GB/T 18779.6-2020Geometrical product specifications(GPS). Inspection by measurement of workpieces and measuring equipment - Part 6: Generalized decision rules for the acceptance and rejection of instruments and workpieces (English PDF)

1 Scope

This part of GB/T 18779 gives the conditions when the default rules of GB/T 18779:1 may not be economically optimal:

Judgment rules:

Note 1: GB/T 18779:1 provides a default judgment rule: According to this rule, if the measured value characterizes the acceptance of a product, it has a high probability of

Ensure that the corresponding measurement of the product meets the specifications:

Note 2: To change the judgment rule from the default rule to a rule for a specific task, the parties concerned need to reach an agreement:

This section does not deal with how to determine the cost of correct or incorrect judgment ("correct judgment" means accepting qualified products or rejecting unqualified

“Wrong judgment” means accepting unqualified products or rejecting qualified products), because this is a business matter: However, this section gives

The required terminology and requirements are used to communicate and implement specific judgment rules, while giving examples of guiding applications:

Note 3: The determination rules of this section apply to the single measurement characteristic under consideration: Unless otherwise stated, all probability distributions discussed in this section are Gaussian

It is distributed and located in the center, and the cost function is a simple step function: However, the principles of this section can be applied to any probability distribution function or

This function:

This section applies to the measurement and inspection of workpieces and measuring equipment in product geometric technical specifications, as well as industrial applications:

2 Normative references

The following documents are indispensable for the application of this document: For dated reference documents, only the dated version applies to this article

Pieces: For undated references, the latest version (including all amendments) applies to this document:

GB/T 18779:1 Technical Specification for Product Geometrical Quantity (GPS) Measurement Inspection of Workpieces and Measuring Equipment Part 1: Inspection According to Specifications

Rules for determining qualified or unqualified inspection (GB/T 18779:1-2002, eqvISO 14253-1:1998)

GB/T 24634 Product Geometric Technical Specification (GPS) General concepts and requirements for GPS measuring equipment (GB/T 24634-2009,

ISO 14978:2006, IDT)

GB/T 24637:2 Product Geometric Technical Specification (GPS) General Concepts Part 2: Basic Principles, Specifications, Operational Sets and Uncertainties

Fixed degree (GB/T 24637:2-2020, ISO 17450-2:2012, MOD)

JJF1001 General measurement terms and definitions

JJF1059:1 Evaluation and expression of measurement uncertainty

3 Terms and definitions

GB/T 18779:1, GB/T 24634, GB/T 24637:2, JJF1001, JJF1059:1 and the following terms and definitions are applicable

Used in this document:

3:1

Acceptancelimit

The upper or lower limit of the allowable measured value:

GB/T 10932 | GB/T 22092 | GB/T 26093 | GB/T 18779.3 | GB/T 18779.2 | GB/T 18779.1 | […]