The standard control valve seat leakage rating control valve is an important part of flow and pressure control valves in pipelines and equipment. There are not only single seat, double seat, sleeve and other stop valve types of control valves, but also angle stroke automatic pneumatic ball valve and automatic butterfly valve for use with control valves. This type of control valve has a stronger flow capacity. The leakage level of the leakage valve of the control valve is an important performance parameter for acceptance of the use of the control valve. There are many misunderstandings about the definition and application of the leakage level of the control valve seat, which affect the correct selection of the control valve.

4. Investigate the flow condition upstream of the sensor and check the condition of the inner wall of the sensor measurement channel. The upstream flow condition of the sensor is often limited by the installation space and deviates from the specified requirements. For example, there is no straight pipe section of sufficient length close to the choke that generates turbulence, which will introduce factors affecting the accuracy of measurement. In particular, if the upstream of the proximity sensor is equipped with a regulating valve or a gate valve that is not fully opened, the only way to completely solve the problem is to change the installation position of the sensor; Install flow adjustment when the length of upstream straight pipe section is insufficient? quot; It can only be partially improved.