Taguchi MethodTaguchi MethodPresented by:Presented by:

Bobby WyrwaBobby Wyrwa

IE672-852

Professor Bernier

4/25/12

Dr. Genichi Taguchi

Electrical Communication Electrical Communication Laboratories Laboratories

Murry Hill, New Jersey Tokyo, Japan

Dr. Taguchi – Head of R&D Productivity and Product Quality

ConceptsConcepts

Quality should be designed into the product and Quality should be designed into the product and not inspected into it not inspected into it

Quality is best achieved by minimizing the Quality is best achieved by minimizing the deviation from the target deviation from the target

The cost of quality should be measured as a The cost of quality should be measured as a function of deviation from the standard and the function of deviation from the standard and the losses should be measured system-wide losses should be measured system-wide

Quality Designed Into the ProductQuality Designed Into the Product

Quality improvement begins at the design Quality improvement begins at the design stagestage

Continues through to the production stageContinues through to the production stage

Inspection, screening, or salvaging does Inspection, screening, or salvaging does not improve poor qualitynot improve poor quality

Quality should be based on the philosophy Quality should be based on the philosophy of prevention.of prevention.

Minimizing Deviation From the Minimizing Deviation From the TargetTarget

Quality is directly related to the deviation of a Quality is directly related to the deviation of a design parameter from the target value design parameter from the target value

Properties skewed toward one end of an Properties skewed toward one end of an acceptance range yet show a shorter life acceptance range yet show a shorter life expectancyexpectancy

– Step 1: Specify a target valueStep 1: Specify a target value– Step 2: Develop manufacturing process to meet target Step 2: Develop manufacturing process to meet target

valuevalue

Quality As a Function of DeviationQuality As a Function of Deviation

Measuring deviations from a given design Measuring deviations from a given design parameter in terms of the overall life cycle parameter in terms of the overall life cycle costs of the productcosts of the product

Scrap, rework, inspections, returns, or Scrap, rework, inspections, returns, or product replacement product replacement

Limitations of Quality ControlLimitations of Quality Control

The need for timing with respect to The need for timing with respect to product/process developmentproduct/process development

Techniques MUST be applied in the early Techniques MUST be applied in the early stages of the designstages of the design

Taguchi method may not always apply Taguchi method may not always apply

Design Parameters for Reduced Design Parameters for Reduced VariationVariation

Reducing the variation around the targetReducing the variation around the target– Easier to attain qualityEasier to attain quality

Highly used for industrial settingsHighly used for industrial settings

Low cost solutions can be found by Low cost solutions can be found by adjusting the levels and controlling the adjusting the levels and controlling the variation of OTHER factorsvariation of OTHER factors

Cost savings exceed the cost of additional Cost savings exceed the cost of additional experiments experiments

ExampleExampleProcess objectiveProcess objective: Economic : Economic

manufacturing of high quality (color, manufacturing of high quality (color, size, …) tilessize, …) tiles

ProblemProblem: Uneven size due to : Uneven size due to temperature variation in kilntemperature variation in kiln

Traditional approachTraditional approach: Redesign kiln for : Redesign kiln for more even temperature distribution more even temperature distribution ($.5M investment with no guarantee)($.5M investment with no guarantee)

Robust design approachRobust design approach: Find a set : Find a set product or process design parameters product or process design parameters that makes the size insensitive to that makes the size insensitive to temperature variationtemperature variation

SolutionSolution: Increase lime content from : Increase lime content from 1% to 5% in clay1% to 5% in clay

Thank YouThank You

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