Determination of yield point and yield strength of Mn content of nm500 steel

At the same time of doing well in Mn content of NM500 steel production and operation, Yunnan company focused on completing the four phases of technical transformation construction projects, realizing industrial upgrading, improving equipment level, and laying a good foundation for the future development of the company. In the Mn content of NM500 steel technological transformation project, pollution control facilities have been built synchronously, and a large number of comprehensive utilization projects, such as comprehensive sewage treatment and recycling project, blast furnace gas waste heat and residual pressure power generation, have been invested and constructed.

Oxygen (O) is a harmful element in steel such as Mn content of NM500 steel. Although manganese, silicon, iron and aluminum are added to deoxidize the steel at the end of steelmaking, they can not be removed completely. During the solidification of molten steel, the reaction of oxygen and carbon in the solution will produce carbon monoxide, which can cause bubbles. Oxygen mainly exists in the form of FeO, MnO, SiO2, Al2O3 and other inclusions in the steel, which reduces the strength and plasticity of the steel. Especially, it has serious influence on fatigue strength and impact toughness.

The riser is an indispensable equipment in the development of offshore oil and gas resources, mainly for drilling, conducting liquid, conducting mud and transporting oil and gas. Because steel catenary risers face complex service conditions such as surges, seabed clay, and ice loads, they need to have high fatigue strength, large plastic deformation capacity, and excellent fracture toughness. At present, China's first self-developed and designed 6-inch steel catenary riser was successfully laid on August 18 this year in the first deep-water self-operated large gas field Lingshui 17-2 project.

The purpose of complete annealing of Mn content of NM500 steel, wear-resistant plate is to improve the bad structure, such as coarse grain, widmanstatten structure (coarse ferrite with directional growth along with coarse grain) or banded structure caused by high temperature during hot forging, hot rolling, welding or casting of steel plate, so as to refine grain, improve mechanical properties, and reduce stress and hardness.