Results 71 to 80 of about 6,092 (204)
Dianci bileiqi, 2020 针对三维裂纹尖端应力强度因子计算困难的现状,提出了一种新型的三维裂纹应力强度因子计算方法,通过与其它方法在计算含圆孔平板裂纹尖端应力强度因子的对比分析,验证了本文应力强度因子计算方法的有效性和优越性。建立含裂纹缺陷的高压断路器瓷套有限元数值模型,将本文方法应用于高压断路器瓷套裂纹的应力强度因子计算,研究了高压断路器瓷套表面裂纹应力强度因子与瓷套所处环境温度、裂纹分布位置和裂纹尺寸的变化关系,获得了易导致瓷套断裂的环境、裂纹分布位置和裂纹尺寸,为电力行业中断路器瓷套的设计及运行维护提供有效的技术指导和借鉴。
赵滨滨, 王莹, 徐晓萌, 崔文婷
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Multi dimensional segmented hydraulic fracturing impact ground pressure control and loss reduction technology for deep buried thick coal seam hard roof [PDF]
Hydraulic fracturing technology is one of the effective methods for weakening the roof of coal mines and preventing rockburst. This article takes the 2305 thick coal seam fully mechanized caving working face of a coal mine in Shaanxi Province as the ...
Hui LI +7 more
core +1 more source
Shiyou jixie, 2014 针对目前国内外超低渗透油藏水平井压裂改造工艺复杂、工具应用效率低和可靠性差的现状，设计了不动管柱多级水力喷砂分段压裂工具，研发了投球式滑套喷射器与封隔器，将多套喷射器串接，施工时通过投球的方式逐级打开各级喷射器和封隔器，实现射孔及压裂。该工艺管柱具有井下工具少、不泄压投球等特点，能够不动管柱一次性完成水平井3层段分段压裂。现场试验结果表明，该工艺管柱性能可靠，提高了分段压裂改造成功率和施工效率，是一种先进、安全、可靠、高效的水平井分段改造工艺技术 ...
殷桂琴 +5 more
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Gaoya dianqi, 2020 GIS盆式绝缘子的静力特性问题是盆式绝缘子制造和运维中的关键问题。文中建立了252 kV正常或含有缺陷盆式绝缘子的三维模型,采用有限元法计算了盆式绝缘子在不同气室压力、不同裂纹大小和不同母线温度下应力分布特性。研究结果表明,当盆式绝缘子两侧气室压力均为0.4 MPa时,最大应力为1.3 MPa,最大应力点为外法兰和绝缘子本体交界面附近。若下表面气室压力为0.1 MPa时,最大应力为12.3 MPa;若上表面气室压力为0.1 MPa时,最大应力为10.9 MPa,但均未超过环氧树脂的屈服强度40 MPa ...
高晋文 +5 more
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Zhejiang Daxue xuebao. Lixue ban, 2001 本文利用CHEN等给出的在横观各向同性压电无限体内币形裂纹上下表面作用对称法向点力和点电荷情形下的解，结合压电材料功的互等定理，用初等函数的形式给出了在压电无限体中任意一点作用任意点力和点电荷情形下币形裂纹的张开位移，并对PZT-4压电陶瓷和对应的非压电材料作了计算分析.
HUANGHong-du(黄弘读) +1 more
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Fracturing fracture propagation law of coal seam and its influencing factors in the Shizhuang North Block [PDF]
It is of great significance to reveal the law of fracturing fracture propagation and influencing factors in coalbed methane (CBM) reservoirs for the formulation of fracturing technology and the efficient development of CBM resources.
Li WANG +3 more
core +1 more source
Shiyou jixie, 2012 针对水平井分段有效压裂难题，研发了水力分段射孔压裂配套工具。该工具主要由万向接头、偏心定位器、喷射器、单流阀等组成。应用水力分段射孔压裂工艺对吴平1井、吴平6井等6口井进行了作业。应用结果表明，美国喷嘴抗磨性能优于硬质合金喷嘴，压裂阶段排量保持在1.8 m3/min左右时，分阶段加大砂质量浓度对喷嘴损伤影响不大，目前喷射器设计壁厚28 mm，安全系数较高，可以满足喷射压裂3段的安全需要。
丁青山 +4 more
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Gaoya dianqi, 2022 高压断路器液压弹簧机构受制造技术、安装工艺、运行环境等因素影响，运行中可能会出现闭锁、误动、拒动、无法储能、频繁打压等问题。文中基于500 kV H变电站5061断路器液压弹簧机构打压频繁现象，机构解体后发现工作缸内壁高、低压油道孔壁处存在贯穿性裂纹，进而建模进行受力分析，结合裂纹处无损检测、金相组织、电镜分析等试验结果，推定工作缸高压、低压油道孔壁处因应力腐蚀造成开裂，导致设备运行时高压液压油内漏至低压液压油管路，从而引起机构频繁打压。据此，结合停电计划抽查同型号设备，建议厂家加强工艺管控 ...
刘亚林 +4 more
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Research and application on megawatt level intelligent fracturing pump system in coal mine [PDF]
This paper presents the development of a megawatt-scale intelligent fracturing pump system for underground coal mines, designed to address the escalating demands for flow and pressure in large-scale regional fracturing applications, particularly in hard ...
Bo LIU +13 more
core +1 more source
Three-dimensional pressure-relief prevention and control technology and its application in deep gob-side entry [PDF]
In response to the challenges posed by significant deformation and maintenance difficulties in the surrounding rock of deep gob-side entries. This study focuses on the 7312 head entry as the research background.
Changqing LI +6 more
core +1 more source