Question

A production process at Kenneth Day Manufacturing is shown in the figure below. The drilling operation occurs separately from, and simultaneously with the sawing and sanding, which are independent sequential operations. A product needs to go through only one of the three assembly operations (the operations are in parallel). Q 2.5 units.hr 1.8 units/hr Assembly a Sawing 0.8 units/hr Sanding Welding 5 units/hr Assembly 0.8 units/hr Driling 5 units.hr Assembly 0.8 units/hr a) Sanding is the bottleneck b) The bottleneck time is minutes per unit (round your response to two decimal places).

Answer 1

a.

For the bottleneck we need to figure out the process giving least units per hour

Since assembly has three parts running in parallel, total capacity of assembly is 0.8*3 = 2.4 units per hour

Hence out of all processes, sanding has the least units/hr i.e 1.8 and hence is the bottleneck process

b. 1.8 units per hour implies 60 mins for 1.8 units i.e. 60/1.8 = 33.33 mins per unit

c.

For sawing it is 60/2.5	24	mins per unit
For drilling it is 60/5	12	mins per unit
For welding it is 60/5	12	mins per unit
For assembly it is 60/0.8	75	mins per unit

Hence throughput time will be total time taken for sawing + sanding + welding + assembly (since drilling takes less time compared to sawing + sanding) = 24 + 33.33 + 12 + 75 = 144.33 mins

d. 8 hrs per day 20 days a month i.e. 160 hrs i.e. 160X60 = 9600 mins

Monthly capacity of the manufacturing process = =9600/144.33 = 67