The structure and dimensions of the welded beam are shown in the figure. The material is Q235, and the maximum length of the steel plate is 2500mm. Try to determine the connection position of 1, web plate and wing plate 2, and each bar. 1, the steel plate assembly shall be subjected to cutting stress relief before centering (semi-automatic cutting machine can be used for flame stress relief of the web wing plate without cutting).

2. Choose the combination of manual welding and CO2 gas shielded welding to locate the arc manually. J422 and H08A are both acceptable.

3. Single K groove on the web. Fillet weld.

4, it is best to double beam construction at the same time, back to back. 2. Welders should butt weld at the same time. Select the back welding method. After welding a small grid, reverse welding the reverse side, and then welding the root. Pay attention to the interlayer temperature.