# Question: Parts manufactured by an injection molding process are subjected to

Parts manufactured by an injection molding process are subjected to a compressive strength test. Twenty samples of five parts each are collected, and the compressive strengths (in psi) are shown in Table 6E.12.

(a) Establish x and R control charts for compressive strength using these data. Is the process in statistical control?

(b) After establishing the control charts in part (a), 15 new subgroups were collected and the compressive strengths are shown in Table 6E.13. Plot the x and R values against the control units from part (a) and draw conclusions.

(a) Establish x and R control charts for compressive strength using these data. Is the process in statistical control?

(b) After establishing the control charts in part (a), 15 new subgroups were collected and the compressive strengths are shown in Table 6E.13. Plot the x and R values against the control units from part (a) and draw conclusions.

**View Solution:**## Answer to relevant Questions

Reconsider the data presented in Exercise 6.21. (a) Rework both parts (a) and (b) of Exercise 6.21 using the x and s charts. (b) Does the s chart detect the shift in process variability more quickly than the R chart did ...Samples of size n = 5 are collected from a process every half hour. After 50 samples have been collected, we calculate. x = 20.0 and s 1.5. Assume that both charts exhibit control and that the quality characteristic is ...Samples f n= 5 units are taken from a process every hour. The x and R values for a particular quality characteristic are determined. After 25 sample have been collected, we calculate x =20 and R = 4.56. (a) What are the ...The data in Table 6E.17 were collected form a process manufacturing power supplies. The variable of interest is output voltage, and n = 5. (a) Compute center lines and control limits suitable for controlling future ...Consider the chart defined in Exercise 6.48. Find the ARL1 for the chart.Post your question