| 摘要 |
<p>A method of lining installed pipework which includes the steps of taking a length of liner pipe made from a memory retaining plastics material of external diameter greater than the internal diameter of the pipework to be lined, drawing the liner pipe through a swaging die which is attached directly or indirectly to the pipe to be lined using pulling means under tension attached to the leading end of the liner pipe and threaded through the pipework to reduce the external diameter of the liner pipe by up to 15%, the tension applied by the pulling means being such as partially to restrain the radial expansion of the outer surface of the liner pipe after its emergence from the die, drawing the liner pipe after its emergence from the die, drawing the liner pipe through the installed pipework with its outer diameter reduced to and/or maintained at a dimension less than that of the inner diameter of the pipework and thereafter allowing the liner pipe to expand within the pipework by relaxation of the said tension followed by memory induced expansion at ordinary atmospheric pressure and at the ambient temperature of the pipework.</p> |
