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CHAPTER 8
PURCHASING ANALYSIS TOOLS AND TECHNIQUES
8.4.4 TYPES OF PROCESS MAPS
There are two main types of process maps: linear process maps and cross-
functional process maps. Both types are used to describe how work gets done
though the cross-functional map also shows who (which functions) is involved
in getting it done.
A linear process map is a type of flow chart. Basic flowcharting conventions
apply using symbols: a box, an ellipse, a diamond, a square and an arrow. A
terminator or ellipse symbol shows the start and stop points in a process. When
used as a start symbol, terminators depict a trigger action that sets the process
flow in motion. A box is used to indicate a single accomplishment (or step) in a
process. The box is labelled, using the past tense form of the verb to describe the
accomplishment. Each box is assigned a reference number for easy identification
when discussing the process. A diamond is used to indicate that a decision is
made within the process. Usually, these are yes/no (binary) decisions that divide
the continuing process flow into two separate paths in response to the question
inside the diamond. A connector symbol or circle is typically small and is used
as a connector to show a jump from one point in the process flow to another.
A directional arrow is used to connect each box (or diamond) to the box that
precedes it and the box that follows it in the process. The arrow indicates the
input/output that is moving to/from each box (or diamond). Such input/output
can consist of material or information. The arrow shows not only what is moving
in the process but also the direction of movement. Table 8.1 shows the various
symbols used in linear process mapping.
Table 8.1:
Symbols used in linear process mapping.
Symbol
Description
Terminator symbol shows the start and stop points in a
process. When used as a start symbol, terminators depict
a trigger action that sets the process flow in motion.
Decision symbol. Indicates a question or branch in the
process flow. Typically, a decision flow chart shape is used
when there are two options (Yes/No, No/No-Go, etc.).
Connector symbol. In flow charts, this symbol is typically
small and is used as a connector to show a jump from
one point in the process flow to another.
Process symbols show a process or action step. This
is the most common symbol in both process flowcharts
and process maps.
Flow line connectors show the direction in which the
process flows.