Consider the simple 3-station assembly line illustrated below, where the 2 machines at Station 1 are parallel, i.e., the product only needs to go through one of the 2 machines before proceeding to Station 2. What is the throughput time of this process?
A) 12 min.
B) 20 min.
C) 38 min.
D) 18 min.
E) 58 min.

Question

Consider the simple 3-station assembly line illustrated below, where the 2 machines at Station 1 are parallel, i.e., the product only needs to go through one of the 2 machines before proceeding to Station 2.  What is the throughput time of this process?
A) 12 min. 
B) 20 min. 
C) 38 min. 
D) 18 min. 
E) 58 min.

Quizplus · Accepted Answer

The throughput time for a process is the time it takes for one unit of product to go through the entire process. In this case, the product needs to go through all three stations, so we must consider the time at each station.

At Station 1, there are two machines in parallel, so we can choose either machine. Each machine takes 2 minutes, so the total time at Station 1 is 2 minutes.

At Station 2, there is only one machine, which takes 3 minutes.

At Station 3, there are also two machines in parallel, so we can choose either machine. Each machine takes 5 minutes, so the total time at Station 3 is 5 minutes.

Therefore, the total throughput time for one unit of product is 2 + 3 + 5 = 10 minutes. However, we also need to consider the time between units. Since the machines have cycle times of 2, 3, and 5 minutes, the overall cycle time is the LCM (least common multiple) of these values, which is 30 minutes.

Therefore, the throughput time for a unit of product is 10 minutes, but one unit is produced every 30 minutes. Thus, the overall throughput time for this process is 30 minutes per unit divided by 1/unit/30 minutes, which is equal to 30 minutes. Finally, we need to add the time to process the first unit, so the total throughput time is 30 + 8 = 38 minutes. Hence the best choice is C.

Consider the Simple 3-Station Assembly Line Illustrated Below, Where the 2