DOE-HDBK-1016/1-93
ENGINEERING FLUIDS DIAGRAMS AND PRINTS
Engineering Fluid Diagrams and Prints
The diagram may also depict
Figure 8 More Piping Symbols
the
individual
fittings
comprising the piping runs
depending on its intended use.
Figure 8 shows symbols used
to depict pipe fittings.
Instrumentation
One of the main purposes of a
P&ID is to provide functional
information
about
how
instrumentation in a system or
piece of equipment interfaces
with the system or piece of
equipment. Because of this, a
large amount of the symbology
appearing on P&IDs depicts
instrumentation and instrument
loops.
The symbols used to represent
instruments and their loops can
be divided into four categories.
Generally each of these four
categories uses the component
identifying (labeling) scheme identified in Table 1. The first column of Table 1 lists the letters
used to identify the parameter being sensed or monitored by the loop or instrument. The second
column lists the letters used to indicate the type of indicator or controller. The third column lists
the letters used to indicate the type of component. The fourth column lists the letters used to
indicate the type of signals that are being modified by a modifier.
PR-02
Rev. 0
Page 8