Development Of Cold-drawing Oil Pipe With J55 Steel Grade

At present, a large number of domestically produced oil pipes have been used in domestic petroleum industry besides special-purpose and high-strength tubing, more than 80% pipes are produced by our country. The main way of production for oil pipe is hot-rolling and cold-drawing. Our plant adopted the way of cold-drawing to produce oil pipe because of funds. On the basis of the investigation of domestic oil pipe production situation, the seamless tube of the cold-drawing production process and the production technology were researched. The multi-drawing technology was used mostly in the cold-drawing oil pipe, but this way has many shortcomings such as high production costs, low productivity, heavy environmental pollution etc, so the technology of once-cold-drawing was proposed to produce tubing. On the basis of the equipment level and the production situation, we explored the new production technology. The piercing and cold-drawing principles were studied, and the technical requirement that the J55 cold-drawing seamless steel pipe was used for API oil pipe for supply was introduced, by once-drawing as the starting point, strict checks at all quality control points. Through a large number of experiments and exploration, the production technology of the seamless steel tube of our plant is to become mature. By adjusting the piercer to control the quality of the rough pipe strictly, to ensure the rough pipe dimension precision and the quality of the pipe surface. The pickling process has been optimized, from the temperature to the concentration of sulfuric acid. The sequence of the pickling technology has been explored. So it formed a perfect pickling process. According to API requirements, the changes in size of the drawing process was tracked, determined the best match model parameters. Through the trial-produce to confirm the correct heat treatment process and enable the pipe to meet the various requirements of API with good mechanical properties. Through the final inspection, the oil pipes of our plant are better than that of the various indicators of API requirement to fully meet user needs. Results show that, the once-cold-drawing technology to produce oil pipe in our plant is entirely feasible, with good economic and social benefits.