HTP practice,alloyed with low-carbon(less than 0.06%)and high-niobium(up to 0.11%),has been developed to produce large-wall X80 hot rolled strip for 2nd West-East Gas Pipeline project successfully.In this paper,existi...HTP practice,alloyed with low-carbon(less than 0.06%)and high-niobium(up to 0.11%),has been developed to produce large-wall X80 hot rolled strip for 2nd West-East Gas Pipeline project successfully.In this paper,existing status of niobium at different rolling stage,such as reheating,rough rolling and final product and strengthening effects have been presented and analyzed systematically.Some technological questions concerrned,such as the mixed grain occurred on the delay table,dynamic recrystallization during the finish rolling course,γ→αtransformation and final microstructure obtained at low coiling temperature,have been explored further.Analytical results presented increased recrystallization stop temperature due to high niobium contents can provide the requisite to remove waiting-temperature operation of transfer bar before finish rolling to ensure controlled effect of traditional low-temperature,which is benificial not only to production efficiency,but also to uniformity of austenite microstructure.Secondly,dynamic-recrystallization occurred during finish rolling may reduce the density of dislocation,but will better the grain gradient along the thickness because the dynamic recrystallization proceeds instantly,which is beneficial to reduce the appearance of separation of impact fracture.Finally,the lower coiling temperature than traditional TMCP practice,up to 300℃,is a key factor to obtain low-carbon bainite microstructure composed of acicular ferrite and small amount M/A component,which results in high strength and excellent low-temperature toughness.展开更多
On July 4 2002, a project attracting world attention, i.e., the West-East Gas Pipeline Project was declared in full-scale commencement. The project will write history with its enormous social and economic benefits.
The Bangladeshi government signed a framework agreement with China for construction of a 220-km pipeline to carry oil from tankers in the Bay of Bengal to storage plants on Chinese mainland. Bangladesh＇s Economic Rel...The Bangladeshi government signed a framework agreement with China for construction of a 220-km pipeline to carry oil from tankers in the Bay of Bengal to storage plants on Chinese mainland. Bangladesh＇s Economic Relations Department （ERD） Secretary Kazi Shofiqul Azam and Chinese Ambassador to Bangladesh Ma Mingqiang signed the framework agreement in the capital of Dhaka.展开更多
In the research, problems and damages of soil erosions in West -East Natural Gas Transmission were analyzed; the reasons were summarized and the characteristics of soil erosion were researched in order to explore prin...In the research, problems and damages of soil erosions in West -East Natural Gas Transmission were analyzed; the reasons were summarized and the characteristics of soil erosion were researched in order to explore principles of pipeline prevention and seek countermeasures.展开更多
With the increase in energy demand, the demand for oil and gas transmission pipes, particularly high-grade longitudinal submerged arc welded pipes （LSAWs）, have been growing in recent years. The construction of the ...With the increase in energy demand, the demand for oil and gas transmission pipes, particularly high-grade longitudinal submerged arc welded pipes （LSAWs）, have been growing in recent years. The construction of the 2nd West -East natural gas transmission pipeline project shows that the oil and gas pipeline construction has entered a new phase of development with X80 pipes being applied in large scales for the first time in China. This paper briefly introduces the 2nd West-East natural gas transmission pipeline project and its main technical requirements with the focus on the features of API standard 5L X80 grade Ф 1219 mm series of U-ing-O-ing-Expanding （ UOE ） LSAW pipes, which Baosteel developed with the integrated technology for the 2nd West-East natural gas transmission pipeline project. The analysis shows the extra-low carbon content, the high contents of manganese and niobium, the fine microstructure, the high strength,the toughness and the good weldability of X80 pipes meet the requirements of ＂the technical specification of LSAW linepipes for the 2nd West-East natural gas transmission pipeline project in China＂. By the end of June 2010, Baosteel had totally produced 322000 t of Ф 1219 mm X80 UOE steel pipes, which have been successfully used in the 2nd West-East natural gas transmission pipeline project, thus filling the gap of the production of large diameter X80 UOE LSAW pipes in China.展开更多
The development and supporting technologies of high-strain line pipe steel and pipes used for oil and gas pipeline projects in special geological environments(such as earthquake zone,landslide zone,mine goaf and subsi...The development and supporting technologies of high-strain line pipe steel and pipes used for oil and gas pipeline projects in special geological environments(such as earthquake zone,landslide zone,mine goaf and subsidence zone)is one of the international research hotspots,and it is also a major problem that China's major oil and gas pipeline projects have to solve.Focusing on a series of key technical difficulties in the research&development and application of high-strain line pipe steel and pipes,a number of theoretical and technological innovations have been achieved after more than ten years of joint researches.And the main achievements are as follows.First,the method of applying many different parameters(e.g.stress ratio,yield to tensile ratio and uniform elongation(UEL))to comprehensively characterize and evaluate the deformation behavior of steel pipes is proposed,and a technical index system and standard for the new products of X70HD/X80HD high-strain line pipe steel and pipes are established.Second,a complete set of X70HD/X80HD steel plate manufacturing technology is researched and developed,and the high-strain steel plate with the properties of low yield to tensile ratio,high uniform elongation,high stress ratio and high strength and toughness is worked out.Third,the X70HD/X80HD JCOE and UOE high-strain longitudinal submerged arc welded pipe manufacturing technology is researched and developed,reasonable performance matching between a steel pipe and a welding seam is realized,and the performance deterioration in the process of forming,welding,diameter-expending and thermal coating is solved.Fourth,a full-scale test device of steel pipe internal pressure t bending large deformation is independently developed,and the physical simulation based steel pipe deformation test technology is formed.X70HD/X80HD high-strain line pipe steel and pipes have been applied in the West to East Gas Pipeline,the ChinaeMyanmar Pipeline and other major gas pipeline projects in the large scale,and their application effects are remarkable.To satisfy the new needs of pipeline construction and long-term safe operation under complex geological conditions,some suggestions were put forwarded,such as developing new methods of strain-based pipeline design,and researching and developing or improving the supporting technologies suitable for the higher matching requirements of girth weld,such as welding methods,welding materials,welding processes,and girth weld performance quality and defect control requirements.展开更多
High-grade(API 5L X80)and large-diameter(OD 1422 mm)line pipes are used in the Sino-Russian eastern route gas pipeline project for high pressure(12 MPa)transmission,and this can significantly increase the transmission...High-grade(API 5L X80)and large-diameter(OD 1422 mm)line pipes are used in the Sino-Russian eastern route gas pipeline project for high pressure(12 MPa)transmission,and this can significantly increase the transmission capacity and meet China's energy strategic demand.With the increase of steel grade,transmission pressure,pipe diameter and design coefficient,however,ductile crack of line pipes becomes the dominant crack mode,so it is necessary to focus on crack arrest and control study.In this paper,therefore,an intensive study was performed on the Battelle Two-Curve(BTC)method which is the major solution to the calculation of arrest toughness,as well as the crack resistance curve and decompression curve.Based on the study,the principle and application range of the BTC method were confirmed.In addition,a series of analysis were conducted on the issues which occurred when the BTC method was applied to high-strength,high-toughness line pipe steel,and the commonly used modified approaches to BTC calculation results were also provided.After the crack control scheme of the X80 large OD 1422 mm line pipes for the Russian Bovanenkovo-Ukhta was reviewed,the BTC calculation results were corrected on the basis of the design parameters of the Sino-Russian eastern routine gas pipeline project,the Charpy V-notched(CVN)impact energy which meets the project requirement was finally worked out to be 245 J.展开更多
文摘HTP practice,alloyed with low-carbon(less than 0.06%)and high-niobium(up to 0.11%),has been developed to produce large-wall X80 hot rolled strip for 2nd West-East Gas Pipeline project successfully.In this paper,existing status of niobium at different rolling stage,such as reheating,rough rolling and final product and strengthening effects have been presented and analyzed systematically.Some technological questions concerrned,such as the mixed grain occurred on the delay table,dynamic recrystallization during the finish rolling course,γ→αtransformation and final microstructure obtained at low coiling temperature,have been explored further.Analytical results presented increased recrystallization stop temperature due to high niobium contents can provide the requisite to remove waiting-temperature operation of transfer bar before finish rolling to ensure controlled effect of traditional low-temperature,which is benificial not only to production efficiency,but also to uniformity of austenite microstructure.Secondly,dynamic-recrystallization occurred during finish rolling may reduce the density of dislocation,but will better the grain gradient along the thickness because the dynamic recrystallization proceeds instantly,which is beneficial to reduce the appearance of separation of impact fracture.Finally,the lower coiling temperature than traditional TMCP practice,up to 300℃,is a key factor to obtain low-carbon bainite microstructure composed of acicular ferrite and small amount M/A component,which results in high strength and excellent low-temperature toughness.
文摘On July 4 2002, a project attracting world attention, i.e., the West-East Gas Pipeline Project was declared in full-scale commencement. The project will write history with its enormous social and economic benefits.
文摘The Bangladeshi government signed a framework agreement with China for construction of a 220-km pipeline to carry oil from tankers in the Bay of Bengal to storage plants on Chinese mainland. Bangladesh＇s Economic Relations Department （ERD） Secretary Kazi Shofiqul Azam and Chinese Ambassador to Bangladesh Ma Mingqiang signed the framework agreement in the capital of Dhaka.
基金Supported by Scientific Research Program of Water Resources Department of the Xinjiang Uygur Autonomous Region (xjsl-2011-11)Young Core Project of Northwest A&F University (KZCXI-10-4-1)~~
文摘In the research, problems and damages of soil erosions in West -East Natural Gas Transmission were analyzed; the reasons were summarized and the characteristics of soil erosion were researched in order to explore principles of pipeline prevention and seek countermeasures.
文摘With the increase in energy demand, the demand for oil and gas transmission pipes, particularly high-grade longitudinal submerged arc welded pipes （LSAWs）, have been growing in recent years. The construction of the 2nd West -East natural gas transmission pipeline project shows that the oil and gas pipeline construction has entered a new phase of development with X80 pipes being applied in large scales for the first time in China. This paper briefly introduces the 2nd West-East natural gas transmission pipeline project and its main technical requirements with the focus on the features of API standard 5L X80 grade Ф 1219 mm series of U-ing-O-ing-Expanding （ UOE ） LSAW pipes, which Baosteel developed with the integrated technology for the 2nd West-East natural gas transmission pipeline project. The analysis shows the extra-low carbon content, the high contents of manganese and niobium, the fine microstructure, the high strength,the toughness and the good weldability of X80 pipes meet the requirements of ＂the technical specification of LSAW linepipes for the 2nd West-East natural gas transmission pipeline project in China＂. By the end of June 2010, Baosteel had totally produced 322000 t of Ф 1219 mm X80 UOE steel pipes, which have been successfully used in the 2nd West-East natural gas transmission pipeline project, thus filling the gap of the production of large diameter X80 UOE LSAW pipes in China.
基金Project supported by the National Key R&D Program of China“Research and Development of High-strain Marine Line Pipes”(No.2018YFC03010300)PetroChina's Major Science&Technology Project“Research on Key Technologies for Controlling Pipe Fracture and Deformation in the Second West-East Gas Pipeline”(No.2009E-0105)+1 种基金“Research and Development of Special Welded Pipes for the Second West-East Gas Pipeline”(No.2009E-0104)CNPC's Science&Technology Infrastructure Program“CNPC Infrastructure Construction of Key Laboratory for Petroleum Tubular Engineering”(No.07H611).
文摘The development and supporting technologies of high-strain line pipe steel and pipes used for oil and gas pipeline projects in special geological environments(such as earthquake zone,landslide zone,mine goaf and subsidence zone)is one of the international research hotspots,and it is also a major problem that China's major oil and gas pipeline projects have to solve.Focusing on a series of key technical difficulties in the research&development and application of high-strain line pipe steel and pipes,a number of theoretical and technological innovations have been achieved after more than ten years of joint researches.And the main achievements are as follows.First,the method of applying many different parameters(e.g.stress ratio,yield to tensile ratio and uniform elongation(UEL))to comprehensively characterize and evaluate the deformation behavior of steel pipes is proposed,and a technical index system and standard for the new products of X70HD/X80HD high-strain line pipe steel and pipes are established.Second,a complete set of X70HD/X80HD steel plate manufacturing technology is researched and developed,and the high-strain steel plate with the properties of low yield to tensile ratio,high uniform elongation,high stress ratio and high strength and toughness is worked out.Third,the X70HD/X80HD JCOE and UOE high-strain longitudinal submerged arc welded pipe manufacturing technology is researched and developed,reasonable performance matching between a steel pipe and a welding seam is realized,and the performance deterioration in the process of forming,welding,diameter-expending and thermal coating is solved.Fourth,a full-scale test device of steel pipe internal pressure t bending large deformation is independently developed,and the physical simulation based steel pipe deformation test technology is formed.X70HD/X80HD high-strain line pipe steel and pipes have been applied in the West to East Gas Pipeline,the ChinaeMyanmar Pipeline and other major gas pipeline projects in the large scale,and their application effects are remarkable.To satisfy the new needs of pipeline construction and long-term safe operation under complex geological conditions,some suggestions were put forwarded,such as developing new methods of strain-based pipeline design,and researching and developing or improving the supporting technologies suitable for the higher matching requirements of girth weld,such as welding methods,welding materials,welding processes,and girth weld performance quality and defect control requirements.
文摘High-grade(API 5L X80)and large-diameter(OD 1422 mm)line pipes are used in the Sino-Russian eastern route gas pipeline project for high pressure(12 MPa)transmission,and this can significantly increase the transmission capacity and meet China's energy strategic demand.With the increase of steel grade,transmission pressure,pipe diameter and design coefficient,however,ductile crack of line pipes becomes the dominant crack mode,so it is necessary to focus on crack arrest and control study.In this paper,therefore,an intensive study was performed on the Battelle Two-Curve(BTC)method which is the major solution to the calculation of arrest toughness,as well as the crack resistance curve and decompression curve.Based on the study,the principle and application range of the BTC method were confirmed.In addition,a series of analysis were conducted on the issues which occurred when the BTC method was applied to high-strength,high-toughness line pipe steel,and the commonly used modified approaches to BTC calculation results were also provided.After the crack control scheme of the X80 large OD 1422 mm line pipes for the Russian Bovanenkovo-Ukhta was reviewed,the BTC calculation results were corrected on the basis of the design parameters of the Sino-Russian eastern routine gas pipeline project,the Charpy V-notched(CVN)impact energy which meets the project requirement was finally worked out to be 245 J.
