Method for manufacturing transformation induced plasticity steel seamless tube on line

A phase change-induced plasticity and seamless pipe technology, applied in the field of steel rolling, can solve the problems of long heating time of steel pipe, unsatisfactory performance improvement effect, and difficulty in obtaining fine grains, etc., and achieve excellent cold forming performance, good strength-plasticity Matching, Effect of High Work Hardening Index

Inactive Publication Date: 2012-02-29
NORTHEASTERN UNIV
View PDF2 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The heating time of the steel pipe is long, and the influence on the microstructure of the steel pipe is that it is difficult to obtain fine grains, so that the process of refining the grains of the steel pipe encounters a bottleneck, and the performance improvement effect is not ideal

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for manufacturing transformation induced plasticity steel seamless tube on line
  • Method for manufacturing transformation induced plasticity steel seamless tube on line
  • Method for manufacturing transformation induced plasticity steel seamless tube on line

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] The chemical composition of the steel used in this embodiment is: 0.146%C, 1.227%Si, 1.321%Mn, 0.0295%Nb, 0.024%Ti, 0.004%S, 0.001%P, and the balance is Fe and impurities. ;

[0029] A cold-drawn seamless steel pipe with a wall thickness of 1.3mm and a diameter of 42mm is heated to a critical zone of 800°C at a heating rate of 35°C / s with an intermediate frequency heating induction coil, and annealed for 10s;

[0030] Compressed air is used for cooling, and the steel pipe annealed in the critical zone is cooled to 420°C in the bainite zone at a rate of 60°C / s, and isothermally treated for 30s;

[0031] The steel pipe after the isothermal treatment in the bainite zone is air-cooled to room temperature to obtain a phase transformation induced plasticity steel seamless pipe.

[0032] Metallographic samples were cut from the middle part of the prepared phase change induced plasticity steel seamless pipe, and after grinding and polishing, Lepera (mass fraction was 1%Na 2 S...

Embodiment 2

[0037] The chemical composition of the steel used in this embodiment is: 0.146%C, 1.127%Si, 1.321%Mn, 0.0295%Nb, 0.024%Ti, 0.003%S, 0.004%P, and the balance is Fe and impurities. ;

[0038] A cold-drawn seamless steel pipe with a wall thickness of 1.3mm and a diameter of 42mm is heated to a critical zone of 810°C at a heating rate of 600°C / s by an intermediate frequency heating induction coil, and annealed for 20s;

[0039]Compressed air is used for cooling, and the steel pipe annealed in the critical zone is cooled to 420°C in the bainite zone at a rate of 60°C / s, and isothermally treated for 30s;

[0040] Air-cool the steel pipe after isothermal treatment in the bainite zone to room temperature to obtain the phase transformation induced plasticity steel seamless pipe of the present invention.

[0041] The rapid heating in this example makes the steel pipe sample almost lose the preheating process, and the sample reaches the predetermined critical temperature in a very short...

Embodiment 3

[0045] The chemical composition of the steel used in this embodiment is: 0.14%C, 1.30%Si, 1.60%Mn, 0.015%Nb, 0.02%Ti, 0.002%S, 0.002%P, and the balance is Fe and impurities.

[0046] A cold-drawn seamless steel pipe with a wall thickness of 5mm and a diameter of 1000mm is heated to a critical zone of 850°C at a heating rate of 400°C / s with an intermediate frequency heating induction coil, and annealed for 5s;

[0047] Cool the steel pipe after the annealing treatment in the critical zone to 450℃ in the bainite zone at a rate of 80℃ / s by using compressed air for cooling, and perform isothermal treatment for 40s;

[0048] The steel pipe after the isothermal treatment in the bainite zone is water-cooled to room temperature to obtain the phase transformation induced plasticity steel seamless pipe of the present invention.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
tensile strengthaaaaaaaaaa
tensile strengthaaaaaaaaaa
elongationaaaaaaaaaa
Login to view more

Abstract

The invention belongs to the technical field of steel rolling, and particularly relates to a method for manufacturing a transformation induced plasticity steel seamless tube on line. The method comprises the following steps of: heating a wall cold-drawing seamless steel tube to a critical region of between 760 and 850 DEG C by using an intermediate frequency heating induction coil at a heating speed of at least 35 DEG C / s; cooling to a bainite region of between 380 and 450 DEG C at a speed of between 40 and 80 DEG C / s, and performing isothermal treatment for 10 to 40 seconds; and performing air cooling, water cooling or cooling naturally to a room temperature to obtain the transformation induced plasticity steel seamless tube. By measuring the transformation induced plasticity steel seamless tube prepared by the technical scheme, the tensile strength is 780 MPa level, the percentage of elongtation is more than or equal to 24 percent, a ratio of tensile strength to yield strength is less than or equal to 0.55, and a strain hardening index n is more than or equal to 0.24.

Description

technical field [0001] The invention belongs to the technical field of steel rolling, and in particular relates to a method for on-line manufacturing phase transformation-induced plasticity steel seamless pipes. Background technique [0002] In the field of modern steel preparation, in order to achieve the purpose of saving materials and reducing energy loss during transportation, in addition to using higher-strength materials, another effective way is to use "substituting empty for solid" energy-saving lightweight components, and the The two are organically combined to achieve the effects of material saving and energy saving in steel preparation. With the continuous improvement of steel pipe secondary forming technology such as internal high pressure forming, the industrial production of high-strength hollow components has become possible, and the research on steel pipe manufacturing technology with high strength and high formability has also attracted much attention. [0...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C21D8/10C22C38/14
Inventor 张明亚朱伏先马世成李艳梅刘纪源
Owner NORTHEASTERN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap