摘要 |
Equipment, process and techniques are shown for rehabilitating old underground pipelines, particularly asbestos pipelines, in which an old underground pipeline is replaced, as by drawing a bursting head through the old pipe to burst it and simultaneously pulling a new pipe through behind the bursting head. The invention has particular applicability to the rehabilitation of old asbestos pipelines in which the burst up debris must be contained or encapsulated in some manner. The macro-encapsulation materials shown form an in-situ layer of a temporarily fluid macro-encapsulating material which absorbs and immobilizes asbestos fibers and pipe fragments, the macro-encapsulating material being applied simultaneously as the pipe bursting operation proceeds. |