一、前言目前火电厂的汽水管道中均采用孔板或喷嘴等节流装置来测量管内流体的流量。节流装置虽有通用性强(能适用于绝大部份流体)、适应性高(能适用于几十毫米到几米直径的管道)、灵活性大(产生的差压值可以任意规定)的特点。但是由于制造的加工精度要求高,材料的要求也高,所以成本高。另外由于需用法兰夹紧,所以造成拆装困难、劳动强 First, the prelude At present, thermal power plant soda pipes are used orifice or nozzle throttling device to measure the flow of fluid in the tube. Although the throttle device versatility (can be applied to most of the fluid), high adaptability (applicable to tens of millimeters to a few meters in diameter pipe), flexibility (produced by the pressure value can be arbitrarily specified) Features. However, the manufacturing cost is high due to the high machining accuracy and high material requirements. In addition due to the need to use flange clamping, resulting in disassembly difficult, labor-intensive