An earlier paper presented a non-linear analysis of hydraulic re-autofrettage following initial hydraulic autofrettage and low temperature heat soak. The benefits from such a sequence derive almost exclusively from the mitigation of Bauschinger effect. As a result yielding during re-autofrettage occurs in the near-bore region. In this paper hydraulic re-autofrettage following initial swage autofrettage and heat soak is analyzed. The benefits in this case derive mainly from the adjustment of stress fields within the wall of the tube, close to the original elastic-plastic interface created during the swage process. Bauschinger effect mitigation is a second order effect. This procedure is the subject of a recently-submitted patent application. The procedure can produce significant improvements in initial re-yield pressure and in safe maximum pressure as defined by additional permanent strain. An increase in fatigue crack growth lifetime is also predicted. At higher re-autofrettage pressures OD residual hoop stresses increase significantly.

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