COMMON VALVE TYPES
Globe Valves
The families that appear on first RFQs and Chinese export quotes. Shared names are not interchangeable designs.
Choosing Globe Valves
A globe valve moves a plug or disc toward a seat across a changing flow path. Isolation versions and throttling versions can share a similar external shape, but their plugs and operating requirements differ. Compared with an unobstructed gate passage, the route through a globe valve can impose a larger pressure loss.
What to include in the RFQ
- Separate manual shut-off from repeated throttling or automatic control in the duty description.
- Request the plug style, seat material, flow coefficient and permitted installation direction.
- Give maximum differential pressure and ask how stem thrust or a balancing arrangement is selected.
- Check packing or bellows construction, maintenance access and the pressure-temperature envelope.
A published design example
Spirax Sarco distinguishes the BSK isolation version from the BSKT throttling-plug version; this illustrates why a specific trim matters within one globe-valve family.
Selection scenario
On a steam branch, establish whether the valve is for maintenance isolation or adjustable flow. A buyer who needs both should obtain written confirmation of the offered trim and closing differential, rather than rely on a handwheel photograph.
Common selection mismatch
A globe body with an isolation plug is not automatically a modulating control valve. The trim, actuator and sizing calculation must match the requested service.