Question

Old City Photographics (OCP) specializes in processing traditional 35 mm film negatives. OCP offers three packages to its customers. With the standard package, the customer gets a set of 6”x4” prints. The deluxe package adds to the standard package a CD-ROM of high resolution scans of the pictures. Finally, the pro package is similar to the deluxe package in that it comes

with a CD-ROM, except that the customer gets a contact print rather than a set of prints. On average, OCP receives 15 jobs per hour consisting of 50 percent standard, 30 percent deluxe, and 20 percent pro. All jobs require 2 min per unit to process the film at the processing station. Making the 6”x4”

prints takes 4 min per unit at the print station. Scanning the film on to a CD-ROM takes 5 min per unit at the scanning station. Making the contact print takes 10 min per unit at the contact print station.

a.   How many jobs will arrive per hour at each station?

b.   Determine the bottleneck and flow rate.

Answer 1

a) Following numbe of jobs arrive per hour at each station

Process film = s+p+d = 15 jobs per hour

Scan film = d+p = 15*.3+15*.2 = 7.5 jobs per hour

Make 6x4 prints = s+d = 15*0.5+15*0.3 = 12 jobs per hour

Make contact print = p = 15*0.2 = 3 jobs per hour

b) Utilization of station Process film = Throughput / Capacity = 15 jobs per hour / (60/2) = 0.5

Utilization of station Scan film = Throughput / Capacity = 7.5 jobs per hour / (60/5) = 0.63

Utilization of station Make 6x4 print = Throughput / Capacity = 12 jobs per hour / (60/4) = 0.80

Utilization of station Make contact print = Throughput / Capacity = 3 jobs per hour / (60/10) = 0.50

The maximum utilization is of Make 6x4 print station. Therefore, it is the bottleneck.

Flow rate is 15 jobs per hour