hal case study
HAL, Inc. is a major manufacturer of computers and computer components. In one of their plants they made printed circuit boards (PCB’s), which were used by other plants in the company in a variety of computer products.
The basic process runs 3 shifts per day and it can be briefly depicted by following flow diagram
The targeted output for the plant is 3000 boards per day, five days a week, with plant running three shifts per day. But the plant has been failed to reach and maintain the targeted throughput at a steady rate due to manufacturing complexities associated with the product mix. It was also found that, the output of the pro-coat process is very slow (1200 boards/day) compared to the expected throughput and therefore Hal has to engage a vendor on the pro- coat process to fulfil the demand. This engagement of vendor has caused increase in cost per board and two days delay because of shipping up and back. So the Hal is striving to increase the throughput of the pro-coat process and the purpose of this case study is to provide some guidance to them in their effort by giving some recommendations to improve the existing system.
Daily demand = 3000 boards
Working hours = 24- (Breaks + Lunch + shift change + Meeting) = 24-(20X2X3+40X3+10X3+90/5) = 19.2 hrs
Demand = 3000/(19.2X60) = 2.604 boards/min
Assumption;
1. Demand = Arrival rate ()
2. Arrival pattern exponentially distributed ()
Machine Name
Mean process (load) time (min)
Std. Dev. Process Time (min)
Trip Time (conveyor) (min)
MTBF (hr)
MTTR (hr)
Setup time (min)
Availability
Number of machines
Rate per day
Clean
0.33
0
15
80
4
0
0.95238
1
3325
Coat 1
0.33
0
15
80
4
0
0.95238
1
3325
Coat 2
0.33
0
15
80
4
0
0.95238
1
3325
Expose
103
67
0
300
10
15
0.96774
5
2834
Develop
0.33
0
2.67
300
3
0
0.99010
1
3456
Inspect
0.5
0.5
0
0
0
0
1.00000
2
The basic process runs 3 shifts per day and it can be briefly depicted by following flow diagram
The targeted output for the plant is 3000 boards per day, five days a week, with plant running three shifts per day. But the plant has been failed to reach and maintain the targeted throughput at a steady rate due to manufacturing complexities associated with the product mix. It was also found that, the output of the pro-coat process is very slow (1200 boards/day) compared to the expected throughput and therefore Hal has to engage a vendor on the pro- coat process to fulfil the demand. This engagement of vendor has caused increase in cost per board and two days delay because of shipping up and back. So the Hal is striving to increase the throughput of the pro-coat process and the purpose of this case study is to provide some guidance to them in their effort by giving some recommendations to improve the existing system.
Daily demand = 3000 boards
Working hours = 24- (Breaks + Lunch + shift change + Meeting) = 24-(20X2X3+40X3+10X3+90/5) = 19.2 hrs
Demand = 3000/(19.2X60) = 2.604 boards/min
Assumption;
1. Demand = Arrival rate ()
2. Arrival pattern exponentially distributed ()
Machine Name
Mean process (load) time (min)
Std. Dev. Process Time (min)
Trip Time (conveyor) (min)
MTBF (hr)
MTTR (hr)
Setup time (min)
Availability
Number of machines
Rate per day
Clean
0.33
0
15
80
4
0
0.95238
1
3325
Coat 1
0.33
0
15
80
4
0
0.95238
1
3325
Coat 2
0.33
0
15
80
4
0
0.95238
1
3325
Expose
103
67
0
300
10
15
0.96774
5
2834
Develop
0.33
0
2.67
300
3
0
0.99010
1
3456
Inspect
0.5
0.5
0
0
0
0
1.00000
2