Introduction to Domestic Oil Casing Production Lines
In recent years, China’s oil casing processing technology has continuously improved. The export volume of oil casings has also increased significantly, with many domestic manufacturers enhancing their production capabilities for oil casings. Through investigations and research on China’s oil casing processing enterprises, it has been found that the industry suffers from severe polarization. Small enterprises generally have rudimentary equipment and low levels of production line automation, resulting in high labor intensity for personnel, significant differences in product quality, and high scrap rates. In contrast, large enterprises primarily use imported equipment such as threading machines, hydrostatic testing machines, coupling machines, and packaging machines, with substantial investment and high levels of automation in their entire production lines.
For example, in 2007, the Engineering Installation Brigade of Shengli Oilfield Underground Operations introduced the first fully automated oil casing production line domestically acclaimed as first-class. Most of the main equipment was imported, achieving high levels of automation, including automatic control and conveyor line operations for multiple processes like material passageway, thread parameters, static hydraulic testing, mold marking, and spray printing.
By the end of 2007, the Tubing Production Line built by Tuha Oilfield Machinery Factory selected two LOC650-R high-precision horizontal machining centers manufactured by Japanese Okuma Corporation for the tubing threading machines. For the coupling processing production line, one VSC400DUO high-precision vertical machining center made by German EMAG GmbH was chosen, demonstrating world-class standards in high-tech content, precision, automation, and efficiency.
Shengli Oilfield Gaoyuan Company owns four oil casing production lines with an annual output of 150,000 tons of oil casings in grades PLS-2, P110, N80, and J55. Thread processing uses CNC lathes, and imported forming tools complete the processing in one go. They also purchased two high-precision CNC lathes from Japanese Mori Seiki Co., Ltd., capable of processing tubing larger than 7 inches.
In 2011, CNOOC Energy Development Pipeline Drilling Tubulars Branch established an oil casing production line capable of producing sizes ranging from 2 3/8 inches to 7 inches, with an annual capacity of 10,000 tons. It can process proprietary gas-tight connections, quick-connect couplings, and standard API threads. The lathes mainly used were high-precision SUC8128A lathes manufactured by Shenyang No.1 Machine Tool Plant, designed based on Belgian models, featuring three-axis linkage and automatic centering of chucks. The entire production line has a high level of automation and uses advanced UV spray painting equipment domestically, allowing painted seamless tubes to dry in one second, improving product efficiency and appearance while also considering environmental protection.