Experimental results of single screw mechanical tests: a follow-up to SAND2005-6036.

Lee, Sandwook ; Lee, Kenneth L. ; Korellis, John S. ; McFadden, Sam X.

Sandia National Laboratories

关键词: Modifications;    Orientation;    Weapon 80;    Fasteners;    Friction Factor;   

DOI  :  10.2172/890602
RP-ID  :  SAND2006-3751
RP-ID  :  AC04-94AL85000
RP-ID  :  890602

美国|英语

来源: UNT Digital Library

【 摘 要 】

The work reported here was conducted to address issues raised regarding mechanical testing of attachment screws described in SAND2005-6036, as well as to increase the understanding of screw behavior through additional testing. Efforts were made to evaluate fixture modifications and address issues of interest, including: fabrication of 45{sup o} test fixtures, measurement of the frictional load from the angled fixture guide, employment of electromechanical displacement transducers, development of a single-shear test, and study the affect of thread start orientation on single-shear behavior. A286 and 302HQ, No.10-32 socket-head cap screws were tested having orientations with respect to the primary loading axis of 0{sup 0}, 45{sup o}, 60{sup o}, 75{sup o} and 90{sup o} at stroke speeds 0,001 and 10 in/sec. The frictional load resulting from the angled screw fixture guide was insignificant. Load-displacement curves of A286 screws did not show a minimum value in displacement to failure (DTF) for 60{sup o} shear tests. Tests of 302HQ screws did not produce a consistent trend in DTF with load angle. The effect of displacement rate on DTF became larger as shear angle increased for both A286 and 302HQ screws.