Deck 17: Process Improvement Using Control Charts

Question 1

Reducing common causes of variation usually requires action by management.

Answer 1

True

Question 2

Periodic sampling is observing the output of a process at random intervals.

Answer 2

False

Question 3

If a process is only influenced by common causes of variation,we can state that the process is in statistical control.

Answer 3

True

Question 4

A goal of statistical process control is continuous process improvement.

Question 5

A sequence of steadily decreasing points on a control chart is called run down.

Question 6

A range chart is a control chart in which ranges between individual process measurements within subgroup are plotted.

Question 7

How well the design of the product meets and exceeds the needs and expectations of the customers is called the quality of performance.

Question 8

A control chart is a graph whose purpose is to detect assignable causes of variation in a process.

Question 9

If a process is stable and in statistical control,it is not influenced by assignable causes of variation.

Question 10

How well a process is able to meet the requirements set forth by the process design is called the quality of design.

Question 11

Process leeway is the distance between natural tolerance limits and control limits.

Question 12

If a manufacturing process is in statistical control,it means that the process is capable of producing products that meets the customer's needs.

Question 13

For a given control chart,zone boundaries consist of UCL and LCL.

Question 14

An chart is a control chart on which individual process measurements are plotted versus time.

Question 15

Unusual sources of variation that can be attributed to specific causes are called the common causes of process variation.

Question 16

When using and R charts to analyze and improve a process,first,the chart is analyzed and the necessary action(s)to correct assignable causes of variation is (are)taken before the R chart is analyzed.

Question 17

A p-chart is a control chart on which the proportions of nonconforming units are plotted versus time.

Question 18

Sigma level capability is the number of estimated process standard deviations between the estimated process mean and the specification limit closest to the estimated process mean.

Question 19

Cause and effect diagram enumerates the potential causes of an undesirable effect on the process to discover sources of process variation and to identify opportunities for process improvement.

Question 20

Control charts are used to reduce common causes of variation.

Question 21

The natural tolerance limits for a normally distributed process that is in statistical control:

A)Extend beyond the specification limits when a process is capable
B)Are within the specification limits when a process is capable
C)Contain approximately 99.73 percent of the individual process measurements
D)Both B and C are correct
E)Both A and C are correct

Question 22

When employing measurement data to study a process,the ______ monitors the process mean.

A)
B)p-bar-chart
C)R chart
D)Natural tolerance
E)Pattern analysis

Question 23

Consider two processes.Process 1's mean is equal to its target (nominal)value,while the process 2's mean is not equal to its target value.The Cpkvalue for process 1 will _____,Cpkvalue for process 2.

A)Always be larger than
B)Always be the same as
C)Always be smaller than
D)Sometimes be larger than
E)Sometimes be smaller than

Question 24

In a manufacturing process,if the limits for a control chart are set too _____________,the risk of not investigating a special cause of variation and possibly not taking a corrective action ____________.

A)Tight,increases
B)Loose,increases
C)Loose,decreases
D)None of the above

Question 25

As the standard deviation of a process ___________,the process capability measured by Cpk________.

A)Decreases,decreases
B)Increases,increases
C)Decreases,increases
D)None of the above

Question 26

Rational subgrouping allows us to detect changes _____ subgroups.

A)Within
B)Between
C)In the sizes of
D)None of the above

Question 27

In a manufacturing process,if the limits for a control chart are set too _____________,the risk of unnecessarily tampering with the process ____________.

A)Tight,increases
B)Loose,increases
C)Tight,decreases
D)None of the above

Question 28

Common causes of process variation:

A)Are sources of unusual process variation
B)Usually must be remedied by management
C)Usually must be remedied by local supervision
D)Always exist together with assignable causes of variation
E)Can never be remedied or reduced

Question 29

Observing the output of a process at fixed time intervals is referred to as _____ sampling.

A)Consecutive
B)Random
C)Fixed
D)Periodic

Question 30

How well a product or service performs in the marketplace is called:

A)Process capability
B)Quality of conformance
C)Quality of performance
D)Quality of design
E)Process control

Question 31

When employing measurement data to study a process,the _______ monitors the process variation.

A)
B)R chart
C)p chart
D)natural tolerance
E)pattern analysis

Question 32

How well a process is able to meet the requirements set forth by the process design is called

A)Process leeway
B)Quality of conformance
C)Quality of performance
D)Quality of design

Question 33

_______ chart monitors the number of nonconformities units in a subgroup.

A)
B)R
C)C
D)P

Question 34

Which one of the following control charts is designed to control the proportion of nonconforming units?

A)p-charts
B)
C)R-chart

Question 35

If the process variability steadily increases,we would observe

A)An alternating pattern of high value followed by a low value on the R-chart.
B)An upward trend on the R-chart.
C)A downward trend on the R-chart.
D)An increasing gradual funnel pattern on the R-chart.
E)A decreasing gradual funnel pattern on the R-chart.

Question 36

Common causes of variation represent the inherent variability of a given process.

Question 37

If a control chart is used correctly,and the necessary corrective actions are taken,as the control limits get _______,the potential quality of the product _____________.

A)Looser,increases
B)Tighter,decreases
C)Tighter,increases
D)None of the above

Question 38

When a process is influenced only by common causes of variation:

A)The process may also be influenced by assignable causes of variation.
B)Many plot points on a control chart will be outside the control limits.
C)The process is always capable of meeting customer requirements.
D)The process is in statistical control.
E)The process is never capable of meeting customer requirements.

Question 39

How well the design of a product or service meets and exceeds the needs and expectations of the customer is called

A)Process capability
B)Quality of conformance
C)Quality of performance
D)Quality of design
E)Process control

Question 40

If a company is using an chart for a given process with measurement data,it is generally not important or necessary to use an R or s chart.

Question 41

A powder metal manufacturing company is producing sleeves for a locking mechanism.The target (nominal)value for the inside diameter is 1 inch.The inside diameter specifications are 1 $\pm$ .005 inches.Assume that the process is in statistical control with = 1.0002 inches, = .003 inches and subgroup size of 5. Calculate the control limits for the chart.

A).99781 to 1.00219
B).99801 to 1.00238
C).99830 to 1.00713
D).99847 to 1.00193
E).995 to 1.005

Question 42

A powder metal manufacturing company is producing sleeves for a locking mechanism.The target (nominal)value for the inside diameter is 1 inch.The inside diameter specifications are 1 $\pm$ .005 inches.Assume that the process is in statistical control with = 1.0002 inches, = .003 inches and subgroup size of 5. What is the sigma level capability for this process?

A)3.0
B)3.72
C)1.6
D)1.0
E)2.72

Question 43

A powder metal manufacturing company is producing sleeves for a locking mechanism.The target (nominal)value for the inside diameter is 1 inch.The inside diameter specifications are 1 $\pm$ .005 inches.Assume that the process is in statistical control with = 1.0002 inches, = .003 inches and subgroup size of 5. Determine the estimated number of standard deviations of process leeway.

A)3
B)1.667
C)3.72
D)1.443
E).72

Question 44

A sequence of steadily increasing plot points on a control chart is referred to as a _____.

A)funneling
B)run up
C)cycle
D)out of control

Question 45

In 25 samples of 100 units each,75 units were found to be defective.Find the appropriate UCL and LCL for the p-chart.

A)0 to .0642
B)0 to .0828
C)0 to .0812
D).0129 to .0471
E)0 to .1324

Question 46

A _____ is a set of process observations that are examined for the purpose of constructing control charts.

A)Subgroup
B)Sample
C)Zone
D)Common causes

Question 47

Auxiliary lines drawn on a control chart for accomplishing pattern analysis are called _____ boundaries.

A)sigma
B)range
C)zone
D)mean

Question 48

For a manufacturing process, = 10 inches, = .4 inches and the subgroup sample size is 6 units. Calculate the standard control limits for the chart.

A)9.526 and 10.474
B)9.769 and 10.231
C)9.807 and 10.193
D)9.484 and 10.516
E)8.80 and 11.20

Question 49

A powder metal manufacturing company is producing sleeves for a locking mechanism.The target (nominal)value for the inside diameter is 1 inch.The inside diameter specifications are 1 $\pm$ .005 inches.Assume that the process is in statistical control with = 1.0002 inches, = .003 inches and subgroup size of 5. Calculate the estimated proportion of out of specification sleeve inside diameters.

A).0471
B).0217
C).4861
D).4783
E).0139

Question 50

A control chart on which subgroup means are plotted versus time is a(n)_____ chart.

A)
B)R
C)p
D)C

Question 51

A control chart on which subgroup ranges are plotted versus time is a(n)_____ chart.

A)
B)R
C)p
D)C

Question 52

Sources of process variation that are inherent to the process design are called _____ causes of variation.

A)common
B)assignable
C)unusual
D)expected

Question 53

A powder metal manufacturing company is producing sleeves for a locking mechanism.The target (nominal)value for the inside diameter is 1 inch.The inside diameter specifications are 1 $\pm$ .005 inches.Assume that the process is in statistical control with = 1.0002 inches, = .003 inches and subgroup size of 5. What are the natural tolerance limits for this process? Is the process capable?

A).99847 to 1.00193,yes
B).99847 to 1.00193,no
C).99633 to 1.004,yes
D).99633 to 1.004,no
E).995 to 1.005,yes

Question 54

_____ causes of variation may be remedied by local supervision.

A)Common
B)Assignable
C)Usual
D)Expected

Question 55

For a manufacturing process, = 10 inches, = .4 inches and the subgroup sample size is 6 units. Calculate the natural tolerance limits for this process.

A)9.526 to 10.474
B)9.510 to 10.490
C)9.484 to 10.516
D)9.807 to 10.193
E)9.769 to 10.231

Question 56

_____ is the sigma level capability divided by three.

A)Process leeway
B)C_pk index
C)R/d₂
D)p

Question 57

For a manufacturing process, = 10 inches, = .4 inches and the subgroup sample size is 6 units. Calculate the standard control limits for the R chart.

A)0 and .846
B)0 and .802
C)0 and .77
D)0 and 1.0
E)-.09 and .89

Question 58

If a control chart is used correctly and the necessary corrective actions are taken,then as the control limits get close to each other,the potential quality of the product _____________.

A)decreases
B)increases
C)stays the same
D)fluctuates

Question 59

If the ________ limits are within the ________ limits,then it can be concluded that the process is __________.

A)Specification,natural,capable
B)Natural,specification,stable
C)Specification,natural,stable
D)Natural,specification,capable

Question 60

A control chart on which the proportions of nonconforming units in subgroups of size n are plotted versus time is a _____ chart.

A)
B)R
C)p
D)C

Question 61

_________ is the international standards on quality management and quality assurance systems.It establishes processes for assuring that goods and services offered by the company meet a consistent level of quality acceptable to customers.

A)C_pk Index
B)SQC
C)ISO 9000
D)ASQC

Question 62

If and R charts are used to control a manufacturing process,______ chart is analyzed first and brought into a state of statistical control before preparing the _______ chart.

A)R,
B)

Question 63

A unit that fails to meet specifications is called a _____ unit.

A)conforming
B)capable
C)defective
D)common cause

Question 64

If 20 samples of size 7 are drawn with = 33.33 and = 5.65. What are the UCL and the LCL for the chart?

A)(32.313 34.347)
B)(30.693 35.697)
C)(27.68 38,98)
D)(32.911 33.749)

Question 65

If 20 samples of size 7 are drawn with = 33.33 and = 5.65, What is the A-B upper boundary for the chart?

A)35.697
B)34.908
C)34.347
D)34.008

Question 66

The distance between natural tolerance limits and customer specifications is called _____.

A)process leeway
B)sigma level
C)C_pk Index
D)zone

Question 67

If = .0139 and 25 shipments of 20 items each were examined,what is the UCL and the LCL for the p-chart?

A)(.0118 .0159)
B)(0 .0401)
C)(.008 .0198)
D)(0 .0924)

Question 68

A(n)_____ process has the ability to produce products or services that meet customer requirements.

A)in control
B)assignable
C)capable
D)statistical

Question 69

If = 5.2, = .3,and n = 4,and if specifications are (4.6,5.8),is the process capable?

A)Yes
B)No

Question 70

A systematic method for analyzing process data in which we monitor process variation is called _____.

A)control charting
B)sigma level capability
C)statistical process control
D)rational subgrouping

Question 71

If = 2.0144, = .0972,and 25 subgroups of size 5. Find the UCL and the LCL for the R-chart.

A)(.045 .1498)
B)(.0972 .2055)
C)(0 .2055)
D)(0.2,114)

Question 72

How well a process is able to meet the requirements set forth by the process design is called the quality of _____________.

A)performance
B)conformance
C)design
D)control

Question 73

If 20 samples of size 7 are drawn with = 33.33 and = 5.65, What are the UCL and LCL for the R-chart?

A)(2.345 8.955)
B)(.076 1.924)
C)(.415 1.585)
D)(.429 10.871)

Question 74

The number of estimated process standard deviations between and the closest specification limit is the ______ of the process.

A)sigma level capability
B)leeway
C)C_pk Index
D)capability

Question 75

If = 16.1, = .03,and n = 6,and if specifications are (15.9,16.3),is the process capable?

A)Yes
B)No

Question 76

If = 2.0144, = .0972,and 25 subgroups of size 5. Find the UCL and the LCL for the chart.

A)(1.999 2.029)
B)(1.958 2.071)
C)(1.917 2.112)
D)(1.437 2.591)

Question 77

How well a product or a service performs in the market place is called the quality of ______________.

A)performance
B)conformance
C)design
D)control

Question 78

If = 5.2, = .3,and n = 4,calculate natural tolerance limits.

A)(5.054 5.346)
B)(4.3 6.1)
C)(4.806 5.594)
D)(4.763 5.637)

Question 79

Unusual sources of process variation that can be attributed to specific reasons are called _____ causes of variation.

A)common
B)assignable
C)usual
D)expected

Question 80

If = 16.1, = .03,and n = 6,calculate natural tolerance limits.

A)(16.065 16.135)
B)(16.088 16.112)
C)(15.745 16.455)
D)(16.055 16.145)