JP2021102990A - mechanical seal - Google Patents

Abstract

To provide a cartridge type mechanical seal that is applicable to all of rotating apparatuses having the same shaft diameter of revolving shafts even if their models and makers are different.SOLUTION: A seal case 13 has a toric plate-like first case part 131 of a maximum diameter, and a cylindrical second case part 132 forming a second diameter and concentrically extending therefrom. A mounting plate 4 having a through hole 41 which fits with the second case part 132 can be attached to the shaft seal part casing 1 with the through hole 41 being fitted to the second case part 132 and the first case part 131 abutting on an edge face 1b of a shaft seal part casing 1 of a rotating apparatus.SELECTED DRAWING: Figure 1

Description

The present invention relates to a mechanical seal, particularly a cartridge type mechanical seal that can be incorporated into and removed from a rotating device extremely easily.

In the conventional cartridge type mechanical seal, as disclosed in Patent Document 1, the rotation including the static side sealing element including the seal case and the static sealing ring attached to the seal case, the sleeve and the rotary sealing ring attached to the sleeve, and the like. It consists of a side sealing element and a connecting means for temporarily connecting both sealing elements to the same form as the usage form, and the both sealing elements are incorporated into the rotating device while being connected to the same form as the usage form by the connecting means. And it is designed to be removed from rotating equipment.

Japanese Unexamined Patent Publication No. 2005-048818

However, since the seal case is directly attached to the casing of the shaft seal of the rotating device, even if the shaft diameter of the rotating shaft is the same, the seal case cannot be attached to the casing of the shaft seal if the model or manufacturer is different. Things happen. Therefore, even if both sealing elements are prepared in a state of being connected to the same form as the usage form by the connecting means, it is difficult to apply them to all rotating devices having the same shaft diameter as they are.

That is, even if a cartridge-type mechanical seal that can be easily incorporated into or removed from the rotating device is prepared, it is necessary to replace the seal case. In this case, reassembly is required, and there is a risk of causing an assembly error each time.

The present invention has been made in view of these points, and an object of the present invention is to provide a mechanical seal that can be applied to a rotating device having the same rotating shaft diameter even if the model and the manufacturer are different.

The mechanical seal that solves this problem is a seal case having an annular first case portion and a cylindrical second case portion that extends concentrically from the first case portion and has a diameter smaller than that of the first case portion. And a mounting plate having a through hole for fitting into the second case portion, the mounting plate fits the through hole into the second case portion, and the first case portion is a shaft of a rotating device. It is attached to the shaft sealing casing in a state of being in contact with the end face of the sealing casing.

In a preferred embodiment of such a mechanical seal, an O-ring is interposed between the first case portion and the shaft sealing portion casing. Further, an engaging bolt that prevents the rotation of the static sealing ring is fitted into the second case portion with its head positioned on the second case portion, and is inserted into the through hole of the mounting plate. Is formed with a notch in which the head of the engaging bolt is locked.

In the mechanical seal according to the present invention, even if the model and the manufacturer are different, it can be applied to a rotating device having the same rotating shaft diameter only by exchanging the mounting plate.

It is sectional drawing which shows an example of the mechanical seal which concerns on this invention. FIG. 5 is a cross-sectional view of the mechanical seal showing a cross section different from that of FIG. 1 (the cross section is along the line II-II of FIG. 3). It is sectional drawing which follows the line III-III of FIG. FIG. 3 is a cross-sectional view corresponding to FIG. 1 showing a state in which the mechanical seal is incorporated into a rotating device. It is sectional drawing corresponding to FIG. 1 which shows the modification of the mechanical seal which concerns on this invention. FIG. 5 is a cross-sectional view of the mechanical seal corresponding to FIG. 2 showing a cross section different from that of FIG.

A mode for carrying out the present invention will be specifically described with reference to the drawings.

As shown in FIGS. 1 and 2, the cartridge type mechanical seal as an example of the mechanical seal penetrates the shaft sealing portion casing 1 of the rotating equipment (process pump, blower, compressor, turbine, stirrer, etc.) and the shaft sealing portion casing 1 thereof. It is incorporated between the rotating shaft 2 and the rotating shaft 2 protruding outside the device. The mechanical seal is an end face contact type configured to partition between the in-flight fluid region A, which is an internal region of the rotating equipment, and the external atmosphere region B, which is an external region of the rotating equipment.

In this cartridge type mechanical seal, the rotating side sealing element 3 attached to the rotating shaft 2, the stationary side sealing element 5 attached to the shaft sealing portion casing 1 by the mounting plate 4, and both sealing elements 3 and 5 are mechanically sealed. It is provided with a connecting means 6 for temporarily connecting to the same mode as the usage mode (the mode in the operating state shown in FIGS. 1 and 2). In this example, the fluid in the in-flight fluid region A (sealed fluid) is a positive pressure liquid.

As shown in FIGS. 1 and 2, the shaft sealing portion casing 1 has a circular through hole 1a, and the rotating shaft 2 penetrates the through hole 1a concentrically with the through hole 1a. From the shaft sealing portion casing 1, bolts (two threaded rods) 7 and 7 project parallel to the rotating shaft 2 from the end surface 1b on the outside air region B side. The bolts 7 and 7 are provided symmetrically with the through hole 1a interposed therebetween.

As shown in FIGS. 1 and 2, the rotating side sealing element 3 includes a sleeve 8 fitted to the rotating shaft 2, a rotating sealing ring 9 attached to the sleeve 8, a stopper ring 10, and the like.

The sleeve 8 has a rotating shaft 2 in a state where the thin-walled cylindrical base end portion 81 is positioned on the outside air region B side and the thick-walled cylindrical tip portion 82 is positioned in the through hole 1a of the shaft sealing portion casing 1. Is fitted to. The sleeve 8 is formed on the base end portion 81 of the sleeve 8 by screwing a plurality of (only one shown) first screws 10a tightened to the sleeve 8 into the stopper ring 10 fitted to the base end portion 81. It is fixed to the rotating shaft 2 by screwing a plurality of (only one) second screw 10b tightened to the rotating shaft 2 through the through hole 83.

The rotary sealing ring 9 is fitted to the tip end portion 82 of the sleeve 8 and is fixed to the tip end portion 82 of the sleeve 8 via an O-ring 11a, a drive pin 11b, and a sheet material 11c.

As shown in FIGS. 1 and 2, the stationary sealing element 5 includes a sealing case 13, a static sealing ring 14 held by the sealing case 13, a spring 15, and the like.

The seal case 13 has a ring plate-shaped first case portion 131 having the maximum diameter in the stationary side sealing element 5, and a second size concentrically extending from an intermediate portion of the first case portion 131 in the outside air region B direction. It includes a cylindrical second case portion 132 having a diameter of an annulus, and an O-ring holding portion 134 having an L-shaped cross section provided on the inner peripheral portion of the first case 131. A spring retainer 133 is fitted to the inner peripheral portion of the second case portion 132 of the seal case 13.

The end surface of the first case portion 131 is an annular surface 131a that can be in close contact with the end surface 1b of the shaft sealing portion casing 1, and the O-ring 16 is loaded on the annular surface 131a. The second case portion 132 is integrally molded with the first case portion 131. The outer diameter of the second case portion 132 is the diameter of the second size, which is smaller than the outer diameter of the first case portion 131, but is larger than the outer diameter of other members constituting the seal case 13 and the spring retainer 133. It is large in comparison.

The O-ring holding portion 134 extends along the inner peripheral surface of the first case portion 131 and has a diameter smaller than the inner diameter of the second case portion 132. The O-ring holding portion 134 is composed of a receiving surface 134a slightly protruding from the annular surface 131a of the first case portion 131 and a movement blocking surface 134b extending inward from the base end portion thereof, and is integrally formed with the first case portion 131. Has been done. The receiving surface 134a is in contact with the through hole 1a of the shaft sealing portion casing 1. The end of the spring retainer 133 is located slightly away from the stopper ring 10, and an annular convex portion 133a is integrally formed.

The static sealing ring 14 includes a sealing ring holding body 141 having a large diameter at the tip portion (the end portion on the in-machine fluid region A side), and a sealing ring main body 142 attached to the tip end portion of the sealing ring holding body 141.

The intermediate portion of the sealing ring holder 141 is held by the O-ring holding portion 134 of the seal case 13 via the O-ring 17 so as to be movable in the axial direction. A notch 141a is formed at the base end of the sealing ring holder 141. An engaging bolt 18 passes through the first case body 131 in the radial direction and is screwed into the second case body 132 in the notch portion 141a. The base end pin portion 181 of the engaging bolt 18 is screwed into the notch portion 141a to prevent the static sealing ring 14 from rotating relative to the seal case 13. The head (tip portion) 182 of the engaging bolt 18 is tightened in contact with the outer peripheral surface of the second case portion 132. That is, the head 182 of the engaging bolt 18 protrudes radially outward from the outer peripheral surface of the second case portion 132.

The spring 15 is loaded between the spring receiving plate 19 held by the sealing ring holder 141 and the spring retainer 133, and is axially oriented so as to bring the sealing ring main body 142 of the static sealing ring 14 into contact with the rotary sealing ring 9. Is attached to. The spring receiving plate 19 is located at a step portion formed on the sealing ring holder 141, and is locked by the urging force of the spring 15.

As shown in FIGS. 2 and 3, the connecting means 6 connects both the sealing elements 3 and 5 in the same state as in the used state during storage, transportation, and installation of the rotating device.

That is, the connecting means 6 has an engaging body 61 having a concave portion that engages with the annular convex portion 133a formed on the spring retainer 133 and a convex portion that engages with the gap between the spring retainer 133 and the stopper ring 10, and the engaging body 61. It is composed of a bolt 62 for fixing the stopper ring 10 to the stopper ring 10 from the upper surface. The connecting means 6 connects the stopper ring 10 and the spring retainer 133 (seal case 13).
Further, as shown in FIG. 3, the connecting means 6 are provided at three places at equal intervals in the circumferential direction.

The head portion 62a of the bolt 62 attached to the stopper ring 10 is set to be slightly higher than the outer diameter of the second case portion 132 of the seal case 13. Further, the outer diameter of the stopper ring 10 is set to be smaller than the inner diameter of the second case portion 132 of the seal case 13, and the head portion 62a of the bolt 62 is set to be smaller than the outer diameter of the first case portion 131 of the seal case 13.

Thus, as shown in FIGS. 1 and 2, in the cartridge type mechanical seal, the seal case 13 of the stationary side sealing element 5 is attached to the shaft sealing portion casing 1 by the mounting plate 4.

The mounting plate 4 has a plate-like shape having a circular through hole 41 formed in the central portion, and an elongated hole 42 for passing the bolt 7 is formed at each end portion. The through hole 41 is formed to match the outer diameter of the second case portion 132 of the seal case 13, and is set to a diameter that can be fitted to the second case portion 132. Notches 43 and 44 are formed in the through holes 41 of the mounting plate 4. The cutouts 43 and 44 are the head 182 of the engaging bolt 18 protruding to the outer peripheral portion of the second case portion 132 of the seal case 13, and the bolts of the connecting means 6 protruding to the outer peripheral side from the outer diameter of the second case portion 132. The head 62a of 62 passes through.

Therefore, according to the mounting plate 4, both sealing elements 3 and 5 are taken out from the storage place in a state of being connected by the connecting means 6, transported to the rotating device, and inserted into the rotating shaft 2 of the rotating device as shown in FIG. By doing so, it can be attached to the shaft sealing portion casing 1 of the rotating device.

That is, as shown in FIG. 4, both sealing elements 3 and 5 are inserted through the rotating shaft 2. At this time, the second screw 10b of the stopper ring 10 is not tightened to the rotating shaft 2, and both sealing elements 3 and 5 are easily inserted into the rotating shaft 2. At this time, the annular collar 21 corresponding to the thickness of the first case portion 131 of the seal case 13 is passed through each bolt 7. Then, the annular surface 131a of the first case portion 131 of the seal case 13 is brought into contact with the end surface 1b of the shaft sealing portion casing 1. Then, the through hole 41 is inserted into the second case portion 132 of the seal case 13 with the O-ring 16 interposed between the end surface 1b and the annular surface 131a. After that, the bolt 7 is inserted into each elongated hole 42, and the nut 20 is screwed into each bolt 7. As shown in FIGS. 1 and 2, by tightening each nut 20, the mounting plate 4 is fixed to the shaft sealing casing 1 in a state of being pressed against the first case portion 131. Further, the mounting plate 4 engages the notch 43 with the head 182 of the engaging bolt 18 by passing the head 62a of each bolt 62 of the connecting means 6 through the notch 44 and then rotating the mounting plate 4 by a predetermined angle. ..

When the seal case 13 is attached to the shaft sealing portion casing 1 by the mounting plate 4, the second screw 10b of the stopper ring 10 is finally tightened to fix the stopper ring 10 to the rotating shaft 2. At this time, the head 182 of the engaging bolt 8 is caught in the notch 42 of the mounting plate 4. As a result, the stationary side sealing element 5 prevents the rotating device from rotating relative to the shaft sealing portion casing 1.

As described above, according to the mounting plate 4, both sealing elements 3 and 5 are connected by the connecting means 6 in the same state as in the used state, and the shaft sealing portion casing 1 is passed through management, transportation, and insertion into the rotating shaft 2. Since it is attached to, it is not necessary to change both sealing elements 3 and 5 including the sealing case 13.

Therefore, if the shaft diameter of the rotating shaft 2 is the same, even if the model and the manufacturer are different, it is possible to correspond to all rotating devices simply by changing the mounting plate 4 to a shape suitable for the shaft sealing portion casing 1. .. Moreover, since it is not necessary to change the seal case 13, as long as the shaft diameter of the rotating shaft 2 is the same even if the model or manufacturer is different, both sealing elements 3 and 5 are not obliged to be changed, and the seal case is not required to be changed. There is no assembly error due to disassembly and reassembly due to the change of 13.

5 and 6 show a modified example of the mechanical seal. As shown in FIG. 5, the mechanical seal of this modified example is a type of bolt 70 in which the means for attaching to the shaft sealing portion casing 1 is screwed into a shaft sealing case such as a threaded bolt or a hexagon bolt instead of the threaded rod 7. .. Further, the color 21 does not necessarily have to be provided. Since the configurations other than the bolt 70 are the same as those shown in FIGS. 1 to 4, they are designated by the same reference numerals and the description thereof is omitted.

Further, as shown in FIGS. 5 and 6, even if the through hole 1a of the shaft sealing portion casing 1 is large and the receiving surface 134a of the seal case 13 does not come into contact with the through hole 1a, there is no problem in terms of the sealing function. Does not occur.

Further, as shown in FIG. 6, when the head 182 of the engaging bolt 18 does not protrude from the upper surface of the second case portion 132 of the seal case 13 and is embedded in the second case portion 132, the mounting portion 4 The frictional engagement force between the seal case 13 and the first case portion 131 and the second case portion 132 prevents the seal case 13 from rotating relative to the shaft sealing portion casing 1.

As described above, in the mechanical seal of the present invention, by preparing various mounting plates 4, when the shaft diameters of the rotating shafts 2 are the same, both sealing elements 3 and 5 are not changed. It can be applied to all rotating devices of different models and manufacturers.

1 Shaft sealing casing 4 Mounting plate 13 Seal case 14 Static sealing ring 16 O-ring 18 Engagement bolt 41 Through hole 43 Notch 131 First case part 132 Second case part 182 Head

Claims (3)

A seal case having an annular first case portion and a cylindrical second case portion extending concentrically from the first case portion and having a diameter smaller than that of the first case portion.
A mounting plate having a through hole for fitting to the second case portion is provided.
A mechanical seal to be attached to the shaft sealing portion casing in a state where the mounting plate fits the through hole into the second case portion and the first case portion is in contact with the end surface of the shaft sealing portion casing of the rotating device. The mechanical seal according to claim 1, wherein an O-ring is interposed between the first case portion and the shaft sealing portion casing. An engaging bolt that prevents the rotation of the static sealing ring is fitted into the second case portion with its head positioned on the second case portion, and the through hole of the mounting plate is said to be the same. The mechanical seal according to claim 1 or 2, wherein a notch for locking the head of the engaging bolt is formed.

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