BS ISO 23493:2020 pdf free

BS ISO 23493:2020 pdf free.Welding and allied processes一Process specification for laser -arc hybrid welding for metallic materials
Generally, the single pass penetration that can be achieved by the laser-arc hybrid welding process is significantly greater than that achieved by electric arc welding, depending on factors such as the laser parameters used, welding speed, welding position, etc. Furthermore, the gap-bridging tolerance of the process is less than that of arc welding. As such, the groove type and size for this process should be designed taking both the penetration capability and gap-bridging tolerance of the laser in to account, e.g. butt joint grooves with significantly broader root faces can be welded, albeit close-fitting, square-edged root preparations are then needed.
The special groove types have been proved to be useful in application.
The grooved types are based on ISO 9692-1 for steels and ISO 9692-3 for aluminium and aluminium alloys. It is possible, and sometimes with advantage for steel sructures, to use filler materials with lower strength because of the high cooling rates and reduced width of the laser-arc hybrid weld seams.
The butt joint preparations for laser-arc hybrid welding are recommended in Table 2 (for single side welding) and Table 3 (for double side welding). The fillet and flange joint preparations for laser-arc hybrid welding are recommended in Table 4.
The butt joint grooves can be prepared by a mechanical process (machining) or high precision cutting process (e.g. laser cutting or waterjet cutting), provided that a dimensional accuracy suitable for the limited gap bridging tolerance of the hybrid welding process can be insured. As a guide, a maximum butt joint gap tolerance is of the order of5 % to 10 % of material (or, in thicker materials, root face) thickness, depending on factors such as the material being welded, welding position and resulting weld quality required.
In order to avoid defects like porosity and slag inclusions, the groove and its immediate surroundings should be cleaned (as specified in the WPS) before welding, ensuring removal of any rust, oxide film or mill scale, contamination by oils, machining fluids and any other organic materials, and burrs brought
about during joint preparation.BS ISO 23493 pdf download.