Oil well pipe capable of expanding at large deformation and manufacturing method thereof

Abstract

The invention discloses an oil well pipe capable of expanding at large deformation, and the oil well pipe comprises the following chemical components in percentage by weight: 0.3-0.45% of C, not more than 0.05% of Si, 16-25% of Mn, not more than 0.01% of P, not more than 0.005% of S, 0.02-0.05% of N, 0.2-0.5% of Re, not more than 0.05% of Al and the balance of Fe and inevitable impurities. The manufacturing method of the oil well pipe comprises: after hot-rolling, heating the steel pipe to 950-1150 DEG C in a first heat treatment furnace, performing heat preservation for 1-3 hours, then taking out of the furnace, cooling with water through internal spraying and external showing at a cooling rate of more than 30 DEG C / s to room temperature, and according to the initial yield strength requirement, feeding the steel pipe into a second heat treatment furnace to carry out aging treatment at the temperature of 200-300 DEG C for 2-4 hours to obtain the oil well pipe the room-temperature structure of which is single-phase austenitic or austenite and carbide or nitride. In the design process of the oil well pipe provided by the invention, the manufacturability of the steel pipe, the performance of expandable pipes, the mechanical properties and external pressure collapse resistance of expanded pipes and the manufacturing cost are considered, the maximum radial expansion deformation rate can reach 35%, and the expanded oil well pipe has yield strength reaching the 90 psi steel level and can be used as a pipe for drilling oil and natural gas.

Description

technical field [0001] The invention belongs to the technical field of alloy steel, and in particular relates to a steel pipe for expansion pipes and a manufacturing method thereof. The steel pipes for expansion pipes are suitable for radial expansion in oil wells and gas wells to achieve the required borehole diameter. Background technique [0002] Expandable pipe technology is a practical technology developed in recent years. It uses a mechanical expansion device and is propelled by liquid pressure. When the expansion cone or mandrel is advanced, the downhole pipe is plastically deformed to expand the pipe diameter. Expansion tubes are divided into two categories: solid expansion tubes and slotted expansion tubes. The solid expansion tube is mainly used to: seal the lost zone and high-pressure water layer; seal the rupture zone; repair the damaged casing and plug the perforated casing; replace the conventional liner hanger and liner hanger packer, so that Maintains boreho...

AI Technical Summary

Problems solved by technology

For example, the Japanese patent with the application number PCT / JP2006 / 312080 only pointed out that the oil well pipe invented by it has excellent impact performance after pipe expansion, and did not mention the properties such as uniform elongation and yield strength ratio which are crucial to the expansion and deformation performance of steel pipes ; and the Chinese patent application number 200410019863.X does not mention the impact performance of the oil well pipe after pipe expansion; while the U.S. patent No. 7225868 and the U.S. patent application No. 11790874 do not mention the expansion deformation of the steel pipe Uniform elongation, yield strength ratio, and no introduction to the impact performance of oil well pipe after pipe expansion

And the application number is that the Japanese patent of PCT / JP2008 / 054747, the Chinese patent that the application number is 200610112983.3, the U.S. patent that the patent number is 6851455 all use Cr, Ni, Mo stainless steel as the raw material of expansion tube, and the alloy cost of raw material and manufacturing cost are relatively high. High, the manufacturing process of raw materials is very difficult to implement in steel mills, and also loses the original intention of cost-saving expansion tube drilling technology

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