JP3062845B2 - Rotary shaft sealing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary shaft sealing device provided through a wall of a pressure vessel having a pressure difference between inside and outside.

[0002]

2. Description of the Related Art An example of a conventional rotary shaft sealing device will be described with reference to FIG. Reference numeral 100 denotes a part of the bottom wall of a pressure vessel (not shown). The upper part of the bottom wall 100 is inside the pressure vessel, and the lower part is the atmosphere side. Fluid is supplied with a predetermined pressure into the pressure vessel. The fluid includes, for example, a gas such as air or gas, a liquid such as water or oil, or a powder applied with a predetermined pressure by a gas. A through hole is formed in the bottom wall 100, and a seal case 102 is inserted and fixed through the through hole. The seal case 102 has a cylindrical portion and a mounting flange portion, and a support hole is formed in a central portion thereof. The rotating shaft 104 is arranged to extend over the inside and outside of the bottom wall 100 via the support hole of the seal case 102.
The first sealing means 106 is held in the support hole of the seal case 102. The first sealing means 106 is arranged so as to cover the periphery of the rotating shaft 104.

A first seal retainer 108 is attached to the seal case 102 so that its axial position can be adjusted. The first seal retainer 108 has a cylindrical portion and a mounting flange portion, and a through hole is formed in a central portion thereof. The cylindrical portion of the first seal retainer 108 is positioned in an annular gap between the support hole of the seal case 102 and the rotating shaft 104, and the upper end thereof defines the lower end position of the first sealing means 106. . The upper end position of the first sealing means 106 is defined by a positioning flange formed at the upper end of the support hole of the seal case 102. The second sealing means 110 is held in a support hole located on the lower end side of the through hole of the first seal retainer 108. The second sealing means 110 includes the rotating shaft 1
04 is arranged to cover the periphery.

A second seal holder 112 is attached to the first seal holder 108 so as to be freely adjustable in the axial direction. The second seal retainer 112 has a cylindrical portion and a mounting flange portion, and a through hole is formed at the center thereof. The upper end of the cylindrical portion of the second seal retainer 112 is connected to the support hole of the first seal retainer 108 and the rotating shaft 10.
4, the upper end of which defines the lower end position of the second sealing means 110. The upper end position of the second seal means 110 is defined by a positioning flange formed at the upper end position of the support hole of the first seal retainer 108.

[0005] Lubricating grease is supplied to an annular gap 114 between the center of the through hole of the first seal retainer 108 and the rotating shaft 104. The grease is supplied from a grease supply source (not shown) via a grease supply passage 116 formed in the seal case 102.

The first sealing means 106 includes three identical V-shaped mold packings 116. The V-shaped mold packings 116 are arranged such that their V-shaped open sides face the pressure vessel direction. An end ring 118 is disposed at an upper end position of the first sealing means 106, and a part of the lower end portion thereof contacts the V-shaped opening side of the V-shaped mold packing 116 located at the uppermost portion, and the upper end portion is formed. It is configured to contact the positioning flange of the seal case 102. On the other hand, the second sealing means 110
It includes four identical V-shaped mold packings 120. The V-shaped mold packings 120 are arranged such that their V-shaped open sides face the pressure vessel direction. An end ring 122 is disposed at an upper end position of the second sealing means 110, and a part of a lower end portion thereof contacts a V-shaped opening side of a V-shaped mold packing 120 located at an uppermost position, and an upper end portion is formed. It is configured to contact the positioning flange of the first seal retainer 108. Each V-shaped mold packing 116 and 120, each end ring 118 and 12
In this example, 2 is made of Teflon (trade name) mixed with glass fiber.

[0007] The sealing action of the conventional sealing device constructed as described above will be described with reference to the first sealing means 106 as an example. Referring to FIGS. 3 and 4, first sealing means 1
At 06, an axial force is applied by the first seal retainer 108. Thus, each V-shaped mold packing 116
Of the rotating shaft 104 is pressed and sealed against the outer peripheral surface of the rotating shaft 104. On the other hand, due to the pressure of the fluid from the pressure vessel side, the lip of the V-shaped mold packing 116 is pushed and spread radially inward and outward, and the lip on the inner diameter side is
The seal is pressed against the outer peripheral surface of the rotating shaft 104.

[0008]

The above-described conventional rotary shaft sealing device has the above-described configuration and operation.
It has the following problems to be solved. (1) If the lip of the V-shaped mold packing 116 or 120 is worn during operation, the thickness (thickness in the radial direction) of the packing becomes thin, so the first seal retainer 108 is used.
Alternatively, retightening must be performed with the second seal retainer 112. However, it is extremely difficult to properly set the force for retightening. Also, from the state where retightening is required, until the retightening work is performed, since the sealing performance is in a reduced state,
Since the gas, liquid, powder, or the like on the high pressure side (pressure vessel side) enters the seal portion, the rotary shaft 104 and the seal (each V-shaped packing) may be damaged. In particular,
If powders are mixed, they will be worn in a short time. (2) The lip of the V-shaped mold packing 116 or 120 is expanded by the pressure of the fluid on the pressure vessel side,
The sealing is performed by being pressed against the rotating shaft 104. However, when the pressure on the pressure vessel side decreases and the pressure difference between the bottom wall 100 and the bottom wall 100 (inside and outside the pressure vessel) disappears, the pressure of the fluid causes the V-shaped mold packing 116 or 120 to move.
The force for spreading the lip is lost (see FIG. 5). Therefore, as described in (1) above, gas, liquid, powder or the like on the high pressure side (pressure vessel side) enters the seal portion, so that the rotating shaft 104 and the seal (each V-shaped mold packing) are attached. May be damaged. In particular, when powders are mixed, they are worn in a short time.

Accordingly, a primary object of the present invention is to provide an improved rotating mechanism capable of maintaining a predetermined sealing function despite abrasion of the lip of the V-shaped mold packing or a decrease in pressure on the high pressure side during operation. It is to provide a shaft sealing device.

Another object of the present invention is to provide an embodiment of a rotary shaft sealing device constructed according to the present invention.
It will become apparent from the following description, which is described in detail with reference to the accompanying drawings.

[0011]

According to the present invention, there is provided a pressure vessel having an internal pressure of P1.
A seal case fixed to the wall of the
A rotating shaft provided so as to penetrate the wall, and the rotating shaft
Is held in place in the seal case to cover the periphery of
Sealing means, wherein the sealing means is at least
First sealing means including one V-shaped mold packing
And a second including at least one V-shaped mold packing.
The first sealing means and the second sealing means.
Sealing means are arranged at predetermined intervals in the axial direction.
And a V-shaped mold packing of the first sealing means and the V-shaped mold packing.
The V-shaped mold packing of the sealing means 2 is a V-shaped release
The first sealing means are arranged axially facing each other;
In the space provided between the first sealing means and the second sealing means.
Is supplied with a fluid having a pressure P2 and the pressures P1 and P2
2 is set so as to have a relationship of P1 ≦ P2, the first sealing means and the second sealing means are held in a support hole provided in the seal case, and the first sealing means The distance between the first seal means and the second seal means is defined by a lantern ring disposed between the first seal means and the second seal means, and an inner diameter of the lantern ring and the rotation shaft Gaps are formed between the outer diameter of the lantern ring and the inner diameter of the support hole of the seal case, respectively, and the pressure of the fluid supplied to the lantern ring portion is A rotary shaft sealing device is provided which is configured to act on the first sealing means and the second sealing means through each of the gaps.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a rotary shaft sealing device constructed according to the present invention will be described below in detail with reference to the accompanying drawings. Referring to FIG. 1, a rotary shaft sealing device, generally designated by reference numeral 2, has an internal pressure P <b> 1, a seal case 6 fixed to a wall 4 of a pressure vessel (not shown), and a seal case 6. Shaft 8 provided to penetrate wall 4
A first sealing means 10 and a second sealing means 12 held in the seal case 6 so as to cover the periphery of the rotating shaft 8.
And a seal holder 14 attached to the seal case 6 and defining one end position of the seal unit in the axial direction.

The wall 4 is a part of the bottom wall of the pressure vessel. The upper part of the wall 4 is inside the pressure vessel, and the lower part is the atmosphere side. Fluid is supplied into the pressure vessel at a predetermined pressure P1. This fluid is as described above in the description of the conventional example. In this example, the lower part of the wall 4 is on the atmosphere side, but the wall 4 may be a partition wall that partitions the inside of the pressure vessel. In that case, the pressure in the upper chamber of the partition wall is set higher than the pressure in the lower chamber. A through hole is formed in the wall 4, and the seal case 6 is inserted and fixed through the through hole. The seal case 6 has a cylindrical portion and a mounting flange portion, and a support hole is formed in a central portion thereof. The rotating shaft 8 is arranged to extend over the inside and outside of the wall 4 via the support hole of the seal case 6. The rotating shaft 8 is rotatably supported by a support means (not shown) located below the seal case 6 and is connected to a drive source (not shown). In the support hole of the seal case 6, a first seal means 10 and a second seal means 12 are held at predetermined intervals in the axial direction. These sealing means are arranged so as to cover the periphery of the rotating shaft 8.

The first sealing means 10 has at least one
The second sealing means 12 includes at least one, in this example, three V-shaped packings 18, in this example three V-shaped packings 16. Each V-shaped mold packing 16 and 18 is substantially identical. V-shaped mold packing 1 of first sealing means 10
6 and the V-shaped mold packing 18 of the second sealing means 12
Means that the V-shaped open side faces the axial direction. Positioning flange 2 is provided at the upper end of seal case 6.
0 is formed to extend inward in the radial direction. The one end position of the seal means, that is, the upper end position of the first seal means 10 is defined by the flange 20, and the lower end position of the seal means, that is, the lower end position of the second seal means 12,
It is defined by the end of the seal retainer 14. That is, the seal holder 14 has a cylindrical portion and a mounting flange portion, and the cylindrical portion is inserted into an annular gap between the through hole of the seal case 6 and the rotating shaft 8. The end of the cylindrical portion defines the lower end position of the second sealing means 12. The seal holder 14 is attached to the seal case 6 so that the axial position thereof can be adjusted.

At the upper end of the first sealing means 10, an end ring 22 is arranged. The end ring 22 is formed of Teflon (trade name), and both ends in the axial direction are flat surfaces orthogonal to the axis. End rings 22 and 24 are arranged at axially opposed ends of the first sealing means 10 and the second sealing means 12, respectively. A flat surface in which one end (upper end) in the axial direction of the end ring 22 is configured to be in contact with the V-shaped open side of the V-shaped mold packing 16 and the other end (lower end) is orthogonal to the axial direction. It consists of. End ring 24
A part of one end (lower end) in the axial direction is configured to contact the V-shaped open side of the V-shaped mold packing 18 and the other end (upper end) is formed by a flat surface orthogonal to the axial direction. I have. The V-shaped mold packings 16 and 18 and the end rings 22 and 24 are made of Teflon (trade name) mixed with glass fiber.

Referring to FIG. 2 together with FIG. 1, a lantern ring 26 is disposed between the end rings 22 and 24. First sealing means 10 and second sealing means 12
Is defined by the lantern ring 26. The lantern ring 26 is formed of, for example, gunmetal, stainless steel, or the like. Gaps are formed between the inner diameter of the lantern ring 26 and the outer diameter of the rotating shaft 8 and between the outer diameter of the lantern ring 26 and the inner diameter of the support hole of the seal case 6, respectively. The space formed by the lantern ring 26 is supplied with a fluid having a pressure P2. The pressure of the fluid supplied to the lantern ring 26 is
It is configured to act on the first sealing means 10 and the second sealing means 12 through each of the gaps. More specifically, the lantern ring 26 includes a cylindrical portion 28
And ring plate portions 30 and 32 provided orthogonally to both ends of the cylindrical portion 28. Cylindrical part 28
Is formed with a plurality of through holes 34 in its circumferential direction. Between each inner diameter of the ring plate portions 30 and 32 and the outer diameter of the rotating shaft 8 and between each outer diameter of the ring plate portions 30 and 32 and the inner diameter of the support hole of the seal case 6;
Each of the gaps is formed.

A fluid supply passage 36 and a fluid discharge passage 38 are formed in the seal case 6. Fluid supply passage 36
Has one end opening at the space where the lantern ring 26 is located in the support hole of the seal case 6, and the other end is connected to the pressure fluid storage container 42 via the passage 40 from the mounting flange. Grease is stored in the pressure fluid storage container 42. The pressure fluid container 42 is also connected to a pressure source (not shown) via a passage 44 so that high-pressure gas is supplied at a pressure P2. The pressures P1 and P2 are set to have a relationship of P1 ≦ P2. The pressure P1 is the highest pressure in the pressure vessel. One end of the fluid discharge passage 38 is opened at the space where the lantern ring 26 is located in the support hole of the seal case 6, and the other end is connected to the on-off valve 48 via the passage 46 from the mounting flange. . The on-off valve 48 is normally closed.

Therefore, during operation, the pressure fluid storage container 4
The grease in 2 is pressurized by a high-pressure gas having a pressure P2 and supplied to the lantern ring 26. The pressurized grease supplied to the lantern ring 26 acts on the flat surface of each of the end rings 22 and 24 through each of the gaps. The lips of each of the V-shaped mold packings 16 and 18 are spread radially inward and outward,
The lip on the inner diameter side is pressed against the outer peripheral surface of the rotating shaft 8 to seal. Even if the pressure P1 in the pressure vessel decreases,
The lips of each of the V-shaped mold packings 16 and 18 are:
It is pressed at a constant pressure P2. Even if the lips of each of the V-shaped mold packings 16 and 18 are worn down during operation and their thickness is reduced, the lips are spread out in accordance with the wear. The pressurized grease also diffuses around the rotating shaft 8 to lubricate it.

As described above, the present invention has been described in detail based on the embodiments. However, the present invention is not limited to the above embodiments, and various changes or modifications can be made within the scope of the present invention. is there. For example, the fluid supplied to the portion of the lantern ring 26 is pressurized grease in this example, but may be a simple high-pressure fluid, for example, only a high-pressure gas.

[0020]

According to the present invention, the following effects are achieved. (1) In the present invention, the first seal means and the second seal means are arranged at a predetermined interval in the axial direction, and the V-shaped mold packing of the first seal means and the second seal means V-shaped packing is disposed such that the V-shaped opening side faces the axial direction, and the first sealing means and the second sealing means
Pressure P2 within the space provided between
And the pressures P1 and P2 are such that P1 ≦
It is configured to have a relationship of P2. Therefore,
During operation, even when the lip of the V-shaped mold packing is worn and its thickness is reduced, the lip of the V-shaped mold packing is automatically pushed out according to the degree of wear by the action of the pressure P2, Can reliably retain the sealing function. (2) Further, according to the configuration of the present invention described above, even if the pressure on the high pressure side decreases during operation, regardless of this, the lip of the V-shaped mold packing is expanded by the action of the pressure P2. A predetermined sealing function can be reliably maintained. (3) As a result of the above (1) and (2), intrusion of gas, liquid, powder or the like on the high-pressure side into the seal portion can be reliably prevented, and the life of the seal such as a V-shaped mold packing can be extended. It can be dramatically longer. (4) When the fluid supplied in the space provided between the first sealing means and the second sealing means is grease pressurized with the pressure P2, the grease also has a lubricating function. As a result, high functions can be obtained at low cost, and the practical value thereof is significantly improved. (5) When the space provided between the first sealing means and the second sealing means is defined by a lantern ring, the space can be reduced at a low cost by an extremely simple structure. Can be obtained stably.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a rotary shaft sealing device constructed according to the present invention.

FIG. 2 is a partially cutaway perspective view showing a lantern ring and an end ring included in the rotary shaft sealing device shown in FIG. 1;

FIG. 3 is a sectional view showing an embodiment of a conventional rotary shaft sealing device.

FIG. 4 is a model diagram for explaining a sealing operation of the rotary shaft sealing device shown in FIG. 3;

FIG. 5 is a model diagram showing another operation mode of FIG. 4;

[Explanation of symbols]

 2 Sealing device for rotating shaft 4 Wall 6 Seal case 8 Rotating shaft 10 First sealing means 12 Second sealing means 14 Seal retainer 16 V-shaped mold packing 18 V-shaped molding packing 22 End ring 24 End ring 26 Lantern ring 42 Pressure fluid storage container

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Sho 63-4488 (JP, U) Japanese Utility Model Sho 61-184189 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16J 15/46-15/54 F16J 15/24

Claims (2)

(57) [Claims] (1)Fixed to the wall of the pressure vessel with internal pressure P1
A fixed seal case and the wall through the seal case.
A rotating shaft provided to penetrate the
The seal held at a predetermined position in the seal case to cover
And means The sealing means includes at least one V-shaped mold pack.
First sealing means including a component, and at least one V-shaped module.
And second sealing means including a mold packing. The first sealing means and the second sealing means are in an axial direction.
Are arranged at predetermined intervals, The V-shaped mold packing of the first sealing means and the second mold packing;
The V-shaped mold packing of the sealing means means that the V-shaped open side is
Are arranged facing each other in the axial direction, Provided between the first sealing means and the second sealing means
Fluid having a pressure P2 is supplied within the interval.
And The pressures P1 and P2 have a relationship of P1 ≦ P2.
Is set,  The first sealing means and the second sealing means
Between the first sealing means and the second sealing means.
A gap is provided between the first sealing means and the second sealing means.
And between the inner diameter of the lantern ring and the outer diameter of the rotating shaft.
The outside diameter of the lantern ring and the inside of the support hole of the seal case
A gap is formed between the fluid and the diameter, and the pressure of the fluid supplied to the lantern ring portion is
The first seal means and the second seal via each between
And a rotating shaft sealing device. 2. A V-shaped opening of a V-shaped mold packing at a part of one end in the axial direction of each of ends of the first sealing means and the second sealing means facing each other in the axial direction. An end ring is arranged to be in contact with the side and the other end side is constituted by a flat surface orthogonal to the axial direction, and the lantern ring is arranged between the flat surfaces in each of the end rings. The lantern ring is defined by a cylindrical portion, and a ring plate portion provided at right angles to both ends of the cylindrical portion, and the cylindrical portion has a plurality of through holes in a circumferential direction thereof. The clearance is formed between each inner diameter of the ring plate portion and the outer diameter of the rotating shaft, and between each outer diameter of the ring plate portion and the inner diameter of the support hole of the seal case. Formed and provided to the lantern ring part. Pressure of the fluid, the rotation shaft seal apparatus according to claim 1, characterized in that it is configured to act on the flat surface of each of said end ring through each of the gap.