In orifice meter measurement system, the fluid flow through the throttle device on the pipe orifice plate will be in place before and after the differential pressure, the differential pressure and the size of the fluid flow is related. In the actual operation, such as air, gas, steam metering, because the measured medium is water vapor, so when the temperature or reduce pressure increases to a certain degree of them is water vapor into water, and is often collected before measuring the orifice plate, will give orifice meter caused great error, so, in the process of operation must pay attention to the water before the orifice the degree of influence on the measured results, the timely processing. First, to timely condensate in the drain line. Install the drainage device to avoid water pipeline, the main measures, to have reasonable design pipe slope and the distribution of drainage device, and scheduled maintenance check, avoid gathered a lot of water wall tube. When the condensate also reduces the pipeline in humidity, slow down the condensate pipe corrosion and other impurities, so as to improve the accuracy of measurement data. Water, solve the throttling parts before the most simple way is at the bottom of the throttling parts infusion holes. Throttling device installed in a vertical process pipe, or switch to segmental orifice or eccentric orifice. Uncertainty of eccentric orifice plate is small, is better than that of segmental orifice. Might also be interested in metal rotameter.