Quality Management in the Bosch Group | Technical Statistics 10. Capability of Measurement and Test Processes Page intentionally left blank Booklet 10 ― Capability of Measurement and Test Processes Quality Management in the Bosch Group Technical Statistics Booklet 10 Capability of Measurement and Test Processes Edition November 2019 2019 Robert Bosch GmbH | 11.2019 Booklet 10 ― Capability of Measurement and Test Processes Edition November 2019 The minimum requirements for capability criteria given in this booklet correspond to the requirements at the time of publishing the present edition. For the determination of current minimum requirements for capability criteria the CDQ 0301 is binding. 2019 Robert Bosch GmbH | 11.2019 Booklet 10 ― Capability of Measurement and Test Processes Contents 1 Introduction .......................................................................................................................................................... 1 2 Scope ................................................................................................................................................................... 1 3 Flow Charts .......................................................................................................................................................... 3 4 Procedures for Verification of Measurement Process Capability by Means of Continuous Characteristics .... 8 4.1 Procedure 1 (type-1 study): Systematic measurement error and repeatability ........................................ 8 4.2 Procedure 2 (type-2 study): Repeatability and reproducibility (gage R&R) with operator influence ........ 12 4.3 Procedure 3 (type-3 study): Repeatability and reproducibility (gage R&R) without operator influence... 15 4.4 Procedure 4: Linearity ................................................................................................................................. 18 4.5 Procedure 5: Stability .................................................................................................................................. 19 4.5.1 Preparing stability monitoring ............................................................................................................ 19 4.5.2 Sampling interval ............................................................................................................................... 21 4.5.3 Conducting stability monitoring ......................................................................................................... 21 4.6 Repetition of capability studies ................................................................................................................... 22 5 Procedures for Verification of Test Process Capability by Means of Discrete Characteristics .................... 24 5.1 Procedure 6: Test decisions for discretized continuous characteristics .................................................. 24 5.2 Procedure 7: Test decisions for discrete and discretized continuous characteristics ............................ 28 5.3 Notes on stability monitoring and repetition of capability studies ............................................................ 32 6 Assessment of Non-Capable Measurement and Test Processes ................................................................. 32 Appendix .................................................................................................................................................................... 33 A Examples of Checklists for Measurement Process Analyses ........................................................................ 33 B Forms for Manual Analysis ............................................................................................................................... 35 C Amendments and Notes on Procedure 1 ........................................................................................................ 43 C.1 Significance of systematic measurement errors ....................................................................................... 43 C.2 Determination of the significance criterion for systematic measurement errors ..................................... 43 C.3 Characteristics with a one-sided limit and without a natural limit ............................................................. 44 D Amendments and Notes on Procedures 2 and 3 ............................................................................................ 46 D.1 Parameter ndc ............................................................................................................................................. 46 D.2 Procedure 2: Analysis using “analysis of variances (ANOVA)” ............................................................... 48 D.3 Analysis using the “average range method (ARM)” ................................................................................. 52 D.4 K-factors for ARM ........................................................................................................................................ 53 D.5 Approach in case of an insufficient number of measuring objects .......................................................... 55 D.6 Procedure 1 – procedure 2 and 3: Inconsistent classification into capability categories ....................... 56 E Amendments and Notes on Procedure 4 (Linearity) ...................................................................................... 58 E.1 Procedure according to AIAG MSA ........................................................................................................... 58 E.2 Multiple use of procedure 1: Additional considerations ............................................................................ 63 F Procedure 5: Factors for the Calculation of Control Limits ............................................................................. 64 G Parameter “Kappa” () ...................................................................................................................................... 65 G.1 Mathematical background .......................................................................................................................... 65 G.2 Manual analysis using data from AIAG MSA as an example .................................................................. 67 G.3 Analysis using commercial statistics software: Minitab ............................................................................ 71 G.4 Single stage and multiple stage test processes: Attribute gage as an example .................................... 74 Table of symbols ....................................................................................................................................................... 75 Definition of terms ...................................................................................................................................................... 79 Literature .................................................................................................................................................................... 86 Index ........................................................................................................................................................................... 87 2019 Robert Bosch GmbH | 11.2019 – i – Booklet 10 ― Capability of Measurement and Test Processes List of flow charts Fig. 1: Capability study – overview of stages and responsibilities ...................................................................... 3 Fig. 2: Superordinate work flow of capability studies for measurement and test processes (level 1) ............... 4 Fig. 3: Level-2 work flow of a capability study of measurement processes for continuous characteristics ...... 5 Fig. 4: Level-3 work flow of a capability study of measurement processes for continuous characteristics ...... 6 Fig. 5: Level-2 work flow of a capability study of test processes for discrete characteristics ............................ 7 Fig. 6: Level-4 work flow of a capability study according to procedure 1 (type-1 study) ................................. 10 Fig. 7: Level-4 work flow of a capability study according to procedure 2 (type-2 study) ................................. 13 Fig. 8: Level-4 work flow of a capability study according to procedure 3 (type-3 study) ................................. 16 Fig. 9: Stability monitoring for continuous characteristics (procedure 5) .......................................................... 19 2019 Robert Bosch GmbH | 11.2019 – ii – Booklet 10 ― Capability of Measurement and Test Processes 1 Introduction The procedures described in the present booklet are part of the Bosch quality management. They are incorporated by means of the management manual [MM] and the central directive [CDQ 0301]. The present issue of Booklet 10 complies with the requirements according to [AIAG MSA]. Procedure 2 directly conforms to [AIAG MSA]. In the present booklet, standardized terminology is preferably used which also ensures unambiguousness in a legal case due to its definition and international acceptance (see chapter “Definition of terms”). NOTE: The definitions of various standardized terms only differ marginally in currently applicable standards, i.e. the terms are used synonymously in practice. In these cases, terms are used in this document which are commonly used in the respective context (example: measuring system, measuring equipment, measuring instrument). Verification of capability and monitoring of stability of measurement processes are