Six Sigma for improving aesthetic defects in aluminum profiles facility

Abstract

Purpose This paper aims to develop a quality plan to detect aesthetic defects in extruded aluminum profiles before the fabrication stage based on the Six Sigma improvement methodology in an aluminum facility. These defects are hard to be detected at the fabrication stage. It is also hard to be fixed in the site. Design/methodology/approach The research methodology utilized the DMAIC framework (define, measure, analyze, improve and control). The methodology relies on statistical analysis (histogram, control charts and Pareto) and field work (observations, focus groups and interviews). Findings The process shows significant improvement in aesthetic defect reduction that aids in reaching a Four Sigma quality level. Practical implications Aluminum fabrication is known to be vulnerable for many types of defects such as scratches and debris on work surface. In addition, post-fabrication defects may also occur due to improper coating caused by chemical imbalance, blocked filters or blocked sprays. Originality/value The main contribution of this research is to demonstrate the use of DMAIC framework to reduce the aluminum aesthetic defects that reach the end customer. The Six Sigma methodology is a well-known quality improvement framework that relies heavily on quantitative data. More precisely, it is widely used to control defects in quantities such as weights, heights, etc. In this research, it has been used to control qualitative data (aesthetic). This will enable objective decisions for facility management rather than subjective.

A case study on implementing Lean Six Sigma: DMAIC methodology in aluminum profiles extrusion process

“…The internal dimension (X1) of the product's corner section revealed a reduction in DPMO from 536804 to 185795, sigma level increased from 1.4 to 2.4 and the process yield improved from 46% to 81% and there was a profit improvement rate of 75.6% per 1,000 kg of aluminum. Hadidi et al (2017) conducted a DMAIC-based study to develop a quality plan for detecting aesthetic defects in extruded aluminum profiles before being fabricated. The study employed different statistical tools including PARETO, histograms, Ishikawa diagrams and control charting and field work observations and focus groups in its phases.…”

“…Hadidi et al. (2017) conducted a DMAIC-based study to develop a quality plan for detecting aesthetic defects in extruded aluminum profiles before being fabricated.…”

“…The reason for this is the difficulties of measurements and evaluations of perceived quality and customer satisfaction in case of services (Munteanu, 2017). In metal industries, dealing with precious materials especially in aluminum manufacturing, LSS plays a significant role toward improvements and variation minimization which in turn impacts the cost to a sharp decline (Hadidi et al, 2017). All over the world, there are many success stories in manufacturing industries attributed to the implementation of LSS, for example, Ingersoll Rand made such success utilizing DMAIC approach and six sigma tools resulting in reducing defects to 70% and improved the sigma level from 0.5 to 3.53 which impacted customer satisfaction tremendously.…”

“…The reason for this is the difficulties of measurements and evaluations of perceived quality and customer satisfaction in case of services (Munteanu, 2017). In metal industries, dealing with precious materials especially in aluminum manufacturing, LSS plays a significant role toward improvements and variation minimization which in turn impacts the cost to a sharp decline (Hadidi et al. , 2017).…”