Needle valve

ISO 10628-2 (group 21, valves) / PIP PIC001

Drawn as

Small bow-tie with a stem carrying a solid triangle pointing down onto the body (the needle), topped by a handwheel bar.

Meaning

Fine-throttling instrument valve, ½" and below: instrument roots, gauge isolation, sample and purge lines. Usually not modelled at plant scale.

Variants

Often drawn without the needle as a plain small bow-tie on an instrument impulse line
Instrument manifolds (2-, 3-, 5-valve) are drawn as boxes or groups of small valves