| 摘要 |
In a method for joining two pre-insulated pipes (1, 2) by bridging the gap between their insulating jackets with a jointing sleeve (6) and injecting insulating material (4a), such as foam plastic, in the space between the protruding ends (not shown) of the inner, medium-carrying pipes, a jointing sleeve (6) of transparent material is used. This makes it possible, without the use of special sensing equipment, such as ultrasonic sensing apparatus, to detect visually any faults (13) in the form of bubbles or voids that may occur in the insulating material (4a), and to repair such faults by drilling holes (14) through the jointing sleeve (6) into the faults (13) and filling the latter with insulating material through the holes. Seals may be provided between the ends of the jointing sleeve (6) and the outside of the two pre-insulated pipes (1, 2) by using narrow sleeves or rings (7, 8) of shrinkable material, that are inserted over one or both pipes (1, 2) before welding them together, and shrunk in place extending beyond the ends of the jointing sleeve (6). |
