Shaft sealing device and rotary machine

Patent metadata

Field	Value
Publication number	US-12247490-B2
Application number	US-202318681261-A
Country	US
Kind code	B2
Filing date	Feb 27, 2023
Priority date	Mar 4, 2022
Publication date	Mar 11, 2025
Grant date	Mar 11, 2025

Abstract

This shaft sealing device comprises: a housing that has a storage groove; a seal body stored in the storage groove; and a projected part that projects from one of the housing and the seal body toward the other in the storage groove in an axial direction. The seal body divides an annular space into a high-pressure region on a first side in the axial direction and a low-pressure region on a second side in the axial direction. The housing has a connection part that connects the low-pressure region with the inside of the storage groove. The projected part divides a portion between an opposite surface and a low-pressure-side lateral surface of the seal body into a first space on the radially outer side and a second space on the radially inner side. The connection part connects the first space with the low-pressure region.

First claim

The invention claimed is:

1. A shaft sealing device comprising:
a housing which is disposed on an outer side in a radial direction at an interval with respect to a rotor being rotatable around a central axis, extends in a circumferential direction around the central axis, and has an accommodating groove that is recessed to the outer side in the radial direction;
a sealing body which has a plurality of thin plates laminated in the circumferential direction, in which an outer peripheral end portion on the outer side in the radial direction is accommodated in the accommodating groove, and in which an inner peripheral end portion on an inner side in the radial direction extends from the housing to the inner side in the radial direction to come into slidable contact with an outer peripheral surface of the rotor; and
a convex portion which protrudes in an axial direction in which the central axis extends from any one of the housing and the sealing body toward the other in the accommodating groove,
wherein the sealing body partitions an annular space between the rotor and the housing into a high-pressure region on a first side in the axial direction and a low-pressure region on a second side in the axial direction,
the sealing body has a sealing body low-pressure-side side surface facing the second side in the axial direction within the accommodating groove,
the housing has
a facing surface which forms a part of the accommodating groove and faces the sealing body low-pressure-side side surface at an interval in the axial direction, and
a communication portion which allows the low-pressure region and an inside of the accommodating groove to communicate with each other,

the convex portion is formed on the facing surface or the sealing body low-pressure-side side surface, and partitions a space between the facing surface and the sealing body low-pressure-side side surface into a first space portion on the outer side in the radial direction and a second space portion on the inner side in the radial direction, and
the communication portion allows the first space portion and the low-pressure region to communicate with each other.

2. The shaft sealing device according to claim 1 , further comprising:
a side plate which is disposed on the first side in the axial direction with respect to the sealing body,
wherein the sealing body has a sealing body high-pressure side surface facing the first side in the axial direction,
the side plate is disposed along the sealing body high-pressure side surface in the accommodating groove, and
the convex portion is disposed on the outer side in the radial direction, which is closer to an end portion of the side plate on the inner side in the radial direction.

3. The shaft sealing device according to claim 1 ,
wherein the convex portion is formed on the facing surface to protrude to the first side in the axial direction, and abuts against the sealing body low-pressure-side side surface to restrict movement of the sealing body to the second side in the axial direction.

4. The shaft sealing device according to claim 1 ,
wherein the communication portion has at least one communication hole formed such that one end thereof is open at the facing surface and the other end is open at an outer surface of the housing that faces the low-pressure region.

5. The shaft sealing device according to claim 4 ,
wherein a plurality of communication holes are formed while being spaced apart from each other in the circumferential direction.

6. The shaft sealing device according to claim 1 ,
wherein the communication portion has at least one communication groove formed to pass therethrough the convex portion in the radial direction and allow the first space portion and the second space portion to communicate with each other.

7. The shaft sealing device according to claim 6 ,
wherein a plurality of communication grooves are formed while being spaced apart from each other in the circumferential direction.

8. The shaft sealing device according to claim 1 , further comprising:
an outer peripheral convex portion which is disposed on the outer side in the radial direction with respect to the convex portion and protrudes from any one of the facing surface and the sealing body low-pressure-side side surface to the other in the axial direction.

9. The shaft sealing device according to claim 1 ,
wherein the sealing body has a main body portion, and a head portion which protrudes from the main body portion to both sides in the axial direction on the outer side in the radial direction than the sealing body low-pressure-side side surface,
the accommodating groove has a main body accommodating portion in which the main body portion is accommodated, and a head accommodating portion which is formed on the outer side in the radial direction with respect to the main body accommodating portion to accommodate the head portion therein, and
the head accommodating portion has an outer peripheral contact surface that faces the outer side in the radial direction and allows the head portion to come into contact from the outer side in the radial direction.

10. The shaft sealing device according to claim 1 , further comprising:
a biasing member which is disposed inside the accommodating groove to bias the sealing body in the radial direction with respect to the housing.

11. The shaft sealing device according to claim 1 ,
wherein at least one of the housing and the sealing body is formed of a plurality of divided bodies in the circumferential direction, and
the shaft sealing device further includes a seam convex portion which is formed on at least one of the facing surface and the sealing body low-pressure-side side surface in a region overlapping with a seam of adjacent divided bodies in the circumferential direction when viewed from the axial direction, protrudes from any one of the facing surface and the sealing body low-pressure-side side surface toward the other in the axial direction, and extends in the radial direction along the seam.

12. A rotary machine comprising the shaft sealing device according to claim 1 .

Assignees

• Mitsubishi Heavy Ind Ltd

Inventors

• Ozaki Kohei
• Kawano Masaya
• Yoshida Azumi
• Okumura Shintaro
• FURUSHO Tatsuro
• Nishimoto Shin

Classifications

• F16J15/50

  between relatively-movable members, by means of a sealing without relatively-moving surfaces, e.g. fluid-tight sealings for transmitting motion through a wall · CPC title

• F01D25/183

  Sealing means · CPC title

• F01D5/025

  Fixing blade carrying members on shafts (attachment of a member on a shaft in general F16D1/06; for non-positive displacement pumps F04D29/00) · CPC title

• F05D2240/581

  Double or plural piston ring arrangements, i.e. two or more piston rings · CPC title

• F16J15/3272

  the rings having a break or opening, e.g. to enable mounting on a shaft otherwise than from a shaft end · CPC title