| 摘要 |
<p>A method is provided for temporarily or permanently blocking the bore of a gas service pipe 5. In the method a resilient ball 6 is forced along the pipe 5 from the gas meter tap end of the pipe 5 by gas pressure, the ball 6 forming a force fit sufficient to resist any attempt to dislodge it by the pressure of gas in the pipe 5. The ball 6 is forced to a position where it is outside the gas consumer's premises 1.</p> |
