Globe valve

How to read it

A globe valve controls flow by moving a disk or plug straight toward or away from a seat. The DOE’s Mechanical Science handbook calls it a valve used to stop, start and regulate flow: as the disk closes, the gap around it narrows gradually, which gives the globe valve good throttling ability. Kuphaldt’s Lessons In Industrial Instrumentation calls the globe one of the most popular sliding-stem designs in throttling service.

On a P&ID, the filled dot in the middle is what separates it from the plain gate valve in both the DOE’s chart and Kuphaldt’s. The DOE’s chart also lists the plain pair of triangles as an alternative globe symbol, and its handbook notes that globe and gate valves are often drawn the same way, leaving the type to the component number or the drawing’s legend.

Also searched as: globe valve p&id symbol, globe valve symbol.

Look-alikes

A hollow circle in place of the dot is a ball valve. Both triangles shaded solid is a valve shown closed, in Kuphaldt’s chart, rather than a globe valve. With a dome, a box or another actuator on a stem above it, the valve body is part of a control valve.