在蒸汽测量中，蒸汽会出现两种状态，一种是过热蒸汽，还有一种是饱和蒸汽。过热蒸汽在输送的过程中，由于温度、压力的变化，特别是在过热度不高的情况下，会出现热量损失温度降低的状况，转换成饱和蒸汽状态，这样就导致了气压减小，而出现气体和液体混合的介质存在。
饱和蒸汽在输送的过程由于热量的损失很容易出现凝结的状态，而饱和蒸汽就成立液滴和液雾的双向流体。
在蒸汽测量的时候，为了减少蒸汽测量的误差，就必须保持蒸汽的过热度，这样就会减少蒸汽的含水量，加强管道的保温。采用蒸汽孔板流量计测量蒸汽时，在安装的时候必须进行检查，若安装不正确，将会导致蒸汽泄漏，无法正确计量，蒸汽流量计敷设的导压挂管必须要进行保温，不能安装在室外，否则会影响测量的结果误差。
由于蒸汽的特殊性质，若采用蒸汽孔板流量计测量，除了要注意以上几点外，还要根据蒸汽的特殊性质，改进蒸汽孔板流量计的不足之处，以适应蒸汽测量的要求，减少不必要的误差.
英文版本：
in the process of steam measurement, the steam will be two kinds of state, a superheated steam, there is a saturated steam. superheated steam in the transportation process, due to changes in temperature, pressure, especially in the superheat degree is not high, there will be heat loss temperature fall, into the saturated vapor state, this caused the pressure decreases, and the presence of gas and liquid mixed medium.
saturated steam in the conveying process due to heat loss is prone to condensed state, bidirectional fluid and saturated steam on the establishment of droplets and fog.
when the steam measurement, in order to reduce the error of measurement in steam, must maintain the superheat steam, steam will reduce moisture content, strengthen the pipe insulation. the measurement of steam steam orifice flowmeter, at the time of the installation must be checked, if not installed properly, will cause the leakage of steam, the steam flowmeter can not be measured correctly, laying the pressure guide tube must be hung for thermal insulation, can not be installed in the outdoor, otherwise it will affect the measuring result error.
because of the special nature of steam, the steam orifice plate flowmeter measurement, in addition to the attention of the above points, according to the special properties of steam, deficiencies steam orifice flowmeter, in order to adapt to the http:// steam measurement requirements, reduce unnecessary errors.