Pneumatic Circuit Simulator
Drag & Drop • ISO 1219 Symbols • Animated Air Flow • 39 Components • Pre-Built Circuits — Simulate • Explore • Practice • Quiz
1 Overview
Welcome to the Pneumatic Circuit Simulator — a free, browser-based pneumatic systems simulator designed for mechanical engineering students, automation technicians, vocational instructors, and maintenance engineers. This tool serves as a powerful FluidSIM pneumatics online alternative, providing interactive ISO 1219 schematic building, real-time compressed air flow animation, and comprehensive learning modes — all without installation, signup, or licensing fees.
The simulator features 39 pneumatic components including FRL units, 5/2 valves, timer valves, logic gates, vacuum generators, and more. It includes 9 pre-built circuit templates and 4 interactive learning modes (Simulate, Explore, Practice, Quiz). Calculate cylinder force, air consumption, and study circuits ranging from basic direct control to multi-cylinder cascade sequencing.
2 Getting Started
Select components from the collapsible palette on the left. Click a component to place it on the canvas, or drag it directly. Click on port circles to create connections between components. Click the Run Circuit button to start the simulation and watch compressed air flow through your circuit with animated particles.
Load a pre-built circuit (Direct Control, Speed Control, Auto Return, AND/OR Logic, Time Delay, Sequential, Cascade, or Vacuum Pick) to instantly study a working configuration. Or build from scratch using the 39 available ISO 1219 components.
3 Component Library — 39 ISO 1219 Components
Air Supply (2): Compressed air source and air reservoir tank.
Air Treatment / FRL (3): Filter, pressure regulator, and combined FRL unit for clean, regulated air.
Directional Control Valves (12): 2/2 on/off, 3/2 valves (push button, roller lever, idle return, plunger, solenoid), 5/2 valves (single/double solenoid, pilot), 5/3 valves (closed/exhaust centre), and 4/3 closed centre. ISO 5599 port numbering: 1(P), 2(A), 3(R), 4(B), 5(S).
Flow Control (3): One-way flow control (meter-out), throttle valve, quick exhaust valve.
Pressure Control (2): Relief valve, sequence valve.
Logic Valves (3): Check valve, shuttle valve (OR), dual-pressure valve (AND).
Actuators (4): Single-acting cylinder, double-acting cylinder, rodless cylinder, rotary actuator.
Vacuum (2): Venturi vacuum generator, suction cup.
Timing (2): On-delay and off-delay timer valves.
Measurement (3): Pressure gauge, flow meter, proximity sensor.
Utility (2): Silencer, T-connector.
4 Building & Simulating Circuits
Components are organised into collapsible categories in the palette. Drag or click to place on canvas. Click port circles to connect components with automatically routed orthogonal paths. Drag connection segments to adjust routing.
9 Pre-Built Templates: Direct Control, Speed Control, Auto Return, AND Logic (two-hand safety), OR Logic, Time Delay, Sequential A+B+, Cascade, and Vacuum Pick.
Simulation: Animated blue particles show air flow direction and speed. Click 3/2 push buttons to toggle during simulation. Pressure gauges show live readings. Cylinders animate extension/retraction. Readout panel shows supply pressure, flow rate, air consumption, cylinder force, and speed.
Manipulation: Rotate (R), Duplicate (D or right-click), Delete (Delete), Undo (Ctrl+Z). Right-click for context menu.
5 Explore, Practice & Quiz
Explore provides 16+ concepts across Fundamentals (Boyle's Law, flow, force), Components (valves, cylinders, FRL), Circuits (speed control, sequencing, cascade), and Applications (pick-and-place, clamping, sorting). Formulas, worked examples, and practical tips included.
Practice offers 12 randomised problems on cylinder force, piston speed, air consumption, flow rate, valve sizing, and pressure drop with step-by-step solutions.
Quiz tests with 5 randomly selected questions from a pool of 15 covering valve types, circuit design, calculations, and ISO standards.
6 Canvas Tools & Annotations
Annotation Toolbar: Use the marking toolbar above the canvas to annotate your circuit diagrams. Tools include Move (select, drag, resize annotations), Sketch (freehand drawing with pressure sensitivity, multiple colors and widths), and Shapes (rectangles, circles, ellipses, arrows, lines, double-arrows, and text labels).
Selection & Editing: Click any annotation to select it — a dashed selection box with corner handles appears. Drag inside the box to move, drag corners to resize, or use the action icons above the selection to rotate (15° increments), duplicate, or delete. Double-click a text label to edit it.
Zoom & Pan: Use the zoom toolbar (bottom-left) or keyboard shortcuts: Ctrl+= zoom in, Ctrl+- zoom out, Ctrl+0 reset view, Ctrl+1 fit all components. Zoom with Ctrl+Scroll (mouse) or pinch-to-zoom (touch). All elements — grid, components, connections, particles, and annotations — zoom together.
Pan Mode: Press H or right-click on empty canvas to toggle pan mode (yellow indicator on toolbar). Drag to pan the view. Press Escape to exit. Alternatively, hold Ctrl and drag to pan without entering pan mode.
Fullscreen: Click the ☶ button (top-right of canvas) for fullscreen mode with the component palette, toolbar, and readouts all visible.
Export & Toggle: Click 📷 to export the canvas as a PNG image with watermark. Use the 👁 eye icon to show/hide all annotations. Use the 🧹 Clear button to clear annotations by category (all, sketches only, or shapes & text only).
7 Keyboard Shortcuts & Tips
Circuit Shortcuts: Space = Run/Stop, Ctrl+Z = Undo, Ctrl+Shift+Z = Redo, R = Rotate, D = Duplicate, Delete/Backspace = Delete, Escape = Cancel.
Zoom/Pan Shortcuts: Ctrl+= = Zoom in, Ctrl+- = Zoom out, Ctrl+0 = Reset view, Ctrl+1 = Fit all components, H = Toggle pan mode, Escape = Exit pan mode.
- Always include an FRL unit between the air supply and the circuit.
- Use meter-out flow control (not meter-in) for smooth cylinder speed control — compressed air is compressible, so meter-in causes jerky motion.
- Add silencers to all exhaust ports to reduce noise in real installations.
- Use quick exhaust valves directly at cylinder ports for maximum retraction speed.
- In sequential circuits, use one-way roller levers (idle return) to avoid false signals.
- Set supply pressure to 6 bar for standard industrial pneumatic applications.
- ISO 5599 port numbering: 1=supply, 2=output A, 3=exhaust A, 4=output B, 5=exhaust B.
- Hover over any button to see its keyboard shortcut in the tooltip.
Pneumatic Circuit Simulator — Build and Learn Compressed Air Systems Online
A pneumatic circuit uses compressed air (typically 4–10 bar) to power cylinders and actuators. Key components include an FRL unit for air preparation, directional control valves (3/2, 5/2, 5/3) to route airflow, flow control valves for speed regulation, and single-acting or double-acting cylinders. This free simulator lets you build ISO 1219 circuits with 39 components and simulate air flow in real time.
This free pneumatic circuit simulator lets you design, build, and simulate pneumatic circuits directly in your browser. Using ISO 1219 standard symbols, you can drag and drop 39 pneumatic components — from compressed air supplies and FRL units to 5/2 directional control valves, timer valves, vacuum generators, and logic gates — onto an interactive canvas and connect them to create working circuits. Watch compressed air flow through your circuit with animated particles, monitor real-time pressure and flow readings, and learn how pneumatic systems work through hands-on experimentation. This pneumatic trainer serves as a free FluidSIM pneumatics online alternative for students and technicians worldwide.
| Feature | Pneumatic | Hydraulic | Electro-Pneumatic |
|---|---|---|---|
| Working Medium | Compressed air | Hydraulic oil | Air + electrical signals |
| Operating Pressure | 4 – 10 bar | 50 – 350 bar | 4 – 10 bar |
| Speed | Fast (0.1 – 2 m/s) | Slow, precise | Fast, programmable |
| Force Output | Low – Medium | Very High | Low – Medium |
| Control Type | Pilot signals | Pilot / servo | Solenoid / PLC |
| Standard Valve | 5/2 DCV | 4/3 DCV | 5/2 solenoid |
| Exhaust | To atmosphere | Return to tank | To atmosphere |
| Environment | Clean, safe | Oil leak risk | Clean, flexible |
What Are the Main Components of a Pneumatic System?
Pneumatic systems use compressed air (typically at 4–8 bar) to transmit power and perform work. Unlike hydraulic systems that use incompressible oil, pneumatic circuits work with compressible air, which means actuator speed can be affected by load changes. The key components include an air compressor, FRL (Filter-Regulator-Lubricator) unit for air preparation, directional control valves (3/2, 5/2, 5/3) to route airflow, flow control valves for speed regulation, and actuators (cylinders, rotary actuators) that convert air pressure into motion. Understanding pneumatic circuit design is essential for automation, manufacturing, and industrial maintenance professionals.
What Are the Key Differences Between Pneumatic and Hydraulic Systems?
While both use fluid power, pneumatics operates at much lower pressures (4–10 bar vs 50–350 bar for hydraulics). Pneumatic circuits exhaust air to atmosphere through silencers, while hydraulic oil returns to a tank. Five-port valves (5/2, 5/3) are standard in pneumatics because each cylinder port needs its own exhaust path. Speed control uses meter-out (not meter-in) because compressed air is compressible — restricting inlet air causes jerky motion as pressure builds and releases. FRL units are mandatory in pneumatics to ensure clean, dry, lubricated air reaches the valves.
Who Uses This Pneumatic Circuit Simulator and Why?
This pneumatic training simulator is designed for engineering education (Technical and Vocational Education and Training) students studying mechatronics, industrial automation, and fluid power. Vocational instructors use it as a classroom teaching aid alongside physical pneumatic training rigs. Maintenance engineers use it to troubleshoot and plan modifications to existing pneumatic circuits. Automation engineers prototype new circuit designs before implementation. The four learning modes (Simulate, Explore, Practice, Quiz) provide a complete educational experience from theory to hands-on application.
What Are the Standard Pneumatic Circuit Symbols (ISO 1219)?
| Component | ISO Symbol | Function |
|---|---|---|
| 3/2 Way Valve | 3 ports, 2 positions | Directs air to extend or retract single-acting cylinder |
| 5/2 Way Valve | 5 ports, 2 positions | Controls double-acting cylinder — extend & retract |
| 5/3 Way Valve | 5 ports, 3 positions | Double-acting cylinder with centre stop position |
| Single-Acting Cylinder | One air port + spring | Extends by air pressure, retracts by spring return |
| Double-Acting Cylinder | Two air ports | Extends and retracts by air pressure |
| Flow Control Valve | Adjustable orifice + check | Controls actuator speed in one direction |
| Pressure Relief Valve | Spring-loaded poppet | Limits maximum system pressure for safety |
| Shuttle Valve (OR) | Two inlets, one outlet | Passes air from either input — logic OR function |
| Two-Pressure Valve (AND) | Two inlets, one outlet | Passes air only when both inputs present — logic AND |
| FRL Unit | Filter + Regulator + Lubricator | Conditions compressed air before entering the circuit |
What Are Common Pneumatic System Operating Parameters?
| Parameter | Typical Range | Unit |
|---|---|---|
| Supply Pressure | 4 – 10 | bar |
| Standard Working Pressure | 6 | bar |
| Low-Pressure Pneumatics | 0.5 – 2 | bar |
| Cylinder Force (bore 32 mm @ 6 bar) | ≈ 483 | N |
| Cylinder Force (bore 63 mm @ 6 bar) | ≈ 1 870 | N |
| Air Consumption (32 mm bore, 100 mm stroke) | ≈ 0.048 | L per cycle |
What Is a 5/2 Directional Control Valve?
A 5/2 directional control valve has 5 ports and 2 switching positions. Port 1 receives compressed air from the supply. In position 1, air flows from port 1 to port 2 (extending the cylinder) while port 4 exhausts through port 5. In position 2, air flows from port 1 to port 4 (retracting) while port 2 exhausts through port 3. It is the standard valve for controlling double-acting cylinders in pneumatic circuits.
What Is an FRL Unit in Pneumatics?
An FRL unit (Filter-Regulator-Lubricator) is an air preparation assembly placed between the compressor and the pneumatic circuit. The filter removes moisture, dust, and oil contaminants. The regulator reduces and stabilises supply pressure to the required working pressure (typically 6 bar). The lubricator adds a fine oil mist to lubricate valve spools and cylinder seals. The FRL is always placed at the air inlet of every pneumatic circuit.
What Is the Difference Between Single-Acting and Double-Acting Cylinders?
A single-acting cylinder uses air pressure for one stroke direction (usually extension) and a spring for the return stroke. It needs only one air port and a 3/2 valve. A double-acting cylinder uses air pressure for both extension and retraction, requiring two air ports and a 5/2 valve. Double-acting cylinders provide force in both directions and are used in most industrial applications.
What Is the Cascade Method in Pneumatics?
The cascade method is a systematic technique for designing multi-actuator pneumatic circuits that avoids signal conflicts. A signal conflict occurs when two opposing pilot signals reach a valve simultaneously. The cascade method divides the sequence into groups, using cascade valves to switch air supply between groups so that only one pilot signal is active at a time. It is the standard method taught in engineering education programs for circuits with 3 or more actuators.
What Is an Electro-Pneumatic Circuit?
An electro-pneumatic circuit combines electrical control with pneumatic actuation. Instead of pneumatic pilot signals, solenoid valves are switched by electrical signals from pushbuttons, sensors, relays, or PLCs. The pneumatic power circuit remains the same (cylinders, flow controls), but the control circuit uses electrical wiring, limit switches, and relay logic. Electro-pneumatic systems offer faster switching, easier sequence programming, and remote control capability. Try our Electro-Pneumatic Circuit Simulator to build these circuits.
Explore Related Simulators
If you found this pneumatic circuit simulator helpful, explore our Electro-Pneumatic Circuit Simulator, Hydraulic Circuit Simulator, Boyle's Law Simulator, and Stress-Strain Simulator for more hands-on practice.