Wear Resistance: Since the core of a hard-sealed ball valve features a spray-welded alloy steel surface and the sealing ring utilizes a build-up welded alloy steel layer, the valve experiences minimal wear during opening and closing operations. (Its hardness rating falls within the range of HRC 65–70.)
Excellent Sealing Performance: The sealing surfaces of a hard-sealed ball valve undergo a meticulous manual lapping process; the valve is only deemed ready for service once the valve core and sealing ring achieve a perfect, flush fit. Consequently, its sealing performance is highly reliable.
Effortless Operation: The sealing ring of a hard-sealed ball valve is backed by a spring mechanism that maintains a tight, constant contact between the ring and the valve core. As a result, the valve opens and closes with remarkable ease-requiring minimal external force-once the applied torque exceeds the spring's initial preload.
Extended Service Life: These valves have been widely adopted across diverse sectors-including petroleum, chemical processing, power generation, papermaking, nuclear energy, aviation, and rocketry-as well as in various applications within daily life.
Pneumatic ball valves feature a simple, compact structure, reliable sealing capabilities, and ease of maintenance. Since the sealing surface and the spherical ball remain in constant contact while in the closed position, they are highly resistant to erosion by the flowing medium. Furthermore, they are easy to operate and service, making them suitable for use with general working media such as water, solvents, acids, and natural gas. Their primary function is to isolate (shut off) or connect the flow of media within a pipeline, though they can also be utilized for fluid regulation and control.
Compared to other types of valves, pneumatic ball valves offer angular-stroke torque output, rapid and smooth opening/closing operations, and broad applicability. They also possess the following specific advantages:
1. Thrust Bearings: The inclusion of thrust bearings minimizes the frictional torque acting on the valve stem, thereby ensuring smooth, flexible, and reliable long-term operation of the stem.
2. Anti-Static Function: Springs are strategically installed between the ball, the valve stem, and the valve body to effectively dissipate any static electricity generated during the opening and closing process.
3. Extended Service Life: Materials such as PTFE (polytetrafluoroethylene) exhibit excellent self-lubricating properties, resulting in minimal frictional loss against the valve ball; this characteristic contributes significantly to the long service life of pneumatic ball valves.
4. Low Fluid Resistance: Among all valve classifications, the pneumatic ball valve offers the lowest fluid resistance. Even in the case of reduced-bore pneumatic ball valves, the resistance to fluid flow remains remarkably low.
5. Reliable Stem Sealing: Since the valve stem performs only rotational movement-rather than linear (rising/lifting) movement-the stem's packing seal is less susceptible to wear and damage. Moreover, the sealing capability of the stem seal actually increases in proportion to the rising pressure of the flowing medium.
6. Excellent Seat Sealing Performance: Utilizing sealing rings made from elastic materials-such as PTFE-the valve features a structure that facilitates effective sealing; furthermore, the sealing capability of the pneumatic ball valve increases in tandem with rising media pressure.
7. Low Fluid Resistance: Full-bore ball valves exhibit virtually no flow resistance.
8. Simple Structure: Compact in size and lightweight.
9. Tight and Reliable Sealing: Featuring two sealing surfaces, ball valves commonly employ various plastics for their sealing materials, ensuring excellent tightness and the capability to achieve a completely leak-proof seal. They are also widely utilized in vacuum systems.
10. Convenient Operation: Quick to open and close, requiring only a 90-degree rotation to transition from fully open to fully closed, thereby facilitating remote control.
11. Easy Maintenance: The ball valve features a simple structure, and its sealing rings are typically movable components, making disassembly and replacement relatively convenient.
12. Protection of Sealing Surfaces: When in the fully open or fully closed position, the sealing surfaces of the ball and seat are isolated from the flowing media, preventing erosion of the valve's sealing surfaces as the media passes through.
13. Wide Range of Applications: Suitable for nominal diameters ranging from a few millimeters up to several meters, and applicable across a spectrum from high-vacuum environments to high-pressure conditions.
14. Self-Wiping Action: Due to the self-wiping effect that occurs during the opening and closing process, ball valves are suitable for use with media containing suspended solid particles.
15. Limitations: Characterized by high manufacturing precision and a relatively high cost; not recommended for use in high-temperature environments; furthermore, if impurities are present within the pipeline, the valve is susceptible to clogging by these impurities, which may prevent it from opening.
