Assignment(s):

1. Read the provided text: Chapters 5, 6, and 6s.

2. Read the provided PowerPoint Slides for Chapters 5, 6 & 6s.

3. Submit solutions to the following textbook problems.
Chapter 5: Problems 4 & 9. Chapter 6: Discussion Question 4 and Problems 1 & 3. Chapter 6s: Problems 5, 21 & 22. 4-page total.

4. Separately, develop a 1 page proposal to identify an operational improvement discuss what you plan to study and improve (Obviously just use creative writing). Also, see attached separate instructions.

Chapter 5: Problems 4 & 9 page 164 and 166   

 

Question 4:

The Carry-on Luggage Company must set up an assembly line for a wheeled carry-on

bag. Forecasts show that 60 units per hour should be produced. The tasks required,

task times, and precedence relationships are as follows:

 

 

Task      Time (seconds)      Predecessors

A             30                              –

B             50                             A

C             25                             A

D            10                              B

E             25                             B

F             15                             B

G            10                             C, E, F

H            30                             D,G

 

  1. Draw the precedence diagram.
  2. What is the takt time?
  3. What is the theoretical number of workstations?
  4. Assign the tasks to the workstations to balance the line using the longest

operating time rule.

  1. What is the efficiency of the balanced line?

Question 9:

The Office Interiors Company has developed a new, modern office chair. Initial sales

forecasts are for 50 chairs per day. The assembly operations will run for two eight-hour

shifts. The process engineer and operations manager are working together to balance

the line to make the new chair as efficiently as possible. The process engineer suggests

using the longest operating time rule while the operations manager suggests using

the greatest number of followers rule to design the line. If there is a tie, use the other

rule to break the tie.

 

 

 

Task              Time (Minutes)      Predecessor

A                      7                              –

B                      12                            A

C                      6                              B

D                     13                             –

E                      8                              C, D

F                      10                             –

G                     4                               F

H                     10                            E,G

 

  • Based on the processing information, which approach do you recommend? Why?

 

 

 

 

 

Chapter 6: Discussion Question 4 page 191 and Problems 1 & 3 page 192-193 

 

Discussion Question 4:

It has been said that quality management is really a “people” system, more than a

technical system. If this is true, what conditions must first be in place for a firm to be

successful with quality management? What are the possible repercussions for the firm if the employees

aren’t committed to the quality management program?

 

Problem 1:

Given the following cost information for Company XYZ, calculate:

  1. Total appraisal cost
  2. Total prevention cost
  3. Total cost of internal failures
  4. Total cost of external failures
  5. Total cost of quality

 

Cost item                                                                      Total for the Year

Quality assurance                                                         $450,000

Equipment maintenance                                             $205,000

Product redesign                                                          $310,000

Product warranty and repair                                      $550,000

Product testing and inspection                                  $372,000

Training                                                                          $250,000

Process improvement/Kaizen                                    $120,000

Material scrap                                                               $230,000

Rework labor                                                                 $426,000

Incoming materials inspection                                   $323,000

Customer support (after sale)                                    $150,000

Travel to suppliers/process certification                  $75,000

Travel to customers/problem solving                       $80,000

 

Problem 3:

Six Sigma quality (3.4 defects per million units produced) is probably a bit much to

ask of Rachel’s old oven (see problem 2).

 

  1. What would the standard deviation in the temperature of her oven need to be if

she settled for a “Three Sigma” level of quality?

 

  1. If her oven exactly meets a “Three Sigma” quality level, what percentage of the

time would her oven be operating at a temperature outside the acceptable range?

(Hint: See Table 6-5 on page 185)

 

Chapter 6s: Problems 5, 21 & 22 pages 225, 228-229

 

Problem 5:

 

The specification for the weight of a box of cereal is 16.2 oz± .1 oz. The actual mean

and standard deviation from a sample of 200 boxes is 16.1 oz. and 0.05 oz., respectively.

  • What is the CP and Cpk?

 

Problem 21:

Peerless Windows is a major manufacturer and installer of windows into new homes.

Currently, management has found that it has experienced a large number of customer

claims (about 15% of all orders placed) against Peerless. These customers, often builders,

are claiming that they are receiving shipments of windows that are built to the

wrong specifications. Correcting these errors has cost Peerless a great deal in terms of

time, resources, and disrupted schedules. To determine if the order entry process is at

fault, management has collected orders from the last two years. For each month, 100

orders were withdrawn and reviewed. The results are summarized in the table below.

Experience with this product has resulted in the mean defect rate being 7.5 with the

LCL being 0 and the UCL being 15.

 

  • As an analyst, you have been asked to review the order entry process with the goal of assessing whether this process is causing the problems. Is this process causing a problem? If so, why?

 

 

 

 

Problem 22:

You are concerned about the quality of parts that you are rece1vmg from your

supplier. Consequently, you decide to take 25 batches of samples (where each sample

consists of 50 units) and conduct a 100% inspection on these samples. The results are

summarized below.

This forms the basis for your further analysis. Next, you collect information about

20 recent orders that you have received from your supplier in the last month. By the

way, it is important to note that your supplier is aware that your firm is concerned

about the quality of its parts. These are summarized below:

 

  1. Given the information in this problem, calculate the p, UCL, and LCL from the

baseline data. Use these parameters to construct a p attribute control chart.

 

  1. Plot the data from the June samples on the p chart derived in (a). What issues, if

any, does this analysis reveal? What management actions would you recommend

and why?

 

  1. You receive a telephone call from your supplier informing you that it (the

supplier) has significantly changed the production process for your orders at its

facility. How would this affect the previous analysis (p control chart)?

Operations Management