Pitting corrosion and pits are common surface quality problems in seamless pipe(astm a53 pipe) manufacturing. When delivering pits and potholes, if this happens, many seamless steel pipe mills will say that the quality problems of the original steel mills have caused this problem. The choice of round steel may have an impact on seamless pipe manufacturing, but it is not the final deciding factor. The real reason lies in this process-perforation.
Many seamless steel pipe plants have unreasonable selection of equipment for piercing furnaces. The short perforation furnace prevents the round steel from being evenly heated, resulting in large internal and external temperature deviations, affecting structural changes, and causing the setting of pits and pit plugs. Generally, inferior plugs are used in seamless steel pipe factories. The water sprayed from the plug directly touches the inner and outer surfaces of the high-temperature steel pipe, and the steel pipe encounters a large temperature difference, thereby forming internal and external defects, that is, warping or pits.
In the perforation furnace equipment, small factories do not pay attention to environmental protection and temperature control. For seamless pipes of different steel grades, they cannot adjust the temperature adaptability in time, which in turn changes the surface and internal structure of the steel grades, causing the phenomenon of skin warping and pitting.
For seamless pipes, attention should be paid to the selection of perforation furnace equipment. Excellent equipment can avoid pits in the production of seamless pipes, speed up production, and reduce a certain delivery period. The longer perforation furnace makes the round steel evenly heated, and the internal and external temperature deviation is small. Secondly, a plug is used. Although the cost is high, the perforated capillary has no warpage and pits, which eliminates the surface quality problems that may be encountered in subsequent processing from the source.
Many seamless steel pipe plants have unreasonable selection of equipment for piercing furnaces. The short perforation furnace prevents the round steel from being evenly heated, resulting in large internal and external temperature deviations, affecting structural changes, and causing the setting of pits and pit plugs. Generally, inferior plugs are used in seamless steel pipe factories. The water sprayed from the plug directly touches the inner and outer surfaces of the high-temperature steel pipe, and the steel pipe encounters a large temperature difference, thereby forming internal and external defects, that is, warping or pits.
In the perforation furnace equipment, small factories do not pay attention to environmental protection and temperature control. For seamless pipes of different steel grades, they cannot adjust the temperature adaptability in time, which in turn changes the surface and internal structure of the steel grades, causing the phenomenon of skin warping and pitting.
For seamless pipes, attention should be paid to the selection of perforation furnace equipment. Excellent equipment can avoid pits in the production of seamless pipes, speed up production, and reduce a certain delivery period. The longer perforation furnace makes the round steel evenly heated, and the internal and external temperature deviation is small. Secondly, a plug is used. Although the cost is high, the perforated capillary has no warpage and pits, which eliminates the surface quality problems that may be encountered in subsequent processing from the source.
