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P&ID Clarity Through Consistency

P&ID Symbology

P&ID symbology serves as the universal language of process engineering, depicting the assets and connections present on-site with clarity and precision. These symbols represent equipment, piping, valves, and inline components, often detailing their connection types—whether flanged, socket-welded, or threaded. With numerous standards available, choosing the right symbology is essential for maintaining consistency, readability, and compliance.

At Neonex Digital, we guide clients through the selection process, helping them adopt a standard that suits their operational and regulatory needs. Each P&ID typically includes a standards sheet, mapping symbols to their respective meanings, ensuring the diagrams remain an accessible and reliable reference for all stakeholders.
Consistency
Standardised P&IDs ensure engineers and stakeholders can interpret them quickly and accurately, reducing errors and improving efficiency. A consistent approach across a site or company creates a reliable reference for maintenance, projects, and safety. /

P&ID Standards

PIP
Process Industry Practices. /
BS 5070
British Standard for graphical symbols and diagrams. /
BS EN ISO 10628
European standard for diagrams for process industry. /
ASME B31.3
American standard for process piping. /
CUSTOM
Neonex Digital can guide clients in deciding whether to adopt a recognized standard or develop custom symbols tailored to their needs. /

Neonex Digital's expertise spans multiple industry standards, ensuring we can guide our customers in selecting and implementing the right standard for their site or company.

P&ID Symbols

Gate Valve (open)

Gate Valve (closed)

Ball Valve (open)

Ball Valve (closed)

Globe Valve (open)

Globe Valve (closed)

Butterfly Valve (open)

Butterfly Valve (closed)

Plug Valve (open)

Plug Valve (closed)

Needle Valve (open)

Needle Valve (closed)

Diaphragm Valve (open)

Diaphragm Valve (closed)

Valve with Orifice (open)

Valve with Orifice (closed)

Slide Gate Valve (open)

Slide Gate Valve (closed)

Knife Valve (open)

Knife Valve (closed)

Conduit Gate Valve (open)

Conduit Gate Valve (closed)

Pinch Valve (closed)

Pinch Valve (closed)

Integral Block and Bleed Valve (open)

Integral Block and Bleed Valve (closed)

Integral Double Block and Bleed Valve (open)

Integral Double Block and Bleed Valve (closed)

Self Draining Valve (open)

Self Draining Valve (closed)

Float Valve

Y Glove Valve

Y Blowdown Valve

Check Valve (NRV)

Angle Valve

Angle Globe Valve

Angle Blowdown Valve

Vacuum Breaker

Pressure Vacuum Valve

Safety (Relief) valve

Angle Check Valve

Angle Stop Check Valve

3 Way Gate Valve

3 Way Globe Valve

3 Way Ball Valve

3 Way Valve (Normal Position)

4 Way Valve

4 Way Valve (Normal Position)

4 Way Plug Valve

Deluge Valve

Deluge Valve

Multivane Valve

Control Valve

Control Valve (Internally Operated)

Control Valve (Externally Operated)

Motor Activated Valve

Electro-Hydraulic Valve

Solenoid Valve

3 Way Solenoid Valve

3 Way Control valve

Thermal Release Hydraulic Shut Valve

Hydraulic Valve

4 Way Solenoid Valve

1-Solenoid with Manual Reset

Diaphragm

Balanced Diaphragm

Piston Operator

Manual Handwheel

Spring

Reducer

Welded Cap

Screwed Cap

Flanges

Blind Flange

Hose Connection

Reducer Flange

Expansion Flange

Open Spectacle Blind

Closed Spectacle Blind

Open Spacer

Closed Spacer

Bursting Disc

Orifice Plate

Orifice Union

Union

Quick Change Orifice Plate

Plug

Open Drain

Closed Drain

Blind No.

Sample Connection Point

Sight Flow Glass

Basket Strainer

Duplex Strainer

T-Strainer

Y-Strainer

Temporary Strainer

Cone Strainer

Flat Plate Strainer

Sump Strainer

Filter

Steam Trap

Liquid Trap

Float Trap

Inverted Bucket Trap

Thermostatic Trap

Thermodynamic Trap

Impulse Trap

Flame Arrestor

Vent Silencer

In-Line Silencer

Exhaust

Swing Elbow

Expansion Joint

Flexible Hose

Variable Area Flow (Rotameter)

Positive Displacement

Propeller (Turbine Meter)

Venturi

Flow Nozzle

Vortex

Coriolis Mass Flow

Ultrasonic Flow Meter

Averaging Pitot (Annubar)

Target (Flow)

Diaphragm Seal

Ejector

Mixing Tee In-Line

Breather

Removable Spool

Hammer Arrestor

Current to Pneumatic (Converter)

Corrosion Probe

Static Mixer

Vortex Breaker

Equipment Outline

Process Line

Instrumentation Line

Slope

Redundant

Undefined Instrument Signal

Pneumatic Signal (Air)

Pneumatic Signal (Nitrogen)

Instrument Capillary Tubing (Filled)

Hydraulic Signal

Instrument Electrical Signal

System Link (Software)

Ultrasnonic Signal

Centrifugal

Liquid Seal

Rotary Screw

Reciprocating

Generic Blower

Centrifugal Blower

Rotary Blower

Axial Fan

Propeller

Electric Generator

Centrifugal Pump (Horizontal)

Centrifugal Pump (Verical)

Sump Pump

Wet-Pit Pump

Gear Pump

Rotary Pump

Vane Pump

Screw Pump

Reciprocating Pump

Hand Pump

Diaphragm Pump

Air Motor

Steam Turbine

Hydraulic Turbine

Expander

Double Flow Steam Turbine

Gas Turbine

Steam Engine

Diesel Engine

Gas Engine

Electric Motor (Seperate)

Electric Motor (Integral)

Monitor

Elevated Monitor

Remote Monitor

Foam Monitor

Fire Hydrant

Eye Wash

Spray

Safety Shower

Safety Shower and Eye Wash

Hose Station

Continuation Drawing No

Tie-In Tag

Rev Triangle

P&ID standards

P&ID Symbols for identifying asset types/
Field and Remote instrumentation symbols and codes/
Standardising notes as short codes/
Equipment, Pipelines and asset identifcation codes for asset management/
Company Number: 16047925
Neonex Digital Ltd, Chelmsford, Essex, CM1 6HU
© 2025 Neonex Digital Ltd. All Rights Reserved.

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