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Hi, this is the Industrial Control Assistant. For newly designed and installed control systems, in order to ensure that the control valves function properly during startup and to maintain the safe operation of the system, it is necessary to first check whether the markings on the valve nameplates meet the design requirements before installing the valves. At the same time, the following items should also be debugged. Basic error limit ； Total journey deviation ； hysteresis ； dead zone ； Leakage amount (performed in applications with strict requirements). If the control valve is undergoing major repairs in the original system, in addition to verifying the items mentioned above, it is also necessary to check the sealing performance of areas such as the packing gland and connections of the old valve. On-site, in many cases it is not due to quality issues with the valves themselves, but rather to improper installation or use of them, such as an inappropriate installation environment, incorrect location or orientation, or dirty pipelines. Therefore, the following aspects should be taken into consideration when installing and using electric control valves: (1) Control valves are field instruments; the ambient temperature should be between –25 and 60°C, with a relative humidity of ≤95%. If installed in an outdoor area or in high-temperature environments, waterproofing and cooling measures should be taken. Stay away from the epicenter or enhance seismic protection measures in areas where there is an epicenter. (2) Control valves should be installed vertically; in special cases, they can be tilted. If the tilt angle is large or the valve’s own weight is significant, a protective device should be installed on the valve support. (3) Do not install the control valves on the pipeline at a height above the ground or too high from it; when the pipeline height exceeds 2 meters, a platform should be provided as much as possible to facilitate the operation of the handwheel and maintenance. (4) Before installing the control valve, the pipeline should be cleaned to remove dirt and slag. After installation, to ensure that no impurities remain inside the valve, it is also necessary to clean the valve again, that is, to open all the valves using the medium, in order to prevent impurities from sticking. The handwheel mechanism should be returned to its original neutral position after use. (5) To enable production to continue in the event of a failure or maintenance of the control valve, bypass pipeline control valves should be added. At the same time, special attention must be paid to ensuring that the installation location of the control valve meets the process requirements. (6) The electrical part of the electric control valve shall be installed in accordance with the structural requirements for relevant electrical equipment. For example, whether explosion-proof products should be installed in accordance with the requirements of the \"Code for Installation of Electrical Equipment in Explosive Atmospheres\". At the same time, do not damage or scratch the explosion-proof surface during removal, and restore it to its original explosion-proof condition during maintenance. (7) After repairing the reducer of the actuator, attention should be paid to lubrication; low-speed motors generally do not require flushing or refilling with oil. After assembly, it is also necessary to check whether the valve position matches the indication of the open position.