What is the effect of valve body friction on the response speed of pneumatic control valves

In pneumatic control systems, pneumatic control valves are key components, and their performance is directly related to the operating efficiency of the entire system. Valve body friction is one of the important factors affecting the performance of pneumatic control valves, and has attracted widespread attention from domestic and foreign scholars in recent years.
Pneumatic control valves are widely used in pneumatic industrial manipulators, complex production and manufacturing assembly lines, and other fields. The main function is to adjust the air flow pressure, flow rate and flow direction in the pneumatic system to ensure the normal operation of pneumatic actuators or mechanisms. From a structural analysis, the pneumatic control valve consists of a valve body and a valve core, and the relative positions of the two realize the functions of normally closed and normally open. Valve body friction refers to the resistance generated when the valve body and the valve shaft contact during the opening and closing process. Its ratio to the normal pressure constitutes the friction coefficient, which usually ranges from 0.05 to 0.1. The specific value is affected by many factors such as valve material, sealing surface shape, sealing material and lubrication status.
The influence of valve body friction on the response speed of pneumatic control valves is mainly reflected in the following aspects:
First, increase the action delay. When the friction of the valve body increases, the opening and closing of the valve needs to overcome greater resistance, resulting in delayed action. In pneumatic control systems, response speed is one of the key factors that determine system performance, especially in situations where rapid cutting is required. Increased friction may result in failure to meet the demand for rapid response.
Secondly, positioning accuracy is impaired. The positioning control performance of pneumatic control valves is significantly affected by friction. When friction increases, the positioning accuracy of the valve core may decrease, causing a deviation between the control signal and the actual action, thereby affecting the stability and accuracy of the system.
Thirdly, energy consumption increases. In order to overcome the friction of the valve body, the pneumatic control system needs to provide more energy, which not only increases energy consumption, but also may have an adverse effect on the service life of the pneumatic actuator. Especially in continuous control systems, the increase in energy consumption caused by valve body friction is particularly obvious.
Finally, system reliability is reduced. Excessive friction of the valve body may cause problems such as valve jamming or increased wear during long-term operation, thereby affecting the reliability and stability of the system. Especially under harsh working conditions, the influence of valve body friction is more prominent.
In order to reduce the influence of valve body friction on the response speed of pneumatic control valves, the following measures can be taken:
First, reasonable material selection. Choose materials with low friction coefficient and excellent wear resistance to make valves and valve shafts to reduce friction.
Second, improve processing accuracy. Improve the processing accuracy of the sealing surface and reduce the surface roughness, thereby reducing the friction coefficient.
Third, choose suitable sealing materials. Choose appropriate sealing materials according to specific applications to achieve a balance between low friction and high sealing performance.
Fourth, proper lubrication. Add a proper amount of lubricating oil during the opening and closing of the valve to reduce friction, but the amount of lubricating oil must be controlled to avoid excessive leakage.