Unqualified steel is easy to fold
Folds are various creases formed on the surface of steel, and this defect often runs through the entire product longitudinally. The reason for the folding is that in order to pursue high efficiency, the counterfeit and inferior manufacturers have a large amount of down pressure, which will cause ears and folds during down rolling. The folded product will crack after bending, and the steel strength is low. decrease very much

Unqualified steel usually has a pitted appearance.
The pitted surface is a defect caused by the irregular and uneven surface of the steel caused by severe wear of the rolling groove. In order to pursue profits, fake and inferior steel manufacturers often over-roll grooves most often.

Unqualified steel is easy to scar the surface
There are two reasons: a. The material of inferior steel is uneven and there are many impurities. b. The guides and guards of manufacturers of inferior materials are poorly equipped and are easy to stick to steel. After these impurities bite, the rolls are prone to scars.

Unqualified steel surface cracking
This is because it is made of adobe, which has many pores, and the adobe cracks due to thermal stress during cooling, and cracks after rolling.

Unqualified steel is easy to scratch
The reason is that unqualified steel manufacturers have poor equipment and are prone to burrs that scratch the surface of the steel. Deep scratches reduce the strength of the steel.

Unqualified steel has no metallic luster and is light red or similar in color to pig iron
There are two reasons for this: a. It is made of adobe. b. The rolling temperature of inferior steel is not standard. The temperature of their steel is visually measured, and they cannot be rolled in the required austenite zone, and the performance of the steel will naturally not meet the standard.

The horizontal bars of unqualified steel are thin and low, and often appear unfilled
The reason is that in order to achieve a large negative tolerance, the finished product has a large amount of pressing in the first few passes, the iron shape is small, and the hole position is not filled.

Unqualified steel cross-section is oval
The reason for this is that in order to save material, the manufacturer has a large amount of reduction in the first two passes of the finished roll. The strength of the steel bar is greatly reduced, and it does not meet the steel bar shape and size standards.
The quality of the steel is uniform, the tonnage of the cold shear is high, the end surface of the shear head is smooth and tidy, while the crudely made material is poor, and the end surface of the shear head often has broken ends, that is, uneven meat, and no metallic luster. And because the products of manufacturers of fake and inferior materials have fewer heads, big ears will appear at the head and tail.
Unqualified steel has many impurities, low density and out-of-tolerance dimensions, so it can be verified by weighing without a vernier caliper. For example, No. 20 rebar, the national standard stipulates that the maximum negative tolerance is 5%, and the theoretical weight of a single rebar at 9M is 120kg.
If the actual weight of a single piece is less than 114 kg, it is inferior steel, because the negative tolerance exceeds 5%. In general, the full-phase trade-off is better, mainly the cumulative error and probability theory of the problem.

The inner diameter of unqualified steel fluctuates greatly
The reason for this is; the lake. The temperature of the yin and yang steel is unstable. 2. The composition of the steel is uneven. 3. The equipment is simple, the strength of the foundation is low, and the rebound of the mill is large. The inner diameter of the same week will have a large change, so that the steel is prone to fracture due to uneven stress.
The trademark and printing of high-quality materials are more standardized.
For large threads with a diameter of 16 or more, the distance between the two trademarks is more than IM.
The longitudinal bars of inferior steel bars are often wavy.
The counterfeit steel builders are looser in their packaging because they don't have a linear drive. The sides are oval.