The set of schematic symbols laid down in ISO 3753 and DIN 28401 for drawing vacuum systems, with a distinct symbol for each pump type (rotary vane, Roots, turbo, diffusion, cryo, ion) plus gauges, valves, traps, flanges and lines. A correct diagram lets anyone trace the gas path from chamber to exhaust, see which valve isolates what and know where each gauge reads. Field techs work from these drawings when they lock out and vent a system.
P&ID shows the vacuum symbol for a cold trap that isn't on the tool, red-line the drawing before the audit.
Also heard as
- vacuum schematic symbols
- graphical symbols
Related terms
Stack
Shop name for the whole column of high vacuum pump, valves, trap and backing line that pumps a chamber.
Gate valve
Full-bore valve with a sliding plate that isolates a high vacuum pump or a load lock from the chamber.
Foreline
Pipe that connects the exhaust of a high vacuum or booster pump to its backing pump.
Turbomolecular pump
High vacuum pump whose rotor blades spin at tens of thousands of rpm and bat molecules toward the exhaust.