Assembly Line Balancing:
PROJECT-Spring 2016
La-Z-Man Furniture is competing in a high-tech market by launching a living room product that has presumably a steady demand in next few years. The product is simple but one of its sub-assembly systems, called Base-plate combo, needs the following 11 assembly operations to be completed before it is sent to the main assembly line. The precedence constraints and the processing times (in minutes) of these assembly operations are shown in Figure 1. The demand of the base-plate combo is forecasted as 40, 25, 30, 35, and 30 units each working day of a 5-day week. The furniture factory works on an 8-hour single shift per day schedule.
Figure 1. Precedence diagram and operation times
Currently the company is facing various problems of manpower imbalance, component stock-outs, excess inventory and other associated coordination problems. Most of the time the manager cannot meet the weekly demand for this inefficient planning and management. As a small businessman, the manager/owner sought your expertise help in using your IE knowledge to solve this problem.
Earlier the manager used to produce about 25 items a day on the average. The manager heard that by implementing an assembly line balancing technique he could improve its productivity and balance the manpower. How will you advise and plan for him to design a well-balanced assembly line? What is your effective production rate? What is the expected efficiency of the line? Show your proposed line configuration as well.
B. Material Requirement Planning
Some of the assembly operations require components that have to be ordered from outside and the number of sub-assembly components (W, X, Y and Z) needed for the different 11 assembly operations is given in Table 1. Acceptable ordering practices (fixed, variable or lot-for-lot) and leadtimes for the sub-assembly components are shown in the Table 1 and the MRP tree for the sub-assembly components (W, X, Y, and Z) is given in Figure 2.
How would you recommend the planned order release (POR) and bill of materials (BOM) for all components for a week? Draw the feeder lines and show the arrangement of feeding components for assembly.
Table 1. Feeding components needed for assembly operations
|
Sub-assembly Component
|
Ordering practice
|
Leadtime (day)
|
Number of sub-assembly components needed for assembly operations
|
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
|
W
|
LFT
|
1
|
-
|
-
|
1
|
-
|
-
|
-
|
1
|
-
|
2
|
-
|
-
|
|
X
|
LFT
|
3
|
2
|
-
|
-
|
-
|
-
|
1
|
-
|
-
|
2
|
-
|
-
|
|
Y
|
F=100
|
3
|
-
|
1
|
-
|
-
|
2
|
-
|
-
|
3
|
-
|
1
|
-
|
|
Z
|
V=150
|
1
|
-
|
1
|
-
|
-
|
1
|
-
|
-
|
-
|
1
|
-
|
-
|
Figure 2. MRP Tree for feeding components
C. Optimal ordering policy:
The simple BOM procedure does not consider the economic perspectives of the operation. In reality, placing an order costs money and manpower. On the other hand, holding the inventory also incurs warehouse/carrying cost. How would you give an economic plan for BOM for the company such that the total cost of ordering and carrying is minimized? Assume any reasonable data you need.
REPORT/RESEARCH PAPER:
The project must contain at least the following ingredients:
- Cover page: Title of the project, your name(s), course number and date of submission.
- Abstract page
- Introduction
- Description of the system or material flow
- Goal and objective of study
- Solution methodology
- Results
- Discussion and conclusion
- Recommendation
- References, and
- Appendices (if any).
You may use any kind of figure or picture to explain the proposal better. You can email me it.