Sealing arrangements
View Patent ↗Sealing elements locate an annular seal plate in an annular recess. The sealing elements are each in the form of a ring or a segment of a ring comprising a channel-shaped cross-section, the mouth of which receives the seal plate. Each sealing element is thus interposed between the seal plate and a corresponding part of a machine element such as a turbine casing in which the recesses are provided. The sealing elements protect the casing against wear caused by movement of the seal plate relative to the casing. The sealing element is of relatively low cost and is expected to be replaced when the apparatus of which it forms part is serviced.
1. A sealing arrangement between first and second machine elements, comprising:
a) a first recess in the first machine element;
b) a second recess in the second machine element, and confronting the first recess across a gap;
c) first and second sealing elements each comprising sheet material having a channel-shaped cross-section located in the first and second annular recesses respectively; and
d) a seal plate bridging the gap and received edgewise in the channel shapes of the first and second sealing elements;
e) the channel-shaped cross-section of the first and second sealing elements comprising a closed end, an open end and a neck portion part way between the closed end and the open end, the neck portion being narrower than the closed end and the open end and sized to receive the seal plate.
2. The sealing arrangement according to claim 1 , wherein at least one of the first and second sealing elements is formed of a resilient material and the neck portion of the channel shape is sized to grip the seal plate.
3. The sealing arrangement according to claim 1 , wherein:
the first recess is annular and opens radially inwards;
the second recess is annular and opens radially outwards;
the channel shapes of the first and second sealing elements extend around the circumferential extents of the first and second recesses respectively;
the seal plate is disk-shaped;
the open end of the first sealing element opens radially inwards to receive an outer edge of the seal plate; and
the open end of the second sealing element opens radially outwards to receive an inner edge of the seal plate.
4. The sealing arrangement according to claim 1 , wherein:
the first recess is annular and opens towards a first axial direction;
the second recess is annular and opens towards a second axial direction opposing the first axial direction;
the channel shapes of the first and second sealing elements extend around the circumferential extents of the first and second recesses respectively;
the seal plate is cylindrical;
the open end of the first sealing element receives a first end of the seal plate; and
the open end of the second sealing element receives a second end of the seal plate.
5. The sealing arrangement according to claim 1 , wherein the first and second machine elements comprise two parts of a pressurized housing.
6. The sealing arrangement according to claim 5 , wherein the pressurized housing comprises a casing of a turbomachine.
7. The sealing arrangement according to claim 1 , wherein the first and second sealing elements comprise walls of substantially constant thickness that define the channel-shaped cross-section.
8. The combination of a recess in a machine element and a sealing element located in the recess for sealingly locating a seal plate in the recess, the sealing element being channel-shaped in cross-section, the channel-shaped cross-section comprising a closed end, an open end and a neck portion part way between the closed end and the open end, the neck portion being narrower than the closed end and the open end and sized to receive the seal plate.
9. The combination according to claim 8 , wherein the channel is convergent from the closed end to the neck portion and divergent from the neck portion to the open end of the channel.
10. The combination according to claim 9 , wherein the sealing element is formed of a resilient material and the neck portion of the channel shape is sized to grip the seal plate.
11. The combination according to claim 8 , wherein the machine element comprises part of a pressurized housing.
12. The combination according to claim 11 , wherein the pressurized housing comprises a casing of a turbomachine.
13. The combination according to claim 8 , wherein the sealing element comprises walls of substantially constant thickness that define the channel-shaped cross-section.
14. A sealing arrangement between first and second machine elements, comprising:
a) a first recess in the first machine element;
b) a second recess in the second machine element, and confronting the first recess across a gap;
c) first and second sealing elements each comprising sheet material having a channel-shaped cross-section located in the first and second annular recesses respectively; and
d) a seal plate bridging the gap and received edgewise in the channel shapes of the first and second sealing elements;
e) the channel-shaped cross-section of the first and second sealing elements comprising a closed end, an open end and a narrower neck portion part way between the closed end and the open end, the neck portion being sized to receive the seal plate, the channel shape of at least one of the first and second sealing elements being convergent from the closed end to the neck portion and divergent from the neck portion to the open end.
15. The sealing arrangement according to claim 14 , wherein the shape of at least one of the first and second recesses is divergent towards its open end.
16. The sealing arrangement according to claim 15 , wherein the shape of at least one of the first and second recesses is divergent towards its open end from an inner neck port.
17. A sealing arrangement between first and second machine elements, comprising:
a) a first annular recess in the first machine element and opening radially inwards;
b) a second annular recess in the second machine element and opening radially outwards, and confronting the first recess across a gap;
c) first and second sealing elements each comprising sheet material having a channel-shaped cross-section located in the first and second annular recesses respectively, the channel shapes of the first and second sealing elements extending around the circumferential extents of the first and second recesses respectively; and
d) a disk-shaped seal plate bridging the gap and received edgewise in the channel shapes of the first and second sealing elements, the open end of the first sealing element opening radially inwards to receive an outer edge of the seal plate, and the open end of the second sealing element opening radially outwards to receive an inner edge of the seal plate;
e) the channel-shaped cross-section of the first and second sealing elements comprising a closed end, an open end and a narrower neck portion part way between the closed end and the open end, the neck portion being sized to receive the seal plate, each of the seal plates, the first sealing element and the second sealing element comprising a ring formed in two generally semicircular halves.
18. The sealing arrangement according to claim 17 , wherein a junction between two adjacent parts of the seal plate has a stepped configuration such that the two parts overlap.