Prone to collapse and shoddy steel. Fold is formed on the surface of a variety of steel flange line, which runs through the entire product defects are often vertical. Have folded because of shoddy manufacturers high efficiency, large reduction, resulting in sub-ears, rolling on the next have folded, folded products will crack after bending, the strength of steel fell.
Frequent appearance of inferior steel surface phenomenon Ma. Ma rolling groove surface wear due to serious anomalies arising from the uneven surface of steel deficiencies. Inferior to steel manufacturers as a result of the pursuit of profit, often rolling over the rolling groove.
Easy to produce inferior steel surface scarring. There are two reasons: 1. Inhomogeneous materials and shoddy steel products, and more impurities. 2. Materials and shoddy equipment manufacturers guide simple, easy to stick steel, these impurities after roll bite scar easily.
Inferior surface cracks easily because it is the blank adobe, adobe porosity, and adobe in the process of cooling due to the role of thermal stress, resulting in cracks, the crack there after rolling.
Inferior steel scratches easily, because the poorly equipped and inferior materials manufacturers, easy to produce burr, scratch the surface of steel. Depth of scratches reduced the strength of steel.
Non-metallic luster and shoddy steel, cast iron or similar red color, due to 2.2, which is adobe blank. 2, inferior materials rolling temperature non-standard, their steel temperature is visual, so that can not be required to carry out rolling of the austenite region, the properties of steel can not be achieved naturally.
Transverse steel reinforcement and inferior thin and low, are often dissatisfied with the phenomenon of charge, because the big manufacturers to achieve a negative tolerance, finished before the reduction of several large, iron-type small, hole filling dissatisfaction.
Inferior surface of steel oval-shaped cross section, the reasons for the factory owners in order to save materials and finished products of the two pre-roll reduction too, the strength of steel decreased significantly, but does not conform to the standard size rebar.
Uniform composition of high-quality steel, cold high tonnage shear, cut the first face smooth and tidy, and the material as a result of poor materials and shoddy, often there will be cut off the first face of the phenomenon of meat, that is rugged and non-metallic luster. Manufacturers as a result of inferior materials and cut the first few products, end to end will be a great handle.
Inferior steel material containing impurities, and the density of small steel and super-size difference a serious problem, the vernier caliper in the absence of circumstances, it can be weighed to check it. For example, the rebar 20, the national standards set forth in the most negative tolerance of 5% of its length when 9M single theoretical weight of 120 kilograms, its minimum weight should be: 120 X (l-5%) = 114 kilograms , weighing out the actual weight of a single 114 kilograms more than the small, it is inferior steel, because it exceeds the tolerance of negative 5%. Generally commensurate with the volume of the whole will be better, mainly taking into account the accumulated error and the probability of the problem.
Size of the diameter of inferior steel volatile because; l, there are yin and yang steel surface temperature instability. 2, non-uniform composition of steel. 3, due to inadequate facilities, ground-based low-intensity, large bouncing mill. There will be changes in the same week a larger diameter, so that even the reinforced fracture easily.
High-quality printing materials are trademarks and fairly standard.
Three steel diameter of more than 16 threads, the distance between the two trade marks are more than IM.
And inferior longitudinal steel rebar reinforcement often wavy.
The absence of inferior steel flange manufacturers lane, so relatively loosely packed. Oval-shaped side.
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