Gate valve vs globe valve: differences and where to use each
Gate valves and globe valves are often confused, but they are different valve classes. A gate valve opens or closes a line with minimal loss. A globe valve seals more tightly and can throttle, but the flow follows a tortuous path through it.
TAZ Engineering Team · · 6 min
Design
In a globe valve a disc moves onto a seat along the flow axis, and the body turns the flow through the seat. The stroke is short, so the valve closes in a few turns. In a gate valve the wedge crosses the full bore.
Flow resistance
An open globe valve has a resistance coefficient several times higher than a gate valve. On a pumped line that is a direct energy cost, which is why globe valves are rarely made above DN 200–300.
Tightness and steam
The globe valve seat works in compression rather than sliding, so it holds steam and high differential pressure better and wears less with frequent cycling. It is the standard valve for small and medium steam lines, drains and blowdowns.
Throttling
A globe valve can throttle because flow passes through an annular gap. A gate valve must not be left partly open: the wedge vibrates and the seats erode.
Selection rule
Gate valve: large DN, minimum loss, infrequent operation. Globe valve: steam, small DN, frequent operation, tight shut-off or coarse throttling. Install globe valves according to the flow arrow on the body. TAZ makes steel globe and gate valves for water, steam and oil products.
Checklist
- DN
- medium and temperature
- operating frequency
- throttling need
- allowable pressure loss
- flow direction
- actuation