Pidgeon guide
Everything you need to draw, check and export a diagram. Ten minutes, start to finish.
Getting started
- Open the editor. It loads an example process; use New or Templates to start your own.
- Choose the drawing Type in the toolbar: PFD, P&ID or SU assembly. The symbol palette, default line and title block follow your choice.
- Your work saves itself in this browser. To keep a copy or move it to another computer, use Save & export → Save diagram (.json), then Open it elsewhere.
Drawing basics
- Add a symbol: drag it from the palette on the left, or click it to drop it in the middle of the view. Search the palette by name, for example column or lyo.
- Connect: hover a shape to show its connection points, then drag from one to another shape. Larger shapes have extra, smaller points that act as nozzles.
- Put a part into a line: drop a valve, fitting, filter or inline instrument onto an existing line. The line splits and the part turns to follow the flow. This also works for an unconnected part already on the drawing.
- Branch a line: drop a Junction / tee onto it, then draw from its free side.
- Edit text: double-click a shape or line. Everything else is in the panel on the right.
- Rotate with R. Connected lines stay attached.
- Connection markers such as Tri-Clamp, weld or aseptic connector go on a line: drag one from the palette near a line end to mark that end, or onto the middle for an inline joint. Turn on Sizes to show their sizes.
Process flow diagrams
Use the unit-operation symbols for upstream, harvest, purification, fill–finish and oral solid dose. Add Cleanroom zones (EU GMP Annex 1 grades) behind equipment, and tick Single-use component on anything disposable to show the SU badge. The legend lists only the line types and markers you used.
P&IDs
Instruments
Type the tag as letters and loop number, for example PIT 201. In the panel, choose where the function is implemented (discrete, DCS, computer or PLC) and where it is accessed (field, control room, local panel, behind panel); the symbol changes to match ISA-5.1. Control and on/off valves carry a fail position.
Lines
Select a line to fill in size, service, line number, pipe class and insulation. The tag, such as 1.5"-WFI-1001-SS-BPE-SF4, appears once per line number when Tags is on. Auto-number line gives the next free number. Nozzle IDs (N1, N2…) go on each end.
Equipment
Volume, material, design pressure and temperature are under Equipment design data, and appear on the drawing if you choose to show them.
Single-use assemblies
Draw the assembly with bags, fittings, clamps and connectors, then select each tubing run to enter material, ID, OD and length. Place an Assembly boundary around the parts with its part number and sterilization method, and add a Bill of materials: it counts everything inside the boundary, groups connectors by size and totals tubing length by material and size.
Sheets
Use ＋ Sheet at the bottom of the canvas to add a sheet; the title block comes with it. The ⋯ menu on the current tab renames, duplicates, reorders or deletes it. To continue a line onto another sheet, select an Off-page connector, choose the sheet it continues on and click Create matching connector. Each connector then shows where it leads, and Go to sheet jumps there.
Saving and exporting
| Vector, one page per sheet. Choose A3, A4, 11 × 17, Letter or fit to drawing. | |
| DXF | AutoCAD R12, one file per sheet, millimetres (1 px = 0.265 mm). Layers by object type, CAD colours and linetypes. |
| PNG / SVG | The current sheet as an image. SVG pastes into Visio, PowerPoint and Word. |
| JSON | The editable drawing, all sheets. Reopen it with Open. |
Lists and drawing check
Reports exports the equipment list, line list, instrument index, valve list, connection schedule and bill of materials as CSV files that open in Excel. The drawing check above them lists problems such as duplicate tags, valves connected on one side only, lines missing data and unlinked off-page connectors; click one to go to it.
Keyboard shortcuts
| Delete | Delete selection |
| Ctrl + Z / Y | Undo / redo |
| Ctrl + C / V / D | Copy / paste / duplicate |
| R | Rotate 90° |
| F | Fit drawing to screen |
| Space + drag, or scroll | Pan |
| Ctrl + scroll | Zoom |
| Ctrl + PageUp / PageDown | Previous / next sheet |
| Enter or double-click | Edit text |
| Arrow keys (+ Shift) | Nudge 10 px (50 px) |
Changing the conventions
The service codes, pipe classes, insulation codes and tag prefixes are short lists near the top of app/index.html (SERVICES, SPECS, INSUL and each symbol's prefix). Edit them to match your site standard and host your own copy; it is a static page, so any web server or a shared drive will do.
Not validated software. Treat drawings as drafts until they are issued through your controlled document system.