Patent ID: 7171981

Claim:
A flow control valve, comprising: a valve housing including a valve chamber; the valve chamber having a channel with a first inner diameter; the valve housing including first and second restrictive ends of the valve chamber forming first and second valve seats, the restrictive ends formed by openings having restrictive dimensions at opposite downstream and upstream positions of the chamber, respectively; the valve housing formed of a first elongate part comprising one of the restrictive ends and substantially all structure forming the first inner diameter, a second part having a length shorter than the first elongate part, the second part comprising the other of the restrictive ends; a ball having a second diameter substantially smaller than the first diameter and larger than the restrictive dimensions, the ball being held in the valve chamber by the first and second restrictive ends, wherein the downstream restrictive end comprises an annular valve seat at the first end; an internal seam between the first and second parts at one of the first and second ends, the seam forming a connection between the first and second parts of the valve housing, wherein the seam forms an intersection between the first and second parts; the intersection of the first and second parts being at a location on the first part adjoining the channel, the channel having the first inner diameter at the location, the intersection extending radially away from the channel and forming a step that has a smooth inner surface having a third inner diameter greater than the first inner diameter; and the second part having a smooth outer surface complimentary to the third inner diameter, the smooth outer surface axially received in the first part and forming the intersection, the intersection of the first and second parts being at a location on the second part radially overlying one of the restrictive ends of the valve housing.