2. Straight-stroke cylinder actuator The piston sealing ring of the straight-stroke cylinder actuator (including the actuator used for fork-type angular stroke) leaks air (cylinder leaks air), the piston cylinder head seals air, the stop screw sealing assembly leaks air, and the seal between the output shaft and the cylinder head leaks air.
3. Double rack angular travel actuator The piston rear sealing ring of the double rack angular travel actuator leaks air, the cylinder head and the cylinder block sealing ring leak air, the upper and lower support sealing rings connected with the output shaft and the cylinder block leak air, and the limit screw on the cylinder head leaks air.
4. External accessories External accessories, such as the output pipeline joints of various positioners, have leaks, such as pneumatic speed increasers or relays, quick release valves, one-way governors and position retaining valves.
5. If there is no strict switching time limit for valves, pneumatic accessories and process joints should be reduced as much as possible, such as canceling quick release valves, pneumatic speed increasers, one-way governors, pressure reducers and bending heads.
6. Regularly clean and add lubricating oil, keep the push rod and valve stem clean and free from rust, the chrome-plated layer is peeled off, and the lubrication is sufficient to ensure that the seal is not worn and does not leak oil.
7. During inspection, check whether the exhaust port of pneumatic diaphragm actuator (the positive exhaust port is on the lower diaphragm cover and the negative exhaust port is on the upper diaphragm cover) and the exhaust port of single-acting piston cylinder are leaking, and repair them in time if there is any leakage. The above is the treatment method of air leakage of control valve actuator. Air leakage will cause the vibration of the control valve and affect the normal work. Please pay attention to the inspection during normal use.