1 curtain plate, rails, lintels, reel and other parts of the surface is not allowed to crack, pressure pit and the more obvious convex, hammer marks, burrs, holes and other defects.
2 relative movement in the cutting, bending, drilling and other processing, must clean up the burr.
3 components or parts of the assembly, splicing does not allow dislocation.
4 welding should be solid, the appearance of flat, not allowed to slag, leakage welding and so on.
5 parts of the leakage surface, must be anti-rust treatment, the coating, the coating should be uniform, not the phenomenon of stripping.
6 all fasteners must be tight, not allowed to loose phenomenon.

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