In the world of industrial valves, understanding the differences between various types is crucial for selecting the right valve for specific applications. Two commonly used valves are trunnion valves and globe valves. As a trunnion valve supplier, I have in - depth knowledge of these valves and their applications. This blog aims to explore the differences between trunnion valves and globe valves in terms of application.
I. Trunnion Valves
Trunnion valves are a type of ball valve. They are designed with a trunnion - mounted ball, which means the ball is supported by a shaft (trunnion) at the top and bottom. This design provides several advantages that make them suitable for specific applications.
A. High - Pressure Applications
One of the primary applications of trunnion valves is in high - pressure systems. The trunnion - mounted ball design distributes the pressure evenly across the valve components. In high - pressure pipelines, such as those in the oil and gas industry, the force exerted on the valve can be extremely high. A trunnion valve can withstand this pressure without significant deformation. For example, in offshore oil platforms, where the pressure in the pipelines can reach thousands of pounds per square inch, trunnion valves are commonly used to control the flow of oil and gas.
B. Large - Diameter Pipelines
Trunnion valves are also well - suited for large - diameter pipelines. In large pipelines, the torque required to operate a valve can be substantial. The trunnion design reduces the operating torque because the ball is supported at two points. This makes it easier to open and close the valve, even in large - scale industrial settings. For instance, in long - distance natural gas transmission pipelines, trunnion valves are used to regulate the flow of gas over large distances.
C. Precise Flow Control in Certain Conditions
Although not as precise as globe valves in general flow control, trunnion valves can still provide relatively accurate flow control in specific situations. When the valve is in a partially open position, the trunnion - mounted ball can be adjusted to control the flow rate to a certain extent. This is useful in applications where a moderate level of flow control is required, such as in some chemical processing plants.
Our company offers a range of trunnion valves, including Forged Steel Fixed Ball Valve and Cast Steel Fixed Ball Valve. These valves are manufactured with high - quality materials and advanced technology to ensure reliable performance in various applications.
II. Globe Valves
Globe valves, on the other hand, have a different design and are suitable for different applications. A globe valve consists of a movable disk (plug) that moves perpendicular to the seat to control the flow of fluid.
A. Precise Flow Control
The most significant advantage of globe valves is their ability to provide precise flow control. The linear motion of the disk allows for fine - tuning of the flow rate. In applications where accurate flow regulation is essential, such as in pharmaceutical manufacturing, where the precise amount of a chemical reagent needs to be added to a reaction, globe valves are the preferred choice. The flow coefficient of a globe valve can be adjusted very precisely, enabling operators to control the flow with high accuracy.
B. Throttling Applications
Globe valves are also widely used in throttling applications. Throttling refers to the process of reducing the flow rate by creating a pressure drop across the valve. The design of the globe valve, with its constricted flow path, is well - suited for this purpose. In steam systems, for example, globe valves are used to throttle the steam flow to control the pressure and temperature in different parts of the system.
C. On - Off Service with Moderate Pressure
While globe valves can be used for on - off service, they are not as efficient as trunnion valves in high - pressure on - off applications. However, in applications with moderate pressure, such as in some water treatment plants, globe valves can be used to start and stop the flow of water.
III. Comparison of Applications
A. Flow Control Precision
As mentioned earlier, globe valves have a clear advantage in terms of flow control precision. Trunnion valves are more suitable for applications where a quick on - off operation or a moderate level of flow control is required. For example, in a power plant's cooling water system, if a precise amount of water needs to be added to the cooling tower, a globe valve would be a better choice. But in the main steam pipeline, where the valve is mainly used for on - off control, a trunnion valve would be more appropriate.
B. Pressure Resistance
Trunnion valves are designed to handle high - pressure applications better than globe valves. The trunnion - mounted ball design distributes the pressure evenly, reducing the stress on the valve components. In contrast, globe valves may experience more stress on the seat and disk in high - pressure situations, which can lead to premature wear and failure. Therefore, in high - pressure oil and gas pipelines, trunnion valves are the standard choice.
C. Pipeline Size
Trunnion valves are more suitable for large - diameter pipelines due to their lower operating torque. Globe valves, on the other hand, can be used in a wide range of pipeline diameters, but they may face challenges in very large - diameter pipelines due to the high torque requirements. In a refinery with large - diameter pipelines for transporting crude oil, trunnion valves are often used, while in smaller - diameter pipelines within the refinery for transporting chemicals, globe valves may be more common.
D. Application Environment
In corrosive environments, the choice between trunnion valves and globe valves also depends on the material selection. Trunnion valves can be made with corrosion - resistant materials such as stainless steel or alloy steel, which makes them suitable for use in chemical plants or offshore environments. Globe valves can also be made with corrosion - resistant materials, but their design may make them more prone to corrosion in some areas, such as the seat and the stem.
IV. Conclusion and Call to Action
In conclusion, trunnion valves and globe valves have distinct differences in terms of application. Trunnion valves are ideal for high - pressure, large - diameter pipelines and applications where a moderate level of flow control is required. Globe valves, on the other hand, excel in precise flow control and throttling applications.
If you are in need of trunnion valves for your industrial applications, our company is a reliable supplier. We have a wide range of products, including Forged Steel Fixed Ball Valve, which are manufactured to the highest quality standards. Our team of experts can help you select the right valve for your specific needs. If you are interested in learning more about our products or would like to discuss a potential purchase, please feel free to contact us. We look forward to the opportunity to work with you and provide you with the best valve solutions for your business.
References
- Valve Handbook, by David W. Miller
- Industrial Valves: Selection and Sizing, by Robert E. Schexnayder
