Anti-extrusion seal element

Abstract

A sealing assembly for effecting the sealing of an annulus between two telescopically related tubular conduits, of the type employed in subterranean wells, is achieved by utilizing annular seal backup elements dieformed from a knitted wire mesh by two successive dieforming steps. In the first dieforming, the knitted mesh backup element is formed to an external diameter equal to or preferably exceeding the maximum diameter that will be required for the backup member to assume when expanded into engagement with the outer wall of the annulus to be sealed. The second dieforming operation reduces the external diameter of the annular knitted mesh seal backup element to a dimension less than the outer wall of the annulus to be sealed, thus permitting convenient assembly and run-in of the sealing assemblage. The two step dieforming operation significantly reduces the amount of axial compressive force required to expand the sealing elements and the seal backup members to their sealed position.

Dependencies are inferred from the claim text.