Angels Inc. is considering bringing the garage fabrication process (which is cur

ID: 326663 • Letter: A

Question

Angels Inc. is considering bringing the garage fabrication process (which is currently outsourced) in-house. If garage fabrication were brought in-house, the factory would be structured as follows. Roofs are punched in a roof punching press (10 minutes per roof) and then formed in a roof forming press (5 minutes per roof). Bases are punched in a base punching press (10 minutes per base) and then formed in a base forming press (15 minutes per base), and the formed base is welded in a base welding machine (5 minutes per base).

The base sub-assembly and the roof then go to final assembly where they are welded together (10 minutes per garage) on an assembly welding machine to complete the garage. Assume one operator at each station.

(a)What is the minimum time required to produce a garage (from starting an order to finishing it)?

(b)What is the capacity of the factory in terms of garages per hour?

(c)If you want to increase the capacity, what is the stage that you would put some additional resources?

Explanation / Answer

The precedence diagram of the garage fabrication process is as follows :

Punching of roof

Punching of base

Forming of roof

Forming of base

Welding of base

Welding of base subassembly and roof sub assembly

Throughput time required for roof preparation process

= time required for punching of roof + Time required for forming of roof

= 10 + 5

= 15 minutes

Throughput time required for base preparation process

= Time required for punching of base + Time for forming of base + Time for welding of base

= 10 + 15 + 5

= 30 minutes

Since above 2 processes are parallel and time required for base preparation process is more, effective throughput time of base and roof preparation process = 30 minutes

Time required for welding and roof subassembly = 5 minutes

Therefore , total throughput time of the full process = 30 minutes + 5 minutes = 35 minutes

The throughput time of the base preparation process should be < = 15 minutes ( i.e. same or less than equal to throughout time required for roof preparation process )

Therefore , additional resources may be put on Punching of base/ Forming of base / Welding of base