Patent ID: 9243711
Filing Date: 2016-01-26
CPC Classification: E21B,F16J,F16L

Claim Text:
1. A pressure-energized seal for sealing between first and second members, comprising: a metal seal having an axis, a first end portion for sealingly engaging a first member seal surface, and a second end portion for sealingly engaging a second member seal surface; the metal seal having a sidewall extending between the first and second end portions, the sidewall having interior and exterior sides, the sidewall having at least one inner fold and at least one outer fold between the first and second end portions, the inner fold having an inner diameter closer to the axis than an inner diameter of the outer fold, each of the folds having axially spaced apart flanks and an axial gap therebetween, the flanks of each of the folds being parallel with each other and perpendicular to the axis while there is no pressure differential between the interior and exterior sides of the seal, the gap between the flanks of the inner fold having an open outer end on the exterior side of the seal, and the gap between the flanks of the outer fold having an open inner end on the interior side of the seal; wherein internal fluid pressure greater than external fluid pressure acting on the seal urges the flanks of the outer fold to flex away from each other to enhance sealing of at least one of the end portions; internal fluid pressure greater than external fluid pressure acting on the seal also urges the flanks of the inner fold to flex toward each other; external fluid pressure greater than internal fluid pressure acting on the seal urges the flanks of the inner fold to flex away from each other to enhance sealing of at least one of the end portions; external fluid pressure greater than internal fluid pressure acting on the seal also urges the flanks of the outer fold to flex toward each other; an outer spacer being positioned in the gap of the inner fold in contact with both of the flanks of the inner fold to limit movement of the flanks of the inner fold toward each other when the internal fluid pressure is greater than the external fluid pressure; and wherein the outer spacer is configured and positioned so as to be in non sealing engagement with the flanks of the inner fold.