Question

DataSpan, Inc., automated its plant at the start of the current year and installed a flexible manufacturing system. The company is also evaluating its suppliers and moving toward Lean Production. Many adjustment problems have been encountered, including problems relating to performance measurement. After much study, the company has decided to use the performance measures below, and it has gathered data relating to these measures for the first four months of operations.

Month 1 2 3 4 Throughput time (days)? ? ? ? Delivery cycle time (days)? ? ? ? Manufacturing cycle efficiency (MCE)? ? ? ? Percentage of on-time deliveries89%84%81%78%Total sales (units)3880 3714 3524 3390

Management has asked for your help in computing throughput time, delivery cycle time, and MCE. The following average times have been logged over the last four months:

  Average per Month (in days) 1234Move time per unit0.6 0.3 0.4 0.4 Process time per unit2.7 2.5 2.4 2.2 Wait time per order before start of production25.0 27.4 30.0 32.5 Queue time per unit4.4 4.9 5.5 6.2 Inspection time per unit0.7 0.9 0.9 0.7

Required:

1-a. Compute the throughput time for each month.

1-b. Compute the delivery cycle time for each month.

1-c. Compute the manufacturing cycle efficiency (MCE) for each month.

2. Evaluate the company's performance over the last four months.

3-a. Refer to the move time, process time, and so forth, given for month 4. Assume that in month 5 the move time, process time, and so forth, are the same as in month 4, except that through the use of Lean Production the company is able to completely eliminate the queue time during production. Compute the new throughput time and MCE.

3-b. Refer to the move time, process time, and so forth, given for month 4. Assume in month 6 that the move time, process time, and so forth, are again the same as in month 4, except that the company is able to completely eliminate both the queue time during production and the inspection time. Compute the new throughput time and MCE.

Answer 1

1. (a)

	1	2	3	4
Move time	0.6	0.3	0.4	0.4
Process time	2.7	2.5	2.4	2.2
Inspectiontime	0.7	0.9	0.9	0.7
Queue time	4.4	4.9	5.5	6.2
Throughput time	8.4	8.6	9.2	9.5

(b)

	1	2	3	4
Throughput time	8.4	8.6	9.2	9.5
Wait time	25	27.4	30	32.5
Delievery cycle tim	33.4	36	39.2	42

(c) Manufacturing cycle efficiency = Process time/ Throughput time x 100

	1	2	3	4
Process time	2.7	2.5	2.4	2.2
Throughput time	8.4	8.6	9.2	9.5
MCE	32.14%	29.07%	26.09%	23.15%

2. Throughput time and delivery cylce time are increasing every month, so these are favorable trends and Manufacturing cycle efficiency is an unfavorable trend as it is decreasing every month.

3. (a)

Move time	0.4
Process time	2.2
Inspection time	0.7
Throughput time	3.3

MCE = 2.2/3.3 x 100 = 66.67%

(b)

Move time	0.4
Process time	2.2
Throughput time	2.6

MCE = 2.2/ 2.6 x100 = 84.61%