Erosion wear is a common failure mode in the oil and gas industry.In the hydraulic fracturing,the fracturing pipes are not only in high-pressure working environment,but also suffer from the impact of the high-speed so...Erosion wear is a common failure mode in the oil and gas industry.In the hydraulic fracturing,the fracturing pipes are not only in high-pressure working environment,but also suffer from the impact of the high-speed solid particles in the fracturing fluid.Beneath such complex conditions,the vulnerable components of the pipe system are prone to perforation or even burst accidents,which has become one of the most serious risks at the fracturing site.Unfortunately,it is not yet fully understood the erosion mechanism of pipe steel for hydraulic fracturing.Therefore,this article provides a detailed analysis of the erosion behavior of fracturing pipes under complex working conditions based on experiments and numerical simulations.Firstly,we conducted erosion experiments on AISI 4135 steel for fracturing pipes to investigate the erosion characteristics of the material.The effects of impact angle,flow velocity and applied stress on erosion wear were comprehensively considered.Then a particle impact dynamic model of erosion wear was developed based on the experimental parameters,and the evolution process of particle erosion under different impact angles,impact velocities and applied stress was analyzed.By combining the erosion characteristics,the micro-structure of the eroded area,and the micro-mechanics of erosion damage,the erosion mechanism of pipe steel under fracturing conditions was studied in detail for the first time.Under high-pressure operating conditions,it was demonstrated through experiments and numerical simulations that the size of the micro-defects in the eroded area increased as the applied stress increased,resulting in more severe erosion wear of fracturing pipes.展开更多
Two new ar-bisabol sequiterpenes,(+)-(7S,10S)-10-epi-7,10-epoxy-3-hydroxy-ar-bisabol-11-ol(1)and(+)-(7R,8R,10S)-10-epi-7,10-epoxy-8-hydroxy-ar-bisabol-11-ol(2),have been isolated by a combination of various column chr...Two new ar-bisabol sequiterpenes,(+)-(7S,10S)-10-epi-7,10-epoxy-3-hydroxy-ar-bisabol-11-ol(1)and(+)-(7R,8R,10S)-10-epi-7,10-epoxy-8-hydroxy-ar-bisabol-11-ol(2),have been isolated by a combination of various column chromatographic techniques including reversed-phase semipreparative HPLC from an ethanol extract of the stem bark of Fraxinus sielboldiana.Their structures were determined by spectroscopic methods including IR,MS,and 1D and 2D NMR experiments.This is the first report of sequiterpenes in the genus Fraxinus.展开更多
基金supported by the National Natural Scienceof China (No.52175208)Scientific Research and Technology Development Project of CNPC (No.2023ZZ11)+1 种基金Fundamental Research and Strategic Reserve Technology Research Fund Project of CNPC (No.2023DQ03-03)Study on Key Technologies of Production Increase and Transformation of Gulong Shale Oil (2021ZZ10-04)。
文摘Erosion wear is a common failure mode in the oil and gas industry.In the hydraulic fracturing,the fracturing pipes are not only in high-pressure working environment,but also suffer from the impact of the high-speed solid particles in the fracturing fluid.Beneath such complex conditions,the vulnerable components of the pipe system are prone to perforation or even burst accidents,which has become one of the most serious risks at the fracturing site.Unfortunately,it is not yet fully understood the erosion mechanism of pipe steel for hydraulic fracturing.Therefore,this article provides a detailed analysis of the erosion behavior of fracturing pipes under complex working conditions based on experiments and numerical simulations.Firstly,we conducted erosion experiments on AISI 4135 steel for fracturing pipes to investigate the erosion characteristics of the material.The effects of impact angle,flow velocity and applied stress on erosion wear were comprehensively considered.Then a particle impact dynamic model of erosion wear was developed based on the experimental parameters,and the evolution process of particle erosion under different impact angles,impact velocities and applied stress was analyzed.By combining the erosion characteristics,the micro-structure of the eroded area,and the micro-mechanics of erosion damage,the erosion mechanism of pipe steel under fracturing conditions was studied in detail for the first time.Under high-pressure operating conditions,it was demonstrated through experiments and numerical simulations that the size of the micro-defects in the eroded area increased as the applied stress increased,resulting in more severe erosion wear of fracturing pipes.
基金Financial support from the National Natural Sciences Foundation of China(NNSFC,Grant nos.30825044 and 20932007)the National Science and Technology Project of China(Nos.2009ZX09311-004 and 2009ZX09301-003-4-1)is acknowledged.
文摘Two new ar-bisabol sequiterpenes,(+)-(7S,10S)-10-epi-7,10-epoxy-3-hydroxy-ar-bisabol-11-ol(1)and(+)-(7R,8R,10S)-10-epi-7,10-epoxy-8-hydroxy-ar-bisabol-11-ol(2),have been isolated by a combination of various column chromatographic techniques including reversed-phase semipreparative HPLC from an ethanol extract of the stem bark of Fraxinus sielboldiana.Their structures were determined by spectroscopic methods including IR,MS,and 1D and 2D NMR experiments.This is the first report of sequiterpenes in the genus Fraxinus.
