Analysis Of Affecting Factors For The Accuracy Of Orifice Flowmeter

The orifice flowmeter has the following advantages:technological maturity,stable and reliable,easy to operate and Easy to check.It's widely used in the natural gas metering handover and trade settlement.In the large amount of natural gas trade,every percentage error of the measurement results will be amplified very much.Avoid every little error means to redeem huge economic losses.In the time of the orifice flowmeter's operation,the measurement error will increase with the various influencing factors.This dissertation mainly analyzes some influence factor of orifice flowmeter's error,analyzes the influence mechanism and influence level.Through the formula analysis of the operation effect of various parts of the orifice flow meter,computer modeling and CFD of the orifice flowmeter,definite the common problems and the countermeasures of orifice flowmeter.The main content as follows:The sharpness of the ridge at the right angle inlet is required very high-accuracy,once worn,results in large measurement errors,which can not be accurately eliminated by modifying the correlation coefficient.So when it worn,replace it in time.Pressure transmitter,differential pressure transmitter,if there is a problem with the pressure parts,or the signal wire has signal attenuation,will cause a large error in the measurement results,so timely check them and make sure the scene display value and remote display value accuracy.Wet natural gas can lead to a variety of problems and error,this requiring the removal of water molecules as much as possible before orifice flowmeter.Measurement of the roughness of the inner wall of the pipe will result in measurement errors,which can not be eliminated by the correction coefficient of roughness when the roughness increases to a certain degree,and the measuring pipe should be replaced as far as possible.