| 摘要 |
In the leak testing of pipelines such as buried natural gas pipelines or submarine oil pipelines, a low frequency oscillator (12) generates an acoustic wave with the liquid-filled pipeline (10) and the transit time for the wave to travel the pipeline length and return after reflection from the end of the section under test is measured to determine the average acoustic velocity in the liquid-filled pipeline. Hydrostatic pressure is monitored by means of a dead-weight tester (11), and changes in hydrostatic pressure correlated with acoustic velocity or with average pipeline temperature derived from the acoustic velocity. |
