A metal-to-metal seal for sealing an annular space between a well casing and a wellbore. The seal includes an inner portion and an outer portion, each portion including a central seal portion. The central seal portion has a concave shape in a de-energized state which curves towards the centerline of the seal and is capable of flexing radially outward towards surface of the annular space when energized. The central seal portion further includes at least one outer ridge extending outward away from the centerline of the seal and sealingly engages with the outer annular surface when energized.

A metal-to-metal seal for sealing an annular space between a well casing and a wellbore. The seal includes a first end, a second end, and a central seal portion. The central seal portion has a concave shape in a de-energized state which curves towards the centerline of the seal and is capable of flexing radially outward towards surface of the annular space when energized. The central seal portion further includes at least one outer ridge extending outward away from the centerline of the seal and sealingly engages with the outer annular surface when energized.

A rupture disk for use in a fluid control system includes a membrane and a compressible flange, around a perimeter of the membrane. The flange defines at least one perimetrically extending void.

A seal assembly configured to seal against a surface of a seal depressor is disclosed. The seal assembly includes a body member configured to elastically expand from an original state into an expanded state. The body member exerts a sealing pressure against the surface of the seal depressor when in the expanded state. The seal assembly also includes one or more actuation members constructed from a shape memory material having a high energy state and a low energy state. The one or more actuation members are configured to urge the body member of the seal assembly from the original state into the expanded state when the shape memory material transitions from the low energy state to the high energy state.

A metal gasket includes: a metal gasket body having, in the outer circumferential surface thereof, a recessed circumferential groove; and an elastic body. An elastic body is inserted into the circumferential groove of the gasket body; in a vertical cross-section of the metal gasket, an arc-shaped upper seal surface having an upward-facing bulge is formed on the top surface of the gasket body which contacts a material to be sealed, and an arc-shaped lower seal surface having a downward-facing bulge is formed on the bottom surface of the gasket body which contacts the material to be sealed; and an upper flat surface or an upper notched section is provided to the upper seal surface, and a lower flat surface or a lower notched section is provided to the lower seal surface.

An airfoil assembly includes first and second ceramic airfoil pieces that each have first and second platforms and a hollow airfoil section that connects the first and second platforms. First and second spars extend through, respectively, the hollow airfoil sections. A seal has a seal body that defines at least one orifice and a seal portion. The first spar extends through one of the at least one orifices and the seal portion bridges a mate face between the first platforms of the first and second ceramic airfoil pieces.

A metal O-ring is provided. The metal O-ring has a sidewall with an outer surface and an inner surface. The outer surface of the sidewall is machined to selectively thinning the thickness of the sidewall, such that the sidewall of the of the metal O-ring has a plurality of thicknesses equal to or less than a maximum thickness and equal to or more than a minimum thickness. Selectively thinning the sidewall by machining the outer surface allows for control of the elasticity of the metal O-ring. Controlling the elasticity of the metal O-ring, and potentially increasing the spring back, may provide for increased contract pressure at a sealing interface, which would facilitate sealing. The machined outer surface of the metal O-ring are generally machined to flat surfaces.

A static metal seal comprising an outer sealing layer, wherein the outer sealing layer comprises a textured surface that is configured to come into contact with the surfaces that are to be sealed, the textured surface comprising a network of depressions spaced apart from one another on the textured surface, wherein the depressions are blind, do not pass all the way through the outer sealing layer, and do not communicate with one another.

A metal sealing ring (1) for forming a metal-to-metal seal between two opposing metal surfaces. The metal sealing ring (1) comprises a tubular metal body (3) and an inlet tube (7) extending from the body (3) for introducing an internal pressure into the body (3). The body is adapted to deform under the internal pressure against each of the opposing metal surfaces to form the seal (1).

A downhole tool including an insertion member arranged to insert into and form an annular seal with a receiving member using an annular seal assembly. The seal assembly includes a compliant metal spring and a separate metal cover overlapping at least a portion of an outside of the spring, wherein the cover and spring extend radially outward from the downhole tool so as to be compressed when the insertion member is inserted within the receiving member to form an annular metal-to-metal seal between the insertion member and the receiving member. A method of coupling the downhole tool and the receiving member in a well includes inserting the insertion member of the downhole tool into the receiving member and energizing and forming an annular metal-to-metal seal by compressing the seal assembly between the insertion member and the receiving member when inserting the insertion member into the receiving member.