Statistical Process Control - Level 2 1. Vacuum pumps are being audited to determine if the process is in control and also capable of meeting the customer specifications. Samples of size n=5 are taken each hour of the day and tested with the data on vacuum recorded. The results of 10 consecutive hours of testing are provided. Sample # Observ. Observ, Observ. Observ. Observ. (by hour) 1 16 2 R 17 19 LAUA 18 16 10 15 12 (a) Find the x and R of each sample and record above. (b) Find and record the grand mean (x) and R in the appropriate boxes. (c) Find the UCL and LCL for the x chart. (d) Find the UCL and LCL for the R chart. (e) Sketch out a control chart for the x-bar chart. Is the process in control in terms of the "average" vacuum pressure? Yes or No (f) Sketch out a control chart for the R chart. Is the process in control in terms of the "variation" in the process? Yes or No (g) Find the process standard deviation (6). (h) Find the appropriate process capability index for the process if the lower and upper specification limits are 8 to 20. (1) What is your interpretation of the capability index