Structure and Principle of Double Eccentric Semi-Ball Valves

The double eccentric semi-ball valve is an advanced industrial valve commonly used in fluid pipelines to control the flow, connection, and distribution of fluids. Its operation is based on the rotation of the main control valve, which provides significant advantages such as easy operation, a frictionless opening process, zero leakage, and a long service life. These features make the double eccentric semi-ball valve an ideal choice for industrial applications, especially in situations where high sealing performance and durability are required.

Working Principle

The working principle of the double eccentric semi-ball valve employs an innovative design that ensures efficient fluid control. When the valve opens, the semi-ball body inside the valve is pressed against the valve seat by the action of the valve stem. As the control worm gear rotates counterclockwise, the valve stem also turns in the opposite direction, successfully disengaging from the valve seat. The semi-ball body then rotates to the fully open position without friction, guided by the guide pin. To close the valve, the worm gear is turned clockwise, lowering the valve stem. When the semi-ball reaches a 90° position, the angular surface compresses the semi-ball against the valve seat, effectively closing the valve.

Structural Features

The structural design of the double eccentric semi-ball valve not only focuses on ease of operation but also fully considers sealing performance and durability, ensuring stable operation in various complex conditions. Here, we will explore the main structural features of the double eccentric semi-ball valve that give it significant advantages in practical applications.

1. Sealing Design

Bimetallic Materials: Both the valve core and seat are made of bimetallic materials, forming a hard seal with a metal semi-ball surface. This ensures excellent sealing performance even in high-temperature and high-pressure environments.
Semi-Ball Line Contact: The contact between the valve core and seat is designed as a semi-ball line contact, using a three-dimensional eccentric principle to achieve zero leakage and minimize wear on the sealing surfaces during operation.

2. Compensation Design

The valve core is designed with an appropriate amount of compensation, allowing for adjustments after long-term use. When wear on the sealing surfaces is detected, simply loosening the limit bolt on the handwheel side and making a slight rotation during closure will restore a reliable seal, significantly extending the service life.

3. Maintenance-Friendly Design

The valve is designed for easy disassembly of the compression sleeve, facilitating adjustments or replacements of the valve seat. This design effectively avoids the problem of many valves being completely scrapped due to seal failure, improving the valve's cost-effectiveness and maintainability.

4. Efficient Fluid Path

The internal structure of the valve optimizes the fluid path, reducing flow resistance and improving fluid efficiency, ensuring the overall system operates effectively.

Performance Advantages

The double eccentric semi-ball valve showcases remarkable performance advantages due to its advanced design and high-quality materials, making it an ideal choice for many industrial applications. These advantages enhance the valve's operational efficiency and safety, providing significant economic benefits to users. Below, we will discuss the main performance advantages of the double eccentric semi-ball valve.

1. Compact Design

The valve has a compact design that occupies minimal space, making it easy to install and maintain. This compactness is suitable for various working conditions and facilitates transportation, reducing logistics costs.

2. Durability

The valve body is made from high-quality materials with excellent corrosion resistance and wear resistance, ensuring reliable operation in harsh environments. This durable design enhances the overall reliability of the system.

3. High-Performance Sealing

The sealing between the seat and the valve body employs a hard sealing design suitable for high-temperature and high-pressure conditions, ensuring reliable sealing performance. The small contact area between the seat and body and the high precision required for their sealing surfaces guarantee good sealing effectiveness even under high-pressure environments.

4. Automatic Alignment Function

The sealing between the seat and the semi-ball body adopts a two-point hard sealing design, with a gap between the seat and body that allows for automatic alignment during assembly, utilizing the positioning function of the semi-ball body. This ensures full contact between the sealing surfaces of the seat and the semi-ball body, resolving leakage issues caused by machining precision errors and improving overall valve performance and longevity.

5. Easy Maintenance

The valve's design allows for quick repairs and maintenance in the event of failure or performance decline, reducing downtime and improving production efficiency.

Conclusion

In summary, the double eccentric semi-ball valve stands out in the field of industrial fluid control due to its unique design and outstanding performance. Its frictionless operation, excellent sealing capabilities, and long-lasting durability make it an ideal choice in high-demand working conditions. With continuous technological advancements, the double eccentric semi-ball valve will exhibit greater potential and value in broader application fields, providing strong support for the efficiency, reliability, and safety of industrial production.