前言在过程控制中,经常遇到生产物料的流量控制问题,因而涉及到传输管道和调节阀的选择,二者的选择是否恰当将直接影响产量和控制效果。比如管道过细或阀的口径过小,则起不到应有的调节作用,系统不能正常工作,若阀口径过大,阀经常工作在小开度下,则调节精度低,影响系统性能。在纸 Preface In process control, flow control problems often occur in the production of materials, which involves the choice of transmission lines and control valves. The proper choice of both will directly affect the yield and control effectiveness. For example, if the pipe is too small or the diameter of the valve is too small, it will not function properly and the system will not work normally. If the valve diameter is too large, the valve will often work under a small opening, which will affect system performance. In paper