Articles 

Analysis of Hex Cap Fasteners Revealed Dimensional Related Failure Causatio

2011-02-23

Performance of fasteners relies on several factors including the intended design load, metallurgical properties associated with a given grade and geometry. For a given size fastener, these are several grades from which an architect or engineer may select for a given load capacity. Considerations when selecting a particular fastener commonly include but are not limited to the environment, expected life, cost and more importantly the in service shear and tensile loads. Higher grade fasteners used in more critical applications where failures could result in loss of life or substantial property damage have full size test requirements. One such procedure is the wedge test discussed in ASTM F 606 “Standard Test Methods for Determining the Mechanical Properties of Externally Threaded Fasteners, Washers and Rivets”. This test method in part analyzes the designed radius of curvature in the shank to head radius.