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Question: Hart Manufacturing operates an automated steel fab...

Hart Manufacturing operates an automated steel fabrication process. For one operation, Hart has found that 45% of the total throughput (manufacturing cycle) time is spent on non-value-added activities. Delivery cycle time is 12 hours, waiting time during the production process is 3 hours, queue time prior to starting the production process is 2 hours, and inspection time is 1.2 hours.

a.What is the throughput (manufacturing cycle) time for the operation?

b.What is the move time recorded for the operation?

Solution

Delivery cycle time = Wait time + Throughput time
12 hours = 3 hours + Throughput time
Throughput time = 12 hours - 3 hours = 9 hours

Percentage of time spent on non-value-added activities = 100% - MCE
45% = 100% - MCE
MCE = 100% - 45% = 55%

MCE = Value-added time (Process time) ¸ Throughput (manufacturing cycle) time
55% = Process time ¸ 9 hours
Process time = 9 hours ´ 55% = 4.95 hours

Throughput time = Process time + Inspection time + Move time + Queue time
9.00 hours = 4.95 hours + 1.20 hours + Move time + 2.00 hours
Move time = 9.00 hours - (4.95 hours + 1.20 hours + 2.00 hours)
= 9.00 hours - 8.15 hours = 0.85 hours