Structure of globe valve

The structure of a globe valve consists of several key components that work together to control the flow of fluids. Here is an overview of the structure of a typical globe valve:

1. Body: The body is the main casing of the valve and houses all the internal components. It is usually a globular or cylindrical shape and has threaded or flanged ends for connection to the pipeline.

2. Bonnet: The bonnet is a cover that is attached to the top of the valve body. It provides a seal and encloses the stem and other internal components. The bonnet is typically bolted or threaded onto the body.

3. Disc or Plug: The disc or plug is the movable element inside the valve that controls the flow of fluid. It is connected to the stem and can be raised or lowered to regulate the flow by engaging or disengaging with the seat.

4. Seat: The seat is a sealing surface located inside the valve body against which the disc or plug rests when the valve is closed. It ensures a tight seal and prevents leakage when the valve is in the closed position.

5. Stem: The stem is a long, slender rod that connects the handwheel or actuator to the disc or plug. When the handwheel or actuator is turned, it rotates or moves the stem, which in turn raises or lowers the disc or plug to control the flow.

6. Handwheel or Actuator: The handwheel is a manual control mechanism attached to the top of the valve for operating the valve by hand. In some cases, an actuator, such as a pneumatic or electric actuator, is used to automate the valve operation.

7. Backseat: Some globe valves feature a backseat design. The backseat is a secondary seating surface located at the top of the stem. When the valve is fully opened, the stem is raised, and the disc or plug is positioned against the backseat, providing a secondary seal.

8. Packing: The packing is a sealing arrangement around the stem that prevents leakage along the stem. It consists of packing material, such as braided graphite or PTFE, that is compressed using a packing gland to create a seal.

9. Ports: Globe valves have inlet and outlet ports or openings through which the fluid flows. The fluid enters the valve through the inlet port, passes around the disc or plug, and exits through the outlet port.

It's important to note that while the basic structure of a globe valve remains consistent, there may be variations in design, materials, and configurations depending on the specific application and manufacturer.