices) may be realized by one device. Alternatively, some or all of the means or functions included in one device may be included in another device.

[0085] In addition, parts of one embodiment may be incorporated into other embodiments to the extent that no inconsistency occurs. Furthermore, not all of the features described in this specification are essential. In particular, features described in this specification but not claimed are optional additional features.

[0086] The applicant is merely aware of the inventions disclosed in the documents in the "Prior Art Documents" column of this specification, and each invention described in this specification does not necessarily aim to solve the problems of the inventions disclosed in the documents. The problems that the inventions described in the claims are intended to solve should be identified by considering the entire specification. For example, in this specification, when a specific effect is achieved by a specific configuration (including cases where it is explicitly stated and cases where it can be read from the configuration), it can also be said that the problem that is the reverse of the specific effect is solved. However, it is not necessarily intended that such a specific configuration is an essential requirement. [Explanation of symbols]

[0087] 1 spindle 2 Impeller 3 Pump casing 3a Intake port 30 Column 31 Lift pipe 32 Upper bell mouth 33 Lower bell mouth 34 Vortex protection components 341 Top surface 342 Side 343 Back 4,5 louvers 10 Rectifier plate 11 Pump Base 12 Pump opening 13 Support stand 100,100a~100f pump 101 Back wall 102,102a,102b side wall 103 Inclined Wall 104 Bottom 110 Partition Wall 200 Channels

Claims

1. A pump that pumps water in a suction tank, A main axis extending in a vertical direction; An impeller rotated by the main shaft; a pump casing that houses the impeller therein; A pump, wherein the suction port of the pump casing is inclined toward the upstream side of the water flow in the suction tank as it goes upward.

2. The pump casing comprises: an upper bell mouth located below the impeller and having an open lower end; 2. The pump as described in claim 1, further comprising: a lower bell mouth extending downward from a lower end of the upper bell mouth and having a shape formed by cutting a vertically extending cylinder diagonally so that the suction port is formed such that the suction port is inclined toward the upstream side of the water flow in the suction tank as it approaches the upper part.

3. 3. The pump according to claim 1, wherein the suction port is inclined upward at an angle of 15 to 75 degrees with respect to a horizontal plane.

4. 3. The pump according to claim 1, wherein the suction port is inclined upward at an angle of 15 to 45 degrees with respect to a horizontal plane.

5. The pump according to claim 1 or 2, wherein an end face of the suction port is provided with projections and recesses.

6. The pump according to claim 1 or 2, further comprising a louver provided on an end face of the suction port.

7. The pump according to claim 1 or 2, further comprising a louver extending from an interior of the pump casing to at least an end face of the suction port.

8. The pump casing comprises: an upper bell mouth located below the impeller and having an open lower end; 2. The pump as described in claim 1, further comprising a vortex control member extending downward from the lower end of the upper bell mouth and having a shape formed by cutting a vertically extending rectangular parallelepiped diagonally so that the suction port is formed such that the suction port is inclined toward the upstream side of the water flow in the suction tank as it approaches the upper part.

9. 3. A pump as claimed in claim 1 or 2, wherein the pump casing is a cylindrical column.

10. 3. The pump according to claim 1, further comprising a baffle plate provided on an outer surface of the pump casing and inclined so as to approach a bottom surface of the suction tank as it approaches the downstream side.

11. A main axis extending in a vertical direction; An impeller rotated by the main shaft; an upper bell mouth located below the impeller and having an open lower end; A method for installing a pump having a shape obtained by cutting a vertically extending cylinder obliquely and a lower bell mouth that forms a pump suction port at a lower portion, in a suction tank, comprising the steps of: A method for installing a pump, comprising a step of attaching the lower bell mouth to a lower end of the upper bell mouth so that the suction port is inclined toward the upstream side of the water flow in the suction tank as it approaches the upper part.

12. A pump station in which a plurality of pumps according to claim 1 or 2 are arranged, A pumping station, wherein each of the plurality of pumps is arranged so that its suction port is perpendicular to a direction in which water flows in.

13. The pumping station according to claim 12 , wherein the plurality of pumps are arranged side by side in a straight line perpendicular to a water flow.

14. The pumping station of claim 12 , wherein no partitions are provided between each of the plurality of pumps and adjacent pumps.

15. A method for manufacturing a pumping station, comprising the step of arranging a plurality of pumps according to claim 1 or 2 so that their suction ports are perpendicular to the direction in which water flows in.

16. A pump station in which a plurality of pumps according to claim 1 or 2 are arranged, The plurality of pumps are arranged in a straight line between a first side wall of the suction tank and a second side wall opposite thereto in a direction in which water flows in, The first pump, which is disposed at the most upstream of the plurality of pumps, is disposed so that its suction port is perpendicular to the direction in which water flows in, A pumping station, wherein a second pump that is the second most upstream of the plurality of pumps is positioned so that its suction port faces the first pump side of the first side wall.

17. The pumping station according to claim 16 , wherein a third pump that is arranged third from the upstream side among the plurality of pumps is arranged so that its suction port faces the second pump side of the second side wall.

18. 17. The pumping station of claim 16, wherein there is no partition between each of the plurality of pumps and an adjacent pump.

19. The pumping station according to claim 16 , wherein a partition wall extending along a water flow direction is provided between each of the plurality of pumps and an adjacent pump.

20. A plurality of pumps according to claim 1 or 2 are disposed between a first side wall of a suction tank and a second side wall opposite thereto, They are lined up in a straight line along the direction of the water flow, The first pump, which is disposed at the most upstream of the plurality of pumps, has a suction port perpendicular to the direction in which water flows in, A method for manufacturing a pump station, comprising the step of positioning a second pump, which is the second most upstream of the plurality of pumps, such that its suction port faces the first pump side of the first side wall.

21. A pumping station in which the pump according to claim 1 or 2 is arranged, The pump is disposed at a position where a distance from the pump to a first side wall of the suction tank is different from a distance from the pump to a second side wall opposite to the first side wall, A pumping station, wherein the pump is arranged so that its suction port is perpendicular to the direction in which water flows.

22. The suction tank has a wider downstream section than the upstream section.

22. The pumping station according to claim 21, wherein the pump is arranged in the wide portion.

23. A pump according to claim 1 or 2, A position where a distance from the pump to a first side wall of the suction tank and a distance from the pump to a second side wall opposite to the first side wall are different, A method for manufacturing a pumping station, comprising a step of arranging the suction port so that it is perpendicular to the direction in which water flows.

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