Forword
This document is drafted in accordance with GB/T 1.1-2020 Guidelines for Standardization - Part 1: Structure and Drafting Rules of Standardization Documents.
This document is the first part of GB/T 18779 Geometrical Product Specifications (GPS) Measurement Inspection of Workpieces and Measuring Equipment. GB/T 18779 has issued the following parts:
Part 1: Judgment rules for qualified or unqualified verification according to specifications;
Part 2: Guide to the evaluation of measurement uncertainty in the calibration of GPS measurement equipment and product verification;
Part 3: Guidelines for reaching consensus on the expression of measurement uncertainty;
Part 4: Basis of functional limit and normative limit in decision rules;
Part 5: Test uncertainty of indicating measuring instruments;
Part 6: General rules for acceptance/rejection of instruments and workpieces.
This document replaces Part 1 of GB/T 18779.1-2002 Geometrical Product Specifications (GPS), Measurement Inspection of Workpieces and Measuring Equipment; The main technical changes are as follows, except for structural adjustment and editorial changes, compared with GB/T 18779.1-2002.
a) Changed the scope of the document (see Chapter 1, meaning 6 of the 2002 edition)
b) Deleted term:
Tolerance limit, tolerance, tolerance zone, maximum allowable error, gauge range, specification limit, upper specification limit, lower specification limit, measured, measurement result, nominal value, measurement uncertainty, standard uncertainty composite standard uncertainty, expanded uncertainty, inclusion factor, complete statement, qualified, qualified zone, unqualified, unqualified zone of measurement result (see 3.1~3.8, 3.10~3.22 of 2002 edition).
c) Added terms:
The acceptance probability limit, the default acceptance probability limit, the lower failure probability, the upper failure probability, the failure probability limit, the default failure probability limit receiving area, the default receiving area, the default rejection area, and the default rejection area (see 3.2~3.11).
d) The determination method has been changed, and the determination focus has been converted from the inclusion probability to the pass (or fail) probability (see 4.1
5.1)。
e) Replace the original default coverage factor k=2 with 95% of the default pass (or fail) probability, so as to ensure the judgment risk of pass judgment
Constant (see 4.2, 4.3, Chapter 4 of 2002 edition).
This document is equivalent to ISO 14253-1:2017 Geometrical Product Specifications (GPS) - Measurement and Inspection of Workpieces and Measuring Equipment - Part 1: Rules for Determining Conformity or Nonconformity in Verification according to Specifications.
Please note that some of the contents of this document may involve patents. The issuing agency of this document does not assume the responsibility of identifying the patent. This document is proposed and under the jurisdiction of the National Technical Committee for Standardization of Geometrical Product Specifications (SAC/TC 240).
Introduction
In order to reduce disputes between suppliers and customers in the acceptance process of workpieces and measuring equipment, reduce the cost of acceptance, improve the economic benefits of products, and better integrate with international trade rules, the acceptance strategy of workpieces and measuring equipment in China and the rules for determining whether they are qualified need to be studied and formulated urgently.
In order to adapt to China's reform and opening up situation and meet the needs of international trade, technology and economic exchanges, GB/T 18779 is equivalent to ISO 14253.
GB/T 18779 is a general standard for Geometrical Product Specifications (GPS) (see GB/T 20308), which affects the four links in the GPS standard matrix model link, namely, conformity and non conformity, measurement, measuring equipment and calibration.
GB/T 18779 is applicable to the basic rules of GPS given in GB/T 4249; Unless otherwise specified, the default decision rules given in this document apply to all GPS files.
GB/T 18779 mainly describes the acceptance strategy and acceptance judgment rules of tools and measuring equipment when measurement uncertainty is considered. For the convenience of readers, GB/T 18779 is divided into six parts. These six parts are both interrelated and independent, and together constitute the acceptance strategy and qualification determination rules of workpieces and measuring equipment.
Part 1: Judgment rules for qualified or unqualified verification according to specifications. The strategy of workpiece or measuring equipment qualification verification is given; gauge
The default judgment rule is set to consider the measurement uncertainty of the measured value and verify whether it is qualified according to the GPS specification of the workpiece or measuring equipment; According to the GPS specification, verify the possible handling conditions that can neither be determined as qualified nor unqualified—— Part 2: Guide to the evaluation of measurement uncertainty in GPS measurement, measurement equipment calibration and product verification. It is based on measurement
GPS Guide for Uncertainty Evaluation of Measurement (GUM); It provides the uncertainty management procedure (PUMA) and the practical method of measurement uncertainty evaluation, as well as the measurement uncertainty U. Meet the specified target uncertainty U, requirements (i.e. U:
Contents of GB/T 18779.1-2022
Forword
Introduction
1 Scope
2 Normative References
3 Terms and definitions
4 Default Decision Rules
5 Qualified or unqualified according to the specification
6 Application in the relationship between suppliers and customers
Appendix A (informative) Relationship between this edition and the previous edition
Appendix B (Informative) Relationship with GPS Matrix Model
Bibliography
