IMPELLER STRESS IMPROVEMENT THROUGH OVERSPEED

摘要

IMPELLER STRESS IMPROVEMENT THROUGH OVERSPEED A method for improving the capability of a body to withstand stress during rotation of the body by inducing at a selected location in the body a residual compressive stress which opposes the steady tensile stress produced by rotation. The method comprises rotating the body at a succession of increasing peak speeds in excess of the design speed to induce tolerable yielding and residual compressive stress at each location experiencing higher steady tensile stress than the selected location. The succession proceeds from the location experiencing the highest steady tensile stress above that at the selected location to the location experiencing the lowest steady tensile stress above that at the selected location. Then the body is rotated to a still higher peak speed to induce tolerable yielding and residual compressive stress at the selected location. D-16827