To increase the efficiency of testing piped natural gas ultrasonic flowmeter

a study on on-line inspection of piped natural gas ultrasonic flowmeter is conducted based on comparison of sound velocity.Theoretical foundation and procedures of speed of sound comparison testing method are illustrated.The sound velocity calculation model is established.According to the testing procedures and field situation

software and hardware of an ultrasonic flowmeter on-line testing system has been established based on sound velocity comparison method.This testing program is developed by using platform C#.This device connects to the flow computer through ethernet

read out quantity of flow synchronously and measures speed of sound

pressure

temperature

signal gain

signal to noise ratio and other parameters

calculates the theoretical sound velocity through the internal core software

combined with database to judge the eligibility of parameters.The test result shows that the successful developed system has friendly interface

easy to operate

and can load temperature

pressure

composition and other key parameters steadily.The calculation relative error less than 0.2 %

and the repeatability of test results prior to 0.05 %.