Measurement of residual stresses using the deep hole method

The deep hole method for measuring the distribution of residual stresses through the thickness of thick-section engineering components is described. The method relies on the measurement of changes in diameter of a hole drilled through the component. Analyses are presented to determine the residual stresses from the measured strains. Experiments were performed on a heat treated steel block and a circumferentially butt-welded steel pipe in the as-welded and post-weld heat treated conditions. The measured residual stress distributions are presented and the results are discussed in terms of the likely errors.