Abstract: A fuel assembly includes a plurality of fuel rods comprising fissile material, a plurality of guide tubes interspersed amongst the fuel rods, an upper end fitting connected with upper ends of guide tubes, and a lower end fitting. End plugs are connected with the lower ends of the guide tubes. The end plugs have threaded male shafts extending from the lower ends of the guide tubes which pass through openings of the lower end fitting. Female lock nuts are threaded onto the threaded male shafts of the end plugs and lock with the lower end fitting to secure the lower end fitting to the lower ends of the guide tubes. The female lock nuts suitably have locking portions that are outwardly deformed into recesses of the lower end fitting to lock the lock nuts in place after tightening.

Abstract: A twist lock insertion and twist release extraction type spring cotter pin having one primary straight end extremity to be inserted through an aperture in a structural element and its opposite adjacent free end extremity consisting of a series of arcuate curves allowing them to partially rotate or counter rotate about the surface of said structural element. And, commensurate with this, an easy grasp handle all made of spring steel type wire. The method of said designed invention allows for a new definition of utility for a spring cotter pin of this particular unique function the extraordinary characteristics of which demonstrate a locking spring pins basic need for a revision of often ignored operational safety features without compromising the new standards it has attained for ease of function yet maintaining its overall convenience, reliability and durability.

Abstract: An apparatus for mounting and retaining a component on a shaft including a tubular shaft having an aperture extending radially therein, and a retaining ring adapted to fit over the shaft, including a center post wherein the center post is positioned within the aperture on the shaft when the retaining ring is assembled thereon.

Abstract: An adapter ring which screws onto a gas tank fill fitting to cover the standard threads on the fitting and provided customized non-standard threads to prevent suppliers without matching fill hose couplings from connecting their supply hose outlet fittings to the fill fittings of tanks which they are not authorized to use. The adapter rings are fastened in place with a thread damaging member which will damage the threads on the fill fitting if there is an attempt to unscrew the adapter ring.

Abstract: An apparatus for preventing the rotation of a nut with respect to a threa shaft, one version suitable for use on a plain threaded shaft and another version suitable for use on a threaded shaft having an axial keyway of rectangular cross section. The apparatus consists of a slotted and grooved nut and a tanged snap ring. The nut has radial slots across a face, and a circumferential groove which intersects the bottom of the slots. The snap ring fits over the nut within the circumferential groove, the tang extending down through the nut and engaging with the threaded shaft.