A globe valve is a linear motion valve device, which is primarily designed and used extensively to commence, end, and regulate the flow of a fluid. It is used as a start and stops device for fluid pathways. The disk part of a globe valve can be completely detached and removed from the path of fluid flow, or it can be used to completely block the path and stop the flow of the fluid.
Usually, most industries and companies use a globe valve for isolation purposes and throttling services.
Although these valves show a slightly higher pressure drop than straight-through valves ( for example, gate valve, plug valve, ball valve, et cetera), they may also be used where the pressure drop throughout the valve tube is not a major controlling factor.
The globe valve is mostly used for throttling and regulating the control of the fluid flow. A complete fluid flow stop, or a shut-off, is done by moving the disc of the globe valve against the direction of flow of the fluid stream, rather than just across it, as was the case with the gate valve.
The pattern of fluid flow through the globe valve includes, and is not limited to, changes in the direction of flow of the fluid stream, which results in higher resistance to the flow of the fluid. This causes a high-pressure drop in the valve.
The globe valve is an excellent and sturdy valve to use in high-pressure operations of steam and other fluid mediums. Good globe valves are manufactured by globe valve manufacturers with quality materials in well-equipped factories.
The advantages and disadvantages of globe valves are given below-
ADVANTAGES:
- Globe valve has an excellent shutoff capability
- It has a moderate to good throttling capability
- It has a much shorter stroke as compared to a gate valve
- It is available in tee, wye, and angle patterns. Each of the globe valves offers unique capabilities to the system
- It makes the mechanism smoother and makes the machine more comfortable to use. It also makes it much easier to resurface the seats
- When the disc is not attached to the stem, the globe valve can also be used as a stop-check valve
DISADVANTAGES:
- It has a much higher pressure drop as compared to a gate valve
- It requires a much higher force or a more significant actuator mechanism to seat the valve, with pressure under the seat
- It throttles the flow of fluid under the seat and also shuts off the flow of fluid over the position.
Some of the standard applications of globe valves-
- It is used in cooling water systems, where the flow of fluid needs to be regulated regularly
- The fuel oil system where the flow of the liquid is controlled and leakproof-ness is of the highest importance
- It has high-point vents and low-point drains, for which leakproof-ness and safety are among the most significant considerations
- It has a feedwater system, chemical feed system, condenser air extraction system, and extraction drain systems
- It also has boiler vents and drains, central steam vents and drains, and heater drains
- It has turbine seals and flows, and turbine lube oil system and many other systems