Valve assembly

A valve assembly, comprising:

• a valve body having an exterior surface and an interior surface, the interior surface defining:
• a first port and a second port with a ball receiving cavity therebetween;
• a cylindrical access channel extending from the exterior surface to the ball receiving cavity, the access channel comprising an alternating series of radial keyways and lug restraints, the lug restraints extending inward relative to the radial keyways and overhanging a coupling recess, the coupling recess comprising a continuous circumferential cavity in the inner surface of the cylindrical access channel that is accessible by radial keyways on either side of each lug restraint, the cylindrical access channel forming a continuous sidewall around and radially enclosing the radial keyways and the access channel;
• a ball positioned within the ball receiving cavity, and the ball having a stem;
• and
• a bonnet having a cylindrical body with an exterior surface and an interior surface, the cylindrical body being sized to closely fit within the access channel of the valve body, the interior surface defining a stem channel in which the stem of the ball is positioned, and comprising at least one lug that extends radially from the exterior surface of the cylindrical body, the at least one lug being configured and sized to be accepted by the radial keyways and to be housed within the coupling recess when the cylindrical body is twisted, in either direction, so that the at least one lug is out of register with the radial keyways and retained by the lug restraints.