Abstract: Methods and systems for retaining bonnets on blowout preventers. In one embodiment, a blowout preventer includes a hollow body, a ram disposed in a ram cavity of the hollow body, and a bonnet coupled to the hollow body. The bonnet is fastened to the hollow body with threaded fasteners, which include a threaded shaft and a threaded nut. The shaft and the nut include mating interrupted threads with threaded portions and longitudinal unthreaded portions that can be rotationally aligned so that threaded portions of each of the shaft and the nut are aligned with unthreaded portions of the other of the shaft and the nut to allow the threaded shaft to be received within the threaded nut and the threaded nut to then be rotated with respect to the threaded shaft to cause the threaded portions of the threaded nut to engage the threaded portions of the threaded shaft.

Abstract: Methods and systems for retaining bonnets on blowout preventers. In one embodiment, a blowout preventer includes a hollow body, a ram disposed in a ram cavity of the hollow body, and a bonnet coupled to the hollow body. The bonnet is fastened to the hollow body with threaded fasteners, which include a threaded shaft and a threaded nut. The shaft and the nut include mating interrupted threads with threaded portions and longitudinal unthreaded portions that can be rotationally aligned so that threaded portions of each of the shaft and the nut are aligned with unthreaded portions of the other of the shaft and the nut to allow the threaded shaft to be received within the threaded nut and the threaded nut to then be rotated with respect to the threaded shaft to cause the threaded portions of the threaded nut to engage the threaded portions of the threaded shaft.

Abstract: An apparatus includes a blowout preventer housing including a bore extending therethrough and a cavity intersecting the bore. The apparatus further includes grooves in the outer profile of the blowout preventer housing, the grooves being on opposite sides of the cavity.

Abstract: An apparatus includes a blowout preventer housing including a bore extending therethrough and a cavity intersecting the bore. The apparatus further includes grooves in the outer profile of the blowout preventer housing, the grooves being on opposite sides of the cavity.

Abstract: The present invention provides a “third-axis” leveling block for use with an archery sight. The third-axis leveling block holds an archery sighting device (e.g., a scope or a pin sight) as know in the art. The leveling block adjusts the position of the sight in two axes by means of cams. One of the cams adjusts the sighting device to the archer's preferred cant. The other cam adjusts the angle of the sighting device with respect to the bow to keep the archer's cant consistent when the bow is raised or lowered for shooting at targets at any elevation, above, below, or on the same level as the archer.