摘要 |
The sheet material (2,4,30) to be welded is supplied by a feeder (16,18). The welder (36) has a welding head (24) which can assume a welding position; an intermediate position in which the welding head has a first pre-set distance (y) from the welding position; and a non-operating position in which the head occupies a second pre-set position (x) from the welding position, greater than the first distance. A movable heat shield is placed between the welding head and the sheeting. |