Deburring of Complex-Shaped Drilling Intersections: A Numerical Method for Modelling the Tool Path

When drilling holes, burrs are created in particular on the exit surface. Existing deburring tools and methods enable the deburring of plane exit surfaces or slightly curved cross-drilled holes. However, these tools do not meet practical requirements for deburring in the machining industry where component geometries are often complex. This paper presents a numerical method, which enables deburring of complex-shaped drilling intersections with ball-end cutters. First, the particular intersection is analysed as it defines the maximum tool diameter of the ball-end cutter. Subsequently, a three-axis tool path for ball-end cutters is generated to correlate with the intersection geometry thus enabling constant chamfering and avoiding tool collisions. The model is verified by an experiment using the material AlSi7Mg and measuring secondary burr heights and chamfer widths. Subsequently, the functionality of the model for further geometry variants is investigated

The Effect of Lean Practices on Environmental Performance: An Empirical Study

Lean production has emerged in the past decades as one of the most popular topics in business and manufacturing literature, as it is the production paradigm currently applied in many industries. This paradigm is characterized by five principles and the importance of reducing waste (muda). In the same way, the environmental performance of companies in terms of pollution prevention and use of natural resources is another widespread issue for both firms and customers. This focus on \u201cGreen manufacturing\u201d is part of one of the three pillars of Sustainable development. Lean and the so-called Green paradigm are both focused on waste reduction and several authors have studied their relationships (common points and divergences) and the synergic effects of joining these two management approaches. However, the impact of Lean practices on environmental performance is still unclear, as limited empirical research has been conducted in this field. In this chapter, a study is carried out in order to analyze the impact on environmental performance in manufacturing firms that have implemented various Lean practices. The chapter is divided in two parts. First we have conducted a review of the relevant literature in order to give a state-of-the-art general picture. The second part of the chapter has a strong empirical focus. Three case studies regarding firms that have started a Lean transformation program for at least five years are investigated in depth. Moreover, a cross-case analysis is carried out to map the possible relationships between Lean practices and particular Green performances. The general findings of the research outline that the environmental performance of the company is enhanced in the long-term after the implementation of Lean practices