| 摘要 |
<p>A ball valve (10) has a stem (28) to rotate a ball member (20) with a lower key or lug (29) received within a slot or opening (26) forming a keyway in the ball member (20). As shown particularly in (Figures 2 and 3), relieved or cutaway surfaces (52, 54, 56) are provided between lug (29) and the outer spherical surface (24) of ball member (20) so that a torque exerted by rotation of the stem (28) contacts surfaces (34, 36) of the slot (26) along opposed corners (48) which are spaced a distance T1 from the outer spherical surface (24) of ball valve member (20) thereby removing or minimizing any stress concentrations adjacent outer spherical surface (24).</p> |
