Full definition
A globe valve is a type of valve that features a spherical body with an internal baffle that divides the flow path, allowing for precise throttling and control of fluid movement. The disc or plug of the valve moves axially against a seat that is oriented perpendicular to the flow. This design provides a greater pressure drop compared to other valve types such as ball or gate valves, but it excels in terms of control capability and tight shutoff. Globe valves can be used in a variety of applications, including water, steam, gas, and light oils, and are available in sizes ranging from 1/2" to 24". The typical flow coefficient (Cv) for globe valves ranges from 10 to 600, which helps determine the flow capacity through the valve at a specified pressure drop. The maximum temperature for globe valves can reach up to 600°C when constructed with stainless steel, making them suitable for high-temperature applications.
The actuation of globe valves can be manual, electric, or pneumatic, depending on the specific needs of the application. Manual actuators are often used in simpler setups, while electric and pneumatic actuators allow for remote operation and integration into automated systems. The choice of actuator can significantly affect the valve's response time and overall efficiency in controlling flow. Globe valves are widely used in industries that require precise flow management, such as chemical processing, oil and gas, and power generation.
Standards such as ASME B16.34 and API 623 govern the design and manufacturing of globe valves, ensuring that they meet safety and performance requirements. These standards cover aspects such as materials, pressure-temperature ratings, and testing procedures, providing guidelines for selecting the right valve for specific applications. Proper selection and installation of globe valves are crucial to achieving optimal performance and reliability in fluid control systems.