‌Pneumatic hard-seated butterfly valve‌ is a type of butterfly valve driven by a pneumatic actuator, with both sides of the sealing pair made of metal or other hard materials. It operates by rotating the valve rod to drive the butterfly plate, which in turn opens and closes the valve. During rotation, the butterfly plate moves the valve seat together, creating a seal. When the butterfly plate rotates to 90°, the valve is fully open, at which point only the thickness of the butterfly plate acts as a resistance to the fluid flow, resulting in very low flow resistance.

Operating Principle

The working principle of the pneumatic hard-seated butterfly valve is to use an air-powered device to provide power, driving the butterfly plate to rotate, thereby achieving the opening and closing of the valve. During the rotation, the butterfly plate drives the valve seat to rotate as well, creating a seal. When the butterfly plate rotates to 90°, the valve is fully open, at which point the flow resistance is very low.

Structural Features

The pneumatic hard-seated butterfly valve features a rational structural design, with a compact size and light weight, making it easy to install and operate. Its sealing surface is made of metal materials, precision machined and ground to ensure low leakage rates under high pressure differentials. The clever wedge design provides an automatic sealing function that becomes tighter as the valve is closed, with compensatory features between the sealing surfaces for zero leakage. The unique three-way offset design eliminates friction transmission between the sealing surfaces, extending the valve's service life.

Application Scenarios

Pneumatic hard-seated butterfly valves are widely used in various media and operating conditions, including oil, petrochemicals, power, iron and steel metallurgy, and wastewater treatment, among many others. They are suitable for a variety of media such as water, steam, oil, air, and gas, with a temperature range of -20℃ to +425℃. These valves are particularly suitable for applications requiring rapid opening and closing and high flow resistance.