Ball valves can employ either hard-seal or soft-seal structures, the choice depending on the application and requirements.
Hard-seal structures use a hard metal as the sealing material between the valve and seat, such as tungsten carbide or chromium steel. These valves offer strong sealing performance, can withstand extreme conditions such as high temperature and high pressure, and have a long service life. Therefore, hard-seal ball valves are suitable for applications requiring high temperature, high pressure, strong corrosion, and high viscosity.
The advantages of hard-seal ball valves are strong sealing performance, good corrosion resistance, and long service life, making them particularly suitable for harsh environments such as high pressure and high temperature. However, these ball valves require more sophisticated mechanisms, resulting in higher manufacturing and maintenance costs.
Soft-seal structures use a flexible material, primarily flexible plastics, such as PTFE or polytetrafluoroethylene, as the sealing material between the valve and seat. These ball valves offer good sealing performance and easy operation, and are widely used in fluid control under general operating conditions.
Soft-seal ball valves offer advantages such as strong sealing, good anti-leakage performance, and easier opening and closing; however, they are relatively less corrosion-resistant.
In general, hard-seal and soft-seal ball valves each have their own characteristics, and the choice should be made based on actual needs and the operating environment.