| 摘要 |
A tiedown system for releasably securing a cask of the type used to transport radioactive waste to a cradle assembly that is mounted onto the deck of a trailer is disclosed herein. The tiedown system includes a trunnion securing assembly for each of the opposing trunnions of the cask, as well as a compliant linkage connected between the trunnion securing assemblies and the cradle assembly for biasing the cask trunnions toward the cradle assembly with a tiedown force that remains substantially constant despite angular displacements of the trunnions which may occur when the trailer traverses rough or uneven roads. The compliant linkage includes a pair of inverted L-shaped levers for each of the opposing trunnion securing assemblies, as well as a tie-bar which is both axially and rotatably movable within a lower portion of the cradle assembly. The end portions of the tie-bar are threaded, one end of each of the levers is pivotally connected to one of the trunnion securing assemblies, while the other end is pivotally connected to an end portion of the tie-bar by way of a threaded coupling. Each of the levers is in turn pivotally connected to the walls of the cradle and configured so as to convert vertical displacements of the cask trunnions caused by rough or uneven roads into horizontal displacements which in turn move the horizontally-oriented tie-bar to and fro, thereby avoiding the generation of localized stresses between the cask trunnions, the cradle assembly and the trailer deck and frame while maintaining a substantially constant tiedown force between the cask and the cradle. The compliant linkage also allows the trunnion securing assemblies to be quickly connected or disconnected from the cask trunnions.
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