Energy metrics for product assembly equipment and processes

Abstract A key factor deciding the capacity to increase the sustainability of final products is the energy efficiency. The energy embodied in a product is an aggregation of all of the energy embodied in the products' components and subsystems, expended through its manufacturing processes and logistical activities. Currently, accurate estimation of this energy metric is hindered due to the unavailability of energy use data traceable to individual processes and equipment associated with the product's assembly. In this paper, we propose using minimally-required energy to compute energy efficiency of a product assembly process. Based on the proposed approach, efficiency metrics established on the process, product, material and equipment characteristics have been presented at the assembly activity and equipment level. A case study has been presented for a hybrid laser welding process to demonstrate the computational methods used to arrive at these efficiency metrics. Major contributions of this paper are the metrics development and exemplifying the metrics through an actual assembly process (hybrid laser welding) case study. We will explain how these metrics can provide industries with a capability to identify opportunities to improve their sustainability performance across their assembly processes.

[1]  P. W. Fuerschbach.  Measurement and prediction of energy transfer efficiency in laser beam welding , 1996 .

[2]  Horace Herring,et al.  Energy efficiency—a critical view , 2006 .

[3]  M. Hauschild,et al.  Methodology for systematic analysis and improvement of manufacturing unit process life-cycle inventory (UPLCI)—CO2PE! initiative (cooperative effort on process emissions in manufacturing). Part 1: Methodology description , 2011, The International Journal of Life Cycle Assessment.

[4]  John N. DuPont,et al.  Thermal efficiency of arc welding processes , 1995 .

[5]  Jami J. Shah,et al.  Neutral definition and recognition of assembly features for legacy systems reverse engineering , 2009, DAC 2009.

[6]  S. Standard.  GUIDE TO THE EXPRESSION OF UNCERTAINTY IN MEASUREMENT , 2006 .

[7]  S. Ryding.  ISO 14042 Environmental management • Life cycle assessment • life cycle impact assessment , 1999 .

[8]  Blaine Lilly,et al.  Mechanical Assemblies: their Design, Manufacture, and Role in Product Development , 2013 .

[9]  Sudarsan Rachuri,et al.  A Model for Capturing Product Assembly Information , 2006, J. Comput. Inf. Sci. Eng..

[10]  Claudio Comoglio,et al.  The use of indicators and the role of environmental management systems for environmental performances improvement: a survey on ISO 14001 certified companies in the automotive sector , 2012 .

[11]  G. A. Knorovsky,et al.  A study of melting efficiency in plasma arc and gas tungsten arc welding : a method for selecting optimal weld schedules to minimize net heat input is derived frm calorimetric measuremts , 1991 .

[12]  Rachel Hilliard,et al.  Environmental performance and practice across sectors: methodology and preliminary results , 2011 .

[13]  Nick Collings,et al.  Efficiency of tungsten-inert-gas arcs in very-high-speed welding , 1979 .

[14]  Wim Dewulf,et al.  Methodology for systematic analysis and improvement of manufacturing unit process life cycle inventory (UPLCI) Part 1: Methodology Description , 2011 .

[15]  Eugen Cicala,et al.  The use of exploratory experimental designs combined with thermal numerical modelling to obtain a predictive tool for hybrid laser/MIG welding and coating processes , 2011 .

[16]  Barbara T. Fichman.  Annual Energy Review 2011 , 2012 .

[17]  John W. Sutherland,et al.  Material flows and environmental impacts of manufacturing systems via aggregated input–output models , 2007 .

[18]  Steven R Schmid Kalpakjian,et al.  Manufacturing Engineering and Technology , 1991 .

[19]  Claudio Boer,et al.  The incoming global technological and industrial revolution towards competitive sustainable manufacturing , 2008 .

[20]  J. Goldak,et al.  A new finite element model for welding heat sources , 1984 .