Processing method of high yield ratio and high plasticity steel product for prestressed concrete

Abstract

The invention relates to a processing method of a steel product for a prestressed concrete, in particular to a processing method of a high yield ratio and high plasticity steel product for the prestressed concrete. The processing method comprises the following steps of: firstly, smelting and rolling the following chemical components in percentage by weight into a wire rod or straight rod with or without screw threads by a steel mill: one ore more micro-alloy elements such as 0.10 to 0.5 percent of C, 0.3 to 1.8 percent of Si, 0.6 to 1.9 percent of Mn, 0.02 to 0.2 percent of Nb, 0.01 to 0.1 percent of V, 0.01 to 0.2 percent of Ni, 0.1 to 0.5 percent of Cr, 0.015 to 0.2 percent of Ti and 0.001 to 0.005 percent of B, and the balance of Fe; secondly, heating the rolled threaded wire rod or straight rod to a temperature of between 850 and 1,100 DEG C in a heating furnace, cooling the rolled threaded wire rod or straight rod to a temperature of between 600 and 690 DEG C in a cooling device, quenching the rolled threaded wire rod or straight rod in a quencher for 5 to 30 seconds by using water or quenching liquid, and heating the rolled threaded wire rod or straight rod to a temperature of between 450 and 650 DEG C in a tempering heating furnace for tempering; thirdly, cooking the rolled threaded wire rod or straight rod to normal temperature through a tempering cooling device; and finally, performing inspection and warehousing. According to the processing method, hydrochloric acid or sulfuric acid is not used for acid cleaning and phosphatization, so the processing method has the advantage of environment friendliness; besides, the processing method can ensure that the product has the advantages of high elongation percentage, obvious yield point elongation and high yield ratio.

Description

technical field [0001] The invention relates to a method for processing steel for concrete, in particular to a method for processing steel for high-strength yield ratio and high plasticity prestressed concrete. Background technique [0002] At present, the prestressed concrete steel produced at home and abroad has been widely used in the construction field, and it can improve the overall strength of concrete and reduce the development of cracks in reinforced concrete structural engineering. However, the elongation of most prestressed steels at home and abroad is only 3-6%, and the strength-to-yield ratio is only between 1.05-1.15. The tensile value of prestressed steel is generally designed at 70% of the tensile strength. When the plasticity and yield are relatively small, the overall reinforced concrete structure is under the impact of external forces such as earthquake horizontal forces, and there is no safety reserve for prestressed steel. Instantaneous fracture occurs, ...

AI Technical Summary

Problems solved by technology

In this way, a large amount of waste acid produced by the existing process cannot be effectively treated, and there is serious environmental pollution; moreover, multiple high-power wire drawing machines are used for continuous drawing, which also seriously wastes limited electric energy resources.

Therefore, the existing processing method of steel strand for prestressed concrete has shortcomings such as serious environmental pollution, waste of electric energy and steel resources, high production cost, etc., and needs to be improved.

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