Homework 3 Group Technology Design and Operational Scheduling

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Homework 3Group Technology Design and
Operational Scheduling

• Due on November 22, 2006
• Maximum group size is 2 students

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Question 1

• Assume that a machining operation produces 20
  products with a machine and routing operation
  shown in Figure 1.
• Consider the following production requirements
  for the 20 different part numbers given in Table
  1. Develop a machine grouping plan to build the
  products in part families.
• Illustrate the new layout and routing for the
  facility accounting for all machines.

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Figure 1 - Production Flow
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Table 1. Production Operations
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
L X X X X x x x x x x x x x x x
M1 x x x x x x x x x x X x
M2 x x X x x x x x x x x
D x x x x x x x x x x x x x x
G x x x x x x x x x x x
L Lathe M1 Machine Type 1 M2 Machine Type 2
D Drilling Machine G Grinding Machine
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Question 2

• Next assume that production for each part in one
  group did not have the same processing routing
  sequence. The routing sequence for a series of
  parts is noted in the following Table 2.
• 2.A) For this operation, a loop operation using
  the diagram as shown in Figure 2 is proposed.
  Arrange the lathes, machine, drill, and grinder
  to minimize the flow for the loop conveyor.
• 2.B) If you are allowed to buy one more machine
  (i.e. machine duplication), which machine would
  you like to buy and why? What will be the new
  layout?

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Table 2. Product Sequence for One Group
Product Volume Sequence
A 800 L-D-G
B 1200 L-M1-G-M2
C 3700 D-L-M1-G
D 1500 D-M1-L-G
E 900 D-M1-G-L-G
F 2200 M1-G-L-D
G 1400 D-M1-L-M1-G
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Figure 2 Loop Layout
Material Flow
Lathe
Grind
Machine 1
Drill
Machine 2
Lathe
Grind
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Question 3

• Assume that the following Table 3 provides a
  series of parts to be produced in the proposed
  cell. The dates show the required due date for
  production and the cost shows the tardiness cost
  per unit per week for each product. Develop a
  production schedule to produce the products while
  minimizing the total tardiness cost.
• Assume that the available production time is 40
  hours per week (or 8 hours per day) on each
  machine. The number of machines for each type are
  2 Lathes,1 Drill, 2 Grinders, 1 M1 and1 M2.
• Products A, B and C belong to Family 1, and
  Products D, E, F and G belong to Family 2. If you
  switch from one family to another one on any
  machine, the required setup time is 4 hours.
  There is no setup time for the products within
  the same family.

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Table 3. Operational Data
Product Volume Sequence Time (min) Cost/Unit Due Date
A 800 L-D-G 2-3-1 150 Week 1
B 1200 L-M1-G-M2 3-1-4-4 100 Week 2
C 3700 D-L-M1-G 1-1-2-5 200 Week 3
D 1500 D-M1-L-G 2-2-3-1 400 Week 4
E 900 D-M1-G-L-G 1-2-2-1-5 200 Week 4
F 2200 M1-G-L-D 1-2-3-2 400 Week 5
G 1400 D-M1-L-M1-G 1-1-2-1-4 200 Week 5