Causes and Solutions for Internal Leakage in Forged Steel Ball Valves

The operation of a forged steel ball valve involves the rotation of the stem to open or close the valve. This type of valve is characterized by its light switch, compact size, and adaptability to large calibers. It offers excellent sealing performance, simple structure, and easy maintenance. The sealing surface and spherical surface are consistently in a closed state, minimizing erosion by the medium. Despite its widespread use across various industries, issues like internal leakage can pose challenges during field installation and debugging. In this discussion, we aim to explore common causes and provide solutions for the internal leakage in forged steel ball valves, offering valuable insights for maintenance personnel.

Causes and Solutions for Internal Leakage in Forged Steel Ball Valves:

1. Inaccurate Zero Position Setting of the Actuator:

Cause: The actuator's zero position setting is not accurate, failing to reach the valve's full closing position.
Solution: Manually close the valve, force a manual closure, screw back half a turn in the opening direction, and adjust the limit.

2. Travel Mode Selection for Forged Steel Ball Valves:

Cause: The valve's 90-degree rotation for self-opening and closing may result in insufficient torque force from the actuator, especially under pressure, preventing full closure.
Solution: Replace the actuator with higher thrust or use a balanced spool to reduce unbalanced forces from the medium.

3. Internal Leakage Due to Manufacturing Quality:

Cause: Inadequate control in the assembly process, leading to defects in sealing surfaces such as pitting and trachoma, causing internal leakage.
Solution: Rework the sealing surfaces to address manufacturing defects.

4. Debugging Issues of Forged Steel Ball Valves:

Cause: Challenges in manual opening after closure, difficulties in switching between action positions, and issues with the over-torque switch protection action.
Solution: Readjust the limit during the manual electric regulator's shaking, preventing damage to the deceleration transmission mechanism.

5. Cavitation Corrosion from Wrong Valve Selection:

Cause: Incorrect selection of forged steel ball valves leading to cavitation corrosion due to pressure differentials.
Solution: Choose a reasonable electric regulating valve based on specific technical requirements for different applications and system processes.

In conclusion, addressing these causes and implementing the suggested solutions can effectively mitigate internal leakage issues in forged steel ball valves, ensuring their reliable and efficient performance.