Patent ID: 6935369

Claim:
A high pressure gas valve for oxygen service, comprising: a valve body with a gas inlet passage; a valve seat associated with said gas inlet passage, said valve seat having an annular seat surface, said annular seat surface extending between an inner and outer border; an obturation unit movable in said valve body between a first position, wherein it is spaced from said valve seat, and a second position, wherein it is seated on said valve seat, said obturation unit having a sealing surface that is in sealing contact with said seat surface in said second position of said obturation unit; and a metallic sealing element and a synthetic sealing element co-operating to form said sealing surface, wherein said metallic sealing element forms the sealing surface around said inner border of said seat surface, and said synthetic sealing element forms said sealing surface towards said outer border of said seat surface; wherein said metallic sealing element is housed in an annular groove of said synthetic sealing element, so as to co-operate with said synthetic sealing element to form a flat composite sealing surface.