Seal arrangement and method of sealing
View Patent ↗A seal arrangement includes a body having at least two walls defining a cavity, the walls are engagable with at least one structure through expansion of the body, and graphite is sealingly engaged with the body and the structure and resiliently compressively maintained within the cavity by the at least one structure.
1. An annular seal arrangement comprising:
a body supported on a tapered annular outer surface of a first structure, the body having at least two walls defining a cavity open in a radially outward direction, the body being radially outwardly expandable through movement over the tapered annular surface of the first structure, each of the at least two walls including an inclined terminal end portion configured to contact an annular inner surface of at least one second structure through outward radial expansion of the body; and
expandable graphite arranged in the cavity and being constrained by the at least two walls, the expandable graphite being configured to sealingly contact the annular surface of the at least one second structure and be resiliently compressively maintained within the cavity by a compressive force between the body and the at least one structure applied to the expandable graphite, and wherein the expandable graphite is capable of thermal expansion to generate loading against the at least one second structure.
2. The seal arrangement of claim 1 , wherein a compressed resilient member other than the expandable graphite is configured to maintain compressive loads on the graphite.
3. The seal arrangement of claim 1 , wherein the expandable graphite is capable of deforming into sealing engagement with the at least one second structure.
4. The seal arrangement of claim 3 , wherein the expandable graphite is capable of plastic deformation.
5. The seal arrangement of claim 1 , wherein engagement between the body and the at least one second structure prevents the expandable graphite from escaping from the cavity.
6. The seal arrangement of claim 5 , wherein a volume of the cavity is capable of increasing when the body is engaged with the at least one second structure.
7. The seal arrangement of claim 1 , wherein the expandable graphite is capable of volumetric expansion in a range of about 50% to 200%.
8. The seal arrangement of claim 1 , wherein the expandable graphite sealably engages with the first and second structures.
9. The seal arrangement of claim 1 , wherein the expandable graphite is in the form of a plurality of slabs.
10. The seal arrangement of claim 9 , wherein the plurality of slabs are stacked perimetrically adjacent to one another.
11. The seal arrangement of claim 9 , wherein the plurality of slabs have an initial shape that is substantially trapezoidal in cross section.
12. The seal arrangement of claim 1 , wherein the at least two walls define a U-shape cross-section of the body.