A Virtual Machining Model for Sustainability Analysis

Sustainability has become a very significant research topic since it impacts many different manufacturing industries. The adoption of sustainable manufacturing practices and technologies offers industry a cost effective route to improve economic, environmental, and social performance. As a major manufacturing process, the machining system plays an important role for sustainable manufacturing on the factory floor. Therefore, technologies for monitoring, analyzing, evaluating, and optimizing the sustainability impact of machining systems are critical for decision makers. Modeling and Simulation (M&S) can be an effective tool for success of sustainable manufacturing through its ability to predict the effect of implementing a new facility, process without interrupting real production. This paper introduces a methodology that provides a traditional virtual Numerical Control (NC) machining model with a new capability – to quantitatively analyze the environmental impact of machining system based on Life Cycle Assessment (LCA). The objective of the methodology is to analyze the sustainability impacts of machining process and determine a better plan for improving the sustainable performance of machining system in a virtual environment before work orders are released to the shop floor. Testing different scenarios with simulation models ensures the best setting option available can be chosen. The virtual NC model provides the necessary data for this assessment. In this paper, a list of environmental impact indicators and their metrics has been identified, and modeling elements for sustainable machining have been discussed. Inputs and outputs of the virtual machining model for sustainable machining are described. A case study to experiment the proposed methodology is discussed. INTRODUCTION This section describes the concept of sustainable manufacturing, sustainable machining, Modeling and Simulation (M&S), and Life Cycle Assessment (LCA). Current problems in industry are also addressed. Sustainable Manufacturing Sustainable development has become an important part of approaches to integrate economic, environmental, and social aspects. The Department of Commerce recently identified sustainable manufacturing as one of its high-priority performance goals, defining sustainable manufacturing as the “creation of manufactured products that use processes that minimize negative environmental impacts, conserve energy and natural resources, are safe for employees, communities, and consumers and are economically sound [1].” As such, sustainability related issues such as energy consumption, emissions and other environmental impact issues are becoming a more integrated part of operational and long-term planning decisions in manufacturing [2]. Machining is a major manufacturing operation and it involves a number of sustainability factors that have a big potential for environmental impact. These factors include tool life, usage of coolant and lubricant, waste chips and energy consumption. Therefore, the analysis of machining systems and optimization of these input factors (controls and constraints) and outputs (objective functions) has significant implication for sustainable manufacturing. It has been observed that the relationship between machining technologies and environmental impact remains insufficiently discussed and the environmental impact due to this manufacturing activity has been little evaluated [3]. Currently, there is no ideal method that can analyze the