Production Process of Hot-rolled Steel Strip for Petroleum Casing Pipe

J55 oil casing pipe is a kind of tubing used as the material of petroleum well wall for a long time. It is connected to thousands of kilometers of pipe string through special thread. In the downhole cementing process, it is mainly affected by the external squeeze force, internal pressure and axial tensile load. The oil casing string is completed by perforation method. It also withstands high-temperature, high-energy instantaneous impact loads from perforation blasting.

After analyzing the use of petroleum casing and the inductive judgment of its primary failure mode, petroleum casing manufacturers believe that the performance of the casing should be high strength, high resistance, high crush resistance and high thread joint strength. The advantages of straight seam welding sleeves are uniform wall thickness, high accuracy of a few inches, crush resistance against crushing is 10% ~ 1.5% higher than that of seamless pipes of the same steel type, low carbon content of materials, no breakage after perforation, and cheap price.

The production process of hot rolled steel strip for J55 petroleum casing is: molten iron-based magnesium desulfurization, top-bottom re-blow converter, alloying, LF essence, calcium feeding line, soft blowing, medium wide conventional grid slab continuous casting, slab cutting Open a heating furnace, rough rolling 5 times rolling, heat preservation, finishing rolling 7 times, controlled rolling laminar flow cooling, coil and take one package.

According to the use of J55 petroleum casing steel strip, considering its strength, plasticity, resistance and weldability, it is difficult to improve the strength of J55 grade steel strip with low carbon high manganese steel strip, but the plasticity and resistance are better. Under the conditions of controlled rolling and cooling, it is feasible to use the existing skills to produce hot-rolled strip steel for J55 oil casing. Currently,has the ability to produce in batches.