Fatigue Analysis of a Rack Tool to Increase Milling Productivity

In recent years, the automotive industry has had remarkable technological growth. Organizations strive to have in their processes more advanced technologies that allow them to create a competitive advantage over others within the same field. The spline rolling and the threading process have evolved in line with the significant demand for quality products from major automakers in the automotive industry. Product consumers of the automotive industry demand quality at low prices, which results in the need to maximize resources for auto-parts manufacturing. In this work, an improvement in the performance of a spline forming rack from 5,000 to 25,000 pieces is reported. A conceptual design of such rack was developed in which the geometry of the tooth was modified; then, employing a finite element analysis, using ANSYS Version R19.2., the average fatigue life of 25,000 cycles was obtained. Finite element results were validated by on-site experimental tests using the Digital Image Correlation (DIC) technique. Finally, the tooling was manufactured and put into operation, reaching 32,785 rolled parts; with this performance, the initial goal of at least 25,000 parts was surpassed. Subsequently, three forming racks were fabricated, from which an average yield of 30,269 rolled parts was obtained. Keywords: Fatigue, Digital Image Correlation technique (DIC), Finite element analysis, Rolling process.