JP2018062948A - Mechanical seal and sealed structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanical seal and sealed structure for improving a cooling effect.SOLUTION: Sealed structure includes: a rotating shaft 300; a housing 200 including a shaft hole 201 into which the rotating shaft 300 is inserted; and a mechanical seal 100 including a rotary ring 160 fixed to the rotating shaft 300, and fixed rings (a first fixed ring 150 and a second fixed ring 170) that are fixed to the housing 200 and slide relative to the rotary ring 160. In the sealed structure configured such that a quenching liquid flows to an area at an outer peripheral side of the rotary ring 160 and the fixed rings, a passage that is configured so as to communicate with the other end side end face from one end side end face and becomes a flow path through which the quenching liquid flows.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a mechanical seal and a sealing structure including a rotating ring and a fixed ring.

  In the mechanical seal, heat is generated by sliding between the stationary ring and the rotating ring. Therefore, in order to suppress deterioration due to heat, a technique is known in which a coolant is supplied to suppress the temperature rise of the mechanical seal. However, there are cases where the temperature rise of the mechanical seal cannot be sufficiently suppressed by simply flowing the coolant.

International Publication No. 2011/007765

  The objective of this invention is providing the mechanical seal and sealing structure which aimed at the improvement of the cooling effect.

  The present invention employs the following means in order to solve the above problems.

The mechanical seal of the present invention is
A rotating ring fixed to the rotation axis;
A fixed ring that is fixed to a housing having a shaft hole through which the rotary shaft is inserted and that slides with respect to the rotary ring;
A mechanical seal comprising:
The stationary ring is configured to communicate with one end side end face to the other end side end face, and is formed with a passage serving as a flow path through which the coolant flows.

The sealing structure of the present invention is
A rotation axis;
A housing having a shaft hole through which the rotating shaft is inserted;
A mechanical seal having a rotating ring fixed to the rotating shaft, and a fixed ring fixed to the housing and sliding with respect to the rotating ring;
In a sealing structure configured to allow cooling liquid to flow in a region on the outer peripheral surface side of the rotating ring and the stationary ring,
The stationary ring is configured to communicate with one end side end face to the other end side end face, and is formed with a passage serving as a flow path through which the coolant flows.

  According to these inventions, since the coolant flows in the passage configured to communicate from the end surface on one end side to the end surface on the other end side in the stationary ring, the contact area between the stationary ring and the coolant can be increased. it can. Thereby, the cooling effect of a stationary ring can be made high.

  The passage may be constituted by a communication groove, and the coolant may be in contact with the entire inner wall surface of the communication groove.

It is also preferable that the passage is constituted by a through hole and that the coolant is in contact with the entire inner wall surface of the through hole.

  Furthermore, an annular groove may be formed in the center of the outer peripheral surface of the rotating ring.

  Thereby, since a cooling fluid flows into an annular groove, the contact area of a rotating ring and a cooling fluid can be enlarged. Thereby, the cooling effect of a rotating ring can be made high.

  In addition, said each structure can be employ | adopted combining as much as possible.

  As described above, according to the present invention, the cooling effect can be improved.

FIG. 1 is a schematic cross-sectional view of a sealing structure including a mechanical seal according to an embodiment of the present invention. FIG. 2 is a partial side view of a stationary ring according to an embodiment of the present invention. FIG. 3 is a schematic cross-sectional view of a stationary ring according to an embodiment of the present invention. FIG. 4 is a part of a side view of a stationary ring according to a modification of the present invention. FIG. 5 is a schematic cross-sectional view of a stationary ring according to a modification of the present invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be exemplarily described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. .

(Example)
With reference to FIGS. 1-5, the mechanical seal and sealing structure based on the Example of this invention are demonstrated. FIG. 1 is a schematic cross-sectional view of a sealing structure including a mechanical seal according to an embodiment of the present invention. In addition, the mechanical seal in FIG. 1 has shown the cross section cut | disconnected by the surface containing the center axis line of a rotating shaft. However, in FIG. 1, for convenience of explanation, in order to show characteristic parts, the phase of the cutting position (position in the circumferential direction) is appropriately different. Moreover, in FIG. 1, only a cut surface is shown and the depth line is omitted as appropriate. FIG. 2 is a partial side view of a stationary ring according to an embodiment of the present invention. FIG. 3 is a schematic cross-sectional view of a stationary ring according to an embodiment of the present invention, and is a cross-sectional view taken along AA in FIG. FIG. 4 is a part of a side view of a stationary ring according to a modification of the present invention. FIG. 5 is a schematic cross-sectional view of a stationary ring according to a modification of the present invention, and is a BB cross-sectional view in FIG.

<Sealing structure>
In particular, with reference to FIG. 1, a sealing structure including a mechanical seal 100 according to the present embodiment will be described. The mechanical seal 100 according to the present embodiment seals an annular gap between the housing 200 of the rotating machine and the rotating shaft 300 inserted through the shaft hole 201 of the housing 200, and is an in-machine area that is an area in the rotating machine. The fluid in region A (right side in FIG. 1) is sealed. The mechanical seal 100 includes a flange 110 fixed to the housing 200 by bolts and a stuffing box 120 from the outside area B side (left side in FIG. 1) that is an area outside the housing 200. The mechanical seal 100 further includes a seal cover 130 fixed to the stuffing box 120 by bolts from the outside region B side. The flange 110, the stuffing box 120, and the seal cover 130 are all annular members made of a metal such as stainless steel. A bearing 140 that supports the rotary shaft 300 via a metal sleeve 310 fixed to the outer peripheral surface of the rotary shaft 300 is fixed on the radially inner side of the seal cover 130. The sleeve 310 is fixed to the rotary shaft 300 by a sleeve collar 320 having two set screws. The annular gap between the stuffing box 120 and the sleeve 310 is sealed with a rubber oil seal 401. An annular gap between the seal cover 130 and the sleeve 310 is sealed by a rubber oil seal 402, and an annular gap between the rotary shaft 300 and the sleeve 310 is sealed by an O-ring.

  The mechanical seal 100 includes a first fixed ring 150 fixed to the housing 200 via the flange 110 and a rotary ring 160 fixed to the rotary shaft 300 via the sleeve 310. The mechanical seal 100 also includes a second fixed ring 170 fixed to the housing 200 via the stuffing box 120 and the flange 110. The first stationary ring 150, the rotating ring 160, and the second stationary ring 170 (hereinafter also referred to as sliding rings) are made of a hard sliding material. For example, the first fixed ring 150 and the second fixed ring 170 are preferably made of carbon that also has self-lubricating properties, and the rotating ring 160 is preferably made of silicon carbide.

  The first fixed ring 150 is urged in the axial direction toward the rotary ring 160 by a spring 111 provided on the flange 110. Further, the rotation of the first fixed ring 150 with respect to the flange 110 is prevented by a rotation stop pin 112 that engages with a notch 151 formed in the first fixed ring 150. The notch 151 has a shape that is notched radially inward from the outer peripheral surface of the first fixed ring 150. An annular gap between the first fixed ring 150 and the flange 110 (specifically, an annular gap between the outer peripheral surface of the portion of the first fixed ring 150 on the in-machine region A side and the inner peripheral surface of the flange 110) ) Is sealed by an O-ring. As described above, the first fixed ring 150 is fixed to the flange 110 in a state where a certain amount of movement is allowed.

  The rotary ring 160 is axially positioned by a collar 330 fixed to the sleeve 310 by a bolt. Further, the rotation ring 160 is prevented from rotating with respect to the sleeve 310 by a knock pin 311 that engages with a notch 161 formed in the rotation ring 160. The notch 161 has a shape that is notched radially outward from the inner peripheral surface of the rotating ring 160. An annular gap between the inner peripheral surface of the rotating ring 160 and the outer peripheral surface of the sleeve 310 is sealed with an O-ring.

  The second fixed ring 170 is urged in the axial direction toward the rotating ring 160 by a spring 121 provided in the stuffing box 120. Further, the rotation of the second fixed ring 170 with respect to the stuffing box 120 is prevented by a rotation stop pin 122 that engages with a notch 171 formed in the second fixed ring 170. The notch 171 has a shape that is notched radially inward from the outer peripheral surface of the second fixed ring 170. An annular gap between the second fixed ring 170 and the stuffing box 120 (specifically, the outer peripheral surface of the portion of the second fixed ring 170 on the side outside the machine B and the inner peripheral surface of the stuffing box 120) Is sealed by an O-ring. As described above, the second fixed ring 170 is fixed to the stuffing box 120 in a state in which a certain amount of movement is allowed.

In the mechanical seal 100 configured as described above, when the rotating ring 160 rotates together with the rotating shaft 300, the end surface 162 of the rotating ring 160 on the in-machine region A side and the end surface 152 of the first fixed ring 150 on the out-of-machine region B side. And slide. Further, when the rotating ring 160 rotates, the end surface 163 on the outboard area B side of the rotating ring 160 and the end surface 172 on the inboard area A side of the second fixed ring 170 slide. Thus, the end surfaces 152 and 162 that slide relative to each other provide a seal between the in-machine region A (the radially inner region of the first stationary ring 150) and the intermediate chamber S1 that is the radially outer region of the rotating ring 160. Is done. Further, the end surfaces 163 and 172 that slide with each other seal between the intermediate chamber S <b> 1 and the region S <b> 2 that is a region radially inward of the second fixed ring 170.

  Note that the end surface 152 of the first fixed ring 150 on the outboard region B side corresponds to the tip of an annular convex portion that protrudes from the main body portion of the first fixed ring 150 toward the outboard region B side. As a result, even if sliding wear progresses over time, the end surface 152 is maintained in a polished state and the sealing performance is maintained, so that the life can be extended. Similarly, the end surface 172 on the in-machine region A side of the second fixed ring 170 corresponds to the tip of an annular convex portion that protrudes from the main body portion of the second fixed ring 170 toward the in-machine region A side. Thereby, even if sliding wear progresses with time, the end surface 172 is maintained in a polished state and the sealing performance is maintained, so that the life can be extended.

  The flange 110 is formed with a supply path 113 for supplying quenching liquid (cooling liquid) from the outside to the intermediate chamber S1. The supply path 113 communicates the outside of the flange 110 and the intermediate chamber S1, through which quenching liquid is supplied to the intermediate chamber S1 from a quenching liquid supply device (not shown) installed outside the mechanical seal 100. Is done. On the other hand, the stuffing box 120 is formed with a discharge path 123 for discharging the quenching liquid in the intermediate chamber S1 to the outside. The discharge path 123 communicates the intermediate chamber S1 with the outside of the stuffing box 120, and through this, quenching in the intermediate chamber S1 is performed by a quenching liquid discharge device (not shown) installed outside the mechanical seal 100. The liquid is discharged. As described above, the coolant is configured to flow in the region (intermediate chamber S1) on the outer peripheral surface side of the rotating ring 160, the first fixed ring 150, and the second fixed ring 170.

  Here, on the inner peripheral side of the stuffing box 120, a retaining ring 124 protruding into the intermediate chamber S1 is installed. Since the retaining ring 124 appropriately diffuses the flow of the quenching liquid in the intermediate chamber S1, cooling and lubrication of the sliding ring by the quenching liquid is promoted. The stuffing box 120 has a supply path 125 for supplying cooling water from the outside. The supply path 125 communicates with the discharge path 123 described above. The cooling water flowing through the supply path 125 is discharged from the discharge path 123 to the outside after cooling the stuffing box 120.

<Rotating ring and fixed ring>
With reference to FIGS. 1-5, the rotating ring 160, the 1st stationary ring 150, and the 2nd stationary ring 170 which concern on a present Example are demonstrated in detail.

  The first stationary ring 150 is configured to communicate from the end surface on one end side to the end surface on the other end side, and is formed with a passage serving as a flow path through which a quenching liquid (cooling liquid) flows. In the present embodiment, this passage is constituted by a communication groove 153. A plurality of the communication grooves 153 are provided at intervals in the circumferential direction. Further, the communication groove 153 is different from the notch 151 configured to engage with the pin 112, and the inside of the communication groove 153 is open. That is, the communication groove 153 is configured such that the quenching liquid contacts the entire inner wall surface. In addition, about the channel | path used as the flow path through which quenching liquid (cooling liquid) flows, you may comprise not only the communicating groove 153 but the through-hole 153a like the modification shown in FIG.4 and FIG.5. Even in this case, a plurality of through holes 153a are provided at intervals in the circumferential direction, and the quenching liquid is configured to contact the entire inner wall surface of the through hole 153a.

Similarly, the second stationary ring 170 is configured to communicate from one end side end surface to the other end side end surface, and a passage serving as a flow path through which a quenching liquid (cooling liquid) flows is formed. In the present embodiment, this passage is constituted by a communication groove 173. A plurality of the communication grooves 173 are provided at intervals in the circumferential direction. Unlike the notch 171 configured to engage the pin 122, the communication groove 173 is open inside the communication groove 173. That is, the communication groove 173 is configured such that the quenching liquid contacts the entire inner wall surface. In addition, about the channel | path used as the flow path through which quenching liquid (cooling liquid) flows, you may comprise not only the communicating groove 173 but a through-hole (not shown) similarly to the case of the said 1st stationary ring 150. FIG. Even in this case, a plurality of through holes are provided at intervals in the circumferential direction, and the quenching liquid is configured to be in contact with the entire inner wall surface of the through hole.

  An annular groove 164 is formed at the center of the outer peripheral surface of the rotating ring 160. The annular groove 164 is configured such that the quenching liquid contacts the entire inner wall surface.

<Excellent points of mechanical seal and sealing structure according to this embodiment>
According to the mechanical seal 100 and the sealing structure according to the present embodiment, the first fixed ring 150 is connected to the passage (the communication groove 153 or the through hole 153a) configured to communicate from the one end side end surface to the other end side end surface. Quenching fluid flows. Therefore, the contact area between the first stationary ring 150 and the quenching liquid can be increased. Thereby, the cooling effect of the 1st stationary ring 150 can be made high.

  Also in the second stationary ring 170, the quenching liquid flows through a passage (communication groove 173 or through hole) configured to communicate from the one end face to the other end face. Therefore, the contact area between the second stationary ring 170 and the quenching liquid can be increased. Thereby, the cooling effect of the 1st stationary ring 170 can also be made high.

  Furthermore, also in the rotating ring 160, since the quenching liquid flows through the annular groove 164, the contact area between the rotating ring 160 and the quenching liquid can be increased. Thereby, the cooling effect of the rotating ring 160 can also be enhanced.

  As described above, the cooling effect of the mechanical seal 100 can be enhanced, and the temperature rise of the mechanical seal 100 can be sufficiently suppressed. Therefore, deterioration of the mechanical seal 100 due to heat can be suppressed.

(Other)
In the above-described embodiment, both surfaces (end surfaces 162, 163) of the rotating ring 160 are sliding surfaces, and fixed rings (first fixed ring 150 and second fixed ring) are provided on both sides of the rotating ring 160, respectively. The case of the mechanical seal was described as an example. However, the mechanical seal to which the present invention is applicable is not limited to this. The present invention can be applied to various mechanical seals each including one or more rotating rings and fixed rings, such as a single-type mechanical seal including one rotating ring and one fixed ring.

DESCRIPTION OF SYMBOLS 100 Mechanical seal 110 Flange 111 Spring 112 Pin 113 Supply path 120 Stuffing box 121 Spring 122 Pin 123 Discharge path 124 Retaining ring 125 Supply path 130 Seal cover 150 First fixed ring 151 Notch 152 End face 153 Communication groove 153a Through hole 160 Rotating ring 161 Notch 162, 163 End face 164 Annular groove 170 Second fixed ring 172 End face 173 Communication groove 200 Housing 201 Shaft hole 300 Rotating shaft 310 Sleeve 311 Knock pin 320 Sleeve collar 330 Color 401 Oil seal 402 Oil seal A In-machine area B Machine Outside area S1 Intermediate room

Claims (8)

A rotating ring fixed to the rotation axis;
A fixed ring that is fixed to a housing having a shaft hole through which the rotary shaft is inserted and that slides with respect to the rotary ring;
A mechanical seal comprising:
A mechanical seal, wherein the stationary ring is configured to communicate with an end surface on one end side to an end surface on the other end side, and a passage serving as a flow path through which a coolant flows is formed.   2. The mechanical seal according to claim 1, wherein the passage is configured by a communication groove, and the coolant is in contact with the entire inner wall surface of the communication groove.   2. The mechanical seal according to claim 1, wherein the passage is configured by a through hole, and the coolant is in contact with the entire inner wall surface of the through hole.   The mechanical seal according to claim 1, 2 or 3, wherein an annular groove is formed in the center of the outer peripheral surface of the rotating ring. A rotation axis;
A housing having a shaft hole through which the rotating shaft is inserted;
A mechanical seal having a rotating ring fixed to the rotating shaft, and a fixed ring fixed to the housing and sliding with respect to the rotating ring;
In a sealing structure configured to allow cooling liquid to flow in a region on the outer peripheral surface side of the rotating ring and the stationary ring,
A sealing structure characterized in that the stationary ring is configured to communicate from one end side end surface to the other end side end surface, and a passage serving as a flow path through which a coolant flows is formed.   The sealing structure according to claim 5, wherein the passage is constituted by a communication groove, and the cooling liquid is in contact with the entire inner wall surface of the communication groove.   The sealing structure according to claim 5, wherein the passage is configured by a through hole, and the cooling liquid is in contact with the entire inner wall surface of the through hole.   The sealing structure according to claim 5, 6 or 7, wherein an annular groove is formed in the center of the outer peripheral surface of the rotating ring.

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