Causes & Solutions of Internal Leakage of Forged Ball Valves
The forged steel ball valve is operated, opened or closed by rotating the stem. The ball valve is light in switch and small in size, and it can be made into one with a large caliber. The sealing performance is good. It is simple in structure and convenient for maintenance. The sealing surface and spherical surface is often in the closed state. It is not easy to be eroded by the medium. It has been widely used in various industries. However, there are also some problems bothering the field installation and debugging personnel in the process of using, such as the internal leakage problem. Here we want to discuss the common causes and solutions for the internal leakage of forged steel ball valves. Hope it will help the maintenance person.
Causes and solutions of internal leakage of the forged steel ball valve
I.The zero position setting of the actuator of forged steel ball valves is not accurate and does not reach the full closing position of the valve.
Measures of Adjustment:
1. Manually close the valve (we must confirm that it has been completely closed.).
2. Then, force to manually close the valve.
3. Screw back (the opening direction of valves) half a turn.
4. Then, adjust the limit.
II.The selection of the travel mode of forged steel ball valves
The valve is rotated 90 degrees to open and close itself. The torque force of the actuator is not large enough. When there is no pressure, the debugging is easy to reach the full close. When there is a rotating force, it cannot overcome the thrust pushed by the liquid. Therefore, the close is not in place.
Solution: replace the actuator with a large thrust, or replace it with a balanced spool to reduce the medium unbalance force.
III.Internal leakage caused by the manufacturing quality of the forged steel ball valve
The assembly process control is not strict in the production process of the valve material and processing technology, resulting in that the grinding unqualified of sealing surfaces, pitting, trachoma and other defects of the product is not completely removed. It will result in the internal leakage of electric forged steel ball valves.
Solution: rework the sealing surface.
IV.The internal leakage caused by debugging problems of the forged steel ball valve
Affected by the processing and assembly process, the forged steel ball valve cannot be opened manually after closing, such as through the action position of the upper and lower limit. They need to switch to adjust the stroke of the electric regulating valve smaller. There is an unsatisfactory state that the electric regulating valve is not closed or the valve is not opened. If the stroke of the electric forged steel ball valve is adjusted larger, the over-torque switch protection action will be caused. If the action value of the over-torque switch is adjusted to be larger, there will be damage to the deceleration transmission mechanism, or even the motor will be burned. In order to solve this problem, the electric control valve will shake when debugging manual electric regulator. It will shake a circle towards the direction to open again, and we set the lower limit of the electric door switch position.
Solution: Readjust the limit.
V. The cavitation corrosion of the valve caused by the wrong selection of the forged steel ball valve causes the internal leakage of the electric regulating valve.
The cavitation is related to pressure difference. When the actual pressure differential valve delta P is greater than produce cavitation critical pressure differential delta Pc, the cavitation will be produced. In the process of cavitation bubbles, it releases enormous energy. The valve core has great damage on the throttling components. The valves are subjected to severe cavitation corrosion. The leakage of the valve seat can reach more than 30% of the rated flow rate, which cannot be made up. Therefore, different uses of electric forged steel ball valves have different specific technical requirements. In accordance with the system process, it is vital to choose a reasonable electric regulating valve.
The above mentioned are the causes and solutions of the internet leakage of forged steel ball valves. Hope it can help you.
Causes and solutions of internal leakage of the forged steel ball valve
I.The zero position setting of the actuator of forged steel ball valves is not accurate and does not reach the full closing position of the valve.
Measures of Adjustment:
1. Manually close the valve (we must confirm that it has been completely closed.).
2. Then, force to manually close the valve.
3. Screw back (the opening direction of valves) half a turn.
4. Then, adjust the limit.
II.The selection of the travel mode of forged steel ball valves
The valve is rotated 90 degrees to open and close itself. The torque force of the actuator is not large enough. When there is no pressure, the debugging is easy to reach the full close. When there is a rotating force, it cannot overcome the thrust pushed by the liquid. Therefore, the close is not in place.
Solution: replace the actuator with a large thrust, or replace it with a balanced spool to reduce the medium unbalance force.
III.Internal leakage caused by the manufacturing quality of the forged steel ball valve
The assembly process control is not strict in the production process of the valve material and processing technology, resulting in that the grinding unqualified of sealing surfaces, pitting, trachoma and other defects of the product is not completely removed. It will result in the internal leakage of electric forged steel ball valves.
Solution: rework the sealing surface.
IV.The internal leakage caused by debugging problems of the forged steel ball valve
Affected by the processing and assembly process, the forged steel ball valve cannot be opened manually after closing, such as through the action position of the upper and lower limit. They need to switch to adjust the stroke of the electric regulating valve smaller. There is an unsatisfactory state that the electric regulating valve is not closed or the valve is not opened. If the stroke of the electric forged steel ball valve is adjusted larger, the over-torque switch protection action will be caused. If the action value of the over-torque switch is adjusted to be larger, there will be damage to the deceleration transmission mechanism, or even the motor will be burned. In order to solve this problem, the electric control valve will shake when debugging manual electric regulator. It will shake a circle towards the direction to open again, and we set the lower limit of the electric door switch position.
Solution: Readjust the limit.
V. The cavitation corrosion of the valve caused by the wrong selection of the forged steel ball valve causes the internal leakage of the electric regulating valve.
The cavitation is related to pressure difference. When the actual pressure differential valve delta P is greater than produce cavitation critical pressure differential delta Pc, the cavitation will be produced. In the process of cavitation bubbles, it releases enormous energy. The valve core has great damage on the throttling components. The valves are subjected to severe cavitation corrosion. The leakage of the valve seat can reach more than 30% of the rated flow rate, which cannot be made up. Therefore, different uses of electric forged steel ball valves have different specific technical requirements. In accordance with the system process, it is vital to choose a reasonable electric regulating valve.
The above mentioned are the causes and solutions of the internet leakage of forged steel ball valves. Hope it can help you.
