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Process Control -A Preventive Approach for Total Control During Production

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Process Control -A Preventive Approach for Total Control During Production The MPCpS ® Methodology Process Control -A Preventive Approach For Total Control During Production - Mario Perez-Wilson v "The MPCpS Methodology - Process Control" For books, software, public seminars, in-house training seminars, and consulting services please contact: Advanced Systems Consultants Post Office Box 5257 Scottsdale, Arizona 85261 U.S.A. Phone (480) 423-0081 www.mpcps.com THE MPCpS METHODOLOGY - PROCESS CONTROL First Published 2014 Copyright © 2014, Mario Perez-Wilson. All Rights Reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without permission in writing from Advanced Systems Consultants. Current Printing (last digit) 10 9 8 7 6 5 4 3 2 1 PRINTED IN THE UNITED STATES OF AMERICA ISBN 978-1-883237-52-3 iv TCM Table of Contents 1. Functional Equilibrium Introduction . 1-1 The MPCpS Methodology . 1-9 2. Variation and Statistical Control Measures of Central Tendency . 2-2 Measures of Spread . 2-3 Histograms . 2-6 Populations & Samples . 2-7 The Normal Distribution . 2-8 Central Limit Theorem . 2-12 Variation . 2-17 State of Statistical Control . 2-20 Control Limits & Factors . 2-22 Range (R) Chart . 2-27 Test for Detecting Unnaturalness . 2-29 Procedure of Test for Unnaturalness . 2-30 Tests for the Range Chart . 2-38 Tests for Detecting Unnatural Patterns . 2-44 3. Run Charts and Control Charts Introduction . 3-1 Chart Type Selection Flowchart . 3-2 Run Charts . 3-3 X&R Charts . 3-7 Moving Range (MR) Charts . 3-27 p Charts . 3-41 np Charts . 3-53 c Charts . 3-57 u Charts . 3-67 Corrective Action Log (CAL) . 3-71 Out-of-Control Action Plan (OCAP) . 3-79 4. Tolerancing Tolerance . 4-2 MPCpS - Control Advanced Systems Consultants © 2014, Mario Perez-Wilson ix P.O. Box 5257, Scottsdale, AZ 85261, Tel: (480) 423-0081 TCM Table of Contents (continued) Statistical Tolerance Limits . 4-4 Alternative Methods for Statistical Tolerance Limits . 4-13 Tolerance Stacking . 4-18 Scatter Diagrams . 4-26 Simple Linear Regression . 4-33 The Method of Least Squares . 4-40 Degree of Association Between X and Y . 4-46 Computation Formula for the Coefficient of Determination . 4-49 Correlation Coefficient . 4-51 ProSolution Matrix . 4-52 5. Positive Control Positrol Description . 5-2 Positrol Plan . 5-3 Construction of Positrol Plans . 5-16 Transfer of Knowledge . 5-39 Examples of Positrol Plans . 5-47 Positrol Logs Description . 5-59 Construction of Positrol Logs . 5-61 Examples of Positrol Logs . 5-67 Work Standards (WS) . 5-73 Components of a Work Standard . 5-77 Examples of Work Standards . 5-80 Preventive Maintenance (PM) . 5-85 6. Multi-Variable and Cumulative Charts Cumulative Count Charts . 6-2 Tests for Lack of Statistical Control . 6-5 Construction of a Cumulative Count Chart . 6-6 Simulating a Progression of Cumulative Count Chart . 6-11 Multi-Vari Charts . 6-19 Construction of Multi-Vari Charts . 6-21 Statistical Analysis of Multi-Vari Charts . 6-27 Estimating Positional Variation . 6-28 Estimating Cyclical Vatiation . 6-30 MPCpS - Control Advanced Systems Consultants © 2014, Mario Perez-Wilson x P.O. Box 5257, Scottsdale, AZ 85261, Tel: (480) 423-0081 TCM Table of Contents (continued) Estimating Temporal Variation . 6-32 Analysis of Variance of Multi-Vari Charts . 6-35 Notes on CLT . 6-52 Case Studies & Examples . 6-55 7. Appendix . 7-1 Tables . 7-2 Forms . 7-20 8. References and Bibliography . 8-1 Author . 8-5 Comments From Our Customers . 8-7 MPCpS - Control Advanced Systems Consultants © 2014, Mario Perez-Wilson xi P.O. Box 5257, Scottsdale, AZ 85261, Tel: (480) 423-0081 TCMAAAAAA TCMAA Section 1 - Functional Equilibrium Introduction Production machines are usually purchased to perform a particular transformation of raw materials into finished or semi-finished products. A production system is comprised of machines, gauges, raw materials, sub- assemblies, components, labor, methods and activities. All support producing a quality product at a minimum cost for on-time delivery to the customer. The methods and activities involved in the support of the production system are: the preparation of raw materials or sometimes parts pieced into kits; the selection of tools to be used; the mounting and demounting of fixtures, frames, plates, boats or cassettes; the adjustments to equipment; the use of gauges and inspection of parts; the actual processing of the machines and/or tools; the maintenance of all equipment; the understanding and conformance with production instructions, and the recovery in the event that something goes wrong. And all of these activities must be done without errors while maintaining a good degree of safety. Production System Machines Gauges Labor Materials Quality Methods Quality Procedures Logistics Cost Raw MaterialsTools Finished Product Cost Fixtures Activities On time Behavior On-time delivery Ergonomics delivery Discipline Human Factors Technology Maintenance Inspection Even in the production of the most simple of products, the production system is complex and its uneventful functioning requires a lot of attention to detail. When the products are complex or difficult to produce, the production system will usually carry a quite higher degree of complexity. MPCpS - Control Advanced Systems Consultants © 2014, Mario Perez-Wilson 1-1 P.O. Box 5257, Scottsdale, AZ 85261, Tel: (480) 423-0081 TCMAAAAAA TCMAA The state of functional equilibrium is not a natural state such as a state of statistical control where the responses are only affected by chance. In a state of functional equilibrium, we force the functional state of the system to operate as it was designed, to purposely extend the optimal functionality throughout the life of the product. This is done by means of a controlled feedback-loop operational methodology called the Total Control Methodology, TCM. The Total Control Methodology attempts to establish a system of rigorous control of the production system by a very precise procedural methodology. Its objectives are to preserve an understood process perpetually in a state of functional equilibrium. This means having all elements of the production system working in synergy, maintaining stability, capability and remaining fool-proof of defects as established during its characterization and optimization stages. Independent Variables UCLAAAAAA LCL AAAAAA Total Control Methodology Cause & Effect Relationship LSL Responses USL TCM establishes monitors, checks and control requirements for the production system and does this specifically, but not limited to responses, variables, materials, resources, maintenance and setup. TCM equally checks that known preestablished cause-and- effect relationships have not been superseded by unknown ones. MPCpS - Control Advanced Systems Consultants © 2014, Mario Perez-Wilson 1-6 P.O. Box 5257, Scottsdale, AZ 85261, Tel: (480) 423-0081 TCMAAAAAA TCMAA Manpower Machine Traceability Poor Too much variability Operator Discipline Changes Made by Non available Operation Engineering Not correct To build quality Accountability Procedures - Avoid spec No procedure Poor efficiency Not followed No standardization Equipment Not respected Don't know how Not tracking quality Too many breakdowns to fix process Needs oper. assistance Too technical Vendors changed Difficult to follow Trivial Many Assembly Intr. Process Materials & Vital Few Not consistent in Variables Production Intr. Resources running process Changing Not motivated No Traceability Inspection Intr. Not trained New Dominating Variables Operation No in-coming Operator inspection Too time consuming Not listened Training No Procedure No history Not asked Equip. Setup Not available Not Done Constantly changing the Process Qual. Not Consistent process Maintenance Too infrequent No Qualification Don't experiment No schedule Process Not Engr'g No education on No procedure under control Don't understand process product, customer.
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