Question

13. manufacturing is interested is in using the data Collected Stream mapping to Curosent state perstormance of its manual under UUUUUUU Anguilla interested dusing value evaluate the of the Capacity assembly line process different butch Size assumptions. The cuandbility of processing pero shift, after accounting for breaks and a midshift employee meeling is L36 mimutesThe current Opexeting Characterstics of each processing Step Com, only process one pest cat a time and all steps the must process Same Sized betches. 20 Cycle time Per part Setup time 3 I per batch I Saw Sand Drill Assemble 30 25 seconds Seconds Seconds Seconds minuley 4 To minutes minules minuts Morok 10 Seconds 8 minutes mindel 3 a). Calculate the queruge processing time per unit and the Capacity at each Step assuming butch sizes of is lo units i) 30 Units ii) 20 units iv) 40 units

Answer 1

Solution:

It is given that-

Availability of processing per shift = 436 minutes

1. Average processing time per unit:

Average processing time per unit = Cycle Time (sec) + ( Setup time (min) * 60 / Batch size)

Using this formula Average processing time is calculated as follows:

Process	Cycle Time per part (seconds)	Set-up Time per batch (minutes)	Processing Time per unit (Seconds per unit)
			10	20	30	40
Saw	20	3	38	29	26	24.5
Sand	15	4	39	27	23	21
Drill	30	0	30	30	30	30
Assemble	25	3	43	34	31	29.5
Mark	10	8	58	34	26	22

2. Bottleneck operations and Line’s processing capacity:

Bottleneck operation is the one with highest processing time for each batch size option. Bottleneck operations are highlighted in red and listed against the batch sizes as below:

Process	Cycle Time per part (seconds)	Set-up Time per batch (minutes)	Processing Time per unit (Seconds per unit)
			10	20	30	40
Saw	20	3	38	29	26	24.5
Sand	15	4	39	27	23	21
Drill	30	0	30	30	30	30
Assemble	25	3	43	34	31	29.5
Mark	10	8	58	34	26	22
Bottleneck			Mark	Assemble	Assemble	Drill
Line's processing capacity (Units per shift)			451.03	769.41	843.87	872.00

Also, the Line’s processing capacity is calculated by dividing available seconds per shift (436*60) by processing time per unit of the bottleneck operation. i.e. The Line capacity for batch size 30 is = (436*60)/31, and so on.

3. Batch sizes beyond 40 units will not increase the line’s capacity further.

Higher batch sizes distribute loss in set-up time, hence reduce the processing time per unit. For batch size 40, the bottleneck operation is “Drill” with a cycle time per unit of 30 seconds. This is already the operation with maximum cycle time among all. Batch sizes higher than 40 will reduce the processing times of other operations further, and hence bottleneck operation is not going to change. So, we can conclude that Drill is going to determine the line’s capacity and because its set up time is ZERO, its processing time will remain 30 seconds for all batch sizes.

So, beyond 40 units batch size, bottleneck operation and processing time are not changing, and the capacity will remain 872 units. For example, capacity is calculated below for batch size 50.

Process	Cycle Time per part (seconds)	Set-up Time per batch (minutes)	Processing Time per unit (Seconds per unit)
			10	20	30	40	50
Saw	20	3	38	29	26	24.5	23.6
Sand	15	4	39	27	23	21	19.8
Drill	30	0	30	30	30	30	30
Assemble	25	3	43	34	31	29.5	28.6
Mark	10	8	58	34	26	22	19.6
Bottleneck			Mark	Assemble	Assemble	Drill	Drill
Line's processing capacity (Units per shift)			451.03	769.41	843.87	872.00	872.00