Steam tracing mark
ISO 10628-2 (group 25) / PIP PIC001 (line conventions)
Drawn as
A process line with a thin dashed tracer line beside it, marked "ST", usually ending at a steam trap.
Meaning
Steam- or hot-oil-traced line. Mostly onshore and in refineries; rare offshore. Note it on the line.
Variants
- Hot-water or glycol tracing: same, marked "WT" or "GT"
- Jacketed lines are drawn differently (see the jacketed line)
Tags
ST
Not physical hardware. Read it, then skip it in the 3D model.