Ball valve

In a ball valve having a valve body chamber with a floating ball valve member mounted therein for movement between open and closed positions, and an annular recess about a flow passage in the valve body adjacent the flow chamber defining an outer circumferential surface and an adjacent planar shoulder extending in a generally radial direction;

• an improved one piece annular metal seat fitting within said annular recess about said flow passage adapted for contacting the adjacent spherical surface of the floating ball valve member, said metal seat comprising:
• a body portion of a generally uniform thickness extending in a generally radial direction in opposed relation to the adjacent planar shoulder and defining an inner low pressure lip about its inner circumference contacting the adjacent spherical surface of the floating ball member in sealing relation during the entire operation of said ball valve, said body portion of said metal seat acting in a manner similar to a Belleville spring with said inner lip being spaced from said opposed shoulder under low pressure operation and said body portion sealing in metal to metal relation against said shoulder adjacent the corner of said recess formed at the juncture of said shoulder and said outer circumferential surface thereof;
• and
• a bearing portion integrally connected to said body portion and extending therefrom in a direction generally parallel to the longitudinal axis of the flow passage, said bearing portion having a substantially conforming seat surface adjacent the spherical surface of the floating ball member, said conforming seat surface being spaced from said spherical surface under low pressure operation of said ball valve a distance less than the spacing of said lip from said shoulder and contacting said spherical surface in bearing relation under high pressure operation of said valve prior to contact of said lip against said shoulder.