Overview

Trunnion mounted pneumatic ball valves are equipped with floating seats. When the medium pressure acts on the valve, the seats move to press the sealing ring tightly against the ball, ensuring reliable sealing performance. Bearings are installed on the upper and lower shafts of the ball, which reduces the operating torque significantly, making the valve suitable for high-pressure and large-bore applications. In recent years, oil-sealed ball valves have been developed to further optimize performance: special lubricating oil is injected between the sealing surfaces to form an oil film, which not only enhances the sealing effect but also reduces the operating torque, making the valve more suitable for high-pressure, large-bore and high-demand working conditions.

Working Principle

This valve is available in two body structures: two-piece and three-piece, with the middle flange connected by bolts. The seal adopts reinforced PTFE embedded in a stainless steel ring, and a spring is installed at the rear of the steel ring to ensure that the valve seat is closely attached to the ball, maintaining a stable seal. PTFE bearings are installed on the upper and lower valve stems to reduce friction, making the operation more labor-saving. An adjusting plate is installed at the bottom of the valve stem to ensure the accurate alignment between the ball and the seal, ensuring the sealing effect. The valve adopts a full-port design, where the flow hole is consistent with the inner diameter of the pipeline, facilitating pipeline cleaning. It is matched with an electric valve positioner, and can realize automatic operation by inputting 420mA DC signal and 0.40.7MPa air source, realizing the adjustment of pressure, flow, liquid level and other parameters.

Application Fields

As a high-performance pneumatic valve, the trunnion mounted pneumatic ball valve is widely used in long-distance transmission pipelines and industrial production fields. It is specially designed with enhanced strength and anti-corrosion performance to adapt to various harsh working environments. Compared with floating ball valves, when this valve works, the fluid pressure acting on the ball is fully transmitted to the bearing through the trunnion, which avoids the displacement of the ball towards the valve seat, thus reducing the deformation of the valve seat, ensuring stable sealing performance and prolonging the service life. It is suitable for conveying corrosive and non-corrosive media, and can be flexibly installed according to actual needs without direction restrictions due to its bidirectional sealing performance.

Structural Features

1. The trunnion mounted pneumatic ball valve adopts a fixed ball design, and the relative moving parts are made of self-lubricating materials with extremely low friction coefficient, which effectively reduces the operating torque; the long-term sealed lubricating grease ensures the flexibility and stability of the valve operation.

2. It is available in full-port or reduced-port designs, with small flow resistance, which can meet the requirements of different flow rates.

3. The trunnion mounted structure is adopted, and a preload spring is added to the valve seat, which enables the valve to have an automatic pressure relief function, ensuring the safe operation of the system.

4. Each valve is equipped with two movable sealing seats, which can realize bidirectional sealing, so there is no need to consider the direction of the medium during installation, which is more convenient and efficient.

5. It is equipped with a fireproof and anti-static structure: conductive springs are installed between the valve stem and the valve body, and between the valve stem and the ball, to avoid static sparks and ensure the safety of the system.

6. It has a fire-resistant structure for double protection: in case of fire, the sealing part can form a metal-to-metal hard seal, avoiding medium leakage and ensuring the safety of the system.

Technical Parameters