What is the height and width of the welding seam of the African rural lighting ready board that should be flat and free of virtual welding?

Technical parameters for welding seams of rural lighting ready board bodies in Africa (sheet metal corner welds, suitable for Eskom rural projects)

The conventional thickness of the panel for the ready board of rural lighting in Africa is 1.2-1.5mm cold-rolled steel plate, with carbon dioxide gas shielded welding corner joints. The welds are smooth, free of virtual welding, slag inclusion, porosity, cracks, and undercutting.

Weld leg height K (fillet weld leg): 1.5-2.0 mm, minimum not less than 1.5 mm, not greater than the thickness of the plate, to ensure the strength of the box structure, resistance to vibration, and resistance to salt spray environment cracking.

Weld seam width: 3-4 mm, uniform width of weld seam, fluctuation of weld seam width within the same section ≤ 0.5 mm.

Weld seam excess height (weld seam height above the surface of the base metal): 0.5-1.5 mm. It is not allowed to protrude too high, which is convenient for subsequent polishing and spraying. Excessive excess height can easily lead to stress concentration and cracking during long-term outdoor use; It is not allowed to have a depression lower than the plane of the base material.

Mandatory requirements for appearance and defects

It is strictly prohibited to have virtual welding, leakage welding, incomplete fusion, or welding penetration; The depth of undercutting is ≤ 0.3mm, and the length of local undercutting does not exceed 10% of the total length of the weld seam.

Clean up welding slag splashes after welding; Continuous welds at corners, intermittent welds with a single segment length of ≥ 8-10 mm and a segment spacing of ≤ 15 mm, ensure the overall stiffness of the box and adapt to harsh outdoor conditions in rural Africa (high temperature, salt spray, dust).

Additional notes

If the thickness of the African rural lighting ready board body is increased to 2.0mm, the height of the welding legs should be adjusted to 2.0-2.5mm, and the width of the weld seam should be 4-5 mm. The size of the welding legs should not be greater than the thickness of the thinner base material to avoid burning through the box body sheet metal.

During the acceptance of the Eskom project, in addition to the size of the welds, the key inspection is to ensure that the welding is smooth and polished without sharp edges and corners, to ensure the integrity of the spray paint film, and to prevent preferential corrosion and failure of the weld position.

Practical inspection: Use a weld gauge to check the height of the weld leg and excess height; Visually inspect the continuity of the weld seam, eliminate virtual welding, and conduct tapping and spot checks on the firmness of the weld seam after welding.