2 When assembling, the H-steel is welded without an assembled frame, resulting in a deviation in the height of the H-shaped steel, and the web is off-center; after the wing webs are butted, the welds are not leveled and there are obvious bumps; the light steel webs are uneven, Not rectified before assembly.
3 Welding In terms of welding, light steel welding H-shaped steel wing plates are spliced after cutting, and the welding seam is not equipped with an arc-igniting plate, resulting in insufficient welding seams, pits on the edges and not fusion, etc., which are not flush with the base material; The size of the welding foot of the leg and the corbel is smaller than the design drawing, the corner of the fillet weld is serious, the arc is generally lower than the base metal, and there are many pores; the weld formed by CO2 welding is poorly formed, the width is inconsistent, and the height is inconsistent. Large and small; manual welding seam is not straight, the width is different, the undercut phenomenon is serious; the welding slag splash is not cleaned.
4 Drilling In terms of drilling, the drawings were not reviewed well beforehand. In the place where the single row of holes should be opened, a double row of holes was opened. As a result, the holes were left on the component without repairing. For example, the H-shaped steel at the junction of the column and the corbel is a double-row hole, and the H-shaped steel of the same specification as the main beam and the secondary beam is a single-row hole, but when the holes are opened, double-row holes are opened, which affects the strength and appearance quality after installation.
5 Final assembly process During the final assembly process, the joint between the steel column corbel and the H-shaped steel beam was misaligned up and down, left and right, and the size was not well controlled.
6 Rust removal and paint rust removal and paint: rust removal is sloppy, does not meet the grade requirements, the paint will return rust and peel off soon; the thickness of the paint film is uneven, and the thickness of the sun surface is generally super thick, up to 250μm, but the shade is often 90μm Around (the thickness of the indoor paint film is specified as 125μm); the impurities are not cleaned up before painting, there are many dirt, unevenness, and the sagging phenomenon is common.
7 Component transportation and storage In the process of component transportation and stacking, no placed parts are stacked flat. Instead, they are unloaded at will, stacked in disorder, or even buried in muddy ditch, causing component deformation, bumps and pollution.
8 Components leaving the factory When the components leave the factory, the centerline markings of the steel columns and steel beams are not marked, which is quite common, which brings difficulties to the installation and construction correction detection.
9 Wing web splicing The splicing length of the wing web does not meet the requirements. If the splicing length of the wing plate should not be less than 2 times the width of the wing plate, the splicing welds of the flange plate and the web should be staggered by more than 200mm, and the splicing length of the web should not be less than 600mm. However, the above requirements are often not met in practice.