JP2017014984A - Fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid machine in which split casings are combined to constitute a casing, which secures seal function without an increase in the size of a flange constituting mating faces of the split casings.SOLUTION: The fluid machine includes a lower casing 21 and an upper casing 22. A pump 1 where the lower casing 21 and the upper casing 22 are combined to constitute the casing 2 includes clamp members 51, 52 for clamping flanges 211F, 212F of the lower casing 21 and flanges 221F, 222F of the upper casing 22 while the lower casing 21 and the upper casing 22 are combined at respective flanges.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a fluid machine such as a pump, and more particularly to a fluid machine in which a casing is divided into divided casings, and the divided casings are combined with each other to form the casing.

  A fluid circulates inside the casing of the fluid machine. For example, in a pump that handles a liquid, the liquid sucked from the suction port gives pressure and kinetic energy to the liquid by the centrifugal force of the impeller and the lift force of the blade, and is discharged from the discharge port, whereby the liquid circulates inside the casing. In general, a pump has a structure in which parts in a casing such as a shaft seal and an impeller need regular maintenance, and thus the casing can be divided and maintenance can be easily performed.

  7 is a perspective view of a conventional double-axis suction centrifugal pump, FIG. 8 is a left side view of FIG. 7, FIG. 9 is a front view of FIG. 7, and FIG. FIG. 11 is a cross-sectional view taken along the line BB of FIG. As shown in FIGS. 7 to 11, the casing 110 constituting the outer shape of the horizontal-axis double suction centrifugal pump 100 is composed of a plurality of divided casings. Specifically, the casing 110 has a structure in which the casing 110 is divided into two horizontally on a plane including the rotation axis and is divided into a lower casing 111 and an upper casing 112.

  During the operation of the pump 100, the casing is pressurized by the liquid pressurized by the impeller, so that the lower casing 111 and the upper casing 112 have flanges 111F and 112F formed on their mating surfaces. , 112F are firmly joined by fastening them with the casing bolt 120. By bringing the lower casing 111 and the upper casing 112 into close contact with each other, the inside of the casing 110 is sealed, and the liquid flowing through the casing 110 is prevented from leaking from between the lower casing 111 and the upper casing 112. The

JP 2014-134162 A

  In order to ensure the sealing function even when the liquid inside the casing becomes high pressure, it is necessary to increase the surface pressure of the mating surfaces of the divided casings. For this purpose, it is necessary to fasten the flanges of the divided casings with a large fastening force using large casing bolts.

  A plurality of casing bolts need to be arranged at regular intervals on the flange. Moreover, the operation | work which fastens a some casing bolt to a flange is an operation | work which needs adjustment, seeing the tightening degree of each casing bolt. Therefore, as the number of casing bolts increases, the fastening operation becomes more difficult in combination with the processing accuracy of the casing bolt hole of the flange, and the fastening becomes more difficult unless it is a skilled engineer.

  Further, when the casing bolt is enlarged, the flange constituting the mating surface corresponding to such a large casing bolt has a large area and a sufficient thickness (with sufficient strength to withstand the strong fastening force of the casing bolt). For example, it is necessary to design so that it may have about 80-100 mm. As a result, there is a problem that the casing is increased in size and weight. Furthermore, there may be a case where such a large area and thick flange cannot be provided due to the structure of the fluid machine.

  In a pump using a special carrier liquid having high corrosivity such as seawater, it is necessary to use an expensive material having high corrosion resistance such as duplex stainless steel for a casing in contact with the carrier liquid. In this case, since the flange portion is molded integrally with the casing, an expensive material is used for the flange portion that does not come into contact with the carrier liquid, resulting in an increase in cost.

  The present invention has been made in view of the above-described problems, and is a fluid machine in which a split casing is combined to form a casing, and the casing does not increase the size of the flange that forms the mating surfaces of the split casing. An object of the present invention is to provide a fluid machine that ensures the prevention of mouth cracking.

  A fluid machine according to an aspect of the present invention is a fluid machine including a first divided casing and a second divided casing, and the first divided casing and the second divided casing are combined to form a casing. A clamp member sandwiching the flange of the first divided casing and the flange of the second divided casing in a state where the first divided casing and the second divided casing are combined with each other by the flanges; It has the composition provided.

  With this configuration, the clamp member sandwiches the flange of the first divided casing and the flange of the second divided casing, so that the first divided casing and the second divided casing are brought into close contact with and fixed by the flanges. Therefore, it is not necessary to fasten the flanges with the casing bolts, and the flanges can be reduced in size and thickness, thereby reducing the weight of the fluid machine. Moreover, the installation work of a casing can be simplified by reducing a casing bolt. Furthermore, since the divided casing is fixed by the clamp member, the divided casing is not easily broken even if the internal pressure of the fluid machine increases.

  In the fluid machine, the clamp member may be fixed to the flange of the first divided casing and the flange of the second divided casing with a bolt.

  With this configuration, the clamp member can be reliably fixed to the flange of the first split casing and the flange of the second split casing. Even if the number of bolts for fixing the flanges is smaller than the number of casing bolts for directly fixing the flanges in a conventional fluid machine, the sealing function is not impaired thereby.

  The fluid machine may be a pump including a rotating shaft and an impeller fixed to the rotating shaft and rotated by rotation of the rotating shaft, and the first divided casing and the second divided casing. May be divided with the rotation axis as a boundary.

  With this configuration, when the casing of the pump is divided, the sealing function between the divided casings can be ensured without increasing the size and weight of the casing even if the liquid in the casing becomes high pressure.

  In the above fluid machine, the clamp member may be divided with the rotating shaft as a boundary.

  With this configuration, the divided casing can be sealed on both the suction side and the discharge side of the pump.

  According to the present invention, the clamp member sandwiches the flange of the first split casing and the flange of the second split casing so that the first split casing and the second split casing are brought into close contact with each other by the flanges. Since they are fixed, it is not necessary to fasten the flanges with casing bolts, and the flanges can be reduced in size and thickness, thereby reducing the weight of the fluid machine.

1 is an exploded perspective view of a horizontal-axis double suction centrifugal pump according to an embodiment of the present invention. The left view of the horizontal-axis double suction centrifugal pump of embodiment of this invention The front view of the horizontal-axis double suction vortex pump of embodiment of this invention AA cross section of horizontal suction pump of the horizontal axis of the embodiment of the present invention BB sectional drawing of a horizontal-axis double suction centrifugal pump of an embodiment of the invention The top view of the clamp member of the horizontal-axis double suction vortex pump of embodiment of this invention Perspective view of a conventional horizontal suction pump Left side view of a conventional horizontal suction pump Front view of a conventional horizontal suction pump CC cross section of a conventional horizontal suction pump DD cross section of a conventional horizontal suction pump

  Embodiments of the present invention will be described below with reference to the drawings. The embodiment described below shows an example when the present invention is implemented, and the present invention is not limited to the specific configuration described below. In carrying out the present invention, a specific configuration according to the embodiment may be adopted as appropriate. In the following embodiments, a horizontal-bore double suction centrifugal pump will be described as a fluid machine. However, the present invention is not limited to a liquid pump as long as it is a fluid machine configured by dividing a casing.

  1 is an exploded perspective view of a horizontal-axis double suction centrifugal pump (hereinafter simply referred to as “pump”) according to an embodiment of the present invention, FIG. 2 is a left side view of FIG. 1, and FIG. 1 is a front view of FIG. 1, FIG. 4 is a cross-sectional view taken along line AA in FIG. 2, and FIG. 5 is a cross-sectional view taken along line BB in FIG. FIG. 6 is a plan view of the discharge side clamp member and the suction side clamp.

  As shown in FIGS. 1 to 5, the pump 1 is configured by accommodating an impeller 4 fixed to a rotary shaft 3 in a pump casing 2. The suction casing 202 is wound in a spiral shape after the fluid flowing in from one suction port 23 is separated into two by the volute casing 201 inside the suction casing 202, and the inlets 24 provided on both sides of the volute casing 201, 24 (see FIG. 4) flows into the volute casing 201, and the fluid pressurized by the rotation of the impeller 4 is discharged from the discharge port 25.

  The pump casing 2 is composed of a plurality of divided casings. Specifically, the pump casing 2 includes a lower casing 21 below the rotating shaft 3 and an upper casing 22 above the rotating shaft 3. That is, the pump casing 2 is divided horizontally with the rotary shaft 3 as a boundary, and is divided into upper and lower divided casings (a lower casing 21 and an upper casing 22). The lower casing 21 and the upper casing 22 correspond to the divided casing of the present invention.

  The lower casing 21 and the upper casing 22 have flanges on their mating surfaces. Specifically, the lower casing 21 has a lower suction side flange 211F formed on the suction side with respect to the rotation shaft 3 and a lower discharge side flange 212F formed on the discharge side with respect to the rotation shaft 3. The upper casing 22 has an upper suction side flange 221F formed on the suction side with respect to the rotary shaft 3 and combined with a lower suction side flange 211F, and a lower discharge side flange 212F formed on the discharge side with respect to the rotary shaft 3. And 222F to be combined.

  The lower suction side flange 211F and the lower discharge side flange 212F are respectively formed along the outer periphery of the upper end of the lower casing 21, and the upper suction side flange 221F and the upper discharge side flange 222F are respectively along the outer periphery of the lower end of the upper casing 22. Is formed. The lower suction side flange 211F and the upper suction side flange 221F are formed to protrude from the upper end of the lower casing 21 and the lower end of the upper casing 22 toward the suction side, respectively. The lower discharge side flange 212F and the upper discharge side flange 222F is formed to protrude from the upper end of the lower casing 21 and the lower end of the upper casing 22 toward the discharge side. The lower casing 21 and the upper casing 22 are in close contact with each other on the flange surface.

  Bolt holes 211FH are formed at both ends of the lower suction side flange 211F, bolt holes 212FH are formed at both ends of the lower discharge side flange 212F, and both ends of the upper suction side flange 221F correspond to the bolt holes 211FH. Bolt holes 221FH are formed, and bolt holes 222FH corresponding to the bolt holes 212FH are formed at both ends of the flange 222F on the upper discharge side.

  The pump 1 has a clamp member that sandwiches the flange of the lower casing 21 and the flange of the upper casing 22 in a state where the lower casing 21 and the upper casing 22 are combined with each other. Specifically, the suction side clamp member 51 sandwiches the lower suction side flange 211F and the upper suction side flange 221F that are aligned with each other, and the discharge side clamp member 52 includes the lower discharge side flange 212F and the upper discharge that are aligned with each other. The side flange 222F is sandwiched.

  The suction side clamp member 51 has a U-shaped cross section so that the lower suction side flange 211F is supported from the lower side, the upper suction side flange 221F is pressed from the upper side, and is fitted from the suction side. Yes. The discharge-side clamp member 52 has a U-shaped cross section so that the lower discharge-side flange 212F is supported from the lower side, the upper discharge-side flange 222F is pressed from the upper side, and is fitted from the discharge side. Yes.

  Bolt holes 51H corresponding to bolt holes 211FH and 221FH are formed at both ends of the suction side clamp member 51, and the discharge side clamp member 52 also corresponds to bolt holes 212FH and 222FH at both ends thereof. A bolt hole 52H is formed.

  When the suction-side clamp member 51 is fitted to the lower suction-side flange 211F and the upper suction-side flange 221F that are aligned with each other, the bolt hole 51H, the bolt hole 211FH, and the bolt hole 221FH are aligned. The clamp member fixing bolt 511 is screwed into the bolt hole 51H, the bolt hole 211FH, and the bolt hole 221FH, and the suction side clamp member 51 is fixed to the pump casing 2. Further, when the discharge-side clamp member 52 is fitted to the lower discharge-side flange 212F and the upper discharge-side flange 222F that are aligned with each other, the bolt hole 52H, the bolt hole 212FH, and the bolt hole 222FH coincide. The clamp member fixing bolt 512 is screwed into the bolt hole 52H, the bolt hole 212FH, and the bolt hole 222FH, and the discharge side clamp member 52 is fixed to the pump casing 2.

  The suction side clamp member 51 and the discharge side clamp member 52 are made of fiber reinforced plastic (FRP: Fiber Reinforced Plastics). The suction-side clamp member 51 and the discharge-side clamp member 52 may be bonded to the lower casing 21 and the upper casing 22 or are simply in contact with each other at a position in contact with the lower casing 21 and the upper casing 22 (the flange thereof). Just be fine.

  As described above, in the pump 1 of the present embodiment, the mating surface of the lower casing 21 and the upper casing 22 is used as a flange, and the flange of the lower casing 21 and the flange of the upper casing 22 are sandwiched between the clamp members, The casing 21 and the upper casing 22 can be fixed and sealed.

  Compared with the conventional pump 100 of FIGS. 7 to 11, in the pump 1 of the present embodiment, it is not necessary to first provide a casing bolt for fastening the flanges together. That is, in the conventional pump 100, as shown in FIG. 7, the flanges are brought into close contact with each other with a plurality of casing bolts. However, in the pump 1 of the present embodiment, the clamp members are fixed to both ends of each flange. Only a clamp member fixing bolt is provided. This is because the suction side clamp member 51 and the discharge side clamp member 52 are responsible for sealing the lower casing 21 and the upper casing 22 so as to withstand the internal pressure in the pump casing 2, so that a plurality of conventional casing bolts are provided. This is because there is no need to provide a clamp member fixing bolt 511 for fixing the suction side clamp member 51 to the pump casing 2 so that the suction side clamp member 51 does not simply come off to the suction side. Similarly, a conventional casing bolt is unnecessary on the discharge side, and a clamp member that fixes the discharge side clamp member 52 to the pump casing 2 at both ends of the flange so that the discharge side clamp member 52 does not come off to the discharge side. Only the fixing bolt 521 is provided.

  As described above, when the number of bolts is reduced, it is possible to simplify the mounting work for mounting the lower casing 21 and the upper casing 22 to form the pump casing 2.

  Further, in the pump 1 of the present embodiment, the suction side clamp member 51 and the discharge side clamp that sandwich the respective flanges serve to seal the lower casing 21 and the upper casing 22 so as to withstand the internal pressure in the pump casing 2. Since the member 52 bears, it is not necessary to make the flange itself large and thick as compared with the conventional pump 100, and the flanges of the lower casing 21 and the upper casing 22 can be made smaller and thinner. Therefore, according to the pump 1 of this Embodiment, the pump casing 2 can be reduced in weight compared with the past.

  Moreover, since the pump casing 2 can be reduced in size in this way, the material (for example, cast iron, cast steel, steel) of the pump casing 2 can be saved, and the cost can be reduced. In particular, when duplex stainless steel is used as the material of the pump casing 2, duplex stainless steel is expensive. Therefore, the material cost can be greatly reduced by downsizing and thinning the flange.

  In the above embodiment, FRP is used for the suction side clamp member 51 and the discharge side clamp member 52, but the material of the suction side clamp member 51 and the discharge side clamp member 52 is not limited to this. In addition, as a material of the suction side clamp member 51 and the discharge side clamp member 52, the thing with strong tensile strength and a lightweight is desirable.

  In the above embodiment, the suction side clamp member 51 and the discharge side clamp member 52 are formed so as to sandwich the entire flange, respectively, but only a part of the flange may be sandwiched. Further, a plurality of such clamping members may be provided on the suction side and the discharge side. That is, the clamp member may be divided in the axial direction.

  Further, a sealing member such as an O-ring may be provided between the lower suction side flange 211F and the upper suction side flange 221F and between the lower discharge side flange 212F and the upper discharge side flange 222F. Further, in the above embodiment, two bolt holes and clamp member fixing bolts are provided on each of the suction side and the discharge side, but one bolt hole and clamp member fixing bolt are provided on each of the suction side and the discharge side. It may be. Furthermore, the suction side clamp member 51 and the discharge side clamp member 52 may be fixed to the pump casing (flange thereof) by a method other than bolts.

  According to the present invention, the clamp member sandwiches the flange of the first divided casing and the flange of the second divided casing, so that the first divided casing and the second divided casing are brought into close contact with and fixed by the flanges. Therefore, the bolt holes of the flange can be reduced, the flange can be reduced in size and thickness, and the fluid machine can be reduced in weight, thereby providing the first divided casing and the second divided casing. The casing is useful as a fluid machine or the like in which the casing is formed by being combined with each other.

1 Horizontal double suction pump (fluid machine)
2 Pump casing 21 Lower casing (split casing)
211F Lower suction side flange 212F Lower discharge side flange 211FH, 212FH Bolt hole 22 Upper casing (split casing)
221F Upper suction side flange 222F Upper discharge side flange 221FH, 222FH Bolt hole 23 Suction port 24 Inlet 25 Discharge port 3 Rotating shaft 4 Impeller 51 Suction side clamp member 51H Bolt hole 511 Clamp member fixing bolt 52 Discharge side clamp member 52H Bolt Hole 521 Clamp member fixing bolt

Claims (4)

A fluid machine comprising a first divided casing and a second divided casing, wherein the first divided casing and the second divided casing are combined to form a casing;
A clamp member that sandwiches the flange of the first divided casing and the flange of the second divided casing in a state where the first divided casing and the second divided casing are combined with each other by the flanges. A fluid machine characterized by   2. The fluid machine according to claim 1, wherein the clamp member is fixed to a flange of the first divided casing and a flange of the second divided casing with a bolt.   The fluid machine is a pump including a rotating shaft and an impeller fixed to the rotating shaft and rotated by rotation of the rotating shaft, and the first divided casing and the second divided casing are The fluid machine according to claim 1, wherein the fluid machine is divided with a rotation axis as a boundary.   The fluid machine according to claim 3, wherein the clamp member is divided with the rotating shaft as a boundary.

Images