Abstract: A valve stem seal comprising a cylindrical stem-sealing membrane and a membrane supporting flange. The membrane has a corrugated profile which defines one or more loop-shaped channels bounded by contact surfaces on a radially inner face and each channel is inclined at 5.degree.-10.degree. with respect to a plane perpendicular to the longitudinal axis. The channels form a labyrinth seal for any fluid leaking along the outer surface of the stem. A support bearing for the stem is provided on the membrane supporting flange.

Abstract: A static seal comprising an envelope of chemically resistant PTFE and a metallic packing ring within the envelope shaped to form cells. The cells may be filled with an inert gas under pressure so that increased loads on the seal may be cushioned.

Abstract: A floating gate valve seat has an integral static seal comprising a convex arcuate limb 9 and a projecting tip 25 on the limb arranged to contact a seat pocket surface 12 and place the limb in flexing stress to effect a seal at the tip 25. A set-back stop surface 15 on the valve seat limits the compression of the seal and the axial movement and the valve seat 7.

Abstract: According to a first aspect of the invention a metal sealing ring has a hollow cross section which is open at its radially innermost side and has limbs generally directed towards the radially innermost side. The radially outermost region of the cross section is provided with reinforcement so as to locally increase its hoop strength. According to a second aspect of the invention, a hollow self-energising metal sealing ring and a seating for the sealing ring are provided with complimentary radial cross sectional shapes which cooperate to limit the rotation of the sealing ring cross section when axially compressed.As can be seen in FIG. 11, the surfaces 45 are tangential to the convex arcuate contact lines C, in the relaxed state of the seal ring. During compression these surfaces remain substantially tangential to the regions C, as the limbs flex.

Abstract: A metallic sealing ring which in radial cross-section is hollow and of sinuous profile having axial end faces sinuously curved so as each to define an axially outward facing deep peripheral groove, the interior of the ring profile being in communication with the exterior thereof.

Abstract: A static seal capable of accommodating significant lack of flatness comprises a PTFE envelope 1, within which is a filling 5 consisting of wound or nested turns of thin metal strip 7 perforated to provide resiliance in the direction of their width. Individual turns can move or collapse to different extents, thereby accommodating lack of flatness of surfaces to be sealed. Turns of fluid-impervious material may be distributed among the turns of perforated strip.

Abstract: A hollow metallic sealing ring of low-load, self-energizing, static kind is characterized in that in radial cross-section it is of modified parabolic form with convergent margins (M) with a radial width, in its relaxed state, which is equal to substantially 7/8ths (0.875) of its maximum length (A) measured in the direction parallel to the axis of the ring.

Abstract: A metal valve seat for a butterfly valve or ball valve and has the form of an apertured disc with a radially outward part (4A) by which it is securable to a valve body and a radially inward dished part (4B) which projects laterally around the disc aperture. The valve seat is characterized in that the disc part (4B) is formed circumferentially with a plurality of web-connected fingers which have a radially inward surface of varying generative radius. The invention also consists in a butterfly valve or a ball valve incorporating one or a pair of such metal valve seats.

Abstract: A heat safe ring seal comprises a metallic hollow ring (1) of uniform material thickness and radially inwardly facing channel-shaped radial profile. The walls of the channel adjacent their free ends are curved towards each other so as to form axially outwardly facing grooves (1a) which each accommodate and shield a concentric ring (2) of PTFE or elastomeric material.

Abstract: A composite annular seal for a rotary ball valve or ball joint comprises a sealing ring (C) of low friction material intended to engage the ball (2), a first metal ring (A) of which part of one face is adapted resiliently to engage and conform with part of the surface of the sealing ring (C) while a radially more inward part of the face is adapted to engage and conform with the curvature of the ball (2), a second metal ring (B) which supports the first metal ring (A), having a radially outer part which overlaps the radially outer part of the sealing ring (C) and the radially outer part of the first metal ring (A) and of which a part is adapted to be in area contact with a part of the first metal ring (A), and a layer (D) of soft non-metallic material bonded to the axially outward surface of the second metal ring (B) for separating that part of the second metal ring (B) from the part of the housing (1) into which the seal is intended to be installed.

Abstract: A cylinder head gasket for wet liner internal combustion engine comprises a pair of outer metal plates (1) and a central plate (2) made of stainless steel within a hardness range of 130-170 VPN of which the part surrounding each cylinder bore opening is formed with at least one circumferential corrugation (2a) which, in that region, increases the separation distance between the outer metal plates.

Abstract: An annular seal primarily for use in preventing leakage of liquids and gases along rotating and/or reciprocating shafts where the latter pass through support structures such as plates and casings. The annular seal (3) is characterized in that it has the shape of a hat with an axially apertured crown (3a) and an adjoining brim (3b) each comprised of a plurality of alternately interleaved layers of sheet metal (M) and of a non-metallic material (G) selected from expanded graphite, carbon, natural or synthetic rubber or bonded fibrous material. Such a seal can also be used in the sealing of a butterfly valve when in its closed position.

Abstract: A ring seal primarily for sealing static mating faces comprises an annular jacket (1), which may be made of low friction plastics material, having a channel of part-elliptical radial profile. Within the channel there is accommodated an energizing spring (2) in the form of a ring of channel-shaped radial profile, there being a gap between a part (M) of the spring ring (2) and the channel to allow movement of the spring ring relative to the jacket when the ring seal is brought into use. The spring ring (2) is made from a transversely folded strip of metal with segmented side edges which is formed into a circle and then has its ends secured together.

Abstract: A ring seal of the kind comprising an annular jacket (1) of relatively yieldable material with a channel containing an energizing spring to impart resilience thereto, is characterized in that the channel is of substantially part-elliptical profile and contains a partly spaced spring ring (2) of channel shaped radial profile. The spring ring comprises a pair of metal rings (2a, 2b) which have axial slits and are secured together around their outer periphery prior to insertion in the jacket channel. Additionally the spring ring may have a plane circular ring welded thereto in a central diametric plane and to this latter ring there may be secured a dual component cylindrical protection ring having its axis coincident with the axis of the ring seal.

Abstract: A gasket is particularly intended for sealing the joint between the cylinder block (4), the cylinder head and a liner (3) inserted in the cylinder block. Such a gasket (G) is of annular shape and comprises a varying thickness radial corrugated part (1) with an annular skirt (2) depending from its outside periphery. The part (1) is intended to be accommodated in an end recess (3a) in the cylinder liner which also has a radially outer recess (3b) which accommodates the skirt (2) so as accurately to center the gasket around the cylinder bore.

Abstract: A gasket for sealing the joint between the cylinder block and the cylinder head of a dry liner internal combustion engine comprises two outer metal plates (1) and a central composite metal plate (2) disposed between the two outer plates. The gasket is particularly characterized in that between cylinder bore openings in the gasket at least one shim (3,4) is secured between one side of the central composite metal plate and the adjacent outer metal plate, in order to prevent loss of load on the gasket in those areas and resultant gas leakage. Similarly at least one shim (5) may be located in like manner between the central plate and an outer plate at corners of the gasket.

Abstract: A gasket for sealing a joint between the cylinder block and the cylinder head of a wet liner internal combustion engine comprises a pair of outer metal plates (1) having outwardly directed corrugations formed therein away from cylinder bore openings. A composite metal spacer plate (2) is disposed between the plates (1) and has a central soft metal layer and hard metal surface layers bonded or integral therewith. Characteristically the metal spacer plate (2) extends into proximity with the individual cylinder bore openings and is formed adjacent these openings on each axial face with circumferential serrations (2a) of V-shaped radial profile; the thickness of the spacer plate measured over the peaks of the serrations before the gasket is installed is somewhat greater than that of the remainder of the spacer plate while the thickness measured between the troughs of the serrations is significantly less than that of the remainder of the spacer plate.

Abstract: A gasket for sealing the joint between the cylinder head and exhaust manifold of an internal combustion engine comprises a flat sheet metal base layer (1) having an opening or openings (A) therein corresponding to the number of cylinder head and exhaust manifold ports around which a seal is required, a second layer in the form of a radially corrugated metal annulus or annuli (2) applied to the base layer (1) around the or each opening (A), with the radially inner parts of the or each annulus (2g) spaced apart from the base layer (1) around the or each opening (A), and a sheet metal layer (D) which effectively increases the thickness of the base layer (1) in regions of the base layer which surround securing stud apertures (C) therein. The layer (D) may be formed by folding over the base layer sheet (1) or alternatively it may be a separately attached sheet metal layer.

Abstract: A gasket for sealing the joint between the cylinder block and the cylinder head of a wet liner internal combustion engine comprising a pair of outer metal plates (1), a metal spacer plate (2) between the two outer plates and comprised of an essential soft metal layer and hard metal surface layers there being fitted around each cylinder bore opening a metal washer (7) formed on each axial face with circumferential serrations (7a) of V-shaped profile. The thickness of the washer (7) measured over the peaks of the corrugations (7a) is somewhat greater than that of the spacer plate (2) whereas the thickness measured between the troughs of the serrations (7a) is significantly less than that of the spacer plate (2).

Abstract: A gasket for sealing the joint between the cylinder block and the cylinder head of wet liner internal combustion engine formed a pair of outer metal plates, and a composite metal spacer plate disposed between the two outer plates. Incorporated between the outer metal plates and around each cylinder bore opening is a washer having on each face circumferential serrations of V-shaped profile.