Poor quality of billet: The front end of the billet is cut with too much inclination, too much curvature, and the centering hole of the billet is not straight, which can easily cause uneven wall thickness of the steel pipe head; if the billet itself has internal defects or uneven composition, it will also affect the uniformity and accuracy of the pipe thickness.
Material substitution: If materials that do not meet the API 5L L360 standard are used incorrectly in production, the thickness and performance of the pipe will not meet the standard.
Processing process problems
Rolling parameter errors: If the roll speed is too high, the elongation coefficient is too large, and the rolling is unstable, the wall thickness of the pipe will not meet the standard.
Mold and equipment failure: Mold wear, deformation, or reduced equipment accuracy cannot guarantee accurate control of pipe thickness.
Measurement and inspection problems
Measurement error: Inaccurate measuring tools, improper measuring methods, or irregular operation of measuring personnel may cause the measurement results to be inconsistent with the actual thickness.
Inspection omissions: There is a lack of strict inspection links in the production process, and pipes that do not meet the thickness standards are not discovered in time.
Solution
Control the quality of raw materials: strengthen the inspection of tube billets to ensure that they meet the material requirements of API 5L L360, check the dimensional accuracy and appearance quality of tube billets, and avoid using defective tube billets.
Optimize processing technology: According to the specifications and requirements of the pipes, reasonably adjust the rolling parameters to ensure the stability of the rolling process; regularly maintain and maintain the molds and equipment, and replace worn molds and parts in time.
Improve the accuracy of measurement and inspection: use measuring tools with accuracy that meets the requirements, adopt the correct measurement methods, and train measurement personnel; strengthen the inspection during the production process, increase the inspection frequency, and conduct strict sampling inspection on finished pipes.
