| 摘要 |
According to the present invention there is provided an apparatus for forming a plug in a passsageway, the apparatus comprising a carrier ( 3 ) which in use is lowered into the passageway, the carrier being dimensioned to define a clearance between the carrier and the passageway; a body of material supported on the carrier, said material having a melting point which is higher than the temperature within the passageway at the point at which the plug is to be formed and which expands as it solidifies; and means ( 10, 11 ) for melting the body of material such that melted material flows into the clearance defined between the carrier and the passageway. |
