Recycling of AZ91 Mg alloy through consolidation of machined chips by extrusion and ECAP

AZ91 Mg alloy recycled by a solid state process and equal channel angular pressing(ECAP)exhibited a superior strength. The mechanical properties of AZ91 Mg alloy recycled from machined chips by extrusion at 623 K and ECAP at 573 K and 623 K were compared with those of the reference alloy which was produced from an as-received AZ91 Mg alloy block under the same conditions as the recycled alloy.The recycled specimens show a higher strength at room temperature than the reference alloy.The improvement of the tensile properties is attributed not only to the small grain size,but also to the dispersed oxide contaminants.

阜东5井区不下技术套管固井技术研究与应用

阜东5井区位于准噶尔盆地中央坳陷阜康凹陷东斜坡北74井北侏罗系头屯河组岩性圈闭。该井区简化井身结构采用二开结构,裸眼井段增加。根据测井和录井显示在2720-2891m井段为油气显示段,气测值由18000升至56000ppm,部分井地层有出水现象,对水泥浆抗水侵、防气侵的性能要求较高。由于二开采用复合井眼井径不规则,井壁虚泥饼和井筒岩屑不易携带干净,存在着下套管下不到底,固井施工时出现蹩泵的风险。通过分析研究,总结出一套适合长裸眼井段不下技术套管的配套工艺技术,全年完成8口探井固井作业,固井质量合格率100%,优质率82%。