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Steel pipe if you have the six kinds of circumstances, may be false and inferior steel pipe

1. The steel tube is easy to appear fold. Folding is formed on the surface of the pipe line, this kind of defect often throughout the entire product longitudinal. Causes of fold is due to the pursuit of the false and inferior, high efficiency, large reduction, handle, when the next rolling produce folding, folding products will be cracking after bending, steel strength decreased.

2. Steel tube appearance often have pitted surface phenomenon. Pits was caused by worn groove of steel tube surface is irregular uneven defects. Because want to pursuit of profit and inferior steel pipe manufacturer, often appear groove rolling the overweight.

3. The steel pipe surface are prone to scarring. For two reasons: 1. The uneven and inferior steel pipe materials, impurities. 2. And inferior material manufacturer guide equipment simple, easy to stick steel, these impurities after the roll bite are prone to scarring.

4. The material surface cracks easily, because its billet is adobe, adobe air, adobe in the process of cooling due to the effect of thermal stress, cracks, after rolling there is crack.

5. Steel tube is easy to scratch, the reason is false and inferior material manufacturer equipment simple, easy to produce burr, scratch steel pipe surface. Deep scratches to reduce the strength of the steel pipe.

6. Steel pipe without metallic luster, reddish or similar to the color of the pig iron, two point two, its billet is adobe reasons. 2, and inferior material rolling temperature is not standard, their steel temperature is through visual inspection, so can't austenitic area of the rolling by the regulation, the performance of the steel tube nature is not up to standard.

More about square tube manufacturers in tianjin, tianjin DaQiuZhuang thin-walled steel tube, DaQiuZhuang Q235 steel pipe and other detailed information, please pay attention to our website of tianjin yu da steel trade!

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	Contact：Manager wang Phone：15822998178 銷售一部：022-59598306 銷售一部：022-59598305 銷售一部：022-68277670 銷售一部：022-68587183 銷售一部：022-59515660 銷售二部：022-59512993 銷售二部：022-59512992 address：Jing wang fruits of DaQiuZhuang Town JinHai street on the west side 200 meters

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