The causes for pits in seamless steel pipes (SMLS pipe) may be as follows:
1. Perforation equipment issues
Some manufacturers choose unreasonable equipment for the piercing furnace. A shorter piercing furnace prevents the round steel from being heated evenly, resulting in high internal and external temperature deviations, affecting structural changes, resulting in pitting and pitting.
2. Head setting problem
Some manufacturers use inferior plugs. The water sprayed from the plugs directly contacts the internal and external surfaces of the high-temperature steel pipes. The steel pipes encounter large temperature differences, resulting in internal and external defects, such as warping or pits.
3. Perforation temperature problem
Some manufacturers are unable to adjust the temperature adaptability of seamless pipes of different steel grades in a timely manner, thereby changing the surface and internal structure of the steel grades, causing warping and pitting.
4. Pickling problem
Seamless steel pipes need to go through a pickling process. If the pickling time is not controlled properly, it can easily cause over-acid problems, which is also one of the reasons for surface pits.
5. Steel quality issues
The occurrence of pits in the steel pipe is related to the quality of the steel. If the steel has quality problems, such as uneven surface, cracks, etc., then it will be difficult to completely eliminate these defects no matter how perfect the subsequent treatment process is.
6. Construction environmental issues
The construction environment is also one of the important causes of pits in steel pipes. For example, environmental factors such as temperature, humidity, and dust at the construction site may affect the quality of steel pipes.
In order to avoid pits in seamless steel pipes, manufacturers need to strictly control every aspect of the production process to ensure that parameters such as perforation equipment, head settings, and perforation temperature are reasonable. At the same time, they must strengthen the control of the pickling process to ensure that the pickling time is appropriate. In addition, it is also necessary to select high-quality raw materials and improve the level of production technology to reduce the occurrence of pits on the surface of steel pipes. During the construction process, it is also necessary to pay attention to the control of the construction environment to avoid the impact of environmental factors on the quality of steel pipes.
Conclusion:
There are many reasons for pits in seamless steel pipes. It is necessary to strictly control all links during the production process and strengthen quality management and supervision to ensure that the quality and appearance of the steel pipes are at their best. At the same time, steel pipes also need to be inspected and maintained regularly during use, and potential problems can be discovered and dealt with in a timely manner to ensure the safety and service life of steel pipes.
Read more: ASTM Standard Seamless Pipe Quality Inspection or Schedule 40 VS. Schedule 80 Pipe
