PERFORMANCE OF CONTAINER FASTENERS SUBJECTED TO STATIC AND DYNAMIC WITHDRAWAL
Abstract:
The performance of 15 different types of metal fasteners was studied in simulated container applications. The specimens were assembled at 20 percent moisture content and subjected to indoor storage under controlled conditions of temperature and relative humidity, and to outdoor storage. Impact and static withdrawal forces were applied after various periods of storage. The instrumentation used to measure maximum loads and time duration of impacts is fully described. Analyses of variance are used to evaluate the data. Helically threaded nails and nylon-coated staples retained their initial resistance to withdrawal after a year of storage at 73 F. and 50 percent relative humidity, while other fasteners exhibited a marked decrease in withdrawal resistance 2 weeks after driving. Helically threaded nails exhibited the best performance after 1 year on an outdoor exposure fence. Some fastener coatings offered resistance to corrosion but did not improve resistance to withdrawal. In general, dynamic withdrawal loads were significantly higher than corresponding static-withdrawal values.