| AVS 65th International Symposium & Exhibition | |
| Vacuum Technology Division | Tuesday Sessions |
| Session VT-TuP |
| Session: | Vacuum Technology Division - Poster Session |
| Presenter: | Kenta Arai, National Institute of Advanced Industrial Science and Technology (AIST), Japan |
| Authors: | K. Arai, National Institute of Advanced Industrial Science and Technology (AIST), Japan H. Yoshida, National Institute of Advanced Industrial Science and Technology (AIST), Japan |
| Correspondent: | Click to Email |
Recent years, a portable type sniffer leak detector plays an important role for searching leaks of refrigerant gases from air-coordinators to prevent the global warming. In general, a standard leak, from which a small continuous gas (order of sub-g/year to ten-g/year) flows out, is used to check the performance of the leak detector for a reliable leak test. For the purpose, there are two methods to check the detector. One is that a probe of the detector is moved in front of the standard leak (method A) and the other is that the probe and an exhaust of the standard leak are closed and almost touched (method B). For method A, several standards have been published, i.e., SAE J1627:2011 and its related standards, EN 14624:2012[1], and ANSI/ASHARHE 173-2013. In those standards, the prove velocity and the distance between the probe and the exhaust of the standard leak are given and for EN 14624, 20 mm/s and 3 mm, respectively. For method B, it is explained in a manual of several leak detectors. In this study, we have measured the response of the leak detector against the standard leak by those two methods and compared their results.
A sniffer leak detector in which a pump equipped is tested. For method A, the detector was set on an electric actuator and its probe was set to face an exhaust of a standard leak. The moving velocity of the electric actuator was changed from 5 mm/s to 40 mm/s and the distance between the probe and the standard leak changed from 1 mm to 20 mm. For method B, the velocity was set at 0 mm/s and the distance at 0 mm, respectively. Prior to the tests, the leak rate of the standard leak was calibrated to be 5 g/year by a pressure rise method [2].
Both at the beginning and at the end of the experiments, the response of the leak detector was obtained by method B. Between them, the response of the leak detector was obtained by method A. The detector output obtained by method B between two measurements was stabilized within 10 %. For method A, the detector output was decreased with an increase of both the probe velocity and the distance from the probe to the standard leak. Above both the probe velocity of 20 mm/s and the distance of 10 mm, the detector output was disappeared. The detector output obtained by method B was about 5 times as high as that obtained by method A with the velocity of 20 mm/s and the distance of 3 mm given in EN 14624. Thus, for the properly use of the sniffer leak detector, it is important to clear the conditions for its performance check.
[1] EN 14624:2012 Performance of portable leak detectors and of room monitors for halogenated refrigerants.
[2] Kenta ARAI et al., Metrologia 51 (2014) 522.