Operations and Quality Management

Academic Year 2019/20

ENG708s2 Operations and Quality Management

Second attempt Coursework

Deadline For Submission:

1 August 2020, 16:00

Instructions:

Answer all questions

Additional Information:

Turnitin submission

Provided:

Table A1 Standard normal distribution function – Attached

Some Important Formulae - Attached

Calculators:

Casio FX 85 Series or Casio FX 83 Series

Examiners:

Dr Ivan Popov

2019-20

1.

A company is considering the purchase of a machine to turn a shaft. A machine is borrowed for testing purposes, and it is found that 5.48% of the shafts have diameters greater than 5.032 mm when the machine is set at average 5.00 mm.

(a)

Give a graphical representation of the normal distribution probability in this case and calculate the standard deviation to which the machine is operating.

[9 Marks]

(b)

Assume that the company has managed to achieve and maintain process variation (based on 3σ) in a range of 0.12 mm and wishes to produce these shafts to a design dimension between 4.94 mm and 5.05 mm, and any shafts outside this range would be rejected. If the machine produces 1 million shafts per month, and each shafts rejected costs the firm 1p, find the monthly cost of rejects.

[8 Marks]

(c)

A more accurate machine is available, which costs an additional £60 per month to purchase. If this machine is known to operate with a standard deviation of 0.016 mm, determine which machine should be purchased?

[8 Marks]

(d)

Assuming the company has purchased the second machine and it is set exactly as the first one (at 5.00 mm), estimate the process capability. Is the process well centred? Prove it.

[8 Marks]

3.

You have been recently employed as a Quality Engineer in a new prosperous company from the ship building industry. The top management of the company has been contemplating application for ISO9000 registration. However, within the company there are some controversial opinions about this and they have been delaying the application.

(a)

You have been invited to express your opinion at a management meeting. Explain the benefits of having an approved/certified Quality Management System (QMS).

[11 Mark]

2.

(a)

What are the main Control Chart types and their relevant subtypes? Explain the use, their advantages and disadvantages.

[10 Marks]

(b)

Why is working with samples better than a single measurement/observations? Give an example.

[11 Marks]

(c)

Table Q2 shows data on the number of defects in computer motherboards. Study the process using a c control chart. Is the production process in control?

motherboard

Sample number

1

2

3

4

5

6

7

8

9

10

No of defects

7

5

3

4

3

8

2

3

4

3

Table Q2

[12 Marks]

Page 2 of 5

2018-19

(b)

The decision has been taken. Your next task is to prepare the company for ISO9000 registration. Describe the main stages and the relevant activities/events along the way to getting ISO9000 registration.

[12 Marks]

(c)

Working in the environment of a company applying for ISO9000 registration, explain all relationships between: QMS, Quality Objectives, Quality Policy and Top Management.

[10 Marks]

Page 3 of 5

2018-19

Some Important Formulae





 0

0

x

z

CL = c ,

UCL = c  3 c , LCL = c  3 c ).

2019-20