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.
A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power ca...A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power cable and outer liquefied natural gas (LNG) pipeline. The flowing LNG could maintain the operating temperature of the inner HTS power cable within the range of 85 K-90 K, thus the Bi-2223 superconductors in the HTS power cable produce little Joule loss with the transmission current below the critical current. Owing to the advantages of high power density, low transmission losses and economical manufacturing costs, the hybrid energy transmission pipeline is expected to be widely utilized in the near future. In order to ensure the safety of the HTS power cable and explosive LNG in case of short-circuit faults, this paper tests and analyzes the characteristics of Bi-2223 HTS tapes of the Type HT-CA, Type HT-SS and Type H models under short-circuit current impacts at the LNG cooling temperature (85 K-90 K). An experimental platform is designed and established for the ampacity tests of HTS tapes above LN2 cooling temperature (77 K). The AC over-current impact tests at 85 K-90 K are carried out on each sample of Bi-2223 tapes respectively, and the experimental results are analyzed and compared to evaluate their performances under different operating conditions. The results indicate that the Type HT-CA tape can withstand 50 Hz short-circuit current impact with the amplitude of 1108 A (10 times of critical current Ic ) for 100 ms at 90 K, and its resistance is the smallest of the three tested samples under similar current impacts. Therefore, the Type HT-CA Bi-2223 tape is the optimal superconductor of the HTS power cable in the hybrid energy transmission pipeline.展开更多
In this study,structural theory was used to examine the geometric configuration of channels embedded inside an object in the presence of internal heat generation for cooling by a heat transfer mechanism.The growth and...In this study,structural theory was used to examine the geometric configuration of channels embedded inside an object in the presence of internal heat generation for cooling by a heat transfer mechanism.The growth and development of gas transmission lines and the lack of up-to-date integrated information systems have made the design and maintenance of pipelines,as well as the handling of problems caused by various accidents in the pipeline,very complex in many cases.Using accurate descriptive and spatial information in tolls on gas transmission line maps such as pipes,booster stations,valves,and forks in a spatial reference database can engage planners,operators,and paramedics in a variety of management.They are used to help in the direction of optimal and purposeful management.Therefore,in this paper,by considering appropriate laboratory conditions and numerical experiments and calculations,it is possible to determine the optimal attraction of duct holes for cooling components of the gas transmission system,so that the industry can produce and developed gas transmission without incident.In this study,in addition to studying the geometric characteristics of channel spacing and their length,the dimensions of a specific channel for reducing the maximum produced temperature are also discussed.展开更多
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,exi...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
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
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.
基金supported by National Key R&D Project under Grant(2018YFB0904400).
文摘A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power cable and outer liquefied natural gas (LNG) pipeline. The flowing LNG could maintain the operating temperature of the inner HTS power cable within the range of 85 K-90 K, thus the Bi-2223 superconductors in the HTS power cable produce little Joule loss with the transmission current below the critical current. Owing to the advantages of high power density, low transmission losses and economical manufacturing costs, the hybrid energy transmission pipeline is expected to be widely utilized in the near future. In order to ensure the safety of the HTS power cable and explosive LNG in case of short-circuit faults, this paper tests and analyzes the characteristics of Bi-2223 HTS tapes of the Type HT-CA, Type HT-SS and Type H models under short-circuit current impacts at the LNG cooling temperature (85 K-90 K). An experimental platform is designed and established for the ampacity tests of HTS tapes above LN2 cooling temperature (77 K). The AC over-current impact tests at 85 K-90 K are carried out on each sample of Bi-2223 tapes respectively, and the experimental results are analyzed and compared to evaluate their performances under different operating conditions. The results indicate that the Type HT-CA tape can withstand 50 Hz short-circuit current impact with the amplitude of 1108 A (10 times of critical current Ic ) for 100 ms at 90 K, and its resistance is the smallest of the three tested samples under similar current impacts. Therefore, the Type HT-CA Bi-2223 tape is the optimal superconductor of the HTS power cable in the hybrid energy transmission pipeline.
基金The article was prepared as part of the state task“Research and development of complex energy-saving and thermoelectric regenerative systems”Application No.2019–1497,Subject No.FZWG-2020-0034.
文摘In this study,structural theory was used to examine the geometric configuration of channels embedded inside an object in the presence of internal heat generation for cooling by a heat transfer mechanism.The growth and development of gas transmission lines and the lack of up-to-date integrated information systems have made the design and maintenance of pipelines,as well as the handling of problems caused by various accidents in the pipeline,very complex in many cases.Using accurate descriptive and spatial information in tolls on gas transmission line maps such as pipes,booster stations,valves,and forks in a spatial reference database can engage planners,operators,and paramedics in a variety of management.They are used to help in the direction of optimal and purposeful management.Therefore,in this paper,by considering appropriate laboratory conditions and numerical experiments and calculations,it is possible to determine the optimal attraction of duct holes for cooling components of the gas transmission system,so that the industry can produce and developed gas transmission without incident.In this study,in addition to studying the geometric characteristics of channel spacing and their length,the dimensions of a specific channel for reducing the maximum produced temperature are also discussed.
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.
