Establish Of High Accuracy Air Flow Standard Facility

Gas flow meter is one of measuring instruments included in the nationalcompulsory verification catalog. As energy issues become increasingly prominent, themeasurement of gas trade is important, especially high accuracy gas flow meter iseven more obvious. In order to calibrate high accuracy gas flow meter, there is anurgent need to establish high accuracy gas flow standard facility to solve the problemof traceability.This article describes a high accuracy gas flow standard facility, including theprimary standard test rig and secondary standard test rig. The primary standard test rigis bell prover gas flow standard facility which used to test the critical nozzles flowrateless than65m3/h, the secondary test rig is the critical nozzle gas flow standard facilitywhich used to calibrate the high accuracy gas flow meter.This paper introduces the design principle and plan of standard facility, a newmethod of traceability is implied by use of a group of small nozzles to expand theflowrate. The main parameters of test rig and test results is introduced, evaluates theuncertainty of test rig, the test rig is also compare with PTB Germany and NMINetherlands, the uncertainty of the standard facility is validated.A measuring and controlling system is designed for meter under test for differentsignals output. The test program of upper machine, developed under Delphi, realizeshuman-computer interaction, data storage, process and display. The lower machine,through PLC, controls blowers and valves. data acquisition of temperature andpressure use field-bus communication. LAN communication protocol enables thecommunication between upper and lower machine. The test results show that thestandard facility has friendly interface and fully automated operation.