Question 1

Ten high-technology batteries are tested for 200 hours each. One failed at 50 hours; all others completed the test. FR(%) is __________ and FR(N) is __________.

Accepted Answer

A)  10%; 1/1850 
B)  10%; 1/2000 
C)  25%; 1850 hours 
D)  90%; 1/2000 
E)  Indeterminate; no standard deviation is given. 
A)  10%; 1/1850 
B)  10%; 1/2000 
C)  25%; 1850 hours 
D)  90%; 1/2000 
E)  Indeterminate; no standard deviation is given.

Question 2

Is there an optimal amount of preventive maintenance?
 What caution should be exercised before calculating this optimal amount?

Accepted Answer

Too little preventive maintenance causes

Question 3

Which product design below has the higher system reliability?

Accepted Answer

A's reliability is .98 * .99 *

Question 4

__________ is the expected time between a repair and the next failure of a component, machine, process, or product.

Accepted Answer

Mean time

Question 5

Which of the following increase as repairs move from the maintenance department to the depot service?

Accepted Answer

A)  cost 
B)  replacement time 
C)  quality 
D)  employee ownership 
E)  A, B, and C 
A)  cost 
B)  replacement time 
C)  quality 
D)  employee ownership 
E)  A, B, and C

Question 6

Why is it that many cost curves associated with maintenance rarely consider the full cost of a breakdown?

Accepted Answer

Many costs are ignored because they are

Question 7

__________ is the failure rate early in the life of a product or process.

Accepted Answer

The answer of __________ is the failure rate early in...

Question 8

Ten high-intensity bulbs are tested for 100 hours each. One failed at 40 hours; all others completed the test. Calculate FR(%) and FR(N).

Accepted Answer

FR(%) = 1/10 or 10%;

Question 9

A manager is comparing the total maintenance (preventive plus breakdown) cost curves for two scenarios. The graphs have maintenance commitment on the x-axis and costs on the y-axis. Scenario A includes the direct breakdown maintenance costs, while Scenario B includes the "full" (direct and indirect) breakdown maintenance costs. Which of the following should the manager notice when going from Scenario A to Scenario B?

Accepted Answer

A)  total cost is decreased 
B)  optimal point is moved to the left 
C)  optimal point is moved to the right 
D)  preventative maintenance cost slope is increased 
E)  none of the above 
A)  total cost is decreased 
B)  optimal point is moved to the left 
C)  optimal point is moved to the right 
D)  preventative maintenance cost slope is increased 
E)  none of the above

Question 10

As the number of components in a system connected in a series decreases, all other things being equal, the reliability of the system usually

Accepted Answer

A)  increases 
B)  stays the same 
C)  decreases 
D)  increases, then decreases 
E)  decreases, then increases 
A)  increases 
B)  stays the same 
C)  decreases 
D)  increases, then decreases 
E)  decreases, then increases

Question 11

Which of the following is a reliability tactic?

Accepted Answer

A)  improving individual components 
B)  increasing repair speed 
C)  providing redundancy 
D)  A and C 
E)  A, B, and C 
A)  improving individual components 
B)  increasing repair speed 
C)  providing redundancy 
D)  A and C 
E)  A, B, and C

Question 12

What is breakdown maintenance?

Accepted Answer

Breakdown maintenance is the r

Question 13

A product is composed of a series connection of four components with the following reliabilities. What is the reliability of the system?
 $\begin{array}{|l|c|c|c|c|}
\hline\text { Component } & 1 & 2 & 3 & 4 \
\hline \text { Reliability } & .90 & .95 & .97 & .88 \
\hline
\end{array}$

Accepted Answer

The reliability of t

Question 14

The MTBF distributions of products, machines, or processes that have "settled in," or gone beyond the infant mortality phase, often follow the normal distribution.

Accepted Answer

A) True 
 B)False

Question 15

An oil change is to ____________ maintenance as repair of a broken alternator is to ____________ maintenance.

Accepted Answer

A)  preventive, breakdown 
B)  breakdown, preventive 
C)  preventive, preventive 
D)  breakdown, breakdown 
E)  none of the above 
A)  preventive, breakdown 
B)  breakdown, preventive 
C)  preventive, preventive 
D)  breakdown, breakdown 
E)  none of the above

Question 16

Small standard deviations in the MTBF distribution of a machine tend to support a policy of breakdown maintenance for that machine.

Accepted Answer

A) True 
 B)False

Question 17

Ten high-technology batteries are tested for 200 hours each. One failed at 20 hours; another failed at 140 hours; all others completed the test. FR(%) is __________ and MTBF is __________.

Accepted Answer

A)  20%; 880 hours 
B)  10%; 1980 hours 
C)  20%; 1760 hours 
D)  cannot calculate from information provided 
E)  80%; 920 hours 
A)  20%; 880 hours 
B)  10%; 1980 hours 
C)  20%; 1760 hours 
D)  cannot calculate from information provided 
E)  80%; 920 hours

Question 18

Identify the two reliability tactics and the two maintenance tactics.

Accepted Answer

Reliability tactics are improv

Question 19

Consider a product that is "settled in." Its MTBF distribution has been found to be normal with a mean of 1,000 hours and a standard deviation of 250 hours. What is the probability of a breakdown before 750 hours?
 Before 500 hours?
 Would you prefer a policy of preventive maintenance, or a policy of breakdown maintenance, on this product?
 Explain your choice.

Accepted Answer

Failure probabilities are not negligible

Question 20

Suppose that a car mechanic offers you a deal that for the next 3 years any breakdowns will be covered, so long as you bring your car in for $50 preventative maintenance sessions each month. If you predict the likelihood of a breakdown being 25% without the maintenance, how much must a breakdown cost for you to prefer the preventative maintenance?

Accepted Answer

36 months * $50/mont

Exam 20: Maintenance and Reliability

Ten high-technology batteries are tested for 200 hours each. One failed at 50 hours; all others completed the test. FR(%) is __________ and FR(N) is __________.

Is there an optimal amount of preventive maintenance? What caution should be exercised before calculating this optimal amount?

Which product design below has the higher system reliability?

__________ is the expected time between a repair and the next failure of a component, machine, process, or product.

Which of the following increase as repairs move from the maintenance department to the depot service?

Why is it that many cost curves associated with maintenance rarely consider the full cost of a breakdown?

__________ is the failure rate early in the life of a product or process.

Ten high-intensity bulbs are tested for 100 hours each. One failed at 40 hours; all others completed the test. Calculate FR(%) and FR(N).

As the number of components in a system connected in a series decreases, all other things being equal, the reliability of the system usually

Which of the following is a reliability tactic?

What is breakdown maintenance?

A product is composed of a series connection of four components with the following reliabilities. What is the reliability of the system? Component 1 2 3 4 Reliability .90 .95 .97 .88

The MTBF distributions of products, machines, or processes that have "settled in," or gone beyond the infant mortality phase, often follow the normal distribution.

An oil change is to ____________ maintenance as repair of a broken alternator is to ____________ maintenance.

Small standard deviations in the MTBF distribution of a machine tend to support a policy of breakdown maintenance for that machine.

Ten high-technology batteries are tested for 200 hours each. One failed at 20 hours; another failed at 140 hours; all others completed the test. FR(%) is __________ and MTBF is __________.

Identify the two reliability tactics and the two maintenance tactics.

Operations and Productivity

Operations Strategy in a Global Environment

Project Management

Forecasting

Design of Goods and Services

Managing Quality

Statistical Process Control

Process Strategy

Capacity and Constraint Management

Location Strategies

Layout Strategies

Human Resources, Job Design, and Work Measurement

Supply-Chain Management

Outsourcing as a Supply-Chain Strategy

Inventory Management

Aggregate Planning

Material Requirements Planning MRP and ERP

Short-Term Scheduling

Just-In-Time and Lean Options

Decision-Making Tools

Linear Programming

Transportation Models

Waiting-Line Models

Learning Curves

Simulation

Filters

Ten high-technology batteries are tested for 200 hours each. One failed at 50 hours; all others completed the test. FR(%) is and FR(N) is .

An oil change is to maintenance as repair of a broken alternator is to maintenance.

Ten high-technology batteries are tested for 200 hours each. One failed at 20 hours; another failed at 140 hours; all others completed the test. FR(%) is and MTBF is .