JPH073095Y2 - mechanical seal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is intended to facilitate maintenance of mechanical seals, particularly mechanical seals used as shaft sealing means for shafts having a relatively large diameter.

[Conventional technology]

Conventionally, as a shaft sealing device for a shaft having a relatively large diameter, there is a mechanical seal as shown in FIG.

That is, this mechanical seal is a so-called inflow type, and the outer diameter portion is the inner diameter portion of the end surface on the atmosphere A side of the housing 101 and the flange 103 fixed to the end surface by a bolt 102.
The ring-shaped recess 104 formed between the O-ring 1 and
The stationary side sealing ring 106 fixed via 05 and the stationary side sealing ring 106 on the inner side of the machine and on the outer peripheral surface of the shaft 107
It has a stationary side seal ring 106 and a rotating side seal ring 109 that seals and slides, which is mounted movably in the axial direction via a ring 108, and prevents the fluid B to be sealed in the machine from leaking to the atmosphere A side. is there.

[Problems to be solved by the device]

However, according to the mechanical seal having the conventional structure described above, when it is necessary to replace the sealing rings 106 and 109 due to the progress or damage of the sliding surface, the flange 103 has to be removed from the housing 101, which is large. Equipment (shaft 1
(07 is a large diameter), this removal work was extremely difficult.

In view of such a point, the present invention has an object to facilitate replacement work of a large mechanical seal for axially sealing a large-diameter shaft.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, according to the present invention, the stationary side seal ring is located on the atmosphere side of the rotating side seal ring, and the outer diameter portion of the stationary side seal ring is the inner diameter portion of the atmosphere side end surface of the housing. In a mechanical seal having a structure fixed to an annular recess formed between the inner diameter of a flange fixed to and through a packing, the stationary seal ring is fixed to the annular recess through a packing. An outer diameter retainer, a stationary sliding piece that is airtightly and axially insertably / removably fitted to the inner peripheral surface of the outer diameter retainer, and has a sliding surface with the rotary side sealing ring; and And a rotary retainer in which the rotary seal ring is mounted on the rotary shaft in an airtight and axially movable manner, and an inner diameter retainer that supports the opposite sliding surface side and is screwed to the outer retainer. Sealing the stationary side of this rotary retainer Has a sliding surface that is hermetically and axially insertably / removably fitted to the stationary sliding piece, and has a diameter smaller than the inner peripheral surface of the outer diameter retainer. It is configured to include a rotary sliding piece.

[Action]

According to the above configuration, when the stationary side and rotating side sealing ring sliding surfaces are worn or damaged, it is not necessary to replace the stationary side and rotating side sealing rings as a whole, and only the sliding piece can be replaced. Good. When replacing the rotary sliding piece of the rotating side sealing ring, if the static sliding piece is pulled out of the machine (atmosphere side) from the outside diameter retainer by removing the inner diameter retainer that constitutes the stationary side sealing ring, It can be pulled out of the machine via the inner circumference of the retainer and replaced with a new sliding piece.

〔Example〕

The present invention will be described below with reference to an embodiment shown in FIG.

In the figure, reference numeral 1 is a housing, 2 is the atmosphere A of the housing 1.
The flanges 3 fixed to the side end surface 1a are shafts inserted into the inner peripheral holes of the housing 1 and the flange 2.

In the mechanical seal of this embodiment, reference numeral 6 denotes a stationary seal ring located on the atmosphere A side in the axial direction, which is the housing 1
An outer diameter retainer 7 clamped and fixed in an annular recess 4 formed between the inner diameter portion of the end surface 1a and the inner diameter portion of the flange 2 via O-rings 5, 5 as packings, and the outer diameter retainer 7 A stationary sliding piece 8 having a sliding surface 8a that is airtightly and axially insertably and detachably fitted to the inner peripheral surface of the
An inner diameter retainer 9 that supports the opposite sliding surface side of the stationary sliding piece 8 and is fixed to the inner circumference of the outer diameter retainer 7 by a bolt 10.
And consists of. Reference numeral 12 is a knock pin that engages with the notch 13 of the stationary sliding piece 8 and holds the stationary sliding piece 8 in a non-rotating state.

Numeral 15 is a rotating side sealing ring which is on the in-machine (sealing target fluid B) side of the stationary side sealing ring 6 and rotates integrally with the shaft 3, and is hermetically sealed on the outer peripheral surface of the shaft 3 via an O-ring 14. A rotary retainer 16 mounted so as to be movable in the axial direction, and an annular step portion 17 formed on the inner circumference of the end portion of the rotary retainer 16 on the stationary side sealing ring 6 side are hermetically and axially inserted through an O-ring 18. It comprises a rotary sliding piece 19 which is detachably fitted and has a sliding surface 19a with the stationary sliding piece 8. Reference numeral 20 is a knock pin that engages with the notch 21 of the rotary sliding piece 19 in the circumferential direction and prevents relative rotation of the rotary sliding piece 19 and the rotary retainer 16.
Further, the outer diameter dimension of the rotary sliding piece 19 is set to be slightly smaller than the inner diameter dimension of the outer diameter retainer 7 in the stationary side seal ring 6.

22 is a compression ring that engages with the end of the rotary retainer 16 on the side opposite to the rotary sliding piece, and 23 is between the compression ring 22 and a collar 25 that is tightened and fixed to the outer peripheral surface of the shaft 3 with a set screw 24. A coil spring 26 mounted in a compressed state is a drive pin 26 which engages the collar 25 and the rotary retainer 16 with each other in the circumferential direction. That is, the rotary seal ring 15 is rotated by the rotational driving force of the shaft 3 transmitted through the collar 25 and the compression ring 22 and is axially pressed by the coil spring 23 through the compression ring 22 to rotate. The sliding surface 19a of the sliding piece 19 closely slides on the sliding surface 8a of the stationary sliding piece 8 of the stationary side seal ring 6 to perform a shaft sealing function.

According to the above configuration, when the sliding surface 8a or 19a is worn or damaged, the stationary side seal ring 6 or the rotating side seal ring 6
Obviously, it is not necessary to replace the entire 15, that is, only the stationary slide piece 8 or the rotary slide piece 19 need be replaced. At that time, it is not necessary to remove the flange 2 from the housing 1, and the fastening of the bolt 10 is released, and the inner diameter retainer 9 is removed from the outer diameter retainer 7 of the stationary side seal ring 6. Also, the rotary sliding piece 19 can be extracted to the outside of the machine (atmosphere A side).

[Effect of device]

As described above, according to the present invention, when the sliding surface is worn or damaged, only the stationary side and rotating side sliding pieces need to be replaced, and the inner diameter retainer forming the stationary side sealing ring must be removed at the time of replacement. If the static sliding piece is pulled out from the outer diameter retainer to the outside of the machine (atmosphere side), the rotary sliding piece of the rotating side seal ring can also be pulled out to the outside of the machine through the inner circumference of the outer diameter retainer, so the flange This eliminates the need for laborious work such as removal, and makes maintenance extremely easy.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a half sectional view showing an embodiment of the present invention, and FIG. 2 is a half sectional view showing a conventional example. 1 ... Housing, 2 ... Flange, 3 ... Shaft 4 ... Annular recess, 5 ... Packing (O-ring) 6 ... Stationary side sealing ring, 7 ... Outer diameter retainer 8 ... Stationary sliding piece, 8a, 19a ... Sliding surface 9 … Inner diameter retainer, 15… Rotating side sealing ring 16… Rotating retainer, 19… Rotating sliding piece, A… Atmosphere

Claims (1)

[Scope of utility model registration request] 1. The stationary seal ring is located on the atmosphere side of the rotary seal ring, and the outer diameter portion of the stationary seal ring is composed of an inner diameter portion of an end surface of the housing on the atmosphere side and a flange fixed to the end surface. In a mechanical seal having a structure fixed to an annular recess formed between the inner diameter part and a packing,
An outer diameter retainer, in which the stationary side seal ring is fixed to the annular recess via packing, and an inner peripheral surface of the outer diameter retainer, which is airtightly and axially insertably / removably fitted to the rotary side seal ring. A stationary sliding piece having a sliding surface of, and an inner diameter retainer that supports the opposite sliding surface side of the stationary sliding piece and is screwed to the outer diameter retainer, and the rotating side sealing ring,
A rotary retainer mounted on a rotary shaft in an airtight manner and movable in the axial direction, and an airtight and axially insertable / removable manner in an annular step formed at an end of the rotary retainer on the stationary side seal ring side. A mechanical seal, which is fitted and has a sliding surface with the stationary sliding piece, and a rotary sliding piece having a smaller diameter than the inner peripheral surface of the outer diameter retainer.