Thick-wall super 13Cr seamless steel pipe with yield strength of 125 steel grade and production method

Abstract

The invention relates to a thick-wall super 13Cr seamless steel pipe with a yield strength of 125 steel grade and a production method. The performance of the seamless steel pipe is characterized in that a tensile strength is larger than or equal to 896 MPa, an Rp0.2 yield strength is 862 MPa to 1034 MPa, and an elongation is larger than or equal to 12%. The production method of the seamless steel pipe comprises the following steps of (1) producing a super 13Cr casting blank through electric furnace smelting and continuous casting; (2) annealing the casting blank to reduce hardness; (3) processing the blank to remove surface oxide skin, central porosity and cracks; (4) conducting electromagnetic induction heating to 1150 DEG C to 1220 DEG C, and conducting hot extrusion forming; (5) conducting preheating treatment, specifically, heating the steel pipe to 960 DEG C to 1010 DEG C and cooling the steel pipe to a room temperature through air blowing; and (6) heating to 960 DEG C to 1010 DEG C, quickly cooling quenching oil, heating to 560 DEG C to 610 DEG C, and tempering to obtain the super 13Cr steel pipe with the 125 steel grade performance. According to the steel pipe and the method, a yield and quality of the seamless steel pipe are improved, the production cost is reduced, and the seamless steel pipe is good in surface quality, high in oil quenching heat treatment mechanical performance, high in strength and good in toughness.

Description

technical field [0001] The invention belongs to the field of industrial equipment production, and in particular relates to a thick-walled super 13Cr seamless steel pipe with a yield strength of 125 steel grades and a production method. Background technique [0002] With the gradual depletion of shallow wells and relatively easy-to-develop oil fields in the world, and the increasing demand for energy in various countries, people have to turn to oil fields containing carbon dioxide corrosion in deep wells with harsher geological conditions. L80-13Cr is a kind of steel used in oil development, which has good carbon dioxide corrosion resistance and is a low-cost corrosion-resistant alloy. In oil field production, L80-13Cr seamless steel pipe is widely used. [0003] As the depth of oil wells increases, the geological conditions become more complicated. The ordinary low-grade steel L80-13Cr is difficult to withstand the pressure generated by complex geology, and materials with hi...

AI Technical Summary

Problems solved by technology

In the case of the same material composition, L80-13Cr can be quenched and tempered to 125ksi steel grade by reducing the tempering temperature or tempering time, but at this time, the plasticity and toughness of this composition are greatly reduced, the brittleness is extremely high, and it is easy to crack ,can not be used

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