| 摘要 |
PURPOSE:To obtain an underwater welding device which has a small vapor phase area diameter and is capable of preventing the hardening caused by quenching of a weld, by providing additionally a flexible heat retaining and shielding material which is made to press-contact closely to a welding bead of high temperature and a base material face of its circumference, next to a welding device, when a welding work is executed, forming a vapor phase area in the water. CONSTITUTION:A supporting plate 6 is fitted in the rear of a conventional vapor phase area forming vessel 1, a clamping bolt 7 is inserted into a screw hole provided on the plate 6, a spring 8 is provided in the circumference of the bolt 7, and a heat retaining material fitting rack base 9 is fitted. Subsequently, shielding gas 2 is blown onto a weld line of a base material 4 together with welding gas from a welding nozzle 3, welding is executed, forming continuously a vapor phase area, and a welding bead 15 is formed. In this case, heat retaining materials 11, 12 having elasticity and heat resistance are fitted to the lower part of the rack base 9, and also a layer-like heat retaining material 13 having about 1-2mm. thickness is provided on the surface of the base material 4 around the weld line. According to said constitution, the head 15 and the base material part 4 of its vicinity do not contact directly with water of the outside, and it is possible to prevent generation of a convection by quenching caused by a convection of surrounding water. |
