Globe valve, also known as cut-off valve, is the most widely used valve. Therefore, it is very popular for on-off services, as the friction between the sealing surfaces is small and it is more durable; the opening height is not large; the manufacturing is easy and the maintenance is convenient; it is not only suitable for medium and low pressure, but also for high pressure and ultra high pressure.
The closing principle is that, relying on the pressure of the valve stem, the sealing surface of the disc and the sealing surface of the valve seat are closely attached to prevent the medium from flowing.
The globe valve only allows the medium to flow in one direction, and it is directional when installed.
The action characteristic of a shut-off valve is that the closing member (disc) moves along the center line of the valve seat. Its function is mainly to cut off, and it can also roughly adjust the flow rate, but it cannot be used as a throttle valve.
According to the direction of the channel, the stop valve is divided into three categories:
1) Straight-through type: the inlet and outlet channels are in a straight line, but they must be turned 90° when passing through the valve seat.
2) Angle type: the inlet and outlet channels are at right angles.
3) Y type: The inlet and outlet channels are in a straight line and intersect the center of the valve seat. With this shut-off valve, the stem is tilted.
The straight-through stop valve is installed in a straight pipeline, and the most commonly used is easy to operate. However, the fluid resistance is large, and the direct current method is best for pipelines with strict requirements for resistance loss. However, the Y type valve stem is inclined and has a large opening height, which is inconvenient to operate. Angle type globe valves are installed in vertical cross pipes and are usually used for high pressure.
