Inspection of steel bars and inspection of steel bar joint process

When inspecting steel bars, first check the brand and quality certificate of the steel bars; secondly, check the appearance. Take 5% of the steel bars from each batch. Check that there are no cracks, scars, delamination, etc. on the surface. The bulge on the surface of the steel bars shall not exceed the horizontal limit. The rib height, defect depth and height shall not be greater than the allowable deviation of the part. The bending degree of each meter of steel bars shall not be greater than four meters. The next step is to conduct mechanical property tests. If each batch is less than 60 tons, take 2 bars from each batch, cut into two sections, and conduct tensile and cold bending tests respectively. When cutting the test piece, 100-500MM should be cut from both ends of the steel bar. When the test piece is greater than 60 tons, the corresponding steel bar must be cut. If a test result does not meet the requirements, double the number of samples should be taken from the same batch for each test. If there is still one unqualified sample, the batch of steel bars is judged to be unqualified. When hot-rolled steel bars have brittle fracture, poor welding performance or obvious abnormal mechanical properties during processing, special inspections such as chemical composition analysis should be carried out.