Tham khảo tài liệu 'the welding of aluminum & its alloys part 5', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Welding design 75 Mitre fillet concave face reduced throat thickness if judged on leg length 45 equal leg length regular isosceles triangle Mitre convex concave and unequal leg length fillet. For the fillet weld the shape of the weld and the amount of penetration into the root will affect the throat thickness. The effective throat thickness is ti in Fig. . The size of the fillet weld must be determined by the designer and should be of sufficient size to carry the load. The throat may therefore be completely different from the material thickness. The fillet weld may also be described as a mitre a concave or a convex fillet. In addition the fillet weld may have unequal leg lengths. These four types of fillet weld are illustrated in Fig. . The butt weld The butt weld typical forms of which are illustrated in Fig. is a simple and easily designed joint which uses the minimum amount of material. Figure also includes definitions of some of the features of a weld preparation such as root face angle of bevel and included angle . Butt welds as illustrated in Fig. may also be classified as full penetration or partial penetration. With the conventional fusion welding processes of TIG and MIG penetration of weld metal into the surface of a flat plate from a bead-on-plate run is typically 3 mm and 6 mm respectively. To achieve a full penetration butt weld at thicknesses over these it is necessary for the two close square-butted edges to be bevelled although leaving a small gap between the edges will increase penetration. Typical weld preparations for the various processes will be found in the relevant process chapter. Butt joints may be single or double sided - if double sided it is often necessary to back-gouge or back-grind the first side to be welded to achieve a joint that is free of any lack of penetration. 76 The welding of aluminium and its alloys Single - V Double - V Single bevel Double - V Single - V Various forms of the butt weld. .
