Patent ID: 8365769

Claim:
A ball valve for threaded connection to a check valve having a male thread and a stem head configured for mating with a surface of a ball when the check valve is closed, comprising: a valve housing having a first fluid end and a second component receiving end, the valve housing containing the ball rotatable for selectively passing fluid through the valve housing and between the first fluid end and the second component receiving end; a valve body stem hub secured to the valve housing for receiving a stem to rotate the ball; a flange member secured to and extending radially outward from the valve housing and including a stop surface thereon positioned radially outward of the valve housing and supporting a first seal for sealing with the ball, the stop surface being positioned between an outer surface of the ball and a second seal positioned between the flange member and the check valve; a stop ring positioned outward of the valve housing and engageable with the stop surface on the flange member; and a coupling axially connected to the stop ring, the coupling rotatable with respect to the valve housing and the flange member, the coupling including female threads for engagement with the male threads on the check valve, the coupling female threads having a thread diameter less than a minimum diameter of the stop surface, such that rotation of the coupling onto the check valve forces the stop ring into engagement with the stop surface, the coupling female threads being opposite the stop ring with respect to the stop surface.