Question

04)- 244+3-15 marás) Control charts for X and R are mairnt S marks) Contr ol charts for X and R are maintained for quality characteristic. The and R are computed for each sample. After 30 samples, the following a computed: 6690 R-1030 a- What are the tria Ilimits for the R chart ? tb) Assuming that the R chart is in control, what are the trial limits for the X char? Estimate the process mean and standard devintion. (d- Ifthe quality eharacterintle s mormally distributed and specification timits are 220 a 35,estimate the fraction nosconforming e Assuming that the variance remains constant, where should the process mean be located to minimize the fraction nonconforming?

Answer 1

G1i sample size,n=6 IVen A2 0.48 Sample, N = 30 22.534 しー[ UCLR =ĐạR= 2x3433 68-66 LCL Note g- Sample Sre'nこ6 4

30 6C 90 30 = 223 = 223 + 0.48 X34.33 239.4784 --A2R tcL5 = 223-(0.43x34.33) = 206.5218 CPrekesa =ろσ= 223 Is S Standad deviation, -R- ろ4.33 ㄒㄧ-253 -13.5 2 2-S34 223 34.3 43-5477 2. 2. 534 NI, Shaded Aewll be y de Ve 2.3 6 2 13.547'7

correypondingo above z,-2.369 Area Sini Mu n 13. 547 0.002 6-0.26% -0.4974 ס "Tota/メDefective 0.3,9% +0.29.
Note :- use normal distribution table for reading of Area corresponding to Z values in part d)