INTER-LABORATORY TESTS IN AIR FLOW STANDARD |
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| Wen-Ti Lin, Jiunn-Haur Shaw, Hae Man Choi, Youn Kyun Oh |
- Abstract:
- A set of two laminar flow meters was used in 1998 as transfer standard for inter-laboratory tests in the range of l00 sccm ~ 1 slm on Brooks piston prover. Results were used for in-depth scrutinizing on the alignment of the vertical trigger mechanism and measuring volume, for possible leak checking and for improvements on secondary instruments of the piston prover at CMS. Further calibration, after such adjustment on the prover, shows an agreement of both sets of data within 0.2 %.
In 1999, an inter-laboratory test between CMS and KRlSS was conducted with the same set of laminar flow meters. Test results indicated a mean deviation no greater than 0.2 %, within the claimed measurement uncertainty. With the use of an Excel laser interferometer for piston stroke length measurement, repeatability of the piston traversing length is improved to 0.015 mm. Temperature measurements between inlet and outlet ports have agreement within 0.15 K with a temperature balancing helical tube installed upstream of the flow path. The pressure variation during the course of a piston stroke is maintained within 16 Pa after adjustment on the tapping location. Overall, an expanded measurement uncertainty of 0.15 % of reading can be achieved.
Subsequently internal tests of flow rates from 200 sccm to 12 slm were carried out among five different tubes with several mass flow meters. Comparison of test data in terms of mean error showed an agreement within 0.05 % ~ 0.1 % is achieved. - Keywords:
- inter-laboratory tests, laser interferometer, mass flow meter, piston prover
- Download:
- IMEKO-TC9-2000-086.pdf
- DOI:
- -
- Event details
- IMEKO TC:
- TC9
- Event name:
- FLOMEKO 2000
- Title:
- 10th Conference on Flow Measurement
- Place:
- Salvador, Bahia, BRAZIL
- Time:
- 04 June 2000 - 08 June 2000