Article

Characterizing Productivity of a 4kw CO2 Laser Cutting System for 0.25” Mild Steel Using Central Composite Methodology

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Abstract

Laser cutting of sheet metal has be- come an economically viable method of production through advances in technology. Evidence of advances in laser technology has been thoroughly documented as research published in professional literature. The most relevant research available in professional literature was used to provide a basis and context for the research documented in this paper, wherein much of that research was directed toward improving the quality of cuts made by laser devices. Accordingly, researchers conducted this study to investigate increasing throughput of laser cutting operations where the quality of cuts produced by a new 4kW CO2 laser exhibited an acceptable surface roughness. For purposes of this study, “acceptable” surface roughness was a contractually negotiated parameter of < 18?m. Surface roughness of < 18?m was a parameter of primary importance to and industry benchmark for metal fabricators. This study was conducted in an operational manufacturing environment and was based on the design and analysis of a 2 4 full factorial characterization experiment later projected to a 3 4 central composite design with response surface methodology for further characterization. Input (independent) variables of the study included feed rate, power, frequency, and gas pressure while the output (dependent) variable was surface roughness. As this was an “applied” rather than empirical study, many other possible combinations of variables and settings for those variables were not considered due to expense and the discretion/interest of management at the host manufacturing facility. Results of this study indicated that use of the most advanced laser cutting technology commercially available did not guarantee production of cut quality at < 18?m in an operational manufacturing environment. Conclusions drawn from the study were that 1.) Suggested set- tings for process variables provided by the vendor of the laser cutting system were not valid in the host manufacturer’s production environment, 2.) Cut quality was highly sensitive to changes in the input variables – particularly gas purity, and 3.) Interpretation of a response surface generated as part of the experiment design indicated an expansion of the experimental space (i.e., collection of more experimental material at levels/settings not included in the original or projected design) may be warranted.

Keywords: manufacturing|machine tools|materials and processes|quality|research methods

How to Cite:

Cadorette, M. L. & Walker, H. F., (2006) “Characterizing Productivity of a 4kw CO2 Laser Cutting System for 0.25” Mild Steel Using Central Composite Methodology”, Journal of Industrial Technology 22(2).