Method for manufacturing seamless pipeline pipe from low-carbon martensite pulp conveying wear-resistant seamless pipeline steel

Abstract

The invention provides a method for manufacturing a seamless pipeline pipe from low-carbon martensite pulp conveying wear-resistant seamless pipeline steel. The method comprises the following steps: performing steelmaking, namely preparing the low-carbon martensite pulp conveying wear-resistant seamless pipeline steel according to a weight ratio; smelting by adopting an electric furnace or a converter together with an LF (ladle furnace) and a VD (vacuum degasser), wherein before tapping of the electric furnace or the converter, P is required to be less than or equal to 0.010%, then refining with the LF and VD is performed, S is ensured to be less than or equal to 0.005%, [N] is ensured to be less than or equal to 0.0080%, and [O] is ensured to be less than or equal to 0.0020% after refining, an appropriate amount of Al wires are fed at the last stage of the LF, then Fe-Ti wires and Si-Ca wires are fed, and B wires or Fe-B wires are fed before VD vacuum treatment; performing continuous casting; rolling; and processing and performing heat treatment to obtain a seamless pipeline pipe. The method provided by the invention has the effects that a low-carbon boron-containing micro-alloy steel type is adopted, the steel pipe is high in hardenability, a pipe body structure is a martensitic structure, the hardness is 360-440HBW, the wear resistance is good, the welding performance is good, and the low-temperature impact performance is good, so that the pipe is suitable for transportation and treatment of mining tailings. The seamless pipeline pipe can also be used for transmitting semi-fluid and can meet requirements of a concrete pumping system, sludge waste transportation and the like for seamless wear-resistant steel pipes.

Description

technical field [0001] The invention belongs to the manufacturing technology of seamless steel pipes in the metallurgical industry, and relates to a method for manufacturing seamless line pipes suitable for high-strength and high-toughness low-carbon martensitic slurry transporting wear-resistant seamless pipeline steels. Background technique [0002] Slurry pipeline transportation is a transportation method that mixes granular minerals, such as iron ore, coal ore and other solid materials, with liquid transportation media, and uses pump power to transport them in the pipeline. At present, there are mainly three types of pipeline materials for transporting ore slurry: one is the black Mesa coal pipeline project in the United States, and the API 5L standard X series steel grades used for the domestic Kunming Iron and Steel Dahongshan Iron Mine slurry pipeline, such as X52, X60, X65, etc., the characteristics of these steels are designed to meet the safety of oil and gas trans...

AI Technical Summary

Problems solved by technology

At present, there are mainly three types of pipeline materials for transporting ore slurry: one is the black Mesa coal pipeline project in the United States, and the API 5L standard X series steel grades used for the domestic Kunming Iron and Steel Dahongshan Iron Mine slurry pipeline, such as X52, X60, X65, etc., the characteristics of these steels are designed to meet the safety of oil and gas transportation. They all use extremely low carbon content. The metallographic structure is ferrite + pearlite, and the welding performance is excellent. The disadvantage is that the hardness is low, so it is wear-resistant. Poor performance, high pipe wall wear rate, resulting in greatly reduced pipe life

The second type is medium-high carbon rare earth alloy cast steel pipes that adopt centrifugal casting, such as ZG40CrNiMoMnSiRe wear-resistant cast steel pipes, etc., which have the advantages of high hardness and good wear resistance, but the disadvantages are high carbon content and alloy content, and poor welding performance.

The third type is the wear-resistant ceramic pipe lined with high wear resistance, but the manufacturing cost is high, welding is difficult, and it is difficult to manufacture large-diameter pipes

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