Experimental Strain Investigation of Bolt Torque Effect in Mechanically Fastened Joints

Abstract

In this study, a different issue of mechanical engineering interests is determined for threaded fastened joints. A series of photoelastic experiments were performed to determine the maximum strains for the holes in a tensile flat plate subjected to bolt-nut loads. Pertinent strain distributions were examined to determine the roll of the torques on the bolts in mini mizing the strain; hence stress concentration. The experimental determination of maximum strains is needed as a way to validate future theoretical and numerical results, and provide a valuable aid to their application. The emphasis of this paper is on deformation. The results indicate that strains can decrease significantly with the increase of the bolt's pre-load.

In this study, a different issue of mechanical engineering interests is determined for threaded fastened joints. A series of photoelastic experiments were performed to determine the maximum strains for the holes in a tensile flat plate subjected to bolt-nut loads. Pertinent strain distributions were examined to determine the roll of the torques on the bolts in mini mizing the strain; hence stress concentration. The experimental determination of maximum strains is needed as a way to validate future theoretical and numerical results, and provide a valuable aid to their application. The emphasis of this paper is on deformation. The results indicate that strains can decrease significantly with the increase of the bolt's pre-load.

Cite this paper

N. Younis, "Experimental Strain Investigation of Bolt Torque Effect in Mechanically Fastened Joints,"*Engineering*, Vol. 4 No. 7, 2012, pp. 359-367. doi: 10.4236/eng.2012.47047.

N. Younis, "Experimental Strain Investigation of Bolt Torque Effect in Mechanically Fastened Joints,"

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