Advantages of ANSI stop valves
The sealing principle of ANSI stop valves mainly depends on their unique structure and operating mechanism.

1. Sealing structure
ANSI stop valves are a type of forced sealing valves, and their sealing structure is usually composed of a valve disc sealing surface and a valve seat sealing surface. When the valve is closed, the valve disc sealing surface fits tightly against the valve seat sealing surface, forming a reliable sealing barrier to prevent the flow of the medium.

2. Sealing principle
01. Valve stem pressure
ANSI stop valves apply pressure to the valve disc through the valve stem, so that the valve disc sealing surface fits tightly against the valve seat sealing surface. This pressure is usually achieved by rotating the handwheel or other operating mechanism to ensure that the sealing surface does not leak when the valve is closed.

02. Wedge seal
In some ANSI stop valves, a wedge sealing structure is used between the valve disc and the valve seat. When the valve disc drops, its wedge-shaped part will mechanically wedge into the valve seat to form a tighter seal. This structure enables the valve to maintain good sealing performance even under high pressure differentials.

03. Self-cleaning function
During operation, the ball and seat of the American standard stop valve will tilt away. This phenomenon causes the fluid to flow in an arc shape inside the sealing surface, and the high-speed impact force generated by the flow will remove impurities attached to the spherical surface, achieving the purpose of self-cleaning. This helps to keep the sealing surface clean and smooth and extend the life of the seal.

3. Sealing materials
The sealing surface of the American standard stop valve is usually made of wear-resistant, high-temperature resistant, and corrosion-resistant materials, such as surfacing cobalt-based cemented carbide. These materials have excellent mechanical properties and chemical stability, and can maintain the stability and reliability of sealing performance under harsh working conditions.

4. Sealing performance evaluation
In order to ensure that the sealing performance of the American standard stop valve meets the relevant standards and requirements, strict sealing performance tests are usually required. These tests include pressure tests, leakage tests, etc. to evaluate the sealing performance and reliability of the valve under different working conditions.