Rebar should be free from surface oil stains, paint污, rust scale, and scale defects.
2. When descaling steel rebars, ensure that the surface rust and discoloration are thoroughly cleaned, but there's no need to specifically treat the rust and discoloration.
If severe rust, pitting, spots, or other phenomena are found on the steel bar surface during or after the descaling process, the damage should be assessed to determine whether to downgrade for use or discard it.
3. The surface of the rebar is allowed to have a small amount of rust, but the area should be less than 5% of the total surface area.
Rebar surfaces should not have defects caused by dents, blemishes, deformation, or hammering marks.
Rebar surfaces must be free of oil, dust, and other residues.