Application of Quality Improvement Techniques to the Powder Coat Process Joan Burtner, Chris Durre & Nikki Smith Department of Mechanical and Industrial Engineering Mercer University, Macon, GA

The Six Sigma Approach in the Business Community Six Sigma - a comprehensive system for achieving, sustaining and maximizing business success Drivers a close understanding of customer needs, disciplined use of facts, data, and statistical analysis diligent attention to managing, improving, and reinventing the business process IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Benefits of the Six Sigma Approach cost reduction productivity improvement market-share growth customer retention cycle-time reduction defect reduction culture change product/service development IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

The Six Sigma Philosophy Designed to foster data-driven management decisions The Three C’s common metrics “constant” communication culture change IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Selection Criteria for Six Sigma Improvement Projects There is a gap between current and desired/needed performance. The cause of the problem is not clearly understood. The solution isn’t predetermined, nor is the optimal solution apparent. IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

School of Engineering Senior Design Course Two semester course required for graduation with a bachelor’s degree in engineering or industrial management Student Teams Two or three students Often interdisciplinary Management Senior design course instructor Departmental technical advisor Client – internal or external IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Presenter: Dr. Joan Burtner, Mercer University Paint Cell Project Interdisciplinary team Industrial management Industrial engineering Technical advisor - Joan Burtner External client Georgia manufacturer Practices Six Sigma philosophy IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Powder Coat Process Overview Material - powdered paint Two basic application methods Part is lowered into a fluidized bed of the powder, which is electrostatically charged Powdered paint is electrostatically charged and sprayed onto the part Curing Part placed in an oven - powder particles melt and form a continuous film IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Presenter: Dr. Joan Burtner, Mercer University Powder Coat Equipment Spray Gun Corona charging guns -electric power used to generate the electrostatic charge Tribot charging guns - electrostatic charge generated by friction between the powder and the gun barrel “Bell” charging guns -powder charged by being "flung" from the perimeter of the "bell IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Powder Coat Facility Typical Spray Booth Courtesy: www.thefabricator.com Accessed March 12, 2004 IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Presenter: Dr. Joan Burtner, Mercer University Quality Issues Surface preparation Operators Training Skill Coverage Color change Cleanliness/ contamination IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Presenter: Dr. Joan Burtner, Mercer University Six Sigma Methodology Define Measure Analyze Improve Control Project Scope D-M-A IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Preliminary Process Map Load Wash Dry Paint Cure Rework Accept Unload IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Paint Cell Process Matrix Process Step # Input Measure System C/U Type Output Load 4 Wash Dry 2 Drying oven Visual inspection C Dry panel Paint 6 Cure Unload 1 Rework IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Key Customer Requirements Minimal paint thickness Even coverage Scratch-free parts IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Preliminary Data Collection Student teams Observer Recorder Random sampling 75 observations for control charts Collection sheet variables determined by client IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Revised Data Collection Student teams Observer – voltage, temperature, etc Thickness gauge operator Thickness gauge recorder Revised data collection form Limited variables – panel, color, hook, 5 locations Larger cells for recording data IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Cause and Effect Matrix # Process Step Process Input Paint Thickness Even Coverage Damage Free Total Customer Imp 7 Customer Imp 9 Customer Imp 10 1 Load Hook 3* 3 78** 2 Conveyor 78 Spray Gun 9 154 4 Cure Temp 58 * Correlation values 0, 1, 3, 9 **Sample calculation 7*3+9*3+10*3=78 IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Control Charting Deliverables Target Factor - paint thickness Data collection plan Documentation of plan as standard operating procedure Control chart training materials Control charts of baseline data IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Control Charting Locations Factor - paint thickness 5 locations Repeated measures 25 samples for baseline chart North West Middle East South IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Control Charting Sample Preliminary Range not in control IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Control Charting Sample Results - Revised Range in control Xbar not in control IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Presenter: Dr. Joan Burtner, Mercer University Designed Experiments Dependent variable - paint thickness Factor 1 - location Factor 2 - shift Statistical software package - Minitab IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Failure Modes and Effects Analysis (FMEA) Techniques 48 process steps selected for investigation 4 experts polled Operators Management Ratings entered into basic FMEA worksheet RPNs calculated Process steps ranked by RPN (high to low) IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Failure Modes and Effects Analysis - Category Ratings 1 Severity of Effect (10-1) Hazardous without warning Hazardous with warning Loss of primary function Reduced primary function performance Loss of secondary function Reduced secondary function performance Minor defect noticed by most customers Minor defect noticed by some customers Minor defect noticed by discriminating customers No effect IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Failure Modes and Effects Analysis - Category Ratings 2 Likelihood of Occurrence 9 Very High: Almost inevitable 7 High: repeated failures 4 Moderate: Occasional failures 2 Low: Relatively few failures 1 Remote: Failure is unlikely IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Failure Modes and Effects Analysis - Category Ratings 3 Ability to Detect (10-1) Cannot detect Very remote chance of detection Remote chance of detection Very low chance of detection Low chance of detection Moderately high chance of detection High chance of detection Very high chance of detection Almost certain detection IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Risk Priority Number Example Calculations Paint Material – accident or transport failure Potential Failure Effect Lack of paint consistency Severity of Effect rating 4 Potential Cause Dropped powder Likelihood of Occurrence rating 3 Current Control Lifting procedures Ability to Detect rating 3 Severity*Likelihood*Detection = 36 = RPN IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Failure Modes and Effects Analysis Results Ratings ranged from 300s to 20s Uncontrolled process steps eliminated Critical controlled process steps Powder application - operator Cure process Powder application - spray gun Loading Unloading IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Control Plan Worksheet Critical to Quality (CTQs) factors listed according to RPN ranking Process step as listed in process map Inputs/outputs Process specifications Measurement system Current control plan Control method Who Where When Reaction plan IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Control Plan Follow-up Revision of current standard operating procedures (SOP) Establishment of standard operating procedures for CTQs that do not already have an SOP Periodic review IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Presenter: Dr. Joan Burtner, Mercer University Future Work Phase 1 Development of plan for constant metrics Implementation of new SOPs Phase 2 Periodic process review Implementation of new metrics as needed Phase 3 Project closure Implementation of related Six Sigma projects IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University

Presenter: Dr. Joan Burtner, Mercer University Contact Information Burtner_J@Mercer.edu Room 105D, School of Engineering Phone (478) 301- 4127 Fax (478) 301- 2331 IIE Annual Conference May 2004 Presenter: Dr. Joan Burtner, Mercer University