ASTM A53 seamless steel pipe accounts for a large proportion of all steel pipes, but the actual production of seamless steel pipe is often used to control rolling and cooling technology. Because of the uneven defects of the cooling plate, it is easy to control the cooling process, seriously affecting product quality and contract cash. The plate edge wave is a serious one.


The wave shape defect on the side of seamless steel tube is caused by non-uniform transverse cooling. On-site tracking shows that there are obvious zonal supercooling zones on both sides of the side wave plate. The transverse cooling caused by non-uniform factors is as follows:


1) There is a transverse temperature difference between the center and the side of the seamless tube.


2) There is a large temperature difference between the middle and the edge of seamless steel tube in the process of controlled rolling.
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3) The finishing mill adopts "CVC" rolling process, which is caused by the difference between the two sides and the middle extension of the steel plate, which results in the internal stress of the steel plate not reaching the bilateral level. Wave shape. But it will increase further in the subsequent cooling process.
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4) In the process of controlling the cooling process of seamless steel tube, not only the structure changes with the change of temperature, but also the complex stress changes occur.