Exam 13: Statistical Process Control

Describe a process where a p-chart could be used to monitor a quality characteristic.Clearly identify the nature of the quality characteristic and why the p-chart is appropriate.Suggest a sampling procedure to allow for rational sub-groups.

Each day,a manufacturing company producing circuit boards will randomly sample 60 circuit boards and then determine and plot the number of defects contained in each of these boards.The appropriate control chart is a:

Which of the following charts is used to monitor the total number of defects per unit when a constant subgroup size is employed?

A process fills boxes with detergent.Construct an appropriate set of control charts to monitor the filling process.Historical data for fill weight (in ounces)of eight samples are presented below.A sample size of six was used.

A p-chart is used with attribute data.

Define each of the following control chart patterns.Include a sketch of each pattern with your definition. a.One point outside the control limits b.Hugging the control limit c.Cycles d.Trends e.Hugging the centerline

A p-chart is also called a:

An alternative to using the R-chart is the:

Which of the following charts is used to monitor the average number of defects per unit when subgroup sizes vary?

A precision parts manufacturer produces bolts for use in military aircraft. The specifications for bolt length are $37.50 \pm 0.25 \mathrm{~cm}$ . The company has established an $\bar{x}$ -chart and an $R$ -chart using samples of size five. The centerlines for the $\bar{x}$ chart and $R$ -chart are set at $37.65 \mathrm{~cm}$ and $1.03 \mathrm{~cm}$ , respectively. What is the value of $C_{p}$ for this process?

c-charts are based on the _____ probability distribution.

x-charts are used for:

The s-chart is recommended when:

If all sample averages on an -chart fall within the control limits,all output will be conforming.

Identify the conditions that support the use of a control chart for individuals.Discuss any limitations associated with the chart use.

A histogram of data that resembles the normal distribution indicates that the process is in control.

The most commonly applied control limits for variables data are 3-sigma control limits.

A company wishes to monitor the variation in the length of time it takes to process and send a bill to a customer.Five bills will be randomly selected each day and the length of time it takes to process and send the bill to a customer will be recorded for each bill.The appropriate control chart is a(n):

Identify the tradeoffs associated with the s-chart instead of the R-chart.

Describe a process where a c-chart could be used to monitor a quality characteristic.Clearly identify the nature of the quality characteristic and why the c-chart is appropriate.Suggest a sampling procedure to allow for rational sub-groups.