A SIMPLE METHOD FOR DETERMINATION OF RESIDUAL STRESSES USING DOUBLE-HOLE DRILLING TECHNIQUE

Document Type : Original Article

Authors

1 Graduate Student and Assoc. Prof. in Mech. Design Dept., Faculty of Eng. and Tech., Mataria, Helwan University, Cairo.

2 Prof. Gen. Chief of Mech. and Elasticity Dept., Military Technical College.

Abstract

One of the most common semi-distructive methods for determination of re-sidual stresses in plates is the drilling hole method. In this method, a strain rosette or a set of strain gauges are usually used to measure the relaxed strains induced due to drilling of a central hole. The present work *atroduces a new simple method for determination of residual stresses
in unigxially stressed plates using double hole technique. Optimum dimen-sions for hole diameter and hole spacing, associated with a specific strain-gauge length, are determined. A constant relating the residual stress and the relaxed strain in a plate is obtained. Three different plate materials are considered; steel, laminated brass and aluminum. An experimental work is done to verify the theoretical analysis. For the stated plate materials, the experimental and theoretical results are in a good agreement.