EFFECT BY PIERCING PLUG O.D.-W.T. RATIO ON WORKING TAPER LONGITUDINAL CRACK DEVELOPMENT

The paper involves an introduction to the experiments on the relationship between the plug working taper longitudinal crack development and the variation of the plug O.D.-W.T. ratio and an analysis of the conditions for the said crack development. Based on the experiments, a conclusion can be made that proper reduction of the said ratio will bring about a better supression of the crack, thus a longer service life of the plug.