An assessment of stresses in thin walled welded tubes through hole drilling and sectioning methods

Hole drilling method, which is relatively simple and fast, is one of the most popularly used semi-destructive methods of residual stress evaluation which can provide the measurement of residual stress distribution across the thickness in magnitude, direction and sense. The strains relieved by drilling a small hole of approximately 2 mm diameter are measured using special purpose strain gauges and the residual stresses present in the component are computed from the relieved strains. As a case study, the residual stresses present in aluminium alloy (AA2219) formed and welded components at various locations are presented and compared. The results are compared with the stresses computed from the deflection obtained after chemical milling and EDM.