---
title: "STANDARD DRAFTING SYMBOLS CHART — asset register"
doc_type: pid-asset-register
drawing_number: "4003-00001-01"
revision: "1"
source: "TS-112-Process-and-Instrument-Diagrams.pdf (page 16 of 27)"
tags: [line-main, line-secondary, line-covered, line-open, line-instrument, line-undefined, line-pneumatic, line-electrical, line-electrical-digital, line-software, term-point, in-left-out-right, out-left-in-right, flow-arrow, conn-lines, val-globe-diaph-sus, val-globe-diaph-reg, val-globe-diaph-relief, val-spring-act-relief, val-spring-act-90-relief]
summary: "This document is a legend drawing that defines standard symbology for process and instrumentation diagrams used by SA Water. It provides descriptions for line types, valves, fittings, sensors, flow elements, and hazardous classification levels."
---

# STANDARD DRAFTING SYMBOLS CHART

This document is a legend drawing that defines standard symbology for process and instrumentation diagrams used by SA Water. It provides descriptions for line types, valves, fittings, sensors, flow elements, and hazardous classification levels.

**Source:** TS-112-Process-and-Instrument-Diagrams.pdf · page 16/27 · **Drawing:** 4003-00001-01 rev 1 · **Components:** 87 (1 equipment, 15 instrument, 25 valve, 10 line, 36 other)

## Equipment (1)

| Tag | Description | Details | Connects to |
|---|---|---|---|
| pump-var-speed | PUMP DRIVEN BY A VARIABLE SPEED MOTOR | SIC in circle, M in circle, Pump symbol | — |

## Instruments (15)

| Tag | Function (ISA 5.1) | Description | Details | Connects to |
|---|---|---|---|---|
| lvl-ultrasonic | LE = Level Element | ULTRASONIC | Circle with tag | — |
| lvl-cond-probe | LE = Level Element | CONDUCTIVITY PROBE | Circle with tag | — |
| lvl-ball-float | LE = Level Element | BALL FLOAT | Circle with tag | — |
| flow-orifice | — | FLOW ELEMENT, ORIFICE TYPE | Lines on pipe | — |
| flow-flume | — | FLUME | Venturi-like shape | — |
| flow-element-balloon | FE = Flow Element | FLOW ELEMENT CODE BALLOON | Circle tag on line | — |
| flow-mag | — | MAGNETIC FLOWMETER | Box with 'M' | — |
| flow-pitot | — | PITOT TUBE or ANNUBAR | Box with J-tube | — |
| flow-pos-disp | — | POSITIVE DISPLACEMENT FLOWMETER | Box with figure-8 | — |
| flow-therm-mass | — | THERMAL MASS FLOWMETER | Box with 'T' | — |
| flow-turbine | — | TURBINE FLOWMETER | Box with 'X' | — |
| flow-ultrasonic | — | ULTRASONIC FLOWMETER | Box with 'U' wave | — |
| flow-var-area | — | VARIABLE AREA FLOW INDICATOR | Circle overlapping triangle | — |
| flow-vortex | — | VORTEX METER | Box with triangle | — |
| flow-weir | — | WEIR | V-notch symbol | — |

## Valves (25)

| Tag | Description | Details | Connects to |
|---|---|---|---|
| val-globe-diaph-sus | GLOBE, DIAPHRAGM TYPE PRESSURE SUSTAINING VALVE | PSV tag in circle | — |
| val-globe-diaph-reg | GLOBE, DIAPHRAGM TYPE PRESSURE REGULATING VALVE | PCV tag in circle | — |
| val-globe-diaph-relief | GLOBE, DIAPHRAGM TYPE PRESSURE RELIEF VALVE | PRV tag in circle | — |
| val-spring-act-relief | SPRING ACTUATEDPRESSURE RELIEF VALVE | PSV tag in circle | — |
| val-spring-act-90-relief | SPRING ACTUATED 90 DEG PRESSURE RELIEF VALVE | PSV tag in circle | — |
| val-hocv | HOCV | Pressure setting ...kPa | — |
| val-hosv | HOSV | Pressure setting ...kPa | — |
| val-angle | VALVE, ANGLE | Two triangles | — |
| val-ball | VALVE, BALL | Bowtie with circle | — |
| val-butterfly | VALVE, BUTTERFLY | Bowtie with angled dash | — |
| val-diaph | VALVE, DIAPHRAGM | Bowtie with mushroom | — |
| val-fire-plug | VALVE, FIRE PLUG | Simple bowtie | — |
| val-gas-release | VALVE, GAS RELEASE | Symbol with loop | — |
| val-gate | VALVE, GATE | Simple bowtie | — |
| val-general | VALVE, GENERAL | Simple bowtie | — |
| val-globe | VALVE, GLOBE | Bowtie with dot | — |
| hydrant | HYDRANT | Square with 'H' | — |
| val-knife-gate | VALVE, KNIFE GATE | Bowtie with vertical line | — |
| val-needle | VALVE, NEEDLE | Bowtie with angled arrow | — |
| val-non-return | VALVE, NON RETURN | N shape in bowtie | — |
| val-backflow-prev | VALVE, BACKFLOW PREVENTION DEVICE | Double Z shape in bowtie | — |
| penstock | PENSTOCK | Vertical rectangle | — |
| val-pinch | VALVE, PINCH | Crosses in bowtie | — |
| val-plug | VALVE, PLUG | Diamond in bowtie | — |
| val-3-way | VALVE, 3 WAY | Three triangles meeting | — |

## Lines (10)

| Tag | Description | Details | Connects to |
|---|---|---|---|
| line-main | MAIN PROCESS LINES | Thick solid line | — |
| line-secondary | SECONDARY PROCESS LINE | Thin solid line | — |
| line-covered | COVERED CHANNEL | Dashed thick line | — |
| line-open | OPEN CHANNEL | Parallel thin lines | — |
| line-instrument | INSTRUMENT SUPPLY OR CONNECTION TO PROCESS | Solid line with short perpendicular dashes | — |
| line-undefined | UNDEFINED SIGNAL | Line with cross dashes | — |
| line-pneumatic | PNEUMATIC SIGNAL | Line with double cross dashes | — |
| line-electrical | ELECTRICAL SIGNAL | Dashed line | — |
| line-electrical-digital | ELECTRICAL SIGNAL (DIGITAL) | Line with 'o' symbols | — |
| line-software | SOFTWARE LINK | Line with open circles | — |

## Other (36)

| Tag | Description | Details | Connects to |
|---|---|---|---|
| term-point | TERMINATION POINT | Arrowhead on line segment, existing vs new | — |
| in-left-out-right | IN LEFT/OUT RIGHT | Arrow box with label placeholders | — |
| out-left-in-right | OUT LEFT/IN RIGHT | Arrow box with label placeholders | — |
| flow-arrow | LIQUID FLOW ARROW | Solid arrowhead on line | — |
| conn-lines | CONNECTION (OF LINES) | Intersecting lines with dot | — |
| act-diaph | DIAPHRAGM | Mushroom shape | — |
| act-diaph-bal | DIAPHRAGM, PRESSURE BALANCED | Mushroom with line | — |
| act-float | FLOAT | Line with circle | — |
| act-hand | HAND ACTUATED OR HANDWHEEL | T shape | — |
| act-piston | PISTON | Rectangle on line | — |
| act-piston-pos | PISTON ACTUATOR WITH POSITIONER OR POSITION SWITCHES | Rectangle with small box | — |
| act-pos-shown | POSITIONER SHOWN ON ACTUATOR | Mushroom with side circle | — |
| act-pos-tag | POSITIONER TAG | Small square tag | — |
| act-rotary | ROTARY MOTOR (MAY BE ELECTRIC HYDRAULIC or PNEUMATIC) | Circle with 'M' | — |
| act-sol | SOLENOID | Square with 'S' | — |
| act-spring | SPRING - FOR PRESSURE RELIEF OR SAFETY VALVE ONLY | Zig-zag line | — |
| act-weight | WEIGHT | Rectangle with line | — |
| stop-plate | STOP PLATE | Line with crossbar | — |
| stoplog | STOPLOG | Stacked rectangles | — |
| fit-cap | CAP | Arc at line end | — |
| fit-blind-flange | BLIND FLANGE | Short vertical line on end | — |
| fit-flange-joint | FLANGE JOINT | Two short vertical lines | — |
| fit-flex-coupling | FLEXIBLE COUPLING | Curved lines joining | — |
| fit-flex-hose | FLEXIBLE HOSE | Wavy line | — |
| fit-hose-coupling | HOSE COUPLING | Rectangle connector | — |
| fit-nozzle | NOZZLE | Arrowhead | — |
| fit-red-con | REDUCER - CONCENTRIC | Trapezoid on axis | — |
| fit-red-flat-bot | REDUCER - FLAT BOTTOM | Trapezoid flat bottom | — |
| fit-red-flat-top | REDUCER - FLAT TOP | Trapezoid flat top | — |
| gen-plot-light | PLOT LIGHT | Circle with cross lines | — |
| gen-press-set-r | PRESSURE SETTING BALLOON (RIGHT) | Circle on line right | — |
| gen-press-set-l | PRESSURE SETTING BALLOON (LEFT) | Circle on line left | — |
| gen-undef-intl | UNDEFINED INTERLOCK LOGIC | Diamond symbol | — |
| haz-lvl-b | HAZ LEVEL (AVERAGE) eg. CHLORINE, CAUSTIC | Hexagon with 'B' | — |
| haz-lvl-e | HAZ LEVEL (LOW) eg. POLYMER, HIGH PRESSURE | Hexagon with 'E' | — |
| haz-lvl-f | HAZ LEVEL (NEGLIGIBLE) eg. WATER | Hexagon with 'F' | — |

## Notes on drawing

- THIS DRAWING SHOWS THE STANDARD SYMBOLS TO BE USED WHEN PRODUCING P&ID's FOR SA WATER AND ON ALL SA WATER PROJECTS. REFER TO TS112
- DO NOT SCALE PAPER PRINT