Economic high-carbon wear resistant steel tube with excellent processing properties, and its production method

Abstract

An economic high-carbon wear resistant steel tube with excellent processing properties comprises 0.60-0.72wt% of C, 0.10-0.30wt% of Si, 0.50-1.20wt% of Mn, 0.0030-0.0070wt% of Ca, 0.60-0.86wt% of Cr, 0.015-0.050wt% of Als, 0.015wt% or less of P, and 0.005wt% or less of S. A production method of the steel tube comprises the steps of smelting, continuous casting for blank formation, cast blank slow cooling, cast blank heating, high pressure water de-scaling, hot rolling, front cooling, rolling, air cooling to room temperature, rear cover annealing, air cooling to room temperature, tube making, and induction heat treatment. The production method has the advantages of simple chemical elements, guaranteeing of the mechanical properties, and formation of uniform spherical pearlite structure at all positions of an annealed and rolled steel band, and online continuous induction heat treatment is adopted to make a steel material internally heated, so the heating speed is greatly higher than traditional heating speeds, the heat treatment speed per minute is improved, the heat insulation time can substantially decrease to 0.5-1min and is substantially shorter than traditional heat treatment heat insulation times, the growth tendency of austenite crystal grains is small, no decarburization occurs on surfaces, the production efficiency is improved, and the surface hardness is substantially improved.

Description

technical field [0001] The invention relates to a steel for construction machinery and a production method, in particular to an economical high-carbon wear-resistant steel pipe with excellent processing performance and a production method, and is especially suitable for manufacturing concrete delivery pipes and a production method. Background technique [0002] In the next ten years, with the advancement of urbanization, the amount of concrete machinery will increase, and the demand for concrete delivery pipes will increase as a consumable. At present, different construction machinery manufacturers use different concrete delivery pipe materials, among which steel materials are the main ones. With the development of concrete machinery, higher and higher requirements are put forward for the steel pipe wall thickness, weight, wear resistance and fatigue resistance. At present, the amount of stone transported by ordinary concrete steel pipes is about 15,000 to 20,000 cubic meter...

AI Technical Summary

Problems solved by technology

The preparation structure of the steel before quenching is ferrite + pearlite structure, and there are more pro-eutectoid ferrite, resulting in poor hardenability. The overall quenching method must be adopted. If induction quenching with higher efficiency is adopted, prone to cracking

[0005] Chinese patent CN 103205643A discloses a high-hardness wear-resistant steel pipe and its manufacturing method. Its patented components (weight %) are: C: 0.60~0.75%, Si: 0.10~0.40%, Mn: 0.60~1.30%, P: ≤0.020%, S≤0.010%, Cu: 0.10~0.50%, Ni: 0.10~0.50%, N: 0.0030~0.010%, the rest is Fe and unavoidable impurities, which are obtained by annealing after hot rolling. Uniform pearlite structure, but the cost of precious metals such as Cu and Ni is added to the steel, and the cost of the steel is greatly increased. At the same time, there is reticular pro-eutectoid ferrite in the hot-rolled structure, and it is difficult to make the size of the spherical carbide Uniform and dispersed distribution, thus affecting the formability and hardenability of steel

This patented method requires reducing and rolling the steel pipe, which requires high thermoforming performance of the equipment

Images