Quarter-turn plug valve having adjustable bonnet and tapered raised valve seats

A valve comprising:

• A. a metallic body, having:
• 1. a body cavity defining an inverted frustoconical wall;
• 2. a through-flow passage;
• 3. a port on each of the opposite sides of the frustoconical wall of said body cavity, said port communicating with said body cavity and said through-flow passage;
• 4. a first seat on said body;
• B. a metal plug, having:
• 1. an inverted frustoconical wall surface, parallel to the frustoconical wall of said body cavity and extending into said body cavity across the through-flow passage of said valve body;
• 2. a transversely-extending through-flow passage;
• C. a valve stem, having a threaded portion at its lower end and a handle portion at its upper end;
• D. a second and third metal seat, surrounding the port on the opposite sides of said cavity, said second and third seats:
• 1. extending from the wall of said body cavity toward said plug, and
• 2. being tapered to conform with the taper of the frustoconical surface of said plug;
• E. an infinitely adjustable, vertically-elongated bonnet, having:
• 1. a recess at its lower end;
• 2. a threaded bore directly above said recess for engagement of the threads of the valve stem;
• 3. said bonnet being freely rotatable around the threads of said valve stem and in contact with said first seat on said valve body, said threaded bore coacting with said threads of said valve stem, to move said valve stem through an infinite range of vertical adjustment and bring the plug into seated position against said second and third metal seats in closed, no-flow position;
• F. a bonnet flange, surrounding said bonnet;
• G. bolt means for clamping said bonnet flange in fixed position on said valve body and for securing said bonnet and said valve stem and plug in proper rotational position throughout a wide range of opening and closing torques;
• H. a handle, mounted on the upper end of said valve stem with its long axis extending transversely to the axis of the valve body's through-flow passage when the plug is in the closed, no-flow position and which may be rotated a quarter-turn:
• 1. to bring the long axis of the handle into alignment with the through-flow passage of the valve body;
• 2. to move said plug with a vertically-upward and rotational movement out of engagement with said metals seats;
• and
• 3. to bring the transversely-extending through-flow passage of said plug into registry with the ports of said through-flow passage of said valve body in open-flow position.