A seal, in particular a gasket, for sealing with at least one sealing layer a gap in a housing that extends around an inner chamber of the housing. In particular, a frame seal which seals between a lower part and an upper part of the housing, for example a motor vehicle battery housing or a motor vehicle battery box housing.

A metal gasket (10) installed between a cylinder head and a cylinder block comprises at least one metal substrate (11) coated with a sealant (19) on its outer surface, and including a full bead (13) for cylinder bore hole sealing and a half bead (16) for liquid hole sealing. The half bead (16) includes: an inclined plate portion (16b) connected to a flat substrate body (11a) of the metal substrate (11) through a first bend portion (16a) and inclined with respect to the substrate body (11a); and an edge plate portion (16d) connected to the inclined plate portion (16b) through a second bend portion (16c) and inclined with respect to the inclined plate portion (16b). A radius at a convex surface of the first bend portion (16a) and a radius at a concave surface of the second bend portion (16c) are in a range of 2.0 mm to 3.5 mm.

Gaskets for sealing two mating surfaces have an inner ring positioned between two inner sealing deformable layers and an outer ring positioned exterior and concentric to the inner ring, the outer ring positioned between two outer sealing deformable layers. The two inner sealing deformable layers are configured to compress a greater amount than the two outer sealing deformable layers when a compressive force is applied. In a compressed configuration, the two inner sealing deformable layers fill in the crevices of the mating surfaces of a corroded flange connection thereby avoiding immediate maintenance for the damaged flanges. The inner and outer rings have grooves and ridges on upper and lower surfaces to retain and receive portions of the inner and outer sealing deformable layers in a sealed flange connection.

A hydrogenated NBR composition comprising 30 to 200 parts by weight of titanium oxide and 1 to 8 parts by weight of magnesium oxide, based on 100 parts by weight of hydrogenated NBR. By forming a crosslinked rubber layer of the rubber composition on a metal plate, a gasket material with excellent blister resistance, whose roll kneadability is improved without reducing the rubber strength of hydrogenated NBR, is provided. Moreover, the rubber composition is effective as a rubber raw material for use in soft metal or a high hardness hydrogenated NBR material for which kneading processing is difficult.

Seal between mutually fixed surfaces comprises a metal ring, placed between graphite layers, where sections of the metal ring to be coated with graphite have a jagged profile. Both sides of the metal ring are coated with graphite in such a way that graphite layers and the metal ring form a seamless whole. Recesses are made in the seal on both sides between graphite rings, a hole is placed in their centre.

A gasket material comprising a crosslinked fluororubber layer having a micro-hardness of 5 to 25 formed on a metal plate using a fluororubber composition comprising 30 to 70 parts by weight of carbon black having a CTAB specific surface area of 3 to 34 m.sup.2/g, and 5 to 15 parts by weight of hydrated amorphous silicon dioxide having a BET specific surface area of 35 to 220 m.sup.2/g, based on 100 parts by weight of fluororubber, wherein the total amount of carbon black and hydrated amorphous silicon dioxide is 80 parts by weight or less.

According to some embodiments, a multi-layer gasket with a non-compressible core, formed of any material that is relatively rigid and incompressible and can serve as a carrier for a gasket, and compressible layers, formed of any flowable or compressible sealing material with appropriate rheology for a particular sealing application, in the form of edge or surface coatings, is presented.

A gasket retainer that is absent sharp corners, has apertures of reasonable dimensional tolerance, and may be conveniently made by a variety of manufacturing processes. The retainer is made from thin flat springy material that readily returns to form after slight bending. Representative gasket capturing apertures are of smoothly non-convex outline with major dimension sufficiently large to allow passage of a ring shaped gasket turned on edge and minor dimension sufficiently small to engage, on approximately opposite circular segments that each engage along less than one third of a gasket circumference, a cavity or groove on the outside diameter periphery of the gasket turned flat parallel to the retainer material sheet. Fasteners may be retained by similar apertures.

A self-sealing fastener for reducing leaks between the self-sealing fastener and a substrate. The self-sealing fastener includes a shank that extends longitudinally between a first end and a second end. The shank has an outer surface. The self-sealing fastener also includes a head that extends radially outwardly from the first end of the shank. The head has an underside surface that is adjacent to the first end of the shank and a topside surface opposite the underside surface. A mastic sealant is disposed on at least one of the outer surface of the shank and the underside surface of the head to provide a water-tight seal between the self-sealing fastener and the substrate after the self-sealing fastener is installed in the substrate.

A flanged fitting includes an annular fitting flange having an annular end face. A glass liner lines a radially inner annular portion of the annular end face of the annular fitting flange. A radially outer annular portion of the annular end face of the annular fitting flange is free from the glass liner. The radially inner annular portion and the radially outer annular portion of the annular end face of the annular fitting flange define an annular gasket abutment face configured to seat a gasket thereon. An annular gasket includes an annular gasket layer. The annular gasket layer includes a radially inner annular gasket segment including a first material suitable for forming a liquid-tight seal with an opposing flange. A radially outer annular gasket segment surrounds the radially inner annular gasket segment. The radially outer annular gasket segment is fire-rated for forming a fire-rated seal with the opposing flange.