GB/T 17989.5-2022Statistical method of quality control in production process - Control charts - Part 5: Specialized control charts (English PDF)

foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for Standardization Work Part 1.Structure and Drafting Rules of Standardization Documents"

drafted.

This document is part 5 of GB/T 17989.GB/T 17989 has released the following parts.

--- Control Charts Part 1.General Guidelines;

--- Control Charts Part 2.General Control Charts;

--- Control Charts Part 3.Acceptance Control Charts;

--- Control Charts Part 4.Cumulative and Control Charts;

--- Statistical method control charts for quality control in production processes - Part 5.Special control charts;

--- Statistical method control charts for quality control in production processes Part 6.Exponentially weighted moving average control charts

--- Statistical method control chart for quality control in production process Part 7.Multivariate control chart;

--- Statistical method control chart for quality control in production process Part 8.Control method for short cycle and small batch;

--- Statistical methods for quality control of production process control charts Part 9.Stationary process control charts.

This document is modified and adopted ISO 7870-5.2014 "Control Charts - Part 5.Special Control Charts".

The structural differences between this document and ISO 7870-5.2014 and their reasons are as follows.

--- Increase the chapter number of the suspension section in Chapters 6 to 15, and adjust the number of other chapters to meet the requirements of national standards.

The technical differences between this document and ISO 7870-5.2014 and their reasons are as follows.

--- Added "7.5.2 Explanation From Figure 2, it can be seen that the points corresponding to the 11th, 24th, 26th, and 27th subgroups fall outside the control limits, and further investigations are required.

The reason for the out-of-control process", the original text lacks explanation;

---Added the description that the data does not obey the normal distribution (see 12.1), "If the data does not obey the normal distribution, you should first find out that the data does not obey the normal distribution.

If it is confirmed that the data obeys some other distribution, the upper and lower bounds are constructed according to its distribution", the original description

unclear;

--- Added Figure 7 (see 12.3.1) to test the normality of the data, indicating that it does not obey the normal distribution.

state test;

--- Added "Fig. 13 Mean Range Chart" (see 15.10.2), the original text lacks a diagram.

The following editorial changes have been made to this document.

--- Change the standard name to "Production Process Quality Control Statistical Methods Control Chart Part 5.Special Control Chart";

---In 10.5.3 "x=

i=1

xi

25 =

49.440

25 = 1.9776

" to "x=

i=1

xi

25 =

49.440

25 = 1.9776

";

--- Change "variation coefficient nu" in Chapter 11 to "variation coefficient CV";

---Change "UCL=x 99.865percentilexsaverage" in 12.2.3.3 to "UCL=x z99.865xsaverage", "LCL=

x 0.135percentilexsaverage" is changed to "LCL=x z0.135xsaverage";

---Change "B3=0.0284" in 12.3.2.1 to "B3=0.284";

--- The original z column data in Table 9 in 13.4.1 is incorrectly calculated, and all should be revised;

--- Put "ci=sum in 14.4

j=1

cij " to "ci=sum

j=1

cij ";

--- Replace "UCL=d 3 sum in 14.8.1

i=1

w2ici

Nnj

1/2

=1.203

4250x177

1/2

4.02 3.25=7.45" changed to

"UCL=d 3

i=1

w2ici

Nn

=4.203

4250x177

=4.20 3.25=7.45";

--- Delete "these values of a and b are used to calculate the upper and lower measurement limits" in the original 15.1;

--- Modify the data "20.47" of the 18th subgroup of the average column of Table 12 in 15.10.1 to "20.32", the 18th of the range column

The data "2.49" of the subgroup is modified to "2.96".

Please note that some content of this document may be patented. The issuing agency of this document assumes no responsibility for identifying patents.

Introduction

Control charts are commonly used statistical tools in process control to monitor deviations in the process and keep the process stable. GB/T 17989 control

Figure series standards are divided into the following 9 parts.

--- Control Charts Part 1.General Guidelines. The purpose is to give the basic terms, principles and classification of control charts, as well as the selection of control charts.

guide.

--- Control charts Part 2.General control charts. The purpose is to establish guidelines for process control using conventional control charts.

--- Control charts Part 3.Acceptance control charts. The purpose is to establish guidelines for the use of acceptance control charts for process control, and to specify

General procedure for determining subgroup sample sizes, action limits, and decision criteria.

--- Control Charts Part 4.Cumulative and Control Charts. The purpose is to establish the application of cumulative sum techniques for process monitoring, control and retrospective

Statistical methods of analysis.

--- Statistical methods for quality control of production process control charts Part 5.Special control charts. The purpose is to establish the understanding and application of special

A guide to statistical process control with control charts.

--- Production process quality control statistical methods control charts Part 6.Exponentially weighted moving average control charts. The purpose is to establish

A guide to solving and applying exponentially weighted moving average (EWMA) control charts for statistical process control.

--- Statistical methods for quality control of production process control charts Part 7.Multivariate control charts. The purpose is to establish the construction and application of diversity

Control charts are guidelines for statistical process control and establish routines for the use and understanding of multivariate control charts for measurement data.

--- Statistical methods of production process quality control control chart Part 8.Control methods for short cycle and small batches. The purpose is to establish

When the group size is 1, the conventional metrology control chart is used to detect the method of short cycle and small batch production process.

--- Statistical methods for quality control of production process control charts Part 9.Stationary process control charts. The purpose is to establish the construction and application

Control charts are guidelines for controlling stationary processes.

Conventional control charts given in GB/T 17989.2 can help monitor unnatural patterns of process-induced data variation and provide judgment

Criteria for whether the interrupt process is in statistical control. However, for metrological data, there are some special cases where using conventional control charts to

Unnatural patterns of process variation have problems of undetectable or low detection efficiency, as described in the following situations.

a) It takes a considerable amount of time to produce a product, and the time interval for sample acquisition is large;

b) There are multiple production processes to produce a product, and these production processes have approximately the same productivity, process average and process

ability;

c) the process average varies systematically;

d) The sample size is large and the order of production is irrelevant;

e) The process does not have a constant target value.

In the above situations, special control charts can be used.

Likewise, some special cases may be encountered when dealing with count data. In some cases, it may be desirable to focus on subgroups of

Severity, but different disqualifications have different degrees of severity. Therefore, all types of nonconformities cannot be treated equally. According to unqualified

It is necessary to give different weights to each type of unqualified, and calculate the corresponding defect score accordingly. Calculate control limits based on defect scores, and

Draw the corresponding control chart to control the process.

When controlling the positional and shape parameters of process measurable characteristics, in some cases, for practical reasons, there are counts

A situation in which inspection is preferred over metrological inspection (eg, inspection by means of a gauge). It may also be possible to obtain assembly operations below the lower specification limit (no

Pass gauge) and information on the quantity of product above the upper specification limit (pass gauge). In this case, an a,b chart can be used.

There may also be situations where the data do not follow a normal distribution. Except for special processes in the manufacturing industry, non-normal data in the service industry

also often encountered. In such cases, control charts for nonnormal data can be used.

The primary purpose of this document is to provide guidance on how to apply special control charts to process controls that address the typical special situations described above.

Production process quality control statistical method control chart

Part 5.Special Control Charts

1 Scope

This document describes guidelines for understanding and applying special control charts for statistical process control.

This document is suitable for situations where conventional control charts cannot detect unnatural patterns of process variation or are less efficient at detecting them.

For metrology data, the special control charts included in this document are.

a) moving average and moving range charts;

b) Z diagram;

c) group-based control charts;

d) extreme value control chart;

e) trend control chart;

f) Coefficient of variation control chart;

g) Control charts for nonnormal data.

For count data, the special control charts included in this document are.

a) normalized p control chart;

b) Defect control chart;

c) Gauge inspection control chart.

The guidance given in this document also includes the conditions of use, control limits, advantages and disadvantages, and examples of each type of control chart.

2 Normative references

The contents of the following documents constitute essential provisions of this document through normative references in the text. Among them, dated citations

documents, only the version corresponding to that date applies to this document; for undated references, the latest edition (including all amendments) applies to

this document.

GB/T 3358.2 Statistical vocabulary and symbols - Part 2.Applied statistics (GB/T 3358.2-2009, ISO 3534-2.2006,

IDT)

3 Terms and Definitions

The terms and definitions defined in GB/T 3358.2 and the following apply to this document.

3.1

control chart

A graph plotting a sequence of sample statistic values in a specific order to monitor, control, and reduce process variation.

Note 1.The specific order usually refers to the chronological order or the order in which the samples were obtained.

NOTE 2 Control charts are most effective when used to monitor characteristics about the final product or service.

[Source. GB/T 3358.2-2009, 2.3.1]