_STP_15C-1962.pdf

ASTM MANUAL 0 QUALITY CONTROL OF MATERIALS Reg.U.S.Pat.OiL Prepared by ASTM COMMITTEE E-11 On Quality Control of Materials Part 1-Presentation of Data Part 2rePresenting Limits of Uncertainty of an Observed Average Part S-Control Chart Method of Analysis and Presentation of Data Special ffechnical Publication 15-C January,I95I Price:$2.50;to Members,$2.00 Published by the AMERICAN SOCIETY FOR TESTING MATERIALS x916 Race St.,Philadelphia 3,Pa.Copyright by ASTM Intl(all rights reserved);Fri Dec 11 20:03:48 EST 2015Downloaded/printed byUniversity of Washington(University of Washington)pursuant to License Agreement.No further reproductions authorized.NOTE-The Society is not responsible,as a body,for the statements and opinions advanced in this publication.Copyrighted,1951 by the AMERICAN SOCIETY:FOR TESTING MATERIAL8 Printed in Baltimore,U.S.A.First Printing,March,1951 Second Printing,May,1951 Third Printing August,1952 Fourth Printing,September,1954 Fifth Printing,September,1956 Sixth Printing,December,1957 Seventh Printing,July,1960 Eighth Printing,December,1962 Copyright by ASTM Intl(all rights reserved);Fri Dec 11 20:03:48 EST 2015Downloaded/printed byUniversity of Washington(University of Washington)pursuant to License Agreement.No further reproductions authorized.PREFACE This Manual on the Quality Control of Materials was prepared by ASTM Technical Committee E-1I on Quality Control of Materials to make available to the ASTM membership,and others,information re-garding statistical methods and quality control methods and to make recommendations for their application in engineering work of the Society.The quality control methods considered herein are those methods that have been developed on a statistical basis to control the quality of product through the proper relation of specification,productio n,and inspection as parts of a continuing process.This Manual consists of three Parts dealing particularly with the analysis and presentation of data.It constitutes a revision and a replacement of the ASTM Manual on Presentation of Data whose main section and two sup-plements were first published respectively in 1933 and 1935.This early work was done with the ready cooperation of the Joint Committee on the Develop-ment of Applications of Statistics in Engineering and Manufacturing(spon-sored by the American Society for Testing Materials and the American Society of Mechanical Engineers)and especially of the Chairman of the Joint Committee,W.A.Shewhart.Over the past 15 years this material has gone through a number of minor modifications and reprintings and has be-come a standard of reference over wide areas in both industrial and academic fields.Its nomenclature and symbolism were adopted in 1941 and 1942 in the American War Standards on Quality Control(Zl.1,Z1.2 and Z1.3)of the American Standards Association,and its Supplement B was reproduced as an appendix with one of these Standards.The purposes for which the Society was founded-the promotion of knowledge of the materials of engineering,and the standardization of speci-fications and the methods of testing-involve at every turn the collection,analysis,interpretation and presentation of quantitative data.Such data form an important part of the source material used in arriving at new knowledge,and in selecting standards of quality and methods of testing that are adequate,satisfactory,and economic,from the standpoints of the producer and the consumer.Broadly,the three general objects of gathering engineering data are to discover:(1)physical constants and frequency distributions,(2)relation-ships-both functional and statistical-between two or more variables,and(3)causes of observed phenomena.Under these general headings,the follow-ing more specific objectives in the work of the American Society for Testing Materials may be cited:iii Copyright by ASTM Intl(all rights reserved);Fri Dec 11 20:03:48 EST 2015Downloaded/printed byUniversity of Washington(University of Washington)pursuant to License Agreement.No further reproductions authorized.iv PRXFAC(a)to discover the distributions of quality characteristics of materials which serve as a basis for setting economic standards of quality,for com-paring the relative merits of two or more materials for a particular use,for controlling quality at desired levels,for predicting what variations in quality may be expected in subsequently produced material;to discover the distributions of the errors of measurement for particular test methods,which serve as a basis for comparing the relative merits of two or more methods of testing,for specifying the precision and accuracy of standard tests,for setting up economical testing and sampling procedures;(b)to discover the relationship between two or more properties of a material,such as density and tensile strength;and(c)to discover physical causes of the behavior of materials under partic-ular service conditions;to discover the causes of nonconformance with specified standards in order