JP2000046199A - Mechanical seal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanical seal that serves both as a rotary type and as a stationary type and also operates as a stationary type with or without baffle sleeves. SOLUTION: A collar 2 is formed with O-ring grooves 3 and 4 cut in its respective internal and external surfaces and with a tapped hole 5 and a quenching hole 6 passed across the internal and external surfaces of one portion. As a rotary type, an O-ring 18 is fitted in the internal O-ring groove 3 and a set screw 24 is driven for engagement into the tapped hole 5 from the exterior or against a rotary shaft 25. As a stationary type, on the other hand, an O-ring 18 is fitted in the external O-ring groove 4 and a set screw 24 is driven for engagement into the tapped hole 5 from the interior or against a housing 20. As a further stationary type using a baffle sleeve 12, a quenching liquid injected in through the quenching hole 6 is led to the sliding surface via the baffle sleeve 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical seal, and more particularly, to a rotary type in which a seal ring, a bellows and a collar are mounted on a rotary shaft side and a stationary type in which they are mounted on a housing side. The present invention relates to a bellows-type mechanical seal that can be used both when a sleeve is used and when it is not used.

[0002]

2. Description of the Related Art Bellows-type mechanical seals are classified into a rotary type and a stationary type.
The bellows and the seal ring are configured to be mounted on the rotating shaft side, and the stationary type is configured to be mounted on the housing side.

[0003] In the case of the rotary type, the seal end face of the seal ring attached to the rotary shaft side and the seal end face of the mating ring attached to the housing side are brought into contact with each other, so that the rotary shaft and the housing are separated from each other. In the case of a stationary type, the seal end face of the seal ring attached to the housing side and the seal end face of the mating ring attached to the rotating shaft side come into contact with each other,
It can seal between the rotating shaft and the housing.

In the case of a stationary type, there are cases where a baffle sleeve is used and cases where it is not used. When a baffle sleeve is used, a quenching liquid is guided to a sliding surface through a baffle sleeve. Fluid leaking from the sliding surface can be discharged to the outside.

FIG. 2 shows an example of a mechanical seal that uses a baffle sleeve in a stationary form. The mechanical seal 31 includes a metal collar 32 attached to the housing 50 side, a metal bellows 37 connected to the collar 32 by welding or the like, and a metal adapter 38 connected to the bellows 37 by welding or the like. , A seal ring 40 made of carbon to be fitted to the adapter 38, and a collar 32, a bellows 37, the adapter 38, the seal ring 40,
5 and a baffle sleeve 42 located between the
A metal sleeve 47 attached to the fifth side, an adapter 48 fitted to the sleeve 47, and a carbon mating ring 45 fitted to the adapter 48 are provided.

Then, the sealing end face 41 of the sealing ring 40 attached to the housing 50 is brought into contact with the sealing end face 46 of the mating ring 45 attached to the rotating shaft 55 side, and the sealing ring 4 is biased by the bellows 37.
0 in the direction of the mating ring 45, and by rotating the rotating shaft 55 in this state, the seal end surface 46 of the mating ring 45 and the seal end surface 41 of the seal ring 40 come into sliding contact with each other, The space between the rotating shaft 55 and the housing 50 is sealed.

The housing 50 is provided with a quenching hole 51 communicating with the outer peripheral side of the baffle sleeve 42. By injecting the quenching liquid from the quench hole 51, the quenching liquid is supplied to the baffle sleeve 4.
2 is guided to the sliding surface between the seal ring 40 and the mating ring 45 through the outer peripheral surface of the second ring 2, and the fluid leaking from the sliding surface is discharged through the gap between the baffle sleeve 42 and the rotating shaft 55. It is guided to 52 and discharged to the outside through the discharge hole 52.

However, in the mechanical seal 31 having the above-described structure, the quenching hole 51 is provided in the housing 50 on the outer side in the axial direction of the collar 32, and the baffle sleeve 42 is fixed to the outside thereof. Since the screw holes (not shown) are provided, the thickness of the housing 50 in the axial direction increases. For this reason, the mounting space becomes long in the axial direction,
Installation may not be possible. In addition, the cost is increased as a whole. Further, since the bellows 37 does not have a function of suppressing the vibration of the bellows 37, the bellows 37 is fatigued in a short period of time. Since both the rotary type and the stationary type cannot be used, it is necessary to prepare ones corresponding to the respective specifications.

The present invention solves the above-mentioned problems of the prior art, and can be used for both the rotary type and the stationary type, and also uses the baffle sleeve in the stationary type. However, it is an object of the present invention to provide a mechanical seal in which the thickness of the housing in the axial direction does not increase, and the mounting space does not increase in the axial direction and the mounting becomes impossible. is there. It is another object of the present invention to provide a mechanical seal capable of suppressing the vibration of the bellows and greatly improving the durability of the bellows. Another object of the present invention is to provide a mechanical seal that can be used for both a rotary type and a stationary type.

[0010]

According to the present invention, there is provided a mechanical seal provided between a rotating shaft and a housing to seal between the two.
A seal ring having a seal end face perpendicular to the axis of the rotary shaft, a collar attached to the seal ring via a bellows, and a seal end face perpendicular to the axis of the rotary shaft in contact with the seal end face of the seal ring; A mating ring is provided, and O-ring grooves are provided on the inner peripheral surface and the outer peripheral surface of the collar, respectively, and a part of the collar is provided with a screw hole penetrating between the inner and outer peripheral surfaces. is there. In addition, a baffle sleeve is provided between the seal ring, the bellows and the collar and the rotating shaft, and a part of the baffle sleeve is fixed to the collar, and a part of the collar penetrates between the inner and outer peripheral surfaces. A means having a quenching hole is adopted. Further, a means in which a narrow portion with a minute gap is formed on the outer peripheral side of the baffle sleeve is employed.

[0011]

According to the present invention, an O-ring is mounted in the O-ring groove on the inner peripheral side of the collar when the rotary type is used as a rotary type. Attaching to the side seals between the collar and the rotating shaft. When used as a stationary type, an O-ring is mounted in the O-ring groove on the outer peripheral side of the collar, and in this state, the collar is attached to the housing to seal the space between the collar and the housing. Also, by injecting the quenching liquid from the quenching hole of the collar, the quenching liquid is guided to the sliding surface between the seal ring and the mating ring, and the fluid leaking from the sliding surface is discharged to the outside. Can be done. Further, the vibration of the bellows can be suppressed by the throttle portion on the outer peripheral side of the baffle sleeve.

[0012]

Embodiments of the present invention shown in the drawings will be described below. FIG. 1 shows an embodiment of a mechanical seal according to the present invention. The mechanical seal 1 according to this embodiment is mounted between a rotating shaft 25 and a housing 20 to seal between them. It is a bellows type mechanical seal, and it is a color 2,
It includes a bellows 7 connected to the collar 2, an adapter 8 connected to the bellows 7, a seal ring 10 fitted to the adapter 8, a baffle sleeve 12, and a mating ring 15.

The collar 2 has a cylindrical shape formed of metal, and annular O-ring grooves 3 and 4 are formed at predetermined depths on the inner and outer peripheral surfaces at one end in the axial direction. In addition, a screw hole 5 and a quenching hole 6 penetrating between the inner and outer peripheral surfaces are provided at at least one place at the other end in the axial direction, and a screw hole in the axial direction is provided at one end surface in the axial direction. (Not shown) at a predetermined depth.

The bellows 7 is formed by arranging a plurality of metal diaphragm plates formed in a corrugated ring by punching or the like in a line, and alternately connecting the outer diameter portions and the inner diameter portions of adjacent diaphragm plates by gas welding or the like. The whole is formed in a bellows cylindrical shape, and one end is integrally connected to the collar 2 side by gas welding or the like.

The adapter 8 has a cylindrical shape formed of metal, and has an annular step 9 formed at one end on the inner peripheral surface side. The outer peripheral side of the seal ring 10 is fitted into the step 9. Are to be combined. The other end of the bellows 7 is integrally connected to the adapter 8 by gas welding or the like.

The seal ring 10 is made of carbon and has a cylindrical shape. The outer peripheral side of the seal ring 10 is fitted into the step 9 of the adapter 8 so as to be integrally attached to the adapter 8. I have. One end face in the axial direction of the seal ring 10 is formed on a seal end face 11 perpendicular to the axis of the rotating shaft 25.

The baffle sleeve 12 is formed in a cylindrical shape, and has a flange portion 13 which is formed integrally at one end in the axial direction so as to protrude annularly outward in the radial direction. A plurality of holes (not shown) penetrating in the axial direction are provided at a plurality of positions of the flange portion 13, and the bolts 23 passing through the holes are screwed into the screw holes 5 of the collar 2 and tightened to baffle the collar 2. The sleeve 12 can be fixed.

Between the outer peripheral surface of the baffle sleeve 12 and the inner peripheral surface of the adapter 8, there is formed a narrowed portion 14 with a small gap, and the narrowed portion 14 reduces the vibration of the bellows 7 when the quenching liquid flows. Thus, the bellows 7 can be suppressed from being fatigued.

The mating ring 15 has a cylindrical shape made of carbon. One end surface in the axial direction is formed on a seal end surface 16 perpendicular to the axis of the rotating shaft 25. The mating ring 15 is attached to the housing 20 alone when used as a rotary type, and is attached to the rotary shaft 25 via a sleeve 17 and the like when used as a stationary type. I have. 19 is the sleeve 17 and the mating ring 1
5 is an O-ring that seals between the O-rings.

The housing 20 is provided with a quenching hole 21 that communicates with the quenching hole 6 of the collar 2. The quenching liquid is injected from the quenching holes 6 and 21, so that the quenching liquid flows around the baffle sleeve 12. The fluid guided to the sliding surface between the seal ring 10 and the mating ring 15 through the surface and leaking from the sliding surface is provided to the housing 20 via a gap between the baffle sleeve 12 and the rotating shaft 25. It can be discharged to the outside through the discharge hole 22 which is formed.

When the mechanical seal 1 constructed as described above is used as a stationary type, as shown in FIG. 1, the sleeve 17 is fitted on the rotating shaft 25 and the O.S. The mating ring 15 is fitted via the ring 19.

An O-ring 18 is mounted in the O-ring groove 4 on the outer peripheral surface of the collar 2. In this state, the collar 2, the bellows 7, the adapter 8 and the seal ring 10 are positioned on the inner peripheral side of the housing 20. The collar 2 is fitted to the inner peripheral side of the housing 20, the set screw 24 is screwed into the screw hole 5 of the collar 2 from the inner peripheral side, and the collar 2 is fixed to the housing 20 by tightening with a predetermined torque. .

A baffle sleeve 1 is provided on the inner peripheral side of the collar 2, the bellows 7, the adapter 8, and the seal ring 10.
2, the flange 13 is brought into contact with the end face of the collar 2, the hole of the collar 13 is made to coincide with the screw hole of the collar 2, and the bolt 23 is inserted through the hole of the collar 13, and the screw hole of the collar 2 is inserted. The baffle sleeve 12 is fixed to the collar 2 by tightening with a predetermined torque.

Then, the rotary shaft 25 is inserted through the inner peripheral side of the baffle sleeve 12 so that the seal end face 11 of the seal ring 10 and the seal end face 16 of the mating ring 15 come into contact with each other. Press both end surfaces in the direction of approach.

Then, a seal member 26 is mounted between the rotary shaft 25 and the housing 20, and one end in the axial direction between the two is sealed.

Thus, the color 2, the bellows 7,
The adapter 8 and the seal ring 10 are attached to the housing 20 side, and the mating ring 15 is attached to the rotating shaft 25 side. When the rotating shaft 25 is rotated in this state, the sealing end face 11 of the seal ring 10 and the mating ring 15
And the seal end face 16 is in sliding contact with each other to seal between the rotating shaft 25 and the housing 20.

In this case, the O-ring 18 functions as a secondary seal to seal between the housing 20 and the O-ring 19 functions as a secondary seal to seal between the O-ring 19 and the rotating shaft 25. It is.

On the other hand, when the mechanical seal 1 having the above-described configuration is used as a rotary type, the mating ring 15 is fixed to the housing 20 and the O 2 on the inner peripheral side of the collar 2 is not shown. O in ring groove 3
The rotating shaft 25 is inserted through the collar 2, the bellows 7, the adapter 8, and the inner peripheral side of the seal ring 10 in this state.
Is brought into contact with the sealing end face 16 of the mating ring 15, the set screw 24 is screwed into the screw hole 5 of the collar 2 from the outer peripheral side, and the collar 2 is fixed to the rotating shaft 25 by tightening with a predetermined torque. Become.

In the mechanical seal 1 according to this embodiment constructed as described above, the O-ring grooves 3 and 4 are provided on the inner and outer peripheral surfaces of the collar 2 and the screw which penetrates the collar 2 between the inner and outer peripheral surfaces. When the hole 5 is screwed, the O-ring 18 is mounted in the O-ring groove 3 on the inner peripheral side, and the set screw 24 is screwed into the screw hole 5 from the outer peripheral side when used as a rotary type. When the collar 2 is fixed to the rotating shaft 25 side by tightening, the O-ring 18 is mounted in the O-ring groove 4 on the outer peripheral side and set in the screw hole 5 from the inner peripheral side. The collar 2 may be fixed to the housing 20 by screwing and tightening the screw 24.

Therefore, it can be used for both the rotary type and the stationary type without changing the structure.

When the baffle sleeve 12 is used in a stationary state, the quenching hole 6 is provided in the collar 2 and a screw hole for fixing the baffle sleeve 12 is provided, so that the thickness of the housing 20 in the axial direction is provided. Is no longer thickened.

Therefore, the mounting space does not become long in the axial direction, and the mounting does not become difficult. Further, since the thickness of the housing 20 in the axial direction can be reduced, the overall cost can be reduced, and the quenching mechanism including the baffle sleeve can be employed even in a small space, so that the life can be extended.

Further, the adapter 8 and the baffle sleeve 1
By providing the narrowed portion 14 with a small gap between
Vibration of the bellows 7 when the quenching liquid flows can be reduced.

Therefore, fatigue of the bellows 7 can be suppressed, and durability can be greatly improved.

[0035]

According to the present invention, an O-ring groove is provided on each of the inner and outer peripheral surfaces of the collar, and a screw hole is provided in a part of the collar so as to penetrate between the inner and outer peripheral surfaces. Therefore, when using as a rotary type, install an O-ring in the O-ring groove on the inner peripheral side of the collar, attach the collar to the rotating shaft side in this state, and screw the screw into the screw hole from the outer peripheral side Then, the collar, the bellows and the seal ring can be fixed to the rotating shaft side by tightening with a predetermined torque. Also, when used as a stationary type, an O-ring is mounted in the O-ring groove on the outer peripheral side of the collar, the collar is mounted on the housing side in this state, a screw is screwed into the screw hole from the inner peripheral side, By tightening with a predetermined torque, the collar, the bellows and the seal ring can be fixed to the housing side. Therefore, both the rotary type and the stationary type can be used without changing the structure.

Further, by providing a quench hole penetrating between the inner and outer peripheral surfaces in a part of the collar, when the baffle sleeve is used in a stationary form, a space for providing the quench hole is provided in the axial direction. There is no need for much. Therefore, the thickness of the housing in the axial direction does not increase, and the mounting does not become difficult. Furthermore, since the thickness of the housing in the axial direction can be reduced, a quenching mechanism having a baffle sleeve can be employed even in a small space, and the life can be extended. Further, since the housing can be made thin, the cost as a whole can be reduced.

By forming the narrowed portion with a minute gap between the baffle sleeve and the baffle sleeve, the vibration of the bellows when the quenching liquid flows can be reduced. Therefore, fatigue of the bellows can be suppressed, and durability can be greatly increased.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a mechanical seal according to the present invention, which is a schematic sectional view when the mechanical seal is used in a stationary form.

FIG. 2 is a schematic cross-sectional view showing an example of a conventional mechanical seal, and is a schematic cross-sectional view when used in a stationary form.

[Explanation of symbols]

 1, 31 mechanical seal 2, 32 collar 3, 4 O-ring groove 5 screw hole 6, 21, 51 quenching hole 7, 37 bellows 8, 38, 48 adapter 9 Step section 10, 40 Seal ring 11, 16, 41, 46 Seal end face 12, 42 Baffle sleeve 13 Flange section 14 Drawing section 15, 45 Mating ring 17, 47 sleeve 18, 19 O-ring 20, 50 housing 22, 52 discharge hole 23 bolt 24 set screw 25, 55 rotating shaft 26 seal member

Claims (3)

[Claims] 1. A mechanical seal provided between a rotating shaft and a housing for sealing between the two, comprising: a sealing ring having a sealing end face perpendicular to the axis of the rotating shaft; And a mating ring having a seal end surface perpendicular to the axis of the rotating shaft that comes into contact with the seal end surface of the seal ring, and provided with O-ring grooves on the inner peripheral surface and the outer peripheral surface of the collar, respectively. A mechanical seal, wherein a screw hole is provided in a part of the collar so as to penetrate between the inner and outer peripheral surfaces. 2. A baffle sleeve is provided between the seal ring, the bellows and the collar and the rotating shaft, a part of the baffle sleeve is fixed to the collar, and a part of the collar has inner and outer peripheral surfaces. 2. The mechanical seal according to claim 1, wherein a quenching hole penetrating therethrough is provided. 3. The mechanical seal according to claim 2, wherein a narrowed portion with a minute gap is formed on an outer peripheral side of the baffle sleeve.