Relationships among various factors used in calculating control limits of control chart for variable data

계량형 관리도의 관리규격 계산에 사용되는 여러 계수값 사이의 관계

  • 박성균 (시그마트리즈 컨설턴트) ;
  • 김영균 (전주공업대학 시스템 정보경영과)
  • Published : 2002.12.01

Abstract

There are many different factors used in calculating control limits of control chart for variable data. Specially these factors are divided into two groups such as "no given standard" and "given standard"(namely, for analysis and management), but many kind of factors give rise to confusion. Therefore, It is necessary to manifest relationships among factors for easy application regardless of subgroup size. Many SQC textbooks show us plainly these factors, but do not have enough for adequate explanation of relationships among factors. Besides, notation of these factors of SQC textbook isn't coincide with another one, so necessity to the coincidence for the notation of the factors is highlighted during my work recently. In this study, the close examination about relationships among various factors (A-A3, B3-B6, D1-D4, C4, d2, d3 etc) was carried out. Spread sheet results are presented for getting factors according to subgroup size, by grouping as the case of "no given standard" and "given standard". How are these factors to be applied in statistical package (ex, Minitab) have been analyzed using a series of sample data. analyzed using a series of sample data.

Keywords

References

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