Abstract: In metal-on-metal sealing structures, the sealing criteria employed for high pressure liquid fuel does not work when sealing gaseous fuels. A technique for sealing a gaseous fuel between gaseous fuel conduits in an internal combustion engine includes forming a contact band between two surfaces of a sealing structure between a first conduit and a second conduit. A width of the contact band is at least equal to the larger of a minimum contact pressure width where contact pressure is at least equal to a predetermined minimum contact pressure; and a minimum yield zone width where at least one of the two surfaces have plastically deformed.

Abstract: In metal-on-metal sealing structures, the sealing criteria employed for high pressure liquid fuel does not work when sealing gaseous fuels. An improved method for sealing a gaseous fuel between gaseous fuel conduits in an internal combustion engine comprises forming a contact band between two surfaces of a sealing structure between a first conduit and a second conduit. A width of the contact band is at least equal to the larger of a minimum contact pressure width where contact pressure is at least equal to a predetermined minimum contact pressure; and a minimum yield zone width where at least one of the two surfaces have plastically deformed.