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Application of Automatic TIG Welding for Yamal LNG Process Piping Fabrication
Zhijian Wang,
Yanyan Li,
Chiaming Chang
Issue:
Volume 6, Issue 4, July 2018
Pages:
44-49
Received:
5 June 2018
Accepted:
26 June 2018
Published:
24 July 2018
Abstract: The representative materials, used in Russian Yamal LNG project, are ASTM A333 Gr.6 (low temperature carbon steel, designed temperature of –50°C) and ASTM A312/A358 TP304/304L (austenitic stainless steel, designed temperature of –196°C). The welding technical specification demands TIG (Tungsten Inert Gas) welding for root welding of piping. This project adopts the construction way of prefabrication in Qingdao and assembly in Russian. Therefore, high construction accuracy is required. This article introduces the LNG process piping welding by automatic TIG welding which contains welding process design, welding process parameters, test and analysis of weld mechanical property and advantage analysis of TIG welding as well. In this project, the automatic and high efficient TIG welding is used for the root welding and hot welding of low temperature carbon steel and austenitic stainless steel piping. The result shows that the mechanical properties of weld metals meet the requirements of LNG project technical specification and code ASME B31.3. The efficiency of automatic TIG welding increases 2 times compared with conventional manual TIG welding. The automatic TIG welding improves and optimizes the quality and construction progress of the LNG project process piping.
Abstract: The representative materials, used in Russian Yamal LNG project, are ASTM A333 Gr.6 (low temperature carbon steel, designed temperature of –50°C) and ASTM A312/A358 TP304/304L (austenitic stainless steel, designed temperature of –196°C). The welding technical specification demands TIG (Tungsten Inert Gas) welding for root welding of piping. This pr...
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Simulation and Experimentation of Torkbuster Based on ANSYS/LS-DYNA
Hongyan Ma,
Jingwang Chen,
Daning Wang,
Shibo Su,
Xianjing Yang,
Xiangzhen Cheng,
Xiangjun Qu
Issue:
Volume 6, Issue 4, July 2018
Pages:
50-59
Received:
13 June 2018
Accepted:
5 July 2018
Published:
30 July 2018
Abstract: The stick-slip vibration in deep hard formation is a technical bottleneck restricting the efficient use of PDC bit. In order to combat the stick-slip phenomenon during drilling in deep hard formations, we introduced the high frequency self-excited torkbuster. Based on the analysis of the working principle of the torkbuster, a nonlinear dynamic three-dimensionalmodel of PDC bit is established by using the finite element software (ANSYS/LS-DYNA). The wear conditions and themotioncharacteristicsof the PDC bit as well as the failure of the rock are simulated with and without the action of the high frequency torsional impact, and several field experiments are conducted. The results show that the high frequency torsional impact force generated by the torkbuster can effectively improve the uniformity of the force on the PDC bit and rock, and restrain the stick-slip vibration and the damage of the cutters. The experimental results show that the torkbuster can improve the rock breaking efficiency and shorten the drilling cycle, and provide an important technical reference for the torsional impact technology applying in deep hard formations.
Abstract: The stick-slip vibration in deep hard formation is a technical bottleneck restricting the efficient use of PDC bit. In order to combat the stick-slip phenomenon during drilling in deep hard formations, we introduced the high frequency self-excited torkbuster. Based on the analysis of the working principle of the torkbuster, a nonlinear dynamic thre...
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Study on Coal Methane Adsorption Behavior Under Variation Temperature and Pressure-Taking Xia-Yu-Kou Coal for Example
Hao Jingyuan,
Li Dong,
Zhang Xuemei,
Ma Qinghua
Issue:
Volume 6, Issue 4, July 2018
Pages:
60-66
Received:
25 June 2018
Accepted:
9 July 2018
Published:
1 August 2018
Abstract: Based on the Langmuir volume and Langmuir pressure of Xiao-Yu-Kou #3 coal’s methane adsorption, Li’s adsorption-flow equation’s parameters have been calculated. LI adsorption-flow equation obtained can visually show and quantitatively calculate that how and how much variation temperature and pressure change the absorption capacity. Partial differential equation characterizes temperature has negative effects and pressure has positive effects. Therefore, under variation temperature and pressure conditions, coal adsorption capacity would have the maximum value.
Abstract: Based on the Langmuir volume and Langmuir pressure of Xiao-Yu-Kou #3 coal’s methane adsorption, Li’s adsorption-flow equation’s parameters have been calculated. LI adsorption-flow equation obtained can visually show and quantitatively calculate that how and how much variation temperature and pressure change the absorption capacity. Partial differen...
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Evaluation on the Organic Rankine Cycle Generator Sets Firstly Applied in China’s Petrochemical Industry
Chi Shenggang,
Zhou Tiantian,
Wang Fangsong
Issue:
Volume 6, Issue 4, July 2018
Pages:
67-73
Received:
2 July 2018
Accepted:
16 July 2018
Published:
14 August 2018
Abstract: The Organic Rankine Cycle (ORC) generator sets operated on the low-temperature waste heat device of an aromatics complex is the first demonstration set in the chinese petrochemical industry. By taking this set as an example, the paper introduced the circulation processes of the heating medium water and the ORC working medium in the low-temperature waste heat device. The author also summarized the process and equipment issues during the operation of the sets: in terms of process, improper design of bypass valves in the flow paths of hot water, control authority of the set is not available in DCS, and unstable generator loads under the influence of ambient temperature, etc.; in the field of equipment, bad equipment maintenance & repair as well as operability, manufacturing fault of KE710 generator, screw expander vibration, and loud running noise, etc. Exploring and solving the problems found in one cycle of the set operation are beneficial to the operation optimization of the ORC generator sets in the future. Therefore, the author proposed such solutions as redesigning the working medium circulating pump and using the latest and optimized screw expander, which resolved part of the problems as well as improved the reliability, maintainability and operability of the ORC generator sets. Through comparison between the calibration data and the operational data of the generator set under the same heat resources, it was found that the set’s operating load became less than its calibration load as the heat exchanger started to scale and the screw expander started to wear.
Abstract: The Organic Rankine Cycle (ORC) generator sets operated on the low-temperature waste heat device of an aromatics complex is the first demonstration set in the chinese petrochemical industry. By taking this set as an example, the paper introduced the circulation processes of the heating medium water and the ORC working medium in the low-temperature ...
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Investigation and Comparison of Emulsified Diesel Oil and Flomin C 9202 as a Collector in the Beneficiation of Ultra-Fine Coal by Agglo-Flotation
Richard Muthui Kasomo,
Sammy Ombiro,
Bernard Rop,
Nicholas Muthama Mutua
Issue:
Volume 6, Issue 4, July 2018
Pages:
74-80
Received:
10 July 2018
Accepted:
23 July 2018
Published:
18 August 2018
Abstract: Modern mechanized mining techniques produce enormous quantities of coal fines. Reagents regime (i.e. reagents usage and reagent type) is an important fundamental factor in the process of recovering and dashing of ultra-fine coals (coal fines). The other factors that are crucial for recovery and the purity of the final product obtained is the nature of the particle size of the solids as well as the adsorption of the reagent on the solid particles surface among others. Coal concentrators and mills have embark on the strategy of establishment fine coal benefaction reagents which are not only cheap but effective and efficient. In this study, the effects of both the Flomin C 9202 and Emulsified light diesel oil are investigated in regards to their performance on the combustible recovery as well as the ash remaining in the clean coal product. The study, further involves grinding the coal sample to obtain the fines sizes, flocculate the fines to get the agglomerates and finally float them, what is commonly referred to as Agglo-flotation. The results for both Flomin C 9202 and emulsified light diesel oil were analyzed and after obtaining the best collector (which in this case was Flomin C 9202) then the flowsheet was there after determined. The batch tests for collector determination showed that the Flomin C 9202 outperformed the emulsified diesel oil, and after conducting two stages flowsheet with the collector (Flomin C9202), the ash content was reduced from 22.78%(original coal sample) to 7.91% while the combustible recovery increased from 77.44% (original coal sample) to 92.85%.
Abstract: Modern mechanized mining techniques produce enormous quantities of coal fines. Reagents regime (i.e. reagents usage and reagent type) is an important fundamental factor in the process of recovering and dashing of ultra-fine coals (coal fines). The other factors that are crucial for recovery and the purity of the final product obtained is the nature...
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