Table 9.23
The Terminal Company is attempting to balance its assembly line of high-voltage electrical connectors. The desired output for the line is 50 connectors per hour, and the information on the work elements for this assembly line is as follows.
$$\begin{array} { | c | c | c | }
\hline \begin{array} { c }
\text { Work } \
\text { Elements }
\end{array} & \begin{array} { c }
\text { Time } \
\text { (sec) }
\end{array} & \begin{array} { c }
\text { Immediate } \
\text { Predecessor(s) }
\end{array} \
\hline \mathrm { A } & 40 & - \cdot \
\mathrm { B } & 36 & \mathrm {~A} \
\mathrm { C } & 20 & \mathrm {~A} \
\mathrm { D } & 2 & \mathrm {~A} \
\mathrm { E } & 30 & \mathrm {~B} , \mathrm { C } \
\mathrm { F } & 34 & \mathrm { D } \
\mathrm { G } & 35 & \mathrm { E } \
\mathrm { H } & 5 & \mathrm {~F} \
\mathrm { I } & 15 & \mathrm { E } , \mathrm { H } \
\mathrm { J } & 40 & \mathrm { H } \
\mathrm { K } & 38 & \mathrm { G } , \mathrm { I } , \mathrm { J } \
\hline
\end{array}$$
-Use the information from Table 9.23,and the longest work-element rule to balance this line.If the time needed to perform work element K was reduced by 1 second and all other work element times were unchanged,what would happen to the number of stations needed to balance the line?
A) It would stay the same.
B) It would decrease by 1 station.
C) It would decrease by 2 stations.
D) It would increase by 1 station.

Question

Table 9.23
The Terminal Company is attempting to balance its assembly line of high-voltage electrical connectors. The desired output for the line is 50 connectors per hour, and the information on the work elements for this assembly line is as follows.
 $$\begin{array} { | c | c | c | } 
\hline \begin{array} { c } 
\text { Work } \
\text { Elements }
\end{array} & \begin{array} { c } 
\text { Time } \
\text { (sec) }
\end{array} & \begin{array} { c } 
\text { Immediate } \
\text { Predecessor(s) }
\end{array} \
\hline \mathrm { A } & 40 & - \cdot \
\mathrm { B } & 36 & \mathrm {~A} \
\mathrm { C } & 20 & \mathrm {~A} \
\mathrm { D } & 2 & \mathrm {~A} \
\mathrm { E } & 30 & \mathrm {~B} , \mathrm { C } \
\mathrm { F } & 34 & \mathrm { D } \
\mathrm { G } & 35 & \mathrm { E } \
\mathrm { H } & 5 & \mathrm {~F} \
\mathrm { I } & 15 & \mathrm { E } , \mathrm { H } \
\mathrm { J } & 40 & \mathrm { H } \
\mathrm { K } & 38 & \mathrm { G } , \mathrm { I } , \mathrm { J } \
\hline
\end{array}$$
-Use the information from Table 9.23,and the longest work-element rule to balance this line.If the time needed to perform work element K was reduced by 1 second and all other work element times were unchanged,what would happen to the number of stations needed to balance the line?
A) It would stay the same.
B) It would decrease by 1 station.
C) It would decrease by 2 stations.
D) It would increase by 1 station.

Quizplus · Accepted Answer

To balance the line, we will use the longest work element (LWE) rule.

1. Calculate the minimum number of stations required:

Let LWE = A = 40 seconds
Desired output = 50 connectors per hour = 0.833 connectors per minute

Minimum number of stations = (0.833 x 60 seconds) / 40 seconds = 1.25
Round up to the nearest integer: 2

2. Assign work elements to stations:

Station 1: A, B, C, D (total time = 40 + 36 + 20 + 2 = 98 seconds)
Station 2: E, F, G (total time = 30 + 34 + 35 = 99 seconds)
Station 3: H, I, J (total time = 5 + 15 + 40 = 60 seconds)
Station 4: K (total time = 38 seconds)

Cycle time = Longest station time = 99 seconds
Theoretical minimum = (sum of work element times) / cycle time = (40 + 36 + 20 + 2 + 30 + 34 + 35 + 5 + 15 + 40 + 38) / 99 = 4.91, round up to 5.
Actual output = (number of stations) / (theoretical minimum) = 2 / 5 = 0.4 connectors per minute = 24 connectors per hour.

3. If time needed to perform work element K was reduced by 1 second, the new time would be 37 seconds. The new total work element time for station 4 would be 37 seconds, and the total cycle time would be reduced by 1 second.

New cycle time = 98 + 99 + 60 + 37 = 294 seconds
New theoretical minimum = (sum of work element times) / cycle time = (40 + 36 + 20 + 2 + 30 + 34 + 35 + 5 + 15 + 40 + 37) / 294 = 4.89, round up to 5.
New actual output = (number of stations) / (theoretical minimum) = 2 / 5 = 0.4 connectors per minute = 24 connectors per hour.

Since the actual output remains the same, the number of stations needed to balance the line would also remain the same, so the answer is B.

Table 923 the Terminal Company Is Attempting to Balance Its Assembly

Table 923
the Terminal Company Is Attempting to Balance Its Assembly