Expanding hollow metal rings
View Patent ↗A sealing device that may expand more planar dimensions due to internal thermal expansion of a filler material. The sealing material is of a composition such that when desired environment temperatures and internal actuating pressures are reached, the sealing materials undergoes a permanent deformation. For metallic compounds, this permanent deformation occurs when the material enters the plastic deformation phase. Polymers, and other materials, may be using a sealing mechanism depending on the temperatures and corrosivity of the use. Internal pressures are generated by either rapid thermal expansion or material phase change and may include either liquid or solid to gas phase change, or in the gaseous state with significant pressure generation in accordance with the gas laws. Sealing material thickness and material composition may be used to selectively control geometric expansion of the seal such that expansion is limited to a specific facing and or geometric plane.
1. A thermally expansive closed three dimensional structure operable at a selected temperature range comprising:
a plurality of substantially rigid walls;
at least one deformable metal wall with respect to said rigid walls at said selected temperature range, said at least one deformable metal wall having a deformed orientation and a non-deformed orientation;
a sealed void space internal to said structure, said void space impinging upon at least one of said deformable metal walls with respect to said rigid walls; and
a fluid sealed within said void space, said fluid being selected to function as a perfect gas within said selected temperature range, wherein said fluid is present within said void space when said at least one deformable metal wall is in the non-deformed orientation, wherein in the deformed orientation said fluid contacts said at least one deformable metal wall and wherein said at least one deformable metal wall has a surface that makes up part of a seal upon engaging a rigid inner wall.
2. A thermally expansion structure according to claim 1 which expands irreversibly.
3. A thermally expansive structure according to claim 1 wherein said sealable void space is sealed to entrap said fluid.
4. A thermally expansive structure according to claim 1 which is a ring having a void between inner and outer walls of said ring.
5. A thermally expansive structure according to claim 4 wherein at least a part of the said outer wall is deformable.
6. A thermally expansive structure according to claim 4 wherein at least a part of said inner wall is deformable.
7. A thermally expansive structure according to claim 1 which is in the form of a cylinder and at least one deformable wall is an end.
8. A thermally expansive structure according to claim 1 which is in the form of a face seal wherein at least one deformable side is on a face.
9. A thermally expansive closed three dimensional structure operable at a selected temperature range to function as a modulating valve or shutoff valve comprising:
a plurality of substantially rigid walls;
at least one deformable wall with respect to said rigid walls at said selected temperature range, wherein said at least one metal deformable wall has a deformed orientation and a non-deformed orientation, wherein said at least one metal deformable wall defines a passageway therethrough in the non-deformed orientation;
a sealed void space internal to said structure, said void space impinging upon at least one of said deformable metal walls with respect to said rigid walls;
a fluid sealed within said void space, said fluid being selected to function as a perfect gas within said selected temperature range; and
a process fluid flowing through said passageway of said at least one metal deformable wall when said at least one deformable metal wall is in the non-deformed orientation, wherein reorientation of said at least one deformable metal wall to the deformed orientation effects closure of said passageway and reduction or stoppage of the flow of said process fluid.