JP2008002560A - Sealing structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing structure with a seal ring and a backup ring independently exchangeable, for preventing the backup ring from being largely protruded from an annular groove with thermal expansion. <P>SOLUTION: The sealing structure comprises: the annular groove 9 formed on the outer peripheral face of a fitting portion 8 to be detachably fitted into a cylindrical portion of a high-temperature and high-pressure treatment device; the seal ring 1 mounted in opposition to a first side wall face 13 on the high pressure side of the annular groove 9 for sealing; and the resin backup ring 3 mounted in opposition to a second side wall face 14 on the low pressure side of the annular groove 9 for supporting a back face 4 of the seal ring 1. On a supporting face 5 of the backup ring 3 in contact with the back face 4, an annular uprising portion 6 is formed to be swollen to the side of the seal ring 1. Besides, a stepped face 11 is formed on the back face 4 in a mounted and non-compressed condition for engaging with an outer diameter peripheral face 10 of the annular uprising portion 6. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sealing structure for sealing a fluid substance such as a high-pressure gas used in a high-temperature high-pressure processing apparatus.

In a high-temperature and high-pressure treatment device that encloses high-temperature and high-pressure gas or the like (fluid substance), a fluororesin is used to seal the gap (gap) between the high-pressure container enclosing the fluid substance and the lid member for opening and closing. The sealing member which consists of etc. is used.
Specifically, as shown in FIG. 8, the lid member 40 has a fitting portion 43 that is detachably fitted into a cylindrical wall portion 42 in the vicinity of the opening of the high-pressure vessel 41, and the outer peripheral surface of the fitting portion 43. A sealing ring 46 for sealing, in which a metal spring 45 is housed, is fitted in the annular groove 44 formed in the above. Further, a backup ring 47 is mounted in the annular groove 44 to support the seal ring 46 so that it does not protrude to the gap S side (on the low pressure side) between the open cylindrical wall portion 42 and the fitting portion 43 at high pressure.

  After the high-temperature and high-pressure treatment, when the lid member 40 is removed from the high-pressure vessel 41 and opened in a high-temperature state, the backup ring 47 is a large-diameter size fluororesin ring. Therefore, as shown in FIG. It expands in the outer diameter direction and protrudes greatly from the annular groove 44. In this state, it is difficult to fit the lid member 40 again, and there is a problem that the backup ring 47 that protrudes when the lid member 40 is forcibly fitted is sandwiched between the high-pressure vessel 41 and the lid member 40 and is damaged. .

In addition, there is a conventional sealing structure in which a backup ring and a seal ring are bonded, and even if the backup ring is thermally expanded, the seal ring can prevent the backup ring from protruding (for example, Patent Documents). 1).
JP 2006-57834 A

  However, in the conventional seal member in which the backup ring and the seal ring are bonded, if one of the backup ring and the seal ring deteriorates, there is a disadvantage that it must be replaced together even if the other is still usable. there were.

  Therefore, an object of the present invention is to provide a sealing structure in which the backup ring is prevented from greatly protruding from the annular groove due to thermal expansion, and the seal ring and the backup ring can be replaced independently.

  In order to achieve the above object, a sealing structure according to the present invention includes an annular groove formed on an outer peripheral surface of a fitting portion that is detachably fitted in a cylindrical portion of a high-temperature and high-pressure processing apparatus, and the annular groove Sealing seal ring mounted facing the first side wall surface on the high pressure side, and resin made to mount facing the second side wall surface on the low pressure side of the annular groove and supporting the back surface of the seal ring And a back-up ring, and an annular convex bulge bulging to the seal ring side is formed on the receiving surface of the backup ring that comes into contact with the back surface. A stepped surface that engages with the outer peripheral surface portion of the annular convex ridge is formed.

  The seal ring may be formed in a U-shaped cross section having a groove that opens to the first side wall surface side, and may have a metal resilient member in the groove.

  Further, the annular groove formed on the outer peripheral surface of the fitting portion that is detachably fitted in the cylindrical portion of the high-temperature and high-pressure processing apparatus, and the first side wall surface on the high-pressure side of the annular groove are mounted to face each other. In a sealing structure comprising: a sealing ring for sealing; and a resin backup ring mounted opposite to the second side wall surface on the low pressure side of the annular groove and supporting the back surface of the sealing ring. An annular bulge that bulges to the second sidewall surface is formed on the contact surface of the backup ring that contacts the second sidewall surface, and the annular ridge is formed on the second sidewall surface in an uncompressed state. A step surface that engages with the outer peripheral surface portion is formed.

The present invention has the following remarkable effects.
According to the sealing structure according to the present invention, when the fitting portion is pulled out from the cylindrical portion in a high temperature state, the backup ring to be expanded in the outer diameter direction by thermal expansion is provided on the seal ring (or the second side wall surface). Engagement at the step surface can suppress expansion in the outer diameter direction. And it can prevent that a backup ring protrudes greatly from an annular groove. Therefore, when the fitting portion is inserted into the cylindrical portion again in a high temperature state, there is no possibility that the backup ring is sandwiched between the fitting portion and the cylindrical portion and damaged, and the fitting portion is moved into the cylindrical portion. Can be inserted and fitted smoothly.
Furthermore, since the seal ring and the backup ring can be separated, they can be replaced independently. That is, unlike the conventional seal member in which the seal ring and the backup ring are bonded, the service life of one of them is not limited to the other product life that deteriorates quickly, and the use cost is excellent.

Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments.
The present invention relates to a sealing structure that seals a fluid substance such as a high-pressure gas used in a high-temperature and high-pressure treatment apparatus. As shown in FIG. The space (gap) between the outer peripheral surface of the fitting portion 8 that is detachably fitted in the cylindrical portion 7 is sealed. In FIG. 1, the upper side is the outer peripheral side and the lower side is the inner peripheral side, and the alternate long and short dash line indicates the axis of the cylindrical portion 7 and the fitting portion 8.

  In FIG. 1, reference numeral 20 denotes a high-pressure vessel of a high-temperature and high-pressure processing apparatus that encloses a gas or the like (fluid substance) in a high-temperature and high-pressure state. The cylindrical portion 7 is, for example, a cylindrical wall near the opening of the high-pressure vessel 20. Part. Reference numeral 21 denotes a lid member that covers the high-pressure vessel 20, and the lid member 21 has the fitting portion 8 that is fitted into the cylindrical wall portion 7. The fitting portion 8 includes a shaft portion 18 having a circumferential cutout portion 17 at the tip edge, and a disk portion 19 fixed to the tip of the shaft portion 18 with a bolt or the like. That is, on the outer peripheral surface of the fitting portion 8, a circumferential annular groove 9 composed of a notch portion 17 and an outer edge portion of the base end surface of the disk portion 19 is formed.

  A sealing ring 1 for sealing having a U-shaped cross section is disposed in the annular groove 9 so as to face the first side wall surface 13 on the high pressure side (left side in the figure) H of the annular groove 9. In the concave groove 16 opened to the first side wall surface 13 side, a metal elastic member (plate spring) 2 that applies tension in the inner diameter / outer diameter direction is housed. Further, a resin-made backup ring 3 (such as a fluororesin) that supports the back surface 4 of the seal ring 1 is arranged to face the second side wall surface 14 on the low pressure side (right side in the drawing) L of the annular groove 9. It is installed. The seal ring 1 and the backup ring 3 are large-diameter rings having a diameter of, for example, 400 mm to 700 mm. In the illustrated example, the seal ring 1 is made of a fluororesin.

  1 shows a state in which the fitting portion 8 of the lid member 21 is fitted in the cylindrical wall portion 7 of the high-pressure vessel 20, in other words, the seal ring 1 (and the impact) mounted in the annular groove 9. Member 2)-The compressed state in which the backup ring 3 is pressed in the inner diameter direction is shown.

  FIG. 2 shows a state in which the seal ring 1 (and the elastic member 2) and the backup ring 3 are mounted in the annular groove 9 and the fitting portion 8 is not fitted in the cylindrical wall portion 7, in other words, the seal ring 1 (And the elastic member 2) The backup ring 3 is shown in an uncompressed state.

  In FIG. 2, an annular ridge 6 that bulges toward the seal ring 1 is formed on the receiving surface 5 of the backup ring 3 that contacts the back surface 4 of the seal ring 1. Further, a step surface 11 is formed on the back surface 4 of the seal ring 1 so that the step surface 11 and the outer peripheral surface portion 10 of the annular ridge 6 are engaged in the uncompressed state.

The projecting dimension A ₁ of the annular convex ridge 6 is set larger than the movable dimension (gap) B ₁ in which the seal ring 1 and the backup ring 3 can be displaced in the groove width direction within the annular groove 9. When the protruding dimension A ₁ is less than the movable dimension B ₁ , when the fitting part 8 is pulled out and removed from the cylindrical wall part 7 at a high temperature, the locking convex part 22 and the annular convex ridge part 6 come off, This is because the backup ring 3 protrudes greatly from the annular groove 9 due to thermal expansion.

  FIG. 3 is an enlarged view of the compressed state of FIG. 1, and shows a state in which the seal ring 1 and the backup ring 3 are respectively crimped to the inner peripheral surface of the cylindrical wall portion 7 and the bottom surface 24 of the annular groove 9.

4 shows a state where the seal ring 1 and the elastic member 2 are not attached to the annular groove 9, and FIG. 5 shows a state where the backup ring 3 is not attached.
In FIG. 4, the seal ring 1 has a U-shaped seal portion 25 having a concave groove 16 and a substantially rectangular cross section projecting integrally on the outer half (upper half) of the base end surface of the seal portion 25. And a locking projection 22. That is, the step surface 11 is formed on the inner peripheral surface of the locking projection 22.

  Further, a triangular chevron-shaped inner lip portion 26 and an outer lip portion 27 are provided at the tip of the U-shaped seal portion 25. The elastic member 2 having a U-shaped to V-shaped cross section housed in the concave groove 16 is a metal spring such as stainless steel made up of a number of branched small plate spring protrusions or U-shaped bent plate spring pieces. .

  In FIG. 5, the backup ring 3 includes a ring main body 28 having a rectangular cross section and an annular ridge 6 having a substantially rectangular cross section protruding integrally with the inner half (the lower half of the figure) of the front end surface. And have.

  Returning to FIG. 1, a circumferential cutout 29 is formed at the inner peripheral opening edge of the cylindrical wall portion 7. A U-shaped seal 31 is mounted in the notch 29. The U-shaped seal 31 is internally provided with a metal leaf spring 30 that gives tension in the inner and outer diameter directions. Further, tapered guide surfaces 32 and 33 for guiding the seal ring 1, the backup ring 3, and the U-shaped seal 31 are provided in the cylindrical wall portion 7 so that the fitting portion 8 can be smoothly fitted into the cylindrical wall portion 7. It is provided on the peripheral surface and the outer peripheral surface of the fitting portion 8 respectively.

Next, FIG. 6 and FIG. 7 show other embodiments of the sealing structure of the present invention, FIG. 6 shows a non-compressed state, and FIG. 7 shows a compressed state.
In FIG. 6, reference numeral 8 denotes a fitting portion that is detachably fitted to a cylindrical wall portion (tubular portion) 7 (see FIG. 1), and the fitting portion 8 has an annular groove 9 on its outer peripheral surface. . A seal ring 1 having a U-shaped cross section is mounted facing the first side wall surface 13 on the front end side (high-pressure side H) of the annular groove 9, and a metal elastic member 2 is housed in the concave groove 16 of the seal ring 1. ing. Further, a resin-made backup ring 3 is mounted facing the second side wall surface 14 on the base end side (low pressure side L) of the annular groove 9.

  The contact surface 12 of the backup ring 3 that is in contact with the second side wall surface 14 is formed with an annular convex ridge 60 that bulges to the second side wall surface 14, and the second side wall surface in the uncompressed state of FIG. 14 is formed with a step surface 15 that engages with the outer circumferential surface portion 61 of the annular convex ridge 60.

  More specifically, the backup ring 3 includes a ring main body portion 28 having a rectangular cross section and an annular ridge 60 having a rectangular cross section projecting integrally with the inner half (the lower half of FIG. 6) of the base end face. Have. The annular groove 9 has a locking ridge 62 formed by projecting the opening edge on the second side wall surface 14 side toward the first side wall surface 13, and the inner peripheral surface of the locking ridge 62 is The step surface 15 is formed. The back surface 4 of the seal ring 1 and the receiving surface 5 of the backup ring 3 that supports the seal ring 1 are each formed in a flat surface (straight surface).

The projecting dimension A ₂ of the annular convex ridge 60 is set larger than the movable dimension (gap) B ₂ in which the seal ring 1 and the backup ring 3 can be displaced in the groove width direction in the annular groove 9. When the protruding dimension A ₂ is less than or equal to the movable dimension B ₂ , when the fitting portion 8 is pulled out and removed from the cylindrical wall portion 7 in a high temperature state, the locking protrusion 62 and the annular ridge 60 are disengaged. This is because the backup ring 3 protrudes greatly from the annular groove 9 due to thermal expansion.
6 and 7, the same reference numerals as those in FIGS. 1 to 3 have the same configurations as those in FIGS.

  The sealing structure of the present invention can be freely changed in design. For example, in FIG. 2, the surface of the annular convex ridge 6 and the surface of the locking convex 22 are formed in an arc shape (convex curved surface), respectively, and the seal ring The mating surfaces (back surface 4 and receiving surface 5) of 1 and the backup ring 3 may be formed in an S shape.

  Although not shown, the seal ring 1 may not be combined with a metal member (metal bullet member 2) (having a cross-sectional shape other than the U-shaped cross section). That is, the seal ring 1 may be formed of a resin having a small linear expansion coefficient, and has a strength capable of suppressing the expansion in the outer diameter direction due to the thermal expansion of the backup ring 3.

  As the material of the backup ring 3, known materials such as polyacetal, polyamide, and polyetheretherketone can be used in addition to the fluororesin.

Further, in a state in which the fitting portion 8 is pulled out from the cylindrical wall portion 7 in a high temperature state, that is, in an uncompressed state in the high temperature state, the annular convex ridge portion 6 abuts on the locking convex portion 22 and the backup ring 3 is If it can be prevented from protruding from the annular groove 9, there will be a slight gap between the outer circumferential surface portion 10 of the annular convex ridge 6 and the step surface 11 of the locking convex portion 22 in a normal temperature (low temperature) state. It does not matter. This also applies to the relationship between the annular ridge 60 and the locking protrusion 62 shown in FIGS.
Note that the uncompressed state in FIGS. 2 and 6 indicates the uncompressed state in the normal temperature (low temperature) state before the high temperature state.

The use method (action) of the above-described sealing structure of the present invention will be described.
First, as shown in FIG. 2, the fitting portion 8 in which the seal ring 1 in which the backup ring 3 and the resilient member 2 are housed is mounted in the annular groove 9 is inserted into the cylindrical wall portion 7 and covered. At this time, the seal ring 1 is compressed in the inner diameter direction while sliding along the guide surface 32 (see FIG. 1) formed on the inner peripheral surface of the cylindrical wall portion 7. Further, since the annular convex ridge 6 of the backup ring 3 and the engaging convex portion 22 of the seal ring 1 are engaged with each other, the backup ring 3 also moves in the inner diameter direction along with the movement of the seal ring 1 in the inner diameter direction. Move to. Then, the seal ring 1 (and the elastic member 2) and the backup ring 3 are compressed on the inner peripheral surface of the cylindrical wall portion 7 (see FIG. 1 or FIG. 3).

  After the high-temperature and high-pressure treatment in the high-pressure vessel 20 covered as described above, the fitting portion 8 of the lid member 21 is pulled out and removed from the cylindrical wall portion 7 in a high-temperature state (for example, 200 ° C.). The high-temperature backup ring 3 released from the compressed state tries to expand in the outer diameter direction due to thermal expansion, but the annular convex ridge 6 (outer diameter peripheral surface portion 10) and the locking convex portion 22 (step surface 11) Since they are in contact and locked, the seal ring 1 suppresses the expansion of the backup ring 3 in the outer diameter direction and prevents the protrusion from protruding greatly from the annular groove 9.

  In the case of the other embodiments shown in FIGS. 6 and 7, after the lid is applied and subjected to the high-temperature and high-pressure treatment in the same manner as described above, when the fitting portion 8 is pulled out from the cylindrical wall portion 7 in the high-temperature state, the backup ring 3 expands in the outer diameter direction due to thermal expansion and tends to protrude greatly from the annular groove 9, but the annular ridge 60 (outer diameter circumferential surface portion 61) and the locking protrusion 62 (step surface 15) Since they are in contact and locked, the locking protrusion 62 prevents the backup ring 3 from expanding in the outer diameter direction and prevents the protrusion from protruding greatly from the annular groove 9.

As described above, the sealing structure of the present invention includes the annular groove 9 formed on the outer peripheral surface of the fitting portion 8 that is detachably fitted in the cylindrical portion 7 of the high-temperature and high-pressure processing apparatus, and the high-pressure of the annular groove 9. A sealing ring 1 for sealing that is mounted to face the first side wall surface 13 on the side H, and a rear surface 4 of the sealing ring 1 that is mounted to face the second side wall surface 14 on the low pressure side L of the annular groove 9. A ring-shaped protruding portion 6 bulging toward the seal ring 1 is formed on the receiving surface 5 of the backup ring 3 in contact with the back surface 4. Since the stepped surface 11 that engages with the outer circumferential surface portion 10 of the annular convex ridge 6 is formed on the back surface 4 in the uncompressed state, the heat is generated when the fitting portion 8 is pulled out from the tubular portion 7 in a high temperature state. The back-up ring 3 to be expanded in the outer diameter direction by expansion is locked by the step surface 11 of the seal ring 1 Thus, expansion in the outer diameter direction can be suppressed. And it can prevent that the backup ring 3 protrudes largely from the annular groove 9 (projects out). Therefore, when the fitting portion 8 is inserted into the cylindrical portion 7 again in the high temperature state, there is no possibility that the backup ring 3 is sandwiched between the fitting portion 8 and the cylindrical portion 7 and damaged. The portion 8 can be smoothly inserted and fitted into the cylindrical portion 7.
Furthermore, since the seal ring 1 and the backup ring 3 can be separated, they can be replaced independently. That is, unlike the conventional seal member in which the seal ring 1 and the backup ring 3 are bonded, the service life of one of them is not limited to the other product life that deteriorates quickly, and the use cost is excellent.

  Further, the seal ring 1 is formed in a U-shaped cross section having a concave groove 16 that opens to the first side wall surface 13 side, and has a metal elastic member 2 in the concave groove 16, that is, the linear expansion coefficient. Since the metal elastic member 2 having a small size and high strength is housed in the seal ring 1, the expansion of the backup ring 3 in the outer diameter direction due to thermal expansion can be more effectively suppressed.

Moreover, the annular groove 9 formed in the outer peripheral surface of the fitting part 8 detachably fitted in the cylindrical part 7 of the high temperature and high pressure processing apparatus, and the first side wall surface 13 on the high pressure side H of the annular groove 9 are opposed. A sealing ring 1 for sealing, and a resin backup ring 3 that is mounted to face the second side wall surface 14 on the low pressure side L of the annular groove 9 and supports the back surface 4 of the sealing ring 1. Is formed on the abutment surface 12 of the backup ring 3 in contact with the second side wall surface 14 so as to bulge to the second side wall surface 14 in an uncompressed state. Since the stepped surface 15 that engages with the outer circumferential surface portion 61 of the annular convex ridge 60 is formed on the second side wall surface 14, when the fitting portion 8 is pulled out from the tubular portion 7 at a high temperature, The backup ring 3 to be expanded in the outer diameter direction is locked by the step surface 15 of the second side wall surface 14 to expand the outer diameter direction. It is possible to stop. And it can prevent that the backup ring 3 protrudes largely from the annular groove 9 (projects out). Therefore, when the fitting portion 8 is inserted into the cylindrical portion 7 again in the high temperature state, there is no possibility that the backup ring 3 is sandwiched between the fitting portion 8 and the cylindrical portion 7 and damaged. The portion 8 can be smoothly inserted and fitted into the cylindrical portion 7.
Furthermore, since the seal ring 1 and the backup ring 3 can be separated, they can be replaced independently. That is, unlike the conventional seal member in which the seal ring 1 and the backup ring 3 are bonded, the service life of one of them is not limited to the other product life that deteriorates quickly, and the use cost is excellent.

It is sectional drawing of the sealing structure which concerns on this invention. It is principal part sectional drawing. It is principal part sectional drawing. It is sectional drawing of a seal ring and a resilient member. It is sectional drawing of a backup ring. It is principal part sectional drawing which shows other embodiment of this invention. It is principal part sectional drawing. It is sectional drawing of the conventional sealing structure. It is principal part sectional drawing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Seal ring 2 Elastic member 3 Backup ring 4 Back surface 5 Receiving surface 6 Annular convex part 7 Cylindrical part 8 Fitting part 9 Annular groove
10 Outer diameter peripheral surface
11 Step surface
12 Contact surface
13 First side wall
14 Second side wall
15 Step surface
16 groove
60 Annular protuberance
61 Outer peripheral surface H High pressure side L Low pressure side

Claims (3)

An annular groove (9) formed on the outer peripheral surface of the fitting part (8) detachably fitted in the cylindrical part (7) of the high-temperature and high-pressure processing apparatus, and a high-pressure side (H of the annular groove (9)) ) Facing the first side wall surface (13) and the sealing ring (1) for sealing, and the second side wall surface (14) on the low pressure side (L) of the annular groove (9). In a sealing structure comprising a resin backup ring (3) which is mounted and supports the back surface (4) of the seal ring (1).
An annular ridge (6) bulging toward the seal ring (1) is formed on the receiving surface (5) of the backup ring (3) in contact with the back surface (4), and the back surface is mounted in an uncompressed state. (4) A sealing structure characterized in that a stepped surface (11) that engages with the outer peripheral surface portion (10) of the annular convex ridge (6) is formed.   The seal ring (1) is formed in a U-shaped cross section having a groove (16) that opens to the first side wall surface (13) side, and a metal elastic member ( The sealing structure according to claim 1, comprising 2). An annular groove (9) formed on the outer peripheral surface of the fitting part (8) detachably fitted in the cylindrical part (7) of the high-temperature and high-pressure processing apparatus, and a high-pressure side (H of the annular groove (9)) ) Facing the first side wall surface (13) and the sealing ring (1) for sealing, and the second side wall surface (14) on the low pressure side (L) of the annular groove (9). In a sealing structure comprising a resin backup ring (3) which is mounted and supports the back surface (4) of the seal ring (1).
An annular ridge (60) that bulges to the second side wall surface (14) is formed on the contact surface (12) of the backup ring (3) that is in contact with the second side wall surface (14). A sealing structure characterized in that a stepped surface (15) is formed on the second side wall surface (14) in a compressed state to engage with the outer peripheral surface portion (61) of the annular ridge (60).

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