Ultra-high vacuum metallic seal
View Patent ↗A metallic seal design that reduces manufacturing costs by minimizing production steps and also lowers the sealing force by incorporating a thin-wall, high height/width ratio annular column. The seal has two horizontal ribs which constrain the thin-wall column from unstable buckling to thereby reduce or eliminate the tendency of the sealing dams to become inclined to sealing flange surfaces.
1. A metallic seal for sealing axially facing surfaces comprising an annular column portion surrounding a central axis and having at opposite axial ends respective sealing dams for engaging the axially facing surfaces to be sealed, and at least two ribs extending radially from the annular column portion, the ribs being axially spaced apart from each other and each pair of ribs defining therebetween an annular recess, the ribs being spaced at a pitch having a length generally corresponding to an axial length of the metallic seal divided by the number of ribs.
2. A metallic seal as set forth in claim 1 , wherein the recess is generally U-shape, and the ribs extend perpendicular to the central axis.
3. A metallic seal as set forth in claim 1 , wherein the annular column portion extends axially beyond respective axially outermost ribs forming recesses that correspond in shape to one half of the annular recess.
4. A metallic seal as set forth in claim 1 , wherein the annular column portion has a height dimension along the central axis, and wherein the annular column portion has a radially inner surface and a radially outer surface, the inner and outer surfaces defining a column width therebetween, the column width being substantially uniform along the height of the annular column portion.
5. A metallic seal as set forth in claim 1 , wherein a height/width ratio of the column portion is about seven or greater.
6. A metallic seal as set forth in claim 1 , wherein at least one rib has a thickness dimension in the axial direction that is about equal to or greater than a radial column width.
7. A metallic seal as set forth in claim 1 , wherein the respective sealing dams are in axial alignment with the annular column portion.
8. A metallic seal as set forth in claim 1 , wherein at least one of the sealing dams has a radial width between about 0.008 and about 0.016 inches.
9. A metallic seal assembly comprising a seal retainer and at least one seal as set forth in claim 1 .