Ultra-low carbon martensitic stainless steel seamless tube and manufacturing method thereof

Abstract

The invention discloses an ultra-low carbon martensitic stainless steel seamless tube. The ultra-low carbon martensitic stainless steel seamless tube is prepared from ultra-low carbon martensitic stainless steel. The ultra-low carbon martensitic stainless steel is prepared from the following components in percentage by mass: less than or equal to 0.03% of C, 0.1-0.5% of Si, 0.2-0.5% of Mn, less than or equal to 0.015% of P, less than or equal to 0.002% of S, 12.2-13.2% of Cr, 5.2-5.7% of Ni, 1.9-2.1% of Mo, 0.1-1.6% of Cu and the balance of Fe and other impurities. The seamless tube can be suitable for oil and gas fields. The invention also provides a manufacturing method of the seamless tube. The manufacturing method comprises the following steps: smelting; tube blank thermal processing;steel tube thermal processing; and thermal treatment, wherein the heating temperature of tube blank thermal processing is 1200-1280 DEG C, the heating temperature of tube manufacturing by means of anextruding method is 1150-1250 DEG C, the heating temperature of tube manufacturing by means of a perforating cold rolling method is 1200-1280 DEG C, and the temperatures for thermal treatment are as follows: quenching at 900-1050 DEG C and tempering at 550-680 DEG C. The seamless tube provided by the invention has excellent strength and corrosion resistance in a CO2 and Cl<-> coexisting corrosionenvironment and in high-temperature and high pressure conditions.

Description

technical field [0001] The invention relates to the field of stainless steel, in particular to an ultra-low carbon martensitic stainless steel seamless pipe suitable for oil and gas fields and a manufacturing method thereof. Background technique [0002] With the development of the global economy, the demand for oil and gas resources in countries around the world continues to grow, prompting the development of oil and gas fields to become deeper and deeper, and many ultra-deep and ultra-high pressure wells have emerged. The difficulty of exploration and development of high-pressure, high-temperature and ultra-high-pressure, high-temperature wells has suddenly increased, causing more and more problems in drilling, mainly related to oil well design, tools, processes, equipment, well control, reservoir stimulation, safety and material selection, etc. A series of problems, the most critical of which is the choice of materials. [0003] High-pressure, high-temperature and ultra-...

AI Technical Summary

Problems solved by technology

But this invention C content is too high, in CO 2 and Cl － The corrosion resistance in the coexistence environment is not enough, and at the same time there are too many types of alloying elements, and the microstructure change law in the heat treatment process is too complicated, which brings difficulties to the quenching and tempering treatment

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