How to identify fake and shoddy steel product in appearance

1. Shoddy steel product is prone to folding. Folding is a variety of fold lines formed on the surface of the steel, and this defect often runs through the longitudinal direction of the entire product. The reason for the folding is that the counterfeit and inferior manufacturers pursue high efficiency, and the reduction is too large, resulting in ears. Folding will occur in the next rolling process. The folded product will crack after bending, and the strength of the steel will drop greatly. the
2. The surface of fake and inferior steel often has pockmarks. A pockmarked surface is a defect of irregular unevenness on the surface of the steel due to severe wear of the rolling groove. Because manufacturers of fake and inferior steel products want to pursue profits, it often happens that groove rolling exceeds the standard. the
3. Shoddy steel surface is prone to scarring. There are two reasons: a. The material of fake and inferior steel is uneven and has many impurities. b. The guides and guards of fake and inferior material manufacturers are poorly equipped and easy to stick to steel. These impurities are easy to cause scarring after biting the roll. the
4. Cracks are easy to occur on the surface of fake and inferior materials. The reason is that it blank is in Adobe, and adobe has many pores. During the cooling process, the adobe is subjected to thermal stress and cracks occur. After rolling, there are cracks. the
5. Fake and inferior steel is easy to scratch because the manufacturers of fake and inferior materials have poor equipment, which is easy to produce burrs and scratch the surface of the steel. Deep scratches reduce the strength of the steel. the
6. False and inferior steel has no metallic luster and is light red or similar in color to pig iron. There are two reasons: a. Its billet is adobe. b. The rolling temperature of counterfeit and inferior materials is not standard. Their steel temperature is measured visually, so that rolling cannot be carried out according to the specified austenite region, and the performance of the steel cannot meet the standard naturally. the
7. The horizontal ribs of fake and inferior steel are thin and low, and the phenomenon of insufficient filling often occurs. The reason is that to achieve a large negative tolerance, the reduction in the first few passes of the finished product is too large, the iron shape is too small, and the passing shape is not full. the
8. The cross-section of fake and inferior steel is elliptical. The reason is that to save materials, the reduction amount of the first two passes of the finished roll is too large. The strength of this rebar is greatly reduced, and it does not meet the standard of rebar shape. the
9. The composition of high-quality steel is uniform, the tonnage of the cold shear is high, and the end face of the cutting head is smooth and neat. However, due to the poor material quality of fake and inferior materials, the end face of the cutting head often has the phenomenon of meat loss, that is, unevenness and no metallic luster. Moreover, because the products of fake and inferior material manufacturers have fewer heads, big ears will appear at the head and tail. the
10. The material of fake and inferior steel contains many impurities, the density of the steel is relatively small, and the size is seriously out of tolerance, so it can be weighed and checked without a vernier caliper. For example, for rebar 20, the national standard stipulates that the maximum negative tolerance is 5%, and its single theoretical weight is 120 kg when the length is 9M, and its minimum weight should be: 120 X (l-5%) = 114 kg, The actual weight of a single piece weighed out is less than 114 kg, which is a fake and inferior steel because its negative tolerance exceeds 5%. Generally speaking, the effect of whole-phase weighing will be better, mainly considering the problem of cumulative error and probability theory. the
11. The inner diameter of fake and inferior steel fluctuates greatly because of; a. The steel temperature is unstable and has negative and positive sides. b. The composition of the steel is uneven. c. Due to poor equipment and low foundation strength, the rolling mill has a large bounce. There will be a large change in the inner diameter within the same week, and such steel bars are prone to fracture due to uneven stress. the
12. The trademark and printing of high-quality materials are more standardized. the
13. For large threads with a steel material diameter of 16 or more, the distance between the two trademarks is more than 1M. The
14. The longitudinal reinforcement of fake and inferior steel rebar is often wavy. the
15. Since the fake and inferior steel manufacturers do not have driving vehicles, they pack loosely. The sides are oval.