600MPa grade-and-more high-strength building steel bar and duct piece application method thereof

Abstract

The invention discloses a 600MPa grade-and-more high-strength building steel bar and a duct piece application method thereof. The high-strength steel bar comprises 0.32-0.7wt% of C, 0.5-1.2wt% of Ni, 0.3-2.1wt% of Cr, 0.6-1.3wt% of Si, 0.4-0.8wt% of Mn, 0.6-0.7wt% of Cr, 0.12-0.28wt% of Mo, 0.3-0.55wt% of Ni, 0.2-0.3wt% of V, below 0.05wt% of S, below 0.02wt% of P, and the balance Fe. A production method of the high-strength steel bar comprises the following steps: 1, sending a steel bar into a heating furnace, and heating; 2, carrying out preliminary hot rolling of the steel bar; 3, putting the above obtained cooled steel bar in a tempering heating furnace, and heating to 500-550DEG C; 4, carrying out high pressure injection of the obtained heat-insulated steel bar with water or a quenching liquid; and 5, carrying out examination warehousing. The high-strength steel bar has the advantages of strong bearing capacity, security improvement, reduction of the consumption of the steel bar, and cost reduction.

Description

technical field [0001] The invention relates to a manufacturing method and an application method of a steel bar, in particular to a high-strength building steel bar of 600 MPa and above and an application method thereof. Background technique [0002] At present, steel bars for construction are used as steel for concrete structures. Most of the ordinary steel bars are HRB335 and HRB400 steel, and a small amount of HRB500 steel is used. Although the above-mentioned ordinary steel bars are widely used in house construction in my country, especially buildings (houses) Due to the low yield strength of the steel bars, the steel bars of the face plate are subjected to artificial active loads during the construction process, and the upper steel bars of the double-layer two-way steel bars are often bent and deformed, which cannot meet the structural restrictions on the protective thickness of the reinforced concrete, resulting in cracks, resulting in engineering Potential quality probl...

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Problems solved by technology

[0002] At present, steel bars for construction are used as steel for concrete structures. Most of the ordinary steel bars are HRB335 and HRB400 steel, and a small amount of HRB500 steel is used. Although the above-mentioned ordinary steel bars are widely used in house construction in my country, especially buildings (houses) Due to the low yield strength of the steel bars, the steel bars of the face plate are subjected to artificial active loads during the construction process, and the upper steel bars of the double-layer two-way steel bars are often bent and deformed, which cannot meet the structural restrictions on the protective thickness of the reinforced concrete, resulting in cracks, resulting in engineering Potential quality problems, due to the low strength level of steel bars, often limited by factors such as iron burial depth, geological conditions, and subway space, the diameter of steel bars used is getting thicker and the spacing between bars is getting denser, which brings about The cost and the cost of concrete construction have risen, and there are disadvantages such as waste of steel, high cost, and difficulty in bending steel bars.