ISO INTERNATIONAL STANDARD 7870-8 First edition 2017-04 Control charts - Part 8: Charting techniques for short runs and small mixed batches Cartes de controle - Partie 8: Techniques de cartes pour petites séries et pour petits lots combines Reference number ISO 7870-8:2017(E) so International Organization for Standardization @ IS0 2017 e=ZHEJIANG INST OF STANDARDIZATION C1 5956617 vided by IHS under I No reproduction or networking permitted without license from IHS IS0 7870-8:2017(E) COPYRIGHTPROTECTEDDOCUMENT IS0 2017, Published in Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISO's member body in the country of the requester. ISOcopyrightoffice Ch. de Blandonnet 8 . CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyright@iso.org www.iso.org Internationai ibrg DrganizationforStandardization Licensee-ZHEJIANG INST.OF STANDARDIZzRoISQ7 - All rights reserved Not for Resale, 2017/5/16 00:40:49 networking permited withoutlicense from IHS IS0 7870-8:2017(E) Contents Page Foreword ..V Introduction. ..vi 1 Scope. ..1 2 Normative references ..1 3 Terms, definitions and symbols 3.1 Terms and definitions 3.2 Symbols... 1 4 How to select the correct type of Shewhart control chart for continuous variables data....2 4.1 General. 4.2 How to select the correct type of Shewhart control chart for measured data generally....2 4.3 How to select the Shewhart control chart when the characteristic does not have a constantaimorprocessspread .3 5 How to prepare for short run, small mixed batch control charting ..5 5.1 Focus on the process 5 5.2 Procedure for grouping similarprocesses .5 5.3 Typical applications.. .7 5.4 Preliminary process diagnosis. .8 5.5 Procedure to establish the correct initial set-up of a process characteristic .8 5.5.1 Purpose. .8 5.5.2 Scope and limitations. ..8 5.5.3 Reasons for need of procedure. ..8 5.5.4 Method. 5.5.5 Example .10 5.6 Procedure to pre-establish control limits for SPC charts for short run, small batch, processes ..11 5.6.1 Purpose ..11 5.6.2 Scope of application .11 5.6.3 Reasons for need of procedure .11 5.6.4 Method. .11 5.6.5 Example ..12 6 How to establish and apply short run, small mixed batch, control charts ..15 6.1 General 15 6.2 Variable aim, individual and moving range chart .15 6.2.1 Purpose ..15 6.2.2 Scope of application. .16 6.2.3 Method. 16 6.2.4 Example .16 6.3 Variable aim, moving mean and moving range chart ..18 6.3.1 Purpose ..18 6.3.2 Scope of application. .18 6.3.3 Method. ..18 6.3.4 Example 19 6.4 Universal, individual and moving range chart 20 6.4.1 Purpose 20 6.4.2 Scope of application. 20 6.4.3 Method. 20 6.4.4 Example 21 6.5 Universal, moving mean and moving range chart 22 6.5.1 Purpose 22 6.5.2 Scope of application. 23 6.5.3 Method .23 6.5.4 Example 24 ii icensee=ZHEJIANG INST OF STANDARDIZATION C1 5956617 ed without license from IHS Not for Resale, 2017/5/16 00:40:49