| 摘要 |
For hot-welding of roofing material, use is made of a carriage 1 which carries a liquefied petroleum gas drum 16 and a burner 10. The carriage also carries a reel 31 of welding strip 32. The carriage also has a chamber 40 which is open towards the roofing material and through which the strip 32 runs. The liquefied petroleum gas burner is a so-called hot gas burner which, at its outlet, delivers a hot gas flow consisting of the exhaust gases of the liquefied petroleum gas flame and cooled by a secondary air flow 19. The hot gas 19 thereby produced is introduced into the chamber 40 which is open towards the substrate and adjoins the latter via a defined gap 45 so that the hot gas 19 acquires a predetermined distribution and dwell time in contact with the weld seam area for optimizing the welding procedure. Both the method and the apparatus for carrying out the method are claimed. <IMAGE> |
