MSA测量系统分析(英文版).ppt

SPC for Test System § Gauge RR Basic Concepts Every Process produce a “ Product”. Every product possesses Qualities ( Features) Every Quality Feature Can be measured Total Variation = Product Variation + Measurement Variation Some Variation Inherent in System Design. Some Variation is due to a Faulty performance of the System(s). Components of Measurement System Equipment or Gage Type of Gage: Attribute: go-no go, vision systems Variable: calipers, probe, coordinate measurement machines Unit of Measurement - discrimination At least 1/10 of 6*process standard deviation (6s) Other rules: at least 1/10 of tolerance Operator Operating Instructions Part locating or orientation scheme a gage must be able to consistently locate the part being measured. Terms You Should Know Terms You Should Know 1. Accuracy 2. Reproducibility 3. Repeatability (Precision) 4. Stability Precision and Accuracy Accuracy and Stability Measurement System Variables Possible Sources of ProcessVariation Sources of Measurement Error Systematic Variations 1. accuracy: improper calibration of equipment 2. reproducibility: different operators using same equipment with different techniques Random Variations 3. repeatability: (for example, inconsistent part locating) Periodic Variations 4. stability: wear, deterioration, environmental conditions The GRR Design Model The Components of Variance Measurement Error – Gage RR Averages Types of Gage Error and AnalysisMethods: Variance Partitioning Two Way Anova Table Gage RR Acceptance Criteria for Evaluating Gage RR Conducting a Gage RR Study Conducting a Gage RR Study Guidelines For Gauge RR Acceptance Gauge RR Study Gauge RR Study Gauge RR Study Gauge RR Study Gauge RR Study Anova Method Example Equipment Calibration By Simple Linearity Model ( Y = mX + b ) Selection of Standard Units Regression Analysis : Equipment vs Standard Measurement Data of Standard Sets @ each Test Machine Regression Analysis Add Translation Key Equipment Long Term Stabi