23 Pressure equipment symbols

Pressure equipment symbols are in regular use in schematic drawings and Process and Instrumentation Diagrams (PIDs). There are many variations based on BS, ISO, and American standards. Figures 2.1-2.4 show some commonly used types. Table 2.3 and Figs 2.5 and 2.6 show symbols for typical pressure equipment-related instrumentation.

Visio Autoclave

Fig. 2.1 Vessel symbols. (Courtesy MS Visio)

Covered tank Gas holder Storage sphere Gas cylinder Horizontal vessel Autoclave

Fig. 2.1 Vessel symbols. (Courtesy MS Visio)

Vertical Heat Exchanger Visio

Fig. 2.2 Heat exchanger symbols. (Courtesy MS Visio)

"a

Fig. 2.2 Heat exchanger symbols. (Courtesy MS Visio)

Visio Heat Exchanger

Fig. 2.3 Valves and fittings. (Courtesy MS Visio)

Fig. 2.3 Valves and fittings. (Courtesy MS Visio)

Isa Ball Valve Symbol

Fig. 2.4 Piping and fittings symbols. (Courtesy MS Visio)

"a

Fig. 2.4 Piping and fittings symbols. (Courtesy MS Visio)

Self contained

Pressure reducing

External regulator tap

Back pressure regulator

Differential pressure reducing regulator -shown with internal and external pressure taps

Self-actuated regulators

Self-actuated regulators

Isa Ball Valve Symbol
Relief valves

With well

Temperature regulator filled system

Level regulator, float operated -mechanical linkage

p"ank

Traps

Continuous With drainer ball equalizing float type connection

Temperature and level regulators

Fig. 2.5 Valve/regulator symbols from ISA S5.1

Type Flow Meter Isa Symbol
Fig. 2.6 Flow measurement symbols from ISA S5.1

Table 2.3 Typical instrument identification letters

First letters Succeeding letters

Measurement Modifier Readout or Output function Modifier passive function

First letters Succeeding letters

Measurement Modifier Readout or Output function Modifier passive function

Table 2.3 Typical instrument identification letters

A =

Analysis

Alarm

B =

Burner, combustion

User's choice

User's choice

User's choice

C =

Conductivity (electrical)

Control

D =

Density or Sp. Gr

Differential

E =

Voltage (Emf)

Sensor (primary element)

F =

Flow rate

Ratio (fraction)

G =

User's choice

Glass or viewing device

H =

Hand (manual)

High

I =

Current (electrical)

Indicate

J =

Power

Scan

K =

Time or time schedule

Time rate of change

Control station

L =

Level

Light

Low

M =

User's choice

Momentary

Middle or intermediate

N =

User's choice

User's choice

User's choice

User's choice

O =

User's choice

Office (restriction)

P =

Pressure or vacuum

Test or sample point

Q =

Quantity

Integrate or totalize

R =

Radiation

Record or print

S =

Speed or frequency

Safety

Switch

T =

Temperature

Transmit

U =

Multi-variable

Multi-function

Multi-function

Multi-function

V =

Vibration. mech. analysis

Damper or louvre

W =

Weight or force

Well

X =

Unclassified

X axis

Unclassified

Unclassified

Unclassified

Y =

Event state or presence

Y axis

Relay. Compute. Convert

Z =

Position or dimension

Z axis

Drive. Actuator. Etc.

+3 0

Post a comment