Patent ID: 7661371

Claim:
A manway system comprising: a base; a lid for engaging the base, the lid defining an aperture having an aperture seat and an aperture neck, wherein the neck is narrower than the seat; a bolt pivotally secured to the base such that the bolt is moveable from a locked position to an unlocked position, wherein a portion of the bolt passes through the aperture neck into the aperture seat when the bolt is moved from the unlocked position to the locked position; and a collar attached to the bolt such that the collar is seatable within the aperture seat when the bolt is in the locked position, wherein the collar includes an outer surface that fits within the aperture seat and presents a width greater than a width of the aperture neck, thereby preventing the collar from passing through the aperture neck, and wherein the collar includes a tapered component for guiding the collar into the aperture seat, wherein the tapered component is a chamfered rim of the collar, wherein the chamfered rim includes an annular sloping surface extending inwardly from the outer surface of the collar, and wherein the collar is defined by an annular wall presenting the outer surface, a threaded inner surface, and a chamfered rim with a tapered surface sloping from the outer surface toward the inner surface.