JP2021162008A - Suction packing and pump provided with the same - Google Patents

Abstract

To provide a pump improving maintainability.SOLUTION: A suction packing 40A of a pump 10 has: a rubber seal body part 41 which is mediated between opposed end surfaces of flange connection parts 23, Sj that face each other at a part of a suction port 24 and is in an annular shape put between the opposed end surfaces; an annular protrusion 42 which is formed integrally with the seal body part 41 and protrudes to the side facing the suction port side of the seal body part 41 so that it is positioned between an inner edge step part 25 of the flange connection part 23 and a liner end part 33 with respect to the inner edge step part 25 and the linear end part 33 extending in an axial direction up to a position where it faces the inner edge step part 25 in a radial direction; and a posture holding part 43 which is provided so that it protrudes to an inside of the suction port 24 with respect to an inside end surface of the annular protrusion 42, and is mediated between the outer peripheral surface 33g of the liner end part 33 and an inner peripheral surface 24n of the suction port 24.SELECTED DRAWING: Figure 3

Description

The present invention relates to a pump having a casing having a suction port and a liner built in the casing as a liquid contact portion, and in particular, a flange connection portion of a suction pipe connected to the suction port and a flange connection portion on the pump side. Regarding the suction packing that is interposed between and.

Among the pumps, the pump that transfers the slurry containing a high-concentration solid substance in the liquid has a high frequency of parts replacement because the inner surface of the wetted portion of the casing is worn and corroded by the contact with the slurry. Therefore, by providing a liner in the wetted portion of the casing, running costs are reduced and resources are saved.
More specifically, this type of pump comprises an impeller having a plurality of blades and a casing having a front casing and a back casing. The impeller is housed in a space defined by a front casing and a back casing.
A liner having excellent wear resistance is provided on the inner surface of the casing. This type of liner has a structure in which it is held by a casing surrounding the liner in an assembled state (see, for example, Patent Document 1).

Special Table 2007-533886

Here, since the pump used for this type of application has a liner in the wetted portion, shortening the time for disassembly / assembly work greatly affects maintainability. In particular, as a disassembly / assembly work, a suction packing is interposed between the flange connection portion of the casing provided with the suction port and the flange connection portion of the suction pipe connected to the flange connection portion.
However, in the case of a pump in which the axes are arranged horizontally, the suction packing in the temporarily assisted state is likely to come off during the assembly work and when a plurality of bolts are tightened to fix the flange connections to each other. There is a problem that the position of the suction packing is easily displaced.

Therefore, the present invention has been made by paying attention to such a problem, and in a pump having a liner at the wetted portion of the casing, assembling work between the flange connecting portions of the suction port of the casing and the suction pipe. It is an object of the present invention to provide a suction packing capable of performing the above safely and smoothly and improving maintainability and a pump provided with the suction packing.

In order to solve the above problems, the suction packing according to one aspect of the present invention is provided as a casing having a flange connecting portion provided with a suction port at the center of the cylinder in which the axis is horizontally arranged, and as a wetted portion of the casing. It has a liner to be installed, and a concave annular inner edge step portion is formed at the inner edge end of the flange connection portion of the casing, and the liner tip portion located at the suction port of the liner is the inner edge step. It is used for a pump that extends axially to a position that faces the portion in the radial direction, and is inserted between the flange connection portion of the suction pipe that faces the suction port and is detachably connected to the flange connection portion of the casing. It is a suction packing to be mounted, and is integrally formed with a rubber seal body portion forming an annular shape sandwiched between the end faces of the opposing flange connection portions when they are interposed, and the seal body portion. The annular convex portion protruding from the surface of the seal main body portion facing the suction port side so as to be located between the inner edge step portion and the liner tip portion when the interposition is provided, and the interposition. A posture in which the annular convex portion is provided so as to project from the end surface of the annular convex portion to the downstream side of the suction port and is inserted between the outer peripheral surface of the liner tip and the inner peripheral surface of the suction port of the casing. It is characterized by having a holding portion.

Further, in order to solve the above problems, the pump according to one aspect of the present invention includes a casing having a flange connecting portion provided with a suction port at the center of the cylinder, and a liner installed as a wetted portion of the casing. A pump in which the axis of the flange connecting portion is horizontally arranged, and is interposed between the flange connecting portion of the casing and the flange connecting portion of the suction pipe connected to the flange connecting portion. As the suction packing to be used, the suction packing according to one aspect of the present invention is provided.

According to the present invention, the maintainability of the pump is improved.

It is explanatory drawing of the centrifugal pump which is one Embodiment of the pump which concerns on one aspect of this invention, and the figure shows the cross section along the axis. It is explanatory drawing of the 1st Embodiment of the suction packing which concerns on one aspect of this invention. It is explanatory drawing of the mounting state of the 1st Embodiment of the suction packing which concerns on one aspect of this invention. It is explanatory drawing of the 2nd Embodiment of the suction packing which concerns on one aspect of this invention. It is explanatory drawing of the mounting state of the 2nd Embodiment of the suction packing which concerns on one aspect of this invention. It is explanatory drawing of the mounting state of one Example of the conventional suction packing.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings as appropriate. The pump of the present embodiment includes a casing having a liner at the wetted portion. The drawings are schematic. Therefore, it should be noted that the relationship, ratio, etc. between the thickness and the plane dimension are different from the actual ones, and there are parts where the relationship and ratio of the dimensions are different between the drawings.
In addition, the embodiments shown below exemplify devices and methods for embodying the technical idea of the present invention, and the technical idea of the present invention describes the material, shape, structure, and arrangement of constituent parts. Etc. are not specified in the following embodiments.

As shown in FIG. 1, the pump 10 of the present embodiment includes a housing 4 that rotatably supports a drive shaft 1 in which an axis is horizontally arranged, and a casing 20 mounted on a front end surface of the housing 4. ..
The tip 1s of the drive shaft 1 projects inward from the center of the back surface of the casing 20, and the impeller 2 is cantilevered and supported by the tip 1s of the drive shaft 1. The impeller 2 is housed in the space inside the casing 20.
On the back side of the impeller 2 in the axial direction, a shaft sealing device 3 is arranged between the casing 20 and the housing 4 so as to surround the drive shaft 1. The drive shaft 1 projects rearward from the rear end of the housing 4, and the projecting portion is connected to an output shaft of a motor (not shown) so as to be able to transmit a driving force.

The casing 20 is divided into two at substantially the center along a plane orthogonal to the drive shaft 1, and has a back casing 21 on the back side (right side in the same figure) in the axial direction and a front side (left side in the same figure) in the axial direction. It is configured to have a front casing 22 and the like. A liner 30 is attached to the casing 20 so as to cover the wetted portion on the inner peripheral surface thereof.
A back liner 31 is attached to the back casing 21, and a front liner 32 is attached to the front casing 22. The liners 31 and 32 have a structure in which they are held by casings 21 and 22 surrounding the liners 31 and 32 in an assembled state.

In the example of the present embodiment, the back liner 31 is fixed to the back casing 21 by the back liner fixing screw 31a, and the front liner 32 is fixed to the front casing 22 by the front liner fixing screw 32a.
The front casing 22 and the back casing 21 are detachably fixed around the divided surfaces by using a plurality of bolts and nuts (not shown). A split type liner 30 is provided on the inner surface of the casing 20 as a wetted portion.

In the front casing 22, a suction portion 20s having a suction port 24 formed in the center of the cylinder itself at a position facing the tip 1s of the drive shaft 1 is formed coaxially with the drive shaft 1 and the suction portion 20s. A flange connecting portion 23 is formed around the front end of the suction port 24 so as to project radially in an annular shape.
A concave annular inner edge step portion 25 is formed at the inner edge end of the flange connection portion 23 of the front casing 22. Further, in the front liner 32, the liner tip portion 33 located at the suction port 24 extends axially to a position where the liner tip portion 33 is radially opposed to the inner edge step portion 25 of the flange connecting portion 23.

Here, as shown in FIG. 3, the front end of the suction port 24 of the front casing 22 is connected to the flange connecting portion 23 of the suction portion 20s, and the flange connecting portion Sj of the suction pipe S and the flange of the front casing 22. A substantially annular suction packing 40A is interposed between the facing surfaces of the connecting portion 23. The flange connection portion 23 and the flange connection portion Sj of the suction pipe S are detachably fixed around each other by using a plurality of bolts and nuts (not shown).

As shown in FIGS. 2 and 3, the suction packing 40A of the present embodiment has a rubber seal main body 41, an annular convex portion 42 integrally formed with the seal main body 41, and an annular convex portion 42. It has a posture holding portion 43 that projects from the end surface to the inside of the suction port 24.
The seal main body 41 is an annular portion sandwiched between the flange connecting portion 23 and the end face of the flange connecting portion Sj of the suction pipe S facing the flange connecting portion 23 at the time of interposition. Both sides of the seal main body 41 are the seal surfaces 41a and 41b at the time of interposition.

The annular convex portion 42 is a liner tip portion extending in the axial direction so as to project to a position where the inner peripheral surface of the inner peripheral step portion 25 of the suction port 24 and the inner peripheral surface of the inner edge step portion 25 are radially opposed to each other. Facing the suction port 24 side of the seal main body 41 so as to be located between the inner peripheral surface of the inner edge step portion 25 and the outer peripheral surface 33 g of the liner tip 33 at the time of interposition with respect to the outer peripheral surface of 33. From the surface, it projects in an annular shape toward the suction port 24 side.
The posture holding portion 43 is provided so as to project toward the suction port 24 side from the side end surface of the annular convex portion 42 when intervened, and the outer peripheral surface 33 g of the liner tip portion 33 and the front casing 22. It is configured so that it can be inserted between the inner peripheral surface 24n of the suction port 24.

In the suction packing 40A of the first embodiment, the posture holding portion 43 is formed in a substantially L-shape from a metal plate member formed from a part separate from the seal main body portion 41, and has two upper and lower sides. It is provided in the place.
Each posture holding portion 43 has a substantially L-shaped one side as a base end portion 43b, and the side opposite to the base end portion 43b is an insertion portion 43a extending in the axial direction. The insertion portion 43a is formed to have a size (thickness) that can be inserted between the outer peripheral surface 33g of the liner tip 33 of the front liner 32 and the inner peripheral surface 24n of the suction port 24.
The posture holding portions 43 are separated from each other at two positions facing each other in the radial direction, and the base end portion 43b is fitted on the inner peripheral surface side of the annular convex portion 42 and vulcanized and bonded. As a result, the insertion portion 43a is provided so as to project along the inner peripheral surface of the annular convex portion 42 from the end surface of the annular convex portion 42 to the inside of the suction port 24.

Next, the mounting work and the action and effect of the pump 10 shown in the above embodiment will be described.
In the pump 10 shown in the embodiment, when assembling the flange connecting portion 23 of the suction port 24 on the casing 20 side and the flange connecting portion Sj of the suction pipe S, first, the suction packing 40A is attached to the flange connecting portion 23. The annular convex portion 42 of the above is fitted into the outer peripheral surface of the liner tip portion 33 from the axial direction to be temporarily placed.
Next, in that state, while maintaining the state in which the flange connecting portion Sj of the suction pipe S faces each other, the suction pipe S is detachably fixed using a plurality of bolts and nuts (not shown). As a result, both the sealing surfaces 41a and 41b of the sealing main body 41 are sandwiched, and the necessary sealing function is exhibited. At the time of this assembly work, as described above, in the pump 10 having the liner 30 in the wetted portion, the shortening of the disassembling / assembling work time of the flange connecting portion 23 and Sj with the suction pipe S greatly affects the maintainability.

Here, as shown in a conventional example in FIG. 6, the conventional suction packing 140 includes a rubber seal main body 141 forming an annular shape, an annular convex portion 142 integrally formed with the seal main body 141, and an annular convex portion 142. It is composed of.
When assembling the suction pipe S using the conventional suction packing 140, as shown in the figure, the annular convex portion 142 of the suction packing 140 is fitted into the outer peripheral surface of the liner tip 33 from the front in the axial direction. In this state, the flange connecting portion Sj of the suction pipe S was opposed to each other to perform the assembly work.

However, if the main purpose is to stabilize the temporary placement state of the suction packing 140 at the flange connection portion 23 of the front casing 22, the inner edge step portion 25 of the front casing 22 is shown by a broken line on the upper side of the center line in the figure. However, if the depth L2 is made deeper, the wall thickness M2 of the flange connecting portion 23 becomes thinner by that amount.
Therefore, since there is a high possibility that the flange connecting portion 23 will break from the corner portion of the inner edge step portion 25 due to the strong force acting by fastening the flanges to each other, the depth L2 of the inner edge step portion 25 cannot be increased unnecessarily. Further, if the wall thickness M2 of the flange connecting portion 23 itself is increased, there is a problem that the size of the device becomes large.

On the other hand, focusing on the strength of the flange connecting portion 23 of the front casing 22, if the depth L2 of the inner edge step portion 25 of the front casing 22 is made shallow, the wall thickness M2 of the flange connecting portion 23 can be maintained while keeping the device compact. The thickness of the can also be secured.
However, in this case, as shown on the lower side of the center line in the figure, on the contrary, the axial fitting length between the annular convex portion 142 of the suction packing 140 and the inner edge step portion 25 is shortened. Therefore, there is a problem that the mounting stability in the temporary storage state is lowered and the maintainability at the time of assembling work is lowered.

On the other hand, according to the suction packing 40A of the first embodiment, as shown in FIGS. 2 and 3, the upper and lower posture holding portions 43 are closer to the suction port 24 than the side end surface of the annular convex portion 42. Further, it is overhanging and is formed so as to be insertable between the outer peripheral surface 33g of the liner tip 33 and the inner peripheral surface 24n of the suction port 24 of the front casing 22.
Therefore, as shown in FIG. 3, even if the depth L1 of the inner edge step portion 25 of the front casing 22 is made shallow, the suction packing 40A temporarily placed on the inner edge step portion 25 of the front casing 22 is still in the posture holding portion 43. As a result, the ability to prevent falling off during temporary storage is improved.
Therefore, the pump 10 shown in the above embodiment improves maintainability. Since the depth L1 of the inner edge step portion 25 can be made shallow, the wall thickness M1 of the flange connecting portion 23 can be sufficiently secured while keeping the device compact.

In particular, in the pump 10 according to the present invention, the suction packing 40A of the first embodiment shown in the above embodiment greatly improves the axial assembling property of the liner type pump 10.
As described above, according to the suction packing 40A of the first embodiment, in the temporarily placed state, the posture is set between the outer peripheral surface of the liner tip 33 and the inner peripheral surface of the suction port of the front casing 22 from the front in the axial direction. By fitting the holding portion 43, the temporary placement state of the suction packing 40A can be stabilized.

Therefore, even if the thickness (axial length) of the annular convex portion 42 of the suction packing 40A is reduced, the stability of the temporarily placed state can be improved, so that the depth of the inner edge step portion 25 of the front casing 22 can be improved. It is possible to make L1 shallow, so that the wall thickness M1 of the flange connecting portion 23 can be secured as necessary and sufficient, and the equipment can be kept compact while having the required strength.
Here, when the pump 10 is a small pump, if the opposing gap in the radial direction caused by the amount of eccentricity between the inner surface of the suction port 24 and the outer peripheral surface of the liner of the front liner 32 is narrow or in contact with each other, When the suction packing 40A is temporarily placed on the inner edge step portion 25 of the front casing 22, it is difficult to insert the posture holding portion 43 between the inner peripheral surface 24n of the suction port 24 and the outer peripheral surface 33g of the liner tip portion 33. There is.

On the other hand, in the suction packing 40A of the first embodiment, as described above, the posture holding portion 43 is a metal plate member formed from a part separate from the seal main body portion 41, and faces each other in the radial direction. They are separated from each other at two places, and are fitted into the inner peripheral surface side of the annular convex portion 42 and vulcanized and bonded.
Therefore, when the suction packing 40A is temporarily placed, the radial facing gap between the inner peripheral surface 24n of the suction port 24 and the outer peripheral surface 33g of the liner tip 33 of the front liner 32 is narrow or in contact with each other. The posture holding portion 43 can be easily inserted even when the posture holding portion 43 is in contact with the suction packing 40A, and the posture holding portion 43 can be smoothly inserted from the front in the axial direction to hold the temporary placement posture of the suction packing 40A.

Here, the pump according to the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the gist of the present invention.
For example, in the suction packing 40A of the first embodiment, an example is shown in which the posture holding portion 43 is composed of a metal plate member separate from the seal main body portion 41, but the present invention is not limited to this. 43 may be integrally formed with the seal main body 41.

Hereinafter, an example in which the posture holding portion 43 is integrally formed with the seal main body portion 41 as the suction packing 40B of the second embodiment will be shown. In the second embodiment, the same or corresponding configurations as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted as appropriate.
As shown in FIGS. 4 and 5, the posture holding portion 43 of the suction packing 40B of the second embodiment is formed integrally with the seal main body portion 41 to form an annular shape, and is an inner circumference of the annular convex portion 42. The edge portion on the surface side is provided as a cylindrical shape protruding inside the suction port 24.

Further, in the posture holding portion 43 of the suction packing 40B of the second embodiment, one or a plurality of slits 48 are formed along the axial direction. In the example of the second embodiment, the posture holding portion 43 is separated in the circumferential direction of the overhanging cylindrical shape, and a plurality of slits 48 (in this example, two positions facing each other in the radial direction) are axially separated. It is formed along.
Here, when the pump 10 is a pump having a size larger than that of a medium-sized pump, the facing gap generated by the amount of eccentricity between the inner surface of the suction port 24 and the outer peripheral surface of the liner of the front liner 32 is larger than that of the small pump.

On the other hand, in the suction packing 40B of the second embodiment, the cylindrical posture holding portion 43 is made of rubber integrally formed with the seal main body portion 41, and the edge of the annular convex portion 42 on the inner peripheral surface side. Since the portion is provided so as to project inside the suction port 24 in a cylindrical shape, the rubber posture holding portion 43 is provided so as to fill the facing gap even when the facing gap caused by the eccentricity amount is large. Can be inserted along the axial direction.
At this time, in the front liner 32, the front liner 32 itself is temporarily fixed with the front liner fixing screw 32a shown in FIG. 1 loosened, and the suction packing 40B is fitted in the temporarily fixed state to temporarily place the front liner 32. It is preferable to do so. Then, after the suction packing 40B is temporarily placed, the front liner fixing screw 32a is tightened to finally fix the front liner 32.

As a result, according to the suction packing 40B of the second embodiment, the centering work of the front liner 32 can be performed by the posture holding portion 43 having a cylindrical shape of the suction packing 40B. Therefore, the inner surface of the casing suction port 24 and the outer peripheral surface of the liner of the front liner 32 can be centered together.
Further, according to the suction packing 40B of the second embodiment, the posture holding portion 43 is separated in the circumferential direction of the overhanging cylindrical shape, and a plurality of slits 48 are formed along the axial direction, so that the front liner is formed. It is more suitable for absorbing the variation of the facing gap caused by the eccentricity of 32 and further improving the temporary placement workability.

1 Drive shaft 2 Impeller 3 Shaft sealing device 4 Housing (bearing box)
10 Pump 20 Casing 21 Back casing 22 Front casing 23 Flange connection 24 Suction port 24n Inner peripheral surface of suction port 25 Inner edge step of suction port 30 Liner 31 Back liner 32 Front liner 33 Liner tip 40 Suction packing 41 Seal body 42 Circular convex part 43 Attitude holding part 48 Slit S Suction pipe Sj Flange connection part

Claims (5)

It has a casing having a flange connecting portion provided with a suction port at the center of the cylinder on which the axis is horizontally arranged, and a liner installed as a wetted portion of the casing, and has an inner edge end of the flange connecting portion of the casing. In addition to forming a concave annular inner edge step portion, the liner tip portion located at the suction port of the liner is used for a pump extending axially to a position radially opposed to the inner edge step portion.
A suction packing interposed between a flange connection portion of a suction pipe that is detachably connected to face the suction port and a flange connection portion of the casing.
An annular rubber seal body that is sandwiched between the end faces of the opposing flange connection portions when intervened.
An annular shape that is integrally formed with the seal main body and projects from the surface of the seal main body facing the suction port side so as to be located between the inner edge step portion and the liner tip portion when intervened. With the convex part,
When intervened, it is provided so as to project from the end surface of the annular convex portion to the downstream side of the suction port, and is provided between the outer peripheral surface of the tip of the liner and the inner peripheral surface of the suction port of the casing. The posture holding part to be inserted and
Suction packing characterized by having. The posture holding portion is a metal member formed from a part separate from the seal main body portion, and is fitted to the inner peripheral surface side of the annular convex portion and vulcanized and adhered. The described suction packing. The claim that the posture holding portion is formed integrally with the seal main body portion, and the edge portion on the inner peripheral surface side of the annular convex portion is provided in a cylindrical shape inside the suction port of the casing. The suction packing according to 1. The suction packing according to claim 3, wherein the posture holding portion has a plurality of slits formed along the axial direction, which are arranged apart from each other in the circumferential direction of the overhanging cylindrical shape. A pump having a casing having a flange connecting portion provided with a suction port at the center of the cylinder and a liner installed as a wetted portion of the casing, in which the axis of the flange connecting portion is horizontally arranged. hand,
The suction packing according to any one of claims 1 to 4 is used as a suction packing interposed between the flange connection portion of the casing and the flange connection portion of the suction pipe connected to the flange connection portion. A pump characterized by being equipped.

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