With the increasing degree of reform and opening up, the valve market has become a huge fat. In the past, many state-owned valve manufacturers faced the crisis of shutdown due to the impact of their own physique. Although many enterprises have achieved greater results through effective reform, many enterprises have come to an end. This provides a huge development space for the valve market of private enterprises. Due to the short history and weak technical force of private enterprises, they can only carry out simple imitative production, and produce low-end extensive valves, which has caused the unreasonable phenomenon that China's valve market is difficult to export and cheap to export. 　　

Fault 4: The actuator motor heats rapidly, vibrates and crawls, and stops moving in a short time. Treatment method: measure whether the input terminal of control module is disturbed by AC with AC 2V voltage; Check whether the signal line is isolated from the power line; Whether the potentiometer and its wiring are in good condition; Whether the feedback component acts normally.