Here we take a look at what some of the methods to identify fake steel:
1. Shoddy steel prone to folding. Folding is formed on the surface of a variety of steel fold, this defect often throughout the product vertical. The reason is due to shoddy manufacturers of folding the pursuit of high efficiency, reduction is too large, resulting in the ears, it creates a rolling when folded down, it will crack when folded products bending, the strength of steel big drop.
2. Steel is often shoddy appearance Pock phenomenon. Pock is caused due to a serious groove worn steel surface uneven irregular defects. Because of shoddy steel manufacturers have to pursue profits rolling groove most often exceeded.
3. Shoddy steel surface is easy to produce scarring. There are two reasons: 1. Uneven shoddy steel materials, impurities. 2. Shoddy material manufacturers guides poorly equipped, easy to stick steel, easy to produce scarring after the roll bite of these impurities.
4. Shoddy material surface easy to crack because it is blank adobe, adobe many pores, adobe in the cooling process due to thermal stress, cracks, after rolling there cracks.
5. Shoddy steel easily scratched because shoddy material equipment is very easy to produce burrs, scratches steel surface. Deep scratches reduce the strength of steel.
6. No shoddy steel metallic luster, pale red color of pig iron or similar, there are two two reasons, it is adobe blank. 2, shoddy-rolling temperature is not standard, they are visually steel temperature, so the region can not be prescribed by the austenite rolling, natural properties of steel can not be reached.
7. Transverse reinforcement steel thin shoddy low, often sufficient dissatisfaction phenomenon, because manufacturers to achieve large negative tolerance, finished in front of a few larger reduction, iron-type small, hole filling dissatisfaction.
8. Shoddy magnetism stainless steel oval cross-section, because the manufacturers in order to save material, the first two tracks finished roll reduction is too large, the strength of this steel is greatly decreased, and does not conform to the standard dimensions of rebar.
9. Uniform quality steel components, high tonnage cold shears, cut the first end surface smooth and tidy, but due to poor material shoddy material, there are often cut off the meat first end face of the phenomenon, namely uneven, and no metallic sheen. And because of shoddy little head cut wood product manufacturers, end to end will be a big ears.
10. Shoddy steel material containing impurities, the density of steel is small, and size tolerance serious, so in the absence of a vernier caliper case, you can check it weighed. For example, for steel 20 national standards set forth in the most negative tolerance of 5%, while its length 9M single theoretical weight of 120 kg, its minimal weight should be: 120X (l-5%) = 114 kg, weigh out the actual weight of a single smaller than 114 kg, it is shoddy steel, because it is more than 5% negative tolerance. Generally the whole amount commensurate would be better, mainly taking into account the cumulative error and probability theory problem.
11. Diameter size shoddy steel fluctuations due; l, steel surface temperature instability of yin and yang. 2, the non-uniform composition of the steel. 3, due to poor equipment, low-intensity ground, rolling big bounce. There will be changes in the larger inner diameter of the same week, so easy to produce steel discontinuity break.
12. Trademarks and printing high-quality materials are relatively standardized.
13. Three steel 16 or larger diameter screw spacing between the two trademarks are over IM.
14. Inferior longitudinal reinforcement steel rebar often wavy.
15. Shoddy steel manufacturers because there is no traffic, so the package is relatively loose. Side of the oval.
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