| 摘要 |
<p>The method involves connecting a permanent direct current voltage to an electric conductor (4). Another conductor (5) guided helically parallel to the former conductor is earthed and a current flow is measured or displayed. The current flow is occurred with discharge of a medium flowing in the plastic pipe lines or with breakdown of the outer piper of the pipe line between both the conductors. An independent claim is also included for an arrangement for monitoring leakages in underground plastic pipes, particularly in plastic pipes passing trenchless in the ground.</p> |
