Steel sheet for thick-walled high-strength line pipe having exceptional souring resistance, crush resistance properties, and low-temperature ductility, and line pipe

A technology of low temperature toughness and acid resistance, applied in the field of thick-walled and high-strength line pipe steel plate, which can solve the problems of crush resistance and low temperature toughness difficulty.

Active Publication Date: 2015-12-09
NIPPON STEEL CORP
View PDF9 Cites 21 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the thickening of the wire pipe, it is very diffic

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
  • Steel sheet for thick-walled high-strength line pipe having exceptional souring resistance, crush resistance properties, and low-temperature ductility, and line pipe
  • Steel sheet for thick-walled high-strength line pipe having exceptional souring resistance, crush resistance properties, and low-temperature ductility, and line pipe
  • Steel sheet for thick-walled high-strength line pipe having exceptional souring resistance, crush resistance properties, and low-temperature ductility, and line pipe

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0182] Next, examples of the present invention will be described, but the present invention is not limited to the conditions employed in the following examples.

[0183] Steels having the chemical components shown in Table 1-1, Table 1-2, Table 2-1, and Table 2-2 were melted and cast to produce billets. "Slab thickness" in Table 3-1 and Table 3-2 represents the thickness (mm) of the obtained slab. The steel slabs mentioned above are reheated respectively, and hot rolled in a recrystallized region exceeding 900°C. In addition, the "heating temperature" in Table 3-1 and Table 3-2 represents the above-mentioned reheating temperature, and the "transfer thickness" in Table 3-1 and Table 3-2 represents the temperature after hot rolling in the above-mentioned recrystallization region and which will be described later. Sheet thickness at 900°C before hot rolling in the non-recrystallized region of 900°C or lower. In addition, the "reduction ratio in the recrystallization domain" of ...

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
Yield stressaaaaaaaaaa
Tensile strengthaaaaaaaaaa
Tensile strengthaaaaaaaaaa
Login to view more

Abstract

Provided are a steel sheet for thick-walled high-strength line pipe having exceptional souring resistance, crush resistance properties, and low-temperature ductility, and a production method for the same. The steel sheet for thick-walled high-strength line pipe has sheet thickness of 25 mm to 45 mm, inclusive, the metal texture of the surface layer including worked ferrite at a level of 5% or more and Sfe1% or less as calculated using the following equation 1a, and a martensite-austenite hybrid (MA) at a level of 8% or less, with the remainder comprising polygonal ferrite and/or bainite, and the metal texture of a center section of the sheet thickness including worked ferrite at a level of 5% or less, and MA at a level of 5% or less, with the remainder comprising either acicular ferrite and/or bainite, or both. The average value of effective crystal grain diameter in the surface layer and the center section is 20 μm. Sfe1 = 0.6552 × TH - 4.7826 … Equation 1a. TH is the sheet thickness of the steel sheet.

Description

technical field [0001] The present invention relates to a thick-walled high-strength linepipe steel plate excellent in acid resistance, crush resistance, and low-temperature toughness, and in particular to the acid resistance, crush resistance, and low-temperature toughness of raw materials for line pipes for natural gas or crude oil transportation Excellent thick-walled high-strength wire and pipe steel and wire pipe. Background technique [0002] In recent years, pipelines have become more and more important as a long-distance transportation method for crude oil and natural gas. The idea of ​​designing line pipes for long-distance transportation is mainly based on the standards of the American Petroleum Institute (API). Conventionally, line pipes with excellent tensile strength and low-temperature toughness have been developed in order to prevent cracking when loaded with internal pressure. [0003] When the internal pressure is increased to improve the transportation eff...

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
IPC IPC(8): C22C38/00C21D8/02C22C38/14C22C38/58
CPCC21D8/02C21D8/0226C21D8/0263C21D8/105C21D9/08C21D9/14C21D2211/002C21D2211/005C22C38/00C22C38/14C22C38/58C21D1/78C21D2221/10C22C38/12
Inventor 原卓也藤城泰志篠原康浩津留英司
Owner NIPPON STEEL CORP
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