Deformable Attaching Portion for Shock-Absorbing Cover in Radioactive Material Packaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional packaging for radioactive materials faces challenges in preventing shock-absorbing cover ejection during falls, leading to potential shear failure of screws and non-compliance with regulatory requirements, such as drop tests and fire resistance, due to deformation and shifting of covers.
Innovation Solution
Incorporating a deformable area in the attaching portions of the packaging's shock-absorbing covers that can plastically deform upon impact, prioritizing screw shear resistance over screw failure, allowing for conventional tightening standards without oversizing the clearance between screws and holes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the clearance between attaching screw and clearing hole is increased to allow cover deformation during falls, then the risk of screw shear failure is reduced, but the screw head diameter becomes smaller than the clearing hole diameter requiring thrust washers exposed to bending stress
Solution Approach 1:
The patent changes the clearance parameter from a fixed small value to a variable value that increases during fall events. The deformable area allows the clearing hole to expand dynamically, providing sufficient clearance for cover deformation while maintaining proper screw head engagement during normal conditions.
Solution Approach 2:
The patent introduces a dynamic clearing hole that can change its dimensions. The deformable area in the attaching portion allows the hole to expand when subjected to impact forces during falls, adapting to the deformation needs of the cover while preventing screw shear failure.
2Reliability
If the diameter of screw heads is increased or the number of screws is multiplied to restrict cover ejection risks, then the reliability of cover attachment is improved, but the global weight of packaging increases and dimensional problems arise
Solution Approach 1:
The patent changes the geometric parameters of the attaching portion by introducing a deformable area that increases the effective clearance of the clearing hole. This allows the use of standard-sized screws without increasing their number or head diameter, while still preventing cover ejection during falls.
3Manufacturing precision
If standard clearance dimensions are used for attaching screws, then manufacturing precision is maintained, but the attaching screw is sheared in case of packaging fall on the cover
Solution Approach 1:
The patent transforms the static clearing hole into a dynamic structure with a deformable area that can expand during impact events. This allows the clearance to adapt to the deformation of the cover during falls, preventing screw shear while maintaining precise manufacturing for the initial assembly.
Solution Approach 2:
The deformable area acts as an intermediary element between the screw and the cover deformation. It absorbs the impact energy by deforming, protecting the screw from shear forces while allowing the cover to deform as needed during falls.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The deformable areas effectively prevent cover ejection and screw shear during falls, ensuring compliance with regulatory tests like the nine-meter free fall, while maintaining assembly standards and protecting screws from shear failure.
Implementation Method 1
at least one of said attaching portions has a deformable area which, in the case of an outer bias on the absorbing cover leading to a contact strain between said screwed element and the clearing hole, is designed to plastically deform
Implementation Method 2
the heat conduction means enable the heat released by the radioactive materials to be conducted towards the outside of the container
Implementation Method 3
the latter are provided to form a barrier against the neutrons emitted by the radioactive material accommodated in the cavity
Data Source
AI summary
The invention relates to a packaging for transporting and/or storing radioactive materials, comprising a packaging body extending along a longitudinal direction, and further including at least one shock-absorbing cover mounted on one of both longitudinally opposite ends of the packaging body, the absorbing cover comprising attaching portions (44) on said packaging body, each attaching portion defining a clearing hole (58) through which an element (24) screwed in the packaging body passes. According to the invention, the attaching portion (44) has a deformable area (54) which, in the case of an outer bias on the absorbing cover leading to a contact strain between the screwed element (24) and the clearing hole (58), is designed to plastically deform.