Abstract: A firesafe bidirectional floating ball valve comprising: a housing; first and second annular seats that hold between them a ball that is rotatable to open and close the valve to fluid flow; an annular spring on one side of the ball that operates to seal both of the seats to the ball; and an annular ridge coaxial with the first seat; wherein with the valve closed, net pressure on the ball in a direction from the second fluid flow port to the first fluid flow port operates to displace the ball and apply force to the first annular seat that closes a narrow clearance space between the ball and the first annular seat.

Abstract: A firesafe bidirectional floating ball valve comprising: a housing having a cavity and first and second fluid flow ports through which fluid flows selectively in either direction from the first to the second or the second to the first fluid ports when the valve is open; a ball formed having a through hole for passage of fluid housed in the cavity and rotatable to open the valve and allow fluid flow through the fluid ports and cavity and to close the valve and block fluid flow through the fluid ports and cavity; first and second annular seats that hold and seal the ball between them; and an annular ridge coaxial with the first seat and having an end surface spaced from the first seat by a narrow clearance space; wherein with the valve closed net pressure on the ball in a direction from the second fluid flow port to the first fluid flow port operates to displace the ball and apply force to the first annular seat that closes the clearance space.