What is a Globe Valve, and Its Applications.
What is a globe valve?
A globe valve is a type of valve used in various fluid control systems. Here is a detailed introduction:
1.Structure
- Body: The body of a globe valve is usually made of metal materials such as cast iron, carbon steel, or stainless steel. It has an inlet and an outlet, and the fluid flows through the valve body.
- Disc and Stem: The disc is connected to the stem. When the stem rotates, it causes the disc to move up and down. The disc is the part that controls the flow of fluid by either blocking or allowing the fluid to pass through the valve’s opening.
- Seat: The seat is located at the bottom of the valve body. It provides a sealing surface for the disc to rest on when the valve is closed, ensuring a tight seal to prevent fluid leakage.
2.Working Principle
- Open state: When the operator turns the handwheel or actuator in the counterclockwise direction, the stem moves upward, lifting the disc away from the seat. This allows the fluid to flow through the valve from the inlet to the outlet with relatively low resistance.
- Closed state: Turning the handwheel or actuator in the clockwise direction causes the stem to move downward, bringing the disc to press against the seat. This blocks the flow of fluid, completely shutting off the passage and stopping the fluid from flowing through the valve.
3.Advantages and disadvantages
Globe valves have the following advantages:
- The structure is simple, making manufacturing and maintenance relatively convenient.
- The working stroke is short, and the opening and closing time is brief.
- The sealing performance is good, the friction between the sealing surfaces is small, and the service life is relatively long.
The disadvantages of globe valves are as follows:
- The fluid resistance is large, and a relatively large force is required for opening and closing.
- It is not suitable for media with particles, high viscosity, or easy coking.
- The regulating performance is poor.
The applications of globe valves.
There are mainly the following fields:
- Water supply systems: They are commonly used in domestic and industrial water supply lines to control the flow of water to different areas or equipment.
- HVAC systems: In heating, ventilation, and air conditioning systems, globe valves are used to regulate the flow of hot or cold water through radiators, coils, and other components.
- Steam systems: Globe valves are suitable for controlling the flow of steam in power plants, industrial processes, and steam heating systems.
- Chemical and petrochemical industries: They are used to handle various chemicals and petroleum products, ensuring safe and precise control of fluid flow in pipelines and processing equipment.
