Pump casing

Abstract

To provide a pump casing improved in stability of an installed pump.SOLUTION: A pump casing 18 includes a first pump casing 181, a first suction flow passage portion 201 connected with the first pump casing 181, and a first discharge flow passage portion 221 connected with the first pump casing 181. The pump casing 18 further includes a second pump casing 182, a second suction flow passage portion 202 connected with the second pump casing 182, and a second discharge flow passage portion 222 connected with the second pump casing 182. The pump casing 18 also includes a suction branch portion 24 connected with the first suction flow passage portion 201 and the second suction flow passage portion 202, a discharge confluence portion 26 connected with the first discharge flow passage portion 221 and the second discharge flow passage portion 222, a first leg portion 38 provided in the suction branch portion 24, and a second leg portion 40 provided in the discharge confluence portion 26.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a pump casing. [Background technology]

[0002] Conventionally, pump equipment has been used for various purposes in various houses, factories, and other locations. For example, in-line pumps, in which the pump and motor are integrated and the pump's suction and discharge ports are aligned on the same line, are widely used because they can be easily installed in the middle of piping. When installing in-line pumps in building facilities, it is desirable to avoid liquid transfer being stopped when one in-line pump breaks down or when one is being inspected regularly.

[0003] In the European market, two inline pumps are installed in parallel so that one can back up the other to avoid liquid transfer stoppage. In this case, there is a product called a twin pump, in which two inline pumps are arranged in parallel, one suction port and one discharge port are connected to the two inline pumps, and the two inline pumps share one suction port and one discharge port. In the following, if the two inline pumps do not share one suction port and one discharge port, that is, if the two inline pumps each have one suction port and one discharge port, these pumps are called single pumps.

[0004] By installing twin pumps, if a problem occurs with one of the pumps, the parts other than the casing of the pump with the problem can be removed and the top of the casing can be covered with a closing flange. The parts other than the casing include, for example, the electric motor placed on the top of the casing, the rotating shaft connected to the electric motor, and the impeller fixed to the rotating shaft and housed inside the casing. With twin pumps, operation can be continued using the other pump during the maintenance period of the pump or while waiting for a spare part for the broken pump.

[0005] Space saving and long life are demands for products, and pump manufacturers are developing their own products to meet these demands. In response to this demand, the length of the header pipe for branching or merging the piping to the two single pumps is reduced in the case of a twin pump, compared to the case of installing two single pumps in parallel. Also, space can be saved by sharing valves such as check valves for preventing backflow between the two pumps that make up the twin pump. In this way, twin pump manufacturers can meet the space saving demands from their customers. Also, the pump life can be simply doubled by operating the two pumps that make up the twin pump in alternating operation.

[0006] Regarding pump manufacturing, in the case of a single pump, i.e., when two in-line pumps are installed in parallel, the parts of the pump that come into contact with the floor, such as the bottom of the pump and the bottom of the legs, only need to be machined to make the pump level for each pump. Furthermore, when installing a single pump, the gap between the floor and the pump and the levelness of the pump only need to be adjusted for each pump.

[0007] However, in the case of twin pumps, the pump casings for two pumps are manufactured as a single unit, and so the floor contact parts for two pumps are also manufactured as a single unit. Therefore, the floor contact parts for each pump must be level during manufacturing and installation, and the two pumps must be level with each other during manufacturing and installation. The layout and machining precision of the floor contact parts affect whether the pump can stand on its own when installed, and to what extent noise and vibration can be suppressed during pump operation. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] International Publication No. 2018 / 137019 Summary of the Invention [Problem to be solved by the invention]

[0009] SUMMARY OF THE PRESENT EMBODIMENT One aspect of the present invention has been made to overcome these problems, and has as its object to provide a pump casing which improves the stability of the installed pump. [Means for solving the problem]

[0010] In order to solve the above problems, a first aspect of the present invention provides a pump casing for use in a pump device for transporting a liquid, the pump casing including a first pump casing, a first suction flow path portion connected to the first pump casing, a first discharge flow path portion connected to the first pump casing, a second pump casing, a second suction flow path portion connected to the second pump casing, a second discharge flow path portion connected to the second pump casing, and a suction passage portion connected to the first suction flow path portion and the second suction flow path portion. Including a branch portion, a discharge junction portion that connects the first discharge flow passage portion and the second discharge flow passage portion, and the suction Including The pump casing has a configuration characterized by having a first leg portion provided at the branch portion and a second leg portion provided at the discharge junction portion.

[0011] In this embodiment, Including It has a first leg provided at the branch point and a second leg provided at the discharge junction. Including The stability of the pump casing is increased by providing legs at the branch and discharge junction. This makes it possible to reduce noise and vibration during pump operation more effectively than ever before, providing a pump casing with improved stability for the installed pump.

[0012] In a second embodiment, the pump casing of the first embodiment has a configuration characterized in that at least one of the first leg portion and the second leg portion has a screw hole.

[0013] A third embodiment employs a pump casing configuration according to the first or second embodiment, characterized in that at least one of the first leg portion and the second leg portion has a base portion.

[0014] In a fourth form, the pump casing has a configuration of any one of the first to third forms, characterized in having a third leg portion provided on at least one of the first pump casing and the second pump casing.

[0015] In a fifth form, the pump casing of any one of the first to fourth forms has a configuration characterized by having a fourth leg portion provided in at least one of the first discharge flow path portion and the second discharge flow path portion.

[0016] In a sixth form, the pump casing of any one of the first to fifth forms has a configuration characterized by having a fifth leg portion provided in at least one of the first suction passage portion and the second suction passage portion.

[0017] In a seventh embodiment, a pump device is provided that includes a first electric motor, a first rotating shaft connected to the first electric motor, a first impeller fixed to the first rotating shaft and housed in the first pump casing, a second electric motor, a second rotating shaft connected to the second electric motor, a second impeller fixed to the second rotating shaft and housed in the second pump casing, and a pump casing of any one of the first to sixth embodiments. is being harvested. [Brief description of the drawings]

[0018] [Figure 1] FIG. 2 is a schematic diagram illustrating one embodiment of a pump casing. [Diagram 2] FIG. 2 is a schematic diagram illustrating an embodiment of a first pump device. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the following embodiments, the same or corresponding components are designated by the same reference numerals, and duplicated descriptions may be omitted. Furthermore, the features shown in each embodiment can be applied to other embodiments as long as they are not mutually inconsistent.

[0020] 1 is a schematic diagram showing one embodiment of a pump casing 18 of the present invention. The pump casing 18 is used in a pump device 16 for transporting liquid. One pump casing 18 has a first pump casing 181, a first suction flow passage portion 201 connected to the first pump casing 181, and a first discharge flow passage portion 221 connected to the first pump casing 181. The pump casing 18 further has a second pump casing 182, a second suction flow passage portion 202 connected to the second pump casing 182, and a second discharge flow passage portion 222 connected to the second pump casing 182.

[0021] The pump casing 18 also has a suction branching section 24 connected to the first suction passage section 201 and the second suction passage section 202, and a discharge junction section 26 connected to the first discharge passage section 221 and the second discharge passage section 222. The first pump casing 181, the first suction passage section 201, the first discharge passage section 221, the second pump casing 182, the second suction passage section 202, the second discharge passage section 222, the suction branching section 24, and the discharge junction section 26 are an integrated casting. Note that some of these, for example, the first discharge passage section 221, the second discharge passage section 222, and the discharge junction section 26, may be manufactured as a casting separate from the other parts.

[0022] The suction branching section 24 refers to a section from the suction port 20 to a point where the first suction flow passage section 201 and the second suction flow passage section 202 are branched. Specifically, it refers to a section from the suction port 20 to a start end 58 of the first suction flow passage section 201, and a section from the suction port 20 to a start end 60 of the second suction flow passage section 202. The discharge junction section 26 refers to a section from a point where the first discharge flow passage section 221 and the second discharge flow passage section 222 are joined to the discharge port 22. Specifically, it refers to a section from a terminal end 281 of the first discharge flow passage section 221 to the discharge port 22, and a section from a terminal end 282 of the second discharge flow passage section 222 to the discharge port 22. The suction port 20 of the pump device 16 is a connection section between the pump device 16 and a pipe (not shown) on the suction side of the pump device 16. The discharge port 22 of the pump device 16 is a connection portion between the pump device 16 and a pipe (not shown) on the discharge side of the pump device 16.

[0023] The pump device 16 has a first pump device 161 and a second pump device 162. The first pump device 161 and the second pump device 162 may have the same configuration or different configurations. In this embodiment, the first pump device 161 and the second pump device 162 have substantially the same configuration. That is, the first impeller 51, the first pump casing 181, and the first discharge passage portion 221 have the same dimensions and shapes as the second impeller 52, the second pump casing 182, and the second discharge passage portion 222, respectively. The rotation direction 54 of the first impeller 51 is the same as the rotation direction 56 of the second impeller 52. On the other hand, the first suction passage portion 201 and the second The dimensions and shape of the suction passage portion 202 are slightly different.

[0024] In this embodiment, the first pump device 161 and the second pump device 162 are centrifugal pumps, but the first pump device 161 and the second pump device 162 are not limited to centrifugal pumps and may be non-positive-displacement pumps. In other words, the first pump device 161 and the second pump device 162 may be turbine pumps, axial flow pumps, or mixed flow pumps.

[0025] Since the first pump device 161 and the second pump device 162 have substantially the same configuration, the configuration of the first pump device 161 will be described with reference to Fig. 2. Fig. 2 is a schematic diagram showing one embodiment of the first pump device 161. The first pump device 161 has a first electric motor 101, a first rotating shaft 121 connected to the first electric motor 101, and a first impeller 51 fixed to the first rotating shaft 121 and housed in a first pump casing 181.

[0026] Although not shown, the second pump device 162, like the first pump device 161, has a second electric motor, a second rotating shaft connected to the second electric motor, and a second impeller 52 fixed to the second rotating shaft and housed within the second pump casing 182.

[0027] In the first pump device 161, the first impeller 51 is a centrifugal impeller. The rotating shaft 121 is rotatably supported by a bearing (not shown). The rotating shaft 121 and the first impeller 51 are rotatable together. The rotating shaft 121 and the first impeller 51 are rotated by an electric motor 101. A liner ring 102 is disposed around the fluid inlet 51a of the first impeller 51. The liner ring 102 is fixed to a pump casing 181.

[0028] A casing cover 122 is disposed between the electric motor 101 and the pump casing 181. The opening at the top of the pump casing 181 is closed by the casing cover 122. The electric motor 101 is fixed to the casing cover 122. The pump casing 181 and the casing cover 122 are cast metal. A shaft seal device 15 that seals the gap between the rotating shaft 121 and the casing cover 122 is disposed on the back side of the first impeller 51. The shaft seal device 15 is held by the casing cover 122. An example of the shaft seal device 15 is a mechanical seal. The closing flange (not shown) described above is installed at the position of the casing cover 122 during maintenance and the like. It is attached by using the screw holes 62 (see FIG. 3) that are arranged circumferentially to attach the casing cover 122. The closing flange is disk-shaped and has mounting holes circumferentially at positions corresponding to the screw holes 62 on the outer edge of the closing flange.

[0029] The pump casing 18 includes a suction branch section 24 having a suction port 20 and a discharge junction section 26 having a discharge port 22. The first impeller 51 is disposed in a first pump casing 181. The suction port 20 and the discharge port 22 are aligned in a straight line. The pump device 16 in which the suction port 20 and the discharge port 22 are aligned in a straight line is called an in-line pump device. In this embodiment, two in-line pumps are aligned in parallel, and one suction port and one discharge port are connected to the two in-line pumps, so that the two in-line pumps share one suction port and one discharge port. When the two in-line pumps share one suction port and one discharge port, these pumps as a whole constitute one twin pump. The pump casing 18 includes a first leg 38 provided at the suction branch section 24 and a second leg 40 provided at the discharge junction section 26.

[0030] Here, we will explain the difference between a twin pump, which is one in-line pump, and two in-line pumps (two single pumps) arranged in parallel. In the case of single pumps, the discharge ports of each single pump are connected to a pipe on the discharge side, and then the two pipes merge downstream to form a single pipe. Also, on the suction side, one pipe branches into two pipes, and then each pipe connects to the suction port of each single pump. On the other hand, in a twin pump, two discharge flow paths merge at discharge junction 26 on the discharge side and then connect to a pipe at the discharge port 22 of the twin pump. Also, on the suction side of the twin pump, the pipe connects to the suction port 20 of the pump, and then branches into two suction flow paths via suction branch 24.

[0031] When the electric motor 101 rotates the first impeller 51, the liquid flows from the suction port 20 into the pump casing 18. More specifically, the liquid flows from the suction port 20 into the first suction passage portion 201, and flows into the fluid inlet 51a of the first impeller 51 through the first suction passage portion 201. The rotating first impeller 51 imparts velocity energy to the liquid, and the velocity energy of the liquid flowing through the first pump casing 181 is converted into pressure. The pressurized liquid is discharged from the pump casing 18 through the discharge port 22.

[0032] Various operating methods are possible for the first pump device 161 and the second pump device 162. An operating method in which only one of the first pump device 161 and the second pump device 162 is operated and the other is stopped, or an operating method in which both the first pump device 161 and the second pump device 162 are operated simultaneously are possible. An on-off valve 28 is provided in the discharge junction 26 as shown in Fig. 1. The on-off valve 28 closes the discharge flow passage connected to the stopped pump device depending on the operating states of the first pump device 161 and the second pump device 162.

[0033] For example, when the first pump device 161 is operating and the second pump device 162 is stopped, the on-off valve 28 is moved to position 282 indicated by dotted lines by the water pressure from the first discharge flow path portion 221 to close the second discharge flow path portion 222. When the second pump device 162 is operating and the first pump device 161 is stopped, the on-off valve 28 is moved to position 281 indicated by dotted lines by the water pressure from the second discharge flow path portion 222 to close the first discharge flow path portion 221. When both the first pump device 161 and the second pump device 162 are operating simultaneously, the on-off valve 28 is moved to position 282 indicated by dotted lines by the water pressure from the first discharge flow path portion 221 and the second discharge flow path portion 222 to close the first discharge flow path portion 221. solid line 283.

[0034] 3 to 5 show the structure of the pump casing 18 alone. FIG. 3 is a top view of the pump casing 18. FIG. 4 is a perspective view of the pump casing 18. FIG. 5 is a bottom view of the pump casing 18. FIGS. 3 to 5 show the pump casing 18 in a state where components other than the pump casing 18, i.e., the first electric motor 101, the first rotating shaft 121, the first impeller 51, the second electric motor, the second rotating shaft, the second impeller 52, etc., have been removed from the pump device 16. The suction port 20 is provided in the suction flange 34. The suction flange 34 is for connecting the pump casing 18 to a pipe. The discharge port 22 is provided in the discharge flange 36. The discharge flange 36 is for connecting the pump casing 18 to a pipe.

[0035] As shown in FIG. 5, the pump casing 18 has a first leg 38 provided at the suction branch section 24 and a second leg 40 provided at the discharge junction 26. Conventionally, no legs have been provided at the suction branch section 24 or the discharge junction 26. Conventional legs have been provided at the first pump casing 181 and the second pump casing 182. This is because the bottoms of the first pump casing 181 and the second pump casing 182 are located at the lowest positions in the pump device 16, as shown in FIG. 2.

[0036] It is expected that the first leg 38 and the second leg 40 will reduce vibration and noise of the pump device 16 for the following reasons. When a twin pump is used, the vibrations are always transmitted to the other pump device. Therefore, the installation conditions for suppressing vibration and noise are more difficult than those for a single pump that is not a twin pump. With a single pump, it is necessary to suppress vibration and noise for only one pump device. However, with a twin pump, the vibration and noise situation becomes complicated because of the influence of vibration and noise from the other pump device. The suction branch 24 and the discharge junction 26 are one of the sources of vibration and noise. By adding the first leg 38 and the second leg 40 to the suction branch 24 and the discharge junction 26, the vibration and noise of the pump device 16 can be reduced more than before.

[0037] At least one of the first leg 38 and the second leg 40 shown in Fig. 5 preferably has a threaded hole. In this embodiment, the second leg 40 has a threaded hole 42. The threaded hole 42 has various purposes. One is for installing the pump device 16. Another purpose is to prevent the pump casing 18 from being upside down (the pump casing 18 hanging from the jig) when the pump casing 18 is placed on a processing jig during manufacture.

[0038] At least one of the first leg 38 and the second leg 40 preferably has a base portion. In this embodiment, the second leg 40 has a base portion 44. The base portion 44 may be a flange. The reason for providing the base portion 44 is that the mounting state of the pump device 16 is more stable when the pump device 16 is installed or when the pump casing 18 is manufactured.

[0039] It is preferable to have a third leg provided on at least one of the first pump casing 181 and the second pump casing 182. In this embodiment, as shown in Fig. 5, the first pump casing 181 is provided with two legs 46, and the second pump casing 182 is provided with two legs 48.

[0040] A fourth leg may be provided in at least one of the first discharge passage portion 221 and the second discharge passage portion 222. A fifth leg may be provided in at least one of the first suction passage portion 201 and the second suction passage portion 202.

[0041] Although the above describes examples of the embodiments of the present invention, the above-described embodiments of the present invention are intended to facilitate understanding of the present invention and do not limit the present invention. The present invention may be modified or improved without departing from the spirit thereof, and the present invention naturally includes equivalents thereof. Furthermore, any combination or omission of each component described in the claims and specification is possible within the scope of solving at least a part of the above-mentioned problems or achieving at least a part of the effects. [Explanation of symbols]

[0042] 16...Pump unit 18…Pump casing 20…Suction port 22…Discharge port 24…Suction branch section 26...Discharge merging section 28...Shut-off valve 34...Suction flange 36…Discharge flange 38…First leg 40…Second leg 42…Screw hole 44…Base section 46...legs 48...legs 51…First impeller 52…Second impeller 101...Electric motor 101...First motor 121...Rotation axis 121…First rotation axis 161...First pump device 162...Second pump device 181…Pump casing 181...First pump casing 182...Second pump casing 201...first suction passage portion 202...second suction passage portion 221...first discharge passage portion 222...second discharge flow passage portion

Claims

1. A pump casing for use in a twin pump for transporting liquid, the pump casing having one suction port and one discharge port as a whole, A first pump casing; a first suction passage portion connected to the first pump casing; a first discharge flow passage portion connected to the first pump casing; A second pump casing; a second suction passage portion connected to the second pump casing; a second discharge flow passage portion connected to the second pump casing; an intake branch portion having the intake port and including a start end portion of the first intake passage portion and a start end portion of the second intake passage portion; a discharge junction portion having the discharge port and including a terminal end portion of the first discharge flow path portion and a terminal end portion of the second discharge flow path portion; A first leg provided at the suction branch; and a second leg portion provided at the discharge junction.

2. The pump casing of claim 1 , wherein at least one of the first leg and the second leg includes a threaded hole.

3. 3. The pump casing according to claim 1, wherein at least one of the first leg and the second leg has a base portion.

4. 4. The pump casing according to claim 1, further comprising a third leg provided on at least one of the first pump casing and the second pump casing.

5. At least one of the first discharge flow passage portion and the second discharge flow passage portion is provided with 5. A pump casing according to claim 1, further comprising a fourth leg portion which is formed in a groove.

6. 6. The pump casing according to claim 1, further comprising a fifth leg provided in at least one of the first suction passage portion and the second suction passage portion.

7. A first electric motor; a first rotating shaft coupled to the first electric motor; a first impeller fixed to the first rotating shaft and housed within the first pump casing; A second electric motor; a second rotating shaft connected to the second electric motor; a second impeller fixed to the second rotating shaft and housed within the second pump casing; A twin pump comprising the pump casing according to any one of claims 1 to 6.

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