CHAPTER 4: FLOW TIME ANALYSIS
4.1 Objective
Chapter 3 introduced the three basic building blocks of process flow namely the (average) flow time,
4.2 Additional Suggested Readings
We assign Pizza Pazza (Kellogg case) as the major case for this module. (The Kristen Cookie Company,
(HBR case #9-686-093) is a fine alternative; see problem 2 at end of chapter). The case is simple and
4.3 Solutions to the Problem Set
Solutions to Chapter 4:
4.1
a. The first step is to find the average flow time for “time with judge” and “pay fine”. This
can be done by averaging the ten observations given in the table. These amount to 1.55minutes
c. The flow time efficiency is 3.95/120 = 3.3%
4.2
a. The flow time of the two paths:
4.3.
a.
b. The critical path involves the food preparation. The flow time is 4+18 + 12 = 34 minutes
The flow time is 34 + 4 = 38 minutes
4.4
a.
b. The flow time is 50 minutes. The critical path is the one of F1 (process and separate,
Activity A, Activity B, Loan Officer).
4.5
a.
Activity
F1
Process
And
Loan
Officer
Activity
B
Activity
A
15
min
10
min
b. The critical path is the one through the X-ray scanner.