PROGRAM : BACHELOR OF ENGINEERING TECHNOLOGY
ENGINEERING: INDUSTRIAL
SUBJECT : FACILITY LAYOUT DESIGN and
MATERIALS HANDLING 2B
CODE : FACMIB2
TEST : ONE (1)
DATE : 28 August 2023
DURATION : 10:30 – 12:30
TOTAL MARKS : 75
ASSESSOR : Ms. B.N. MUSHWANA
MODERATOR : Dr R.P. MUTYAVAVIRE
NUMBER OF PAGES : 4 PAGES
INSTRUCTIONS : PLEASE ANSWER ALL QUESTIONS
ROUND OFF ALL ANSWERS TO 3 DECIMAL PLACES
1
QUESTION ONE
1.1 Manufacturing facilities frequently undergo layout design changes. Briefly discuss the
factors that may necessitate such changes. (6)
1.2 Mayibuye electronics has an annual demand of 9 000 circuit boards. The company
operates a double shift, 6 days per week, 4 weeks per month. The employees are afforded
45 minutes personal time per shift. The plant efficiency is 90%. The factory process
constitutes 5 main stations whose defectives rates are 4%, 3%, 0.5%, 1% and 0.8%
respectively. Determine the takt time.
(6)
[12]
QUESTION TWO
2.1 A stationery manufacturing company constitutes three workstations (A, B and C).
Inspection is performed at each station. In order to recover defective stationery products,
rework stations D, E and F are set up after each workstation. The scrap rates for stations
A, B, C, D, E & F are as follows: d A =4 %, d B=7 % , d C =3 % , d D=50 % , d E=45 % and
d F=65 %.
2.1.1 Determine the number of units that the process must start with in order to meet the
required output of 75 000 units (12)
2.1.2 How many defective units are produced at workstations B, D and F? (6)
2.1.3 Given that the scrap costs for processes A, B and C are R90, R75 and R120
respectively, calculate the scrap cost at processes A, B and C. (5)
[23]
2
QUESTION THREE
3.1 Briefly describe the three questions that must be answered before determining how many
machines are required.
(3)
3.2 A part requires four processing steps on three machines in the sequence A-B-C-B. The
demand for this part is 12 000 units per year. The company operates six days per week.
Given the performance data on Table Q3, determine the number of each machine
needed to meet the demand.
(15)
Table Q3: Performance data
Operation Machine Standard Time Efficiency Reliability Defects
1 A 3 min 93% 95% 3%
2 B 5 min 90% 92% 5%
3 C 4 min 85% 98% 2%
4 B 3 min 88% 90% 6%
[18]
QUESTION FOUR
4.1 Briefly discuss any four benefits of assembly line balancing. (4)
4.2 The demand for cell phones in a cell phone production company in Doornfontein is 2600
units per 12-hour shift. The production line efficiency is 88% and employee personal
time is 2 hours per shift. The individual workstation cycle times are given in Table Q4
below.
Table Q4: Workstation cycle times
Workstation Number Cycle Times (minutes)
001 0.744
003 0.521
005 0.705
007 0.438
009 1.000
011 0.382
4.2.1 Identify the bottleneck station, balance the assembly line and calculation the line
efficiency. (10)
4.2.2 After your initial balancing in question 4.2.1 above, identify the new bottleneck
station, re-balance the assembly line, determine the level and line efficiency and
interpret your answer. (8)
[22]
3
TOTAL MARKS: 75
Formulas
qo
q=
(1−d 1) ( 1−d 2 ) ( 1−d 3 ) …
operating time
Takt time =
total requirements
Defectives @ machine 1 = qd1
std time
Number of machines =
takt time
Conveyor speed = Hooks per min x Hook spacing
total std time
Line efficiency =
total average time
