Patent ID: 7219877

Claim:
A ball valve apparatus, comprising: a body member having an upstream inlet, a downstream outlet, and an interior chamber; a ball member disposed in the interior chamber and rotatable about an axis with respect to the body member between first and second positions; a first passage through the ball member axially aligned with the inlet and outlet when the ball member is rotated to the first position, wherein the first passage has a downstream cross-sectional flow area in a downstream portion of the passage that is less than an upstream cross-sectional flow area in an upstream portion of the passage; a second passage extending through the ball member transversely with respect to the first passage and axially aligned with the inlet and outlet when the ball member is rotated to the second position; wherein the second passage has a cross-sectional flow area larger than the upstream cross-sectional flow area of the first passage; wherein the downstream cross-sectional flow area of the first passage is formed by a removable insert in the downstream portion of the first passage; and an inside surface of the downstream portion of the first passage and an outside surface of the removable insert are correspondingly inwardly tapered toward a downstream end of the downstream portion of the first passage to retain the removable insert against fluid flow.