1、 AEROSPACE RECOMMENDED PRACTICE Statistical Product Acceptance Requirements SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitabili
2、ty for any particular use, including any patent infringement arising therefrom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyright
3、 2005 SAE International All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER:
4、 Tel: 877-606-7323 (inside USA and Canada) Tel: 724-776-4970 (outside USA) Fax: 724-776-0790 Email: custsvcsae.org SAE WEB ADDRESS: http:/www.sae.org Issued 2005-10 ARP9013 FOREWORD To assure customer satisfaction, aerospace industry organizations shall produce, and continually improve, safe, reliab
5、le products that meet or exceed customer and regulatory authority requirements. The globalization of the aerospace industry, and the resulting diversity of regional/national requirements and expectations, has complicated this objective. End-product organizations face the challenge of assuring the qu
6、ality of, and integrating, product purchased from suppliers throughout the world and at all levels within the supply chain. Aerospace suppliers and processors face the challenge of delivering product to multiple customers having varying quality expectations and requirements. The aerospace industry e
7、stablished the International Aerospace Quality Group (IAQG) for the purpose of achieving significant improvements in quality and safety, and reductions in cost, throughout the value stream. This organization includes representation from aerospace companies in the Americas, Asia/Pacific, and Europe.
8、This recommended practice has been prepared by the Americas Aerospace Quality Group (AAQG). This document standardizes, to the greatest extent possible, the requirements on statistical techniques for product acceptance in the aerospace industry. The establishment of common requirements, for use at a
9、ll levels of the supply-chain, by organizations around the world, should result in improved quality and safety, and decreased costs due to the elimination or reduction of organization-unique requirements and the resultant variation inherent in these multiple expectations. SAE ARP9013 - 2 - INTRODUCT
10、ION This recommended practices series of documents establishes the general requirements applicable to any of the methods of statistical product acceptance to reduce inspection costs while still assuring acceptable quality. There is no single specific plan that can be considered best suited for all a
11、pplications or processes. This ARP9013 document contains the basic requirements needed to implement the statistical methods described in ARP9013/1 through ARP9013/4 series to control outgoing quality. All applicable requirements of this ARP9013 document shall be met when using one or more of the ARP
12、9013/1 through ARP9013/4 recommended practices. This document does not apply to statistical methods that are separate from product acceptance. Many companies use excellent statistical methods solely to monitor and improve their product quality, and those methods are not subject to the requirements o
13、f this document. This document applies only to those statistical methods used for product acceptance. The requirements are contained in the main body of this recommended practice. This recommended practice also includes several appendices, which are offered for guidance or recommendation purposes on
14、ly. Each appendix herein contains only nonmandatory suggestions, examples, or further discussion on specific topics that the authorship believes will aid the successful implementation of this recommended practice for the user organization. Products which may be eligible for the methods defined in th
15、is recommended practices series include but are not limited to end items; cast, forged, wrought, machined, fabricated, plastic, molded, powdered metal, or stamped components and raw material; electronic, electrical, and mechanical components; lots subjected to receiving inspection, in-process inspec
16、tion, and final inspection; supplies in storage; and services, any of which may be produced in batches, large or small lots, continuous processes, or single-piece flow manufacturing processes. SAE ARP9013 - 3 - TABLE OF CONTENTS FOREWORD.1 INTRODUCTION 2 1. SCOPE 4 1.1 Purpose4 1.2 Field of Applicat
17、ion.4 2. REFERENCES.4 2.1 Applicable Documents .4 2.2 Related Publications 6 2.3 Definitions 7 3. GENERAL REQUIREMENTS 16 3.1 Trained Personnel16 3.2 Safety/Critical Characteristics 16 3.3 Quality Parameters 17 3.4 Drawing Samples.17 3.5 Identification of Design Characteristics17 3.6 Measurement Sys
18、tems 18 3.7 Nonconformances in the Sample.18 3.8 Statistical Product Acceptance Plans and Records .18 3.9 Alternate Statistical Techniques for Product Acceptance 18 3.10 Auditing of Statistical Techniques for Product Acceptance18 4. REQUIRED CONTENT FOR DOCUMENTED PROCEDURES 19 4.1 Assigning Quality
19、 Parameters and Statistical Techniques for Product Acceptance 19 4.2 Assigning Responsibilities19 4.3 Assigning Where Applied.19 4.4 Establishing a Training Program20 4.5 Controlling Nonconformances20 4.6 Monitoring Performance and Effectiveness .20 4.7 Defining Adjustments to Inspection Frequency20
20、 4.8 Customer Approval of Procedures and Plans 20 APPENDIX A GUIDELINES AND RECOMMENDATIONS FOR SUCCESSFUL IMPLEMENTATION21 APPENDIX B GUIDELINES FOR 4.1 ASSIGNING QUALITY PARAMETERS AND STATISTICAL TECHNIQUES FOR PRODUCT ACCEPTANCE .29 APPENDIX C DISCUSSION ON THE RELATIONSHIP OF QUALITY PARAMETERS
21、 TO RELIABILITY 32 SAE ARP9013 - 4 - 1. SCOPE: 1.1 Purpose: This SAE Aerospace Recommended Practice (ARP) establishes the general requirements when implementing any of the statistical product acceptance methods as defined in ARP9013/1, ARP9013/2, ARP9013/3, and ARP9013/4. This recommended practice a
22、lso establishes the minimum content required to be covered in an organizations documented procedures that govern their application of statistical product acceptance methods. These general requirements and documented procedures apply the requirements of AS9100 plus requirements for retrievability, sa
23、fety/critical characteristics, quality parameters, and that these parameters protect the customer. This recommended practice is to be used in conjunction with the variety of sampling strategies, statistical techniques, and process control methods of the ARP9013/1 through ARP9013/4 recommended practi
24、ces as chosen by the organization. 1.2 Field of Application: This recommended practice is applicable when invoked in a purchasing contract or specification, other contractual document, customer agreement, or adopted by the organization. The appropriate slash-numbered recommended practice(s) in this
25、series applied by the organization may or may not be specified by the purchasers contract, but does form a part of the ARP9013 flowdown requirement. If desired to sample a series of lots without using ARP9013/1, ARP9013/2, or ARP9013/3, the requirements of ARP9013/4 shall be used. 2. REFERENCES: 2.1
26、 Applicable Documents: The following publications form a part of this document to the extent specified herein. The latest issue of SAE publications shall apply. The applicable issue of other publications shall be the issue in effect on the date of the purchase order. Nothing in this document, howeve
27、r, supersedes applicable laws, regulations, and contractual requirements. SAE ARP9013 - 5 - 2.1.1 SAE Publications: Available from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org. ARP9013/1 Statistical Produ
28、ct Acceptance Requirements Using Isolated Lot Sampling Methods ARP9013/2 Statistical Product Acceptance Requirements Using Attribute or Variable Lot Acceptance Sampling Plans ARP9013/3 Statistical Product Acceptance Requirements Using Process Control Methods ARP9013/4 Statistical Product Acceptance
29、Requirements Using Continuous Sampling, Skip-Lot Sampling, or Methods for Special Cases AS9100 Quality Management Systems - Aerospace - Requirements AS9103 Variation Management of Key Characteristics 2.1.2 ANSI/ASQC Publications: Available from the American Society for Quality (ASQ), 600 North Plank
30、inton Avenue, Milwaukee, WI 53203, Tel: 800-248-1946 or 414-272-8575, www.asq.org ANSI/ASQC B1 Guide for Quality Control Charts ANSI/ASQC B2 Control Chart Method of Analyzing Data ANSI/ASQC B3 Control Chart Method of Controlling Quality During Production ANSI/ASQC Q3 Sampling Procedures and Tables f
31、or Inspection of Isolated Lots by Attributes ANSI/ASQC S1 An Attribute Skip-Lot Sampling Program ANSI/ASQC Z1.4 Sampling Procedures and Tables for Inspection by Attributes ANSI/ASQC Z1.9 Sampling Procedures and Tables for Inspection by Variables for Percent Nonconforming SAE ARP9013 - 6 - 2.1.3 Appl
32、icable References: Available from the Document Automation and Production Service (DAPS), Building 4/D, 700 Robbins Avenue, Philadelphia, PA 19111-5094, Tel: 215-697-6257, http:/assist.daps.dla.mil/quicksearch/. MIL-STD-1235 Single and Multi-Level Continuous Sampling Procedures and Table for Inspecti
33、on by Attributes NOTE: MIL-STD-1235 has been cancelled but may be used as a guide for derivation and application of continuous sampling plans. Appendix A of ARP9013/4 contains the essential text and tables of MIL-STD-1235C with some editing, reformatting, and paragraph renumbering; however, all the
34、functional curves have been purposely omitted to conserve the length of the recommended practice. 2.2 Related Publications: ISO 2859/2 “Sampling Plans Indexed by Limiting Quality (LQ) for Isolated Lot Inspection,” may be obtained from any ISO Licensors members or from the ISO Secretariat, Case Posta
35、le 56, 1211 Geneva 20, Switzerland. N. L. Squeglia, “Zero Acceptance Number Sampling Plans,“ ASQ Quality Press, 611 East Wisconsin Avenue, P.O. Box 3005, Milwaukee, WI 53201-3005. Braverman, Jerome D., “Fundamentals of Statistical Quality Control,” New Jersey: Prentice Hall, 1981. Grant, Eugene L. a
36、nd Leavenworth, Richard S., “Statistical Quality Control,” New York: McGraw Hill Company, 1996. Dodge, H. F., “Chain Sampling Inspection Plan,” Industrial Quality Control, 11, No. 4 (January 1955), 10-13. Besterfield, Dale H., “Quality Control”, Additional Acceptance Sampling Plan Systems, 7, Third
37、Edition, 1990, 272-275. Scheaffer, R. L. and McClave, J. T., “Probability and Statistics for Engineers,” 2nd Edition, PWS Publishers, Duxbury Press, 1986, 280-281. SAE ARP9013 - 7 - 2.3 Definitions: ACCEPTABLE QUALITY LEVEL (AQL): The maximum percentage or proportion of nonconforming units in a lot
38、or batch that, for purposes of acceptance sampling, would be considered satisfactory as a process average. See 3.3 and Appendix A. ACCEPTANCE SAMPLING: Inspection in which decisions are made to accept or not accept a lot (or other grouping of product or material) based on the results of a sample or
39、samples selected from that lot or grouping. ANALYSIS OF VARIANCE (ANOVA): An arithmetic process developed for the purpose of comparing several sample means by partitioning the total variation of a set of data into components associated with recognized sources of variation. ATTRIBUTE DATA: Qualitativ
40、e data that counts the presence or absence of a characteristic evaluated to a specified criterion, rather than data from a discrete measurement on a continuous scale. Attribute data is typically measured on a go/no-go, pass/fail, or yes/no basis. AVERAGE OUTGOING QUALITY (AOQ): The average quality o
41、f outgoing product after sampling inspection for a given steady value of incoming product quality. Achieving reasonable values of the AOQ usually requires that units found nonconforming are replaced with units known to be conforming. Both incoming and outgoing quality are generally expressed in term
42、s of the percent of nonconforming product. AVERAGE OUTGOING QUALITY LIMIT (AOQL): Maximum AOQ over all possible values of incoming product quality level for a given acceptance sampling plan. AVERAGE RUN LENGTH (ARL): The average number of plotted points on a control chart or the average number of it
43、ems inspected before a shift in process level may be expected to be signaled. A typical benchmark is the average number of samples before a 2-sigma shift in the process produces a signal. A measure of effectiveness of detecting sustained shifts. SAE ARP9013 - 8 - 2.3 (Continued): BERNOULLI TRIALS MO
44、DEL: A model where (1) the same kind of trial is repeated several times; (2) on each trial there are two possible outcomes, for example, conforming or nonconforming; (3) repeated trials (units of product) are independent; and (4) the probability of each outcome remains the same for each trial. In a
45、Bernoulli trials model, the probability of exactly k nonconforming units in n trials is given by: () ()knkp1pknp;k,nb= (Eq. 1) where: b(n, k; p) is the probability of k nonconforming items in n trials n is the fixed number of Bernoulli trials k is the number of nonconforming units in n trials p is t
46、he probability of a nonconforming unit and (1-p) is the probability of a conforming unit. This is called a binomial probability. BINOMIAL DISTRIBUTION: In the literature of statistics, the binomial as a probability distribution results from a Bernoulli trials model of the process. C=0: An acceptance
47、-sampling plan that requires rejection of the lot if the sample contains one or more nonconformances. CAPABILITY: The range of six standard deviations of the values in a process having no changes in its mean or any other characteristic of its distribution. The inherent variation in a stable process.
48、 For the case of attribute data, it is usually defined as the average proportion or rate of defects or defectives (e.g., centerline of an attribute control chart). The Bayesian estimator for defect rate when no defects are observed in the current sample is: )2n(1)d(P+= (Eq. 2) where: P (d) is the pr
49、obability of a defect (the defect rate) n is the number of representative observations of the process, no defects observed SAE ARP9013 - 9 - 2.3 (Continued): COMBINATIONS: The number of distinct groupings of m distinct objects taken i at a time, where order of selection is immaterial, as 123, 321, and 213. ()! imi!m!im=(Eq. 3) w here: m! = m (m-1) (m-2) 3 2 1 CONFORMANCE: When a characteristic of a product or process meets its requirements. Fulfillment of specified requirements. Also called “Conformity.” CONSUMERS RISK: The probabilit
