What are the key maintenance points for valve actuators in industrial automation?

Maintenance of valve  actuators  in industrial automation is crucial for ensuring their proper operation, extending service life, and maintaining the stability of the entire industrial system. Below are some key maintenance points:
Routine maintenance
Visual Inspection: Regularly inspect the appearance of the valve Actuator for any dust, oil stains, corrosion, or mechanical damage. Clean surface dirt promptly to maintain the Actuator's cleanliness, ensuring easy observation of its operational status and timely detection of potential issues.
Connection inspection: Check whether bolts, nuts, and other fasteners at the connections between the Actuator and valves, pipelines, and electrical components are loose. Ensure secure connections to prevent issues such as leakage, transmission failure, or poor electrical contact caused by looseness. For flanged connections, also inspect whether the gaskets are damaged and replace them promptly if necessary.
Operation Status Monitoring: Observe whether the actuator's movements are smooth and steady during operation, and check for any abnormal noises, vibrations, or jamming. Additionally, ensure the actuator's opening indication matches the actual valve position and that the signals from the control system are functioning properly. If any abnormalities are detected, promptly shut down the system for inspection.
regular maintenance
Lubrication and maintenance: Regularly lubricate the transmission components according to the type of actuator and the requirements of the user manual. Suitable lubricating oil or grease is generally applied or injected to parts such as gears, bearings, and screws to reduce friction, wear, and ensure transmission efficiency and flexibility. But be careful to avoid lubricating oil contaminating valves or other equipment.
Seal inspection and replacement: Check the seals of the actuator, such as sealing rings, packing, etc., for aging, wear, deformation, or leakage. For seals with leaks, they should be replaced in a timely manner to ensure the sealing of the actuator and prevent medium leakage from causing damage to the environment and equipment. At the same time, when replacing seals, it is important to ensure proper installation to avoid additional damage to the seals.
Electrical system inspection: Inspect the electrical system of the actuator, including motors, controllers, sensors, cables, etc. Check whether the insulation resistance of the motor meets the requirements to prevent short circuit or leakage of electricity. Clean the dust on the surface of the controller and sensor, check if their connections are loose, and ensure accurate signal transmission. In addition, check whether the cables are damaged, aged, etc. If there are any problems, replace the cables in a timely manner to avoid electrical faults.
Limit switch and protection device testing: Test the limit switch and other protection devices of the actuator to ensure their accurate and reliable operation. Limit switches are used to limit the travel of valves and prevent them from opening or closing excessively. By manually operating the actuator, check whether the limit switch operates accurately at the set position, and adjust it promptly if there is any deviation. At the same time, test other protective devices such as overload protection, overheating protection, etc. to ensure that the actuator can automatically stop running in abnormal situations and avoid equipment damage.
 
Special situation maintenance
 
Media impact treatment: If industrial media is corrosive, viscous, or contains impurities, it may have adverse effects on valve actuators. For actuators that come into contact with corrosive media, corrosion-resistant materials should be selected or measures such as anti-corrosion coatings should be taken. For viscous media or media containing impurities, it is necessary to regularly clean the surface and interior of the actuator to prevent the accumulation of media that may affect the normal operation of the actuator. For example, in some chemical production, it is necessary to regularly acid or alkali wash the actuator to remove surface corrosion products or adhered media.
Dealing with extreme environmental conditions: Valve actuators used in extreme environmental conditions such as high temperature, low temperature, humidity, and high dust require corresponding protective measures. In high-temperature environments, the actuator should be insulated to prevent damage to the motor and electronic components due to overheating; In low-temperature environments, insulation measures should be taken to prevent the lubricating oil of the actuator from freezing or the seals from becoming hard or brittle. For humid environments, moisture-proof measures should be taken to prevent electrical components from being affected by moisture and short circuiting; For dusty environments, it is necessary to regularly clean the heat dissipation holes and ventilation openings of the actuator to prevent dust from blocking and affecting heat dissipation and normal operation.
 
Valve actuators of different types and brands may have differences in maintenance details, so it is important to refer to the equipment's user manual and Detsen manufacturer's recommendations during maintenance to develop a reasonable maintenance plan and measures to ensure the reliable operation of the  actuator.