CONTAMINANT ACCUMULATION EFFECT ON GAS ULTRASONIC FLOW METERS Class # 1340

摘要

The following paper discusses the effects of accumulation on natural gas ultrasonic meters.The paper uses four meters,two Daniel meters and two Instromet meters,that were recalibrated at the CEESI Iowa facility.From CEESI's experience with recalibrations of contaminated meters,the results of these four meters are typical.Due to the relative newness of the other brands of meters in the US market,CEESI does not have recalibration data available for this paper and thus other brands are not included.The four meters discussed in the paper are labeled meters A through D.Meters A and B are Instromet Q3 meters.Meter A is an 8"meter and B is a 10"meter.Meters C and D are Daniel SeniorSonic meters.Meter C is a 10"meter and D is a 12"meter.As with most cleaning and recalibration projects,the process was not as simple as collecting as found data,cleaning,and then recalibrating.The data includes changing a transducer on the C meter and changing the whole set of transducers on the D meter.The data also includes the effects of debris in front of the flow conditioner on the B meter.Graph 1 illustrates the as found results for all four meters.The data shows that meters A and B over-registered by approximately 0.5% to 0.8% while meters C and D under-registered by about 0.2% to 0.5%.These results are typical.The contamination in the meters was similar and typical to contamination regularly observed on recalibration projects.The contamination could be described as light,uniform buildup,with material buildup,either totally covering or partially covering the flow conditioner and transducer faces.