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51.
新型热压WC-Fe基金刚石钻头钻进试验   总被引:1,自引:0,他引:1  
为满足硬岩钻探的需要,将传统的热压碳化钨(WC)基金刚石钻头胎体中一部分WC用Fe代替,用Excel中的回归分析和非线性规划求解计算出的最优胎体配方,试制了新型热压WC-Fe基金刚石钻头,在可钻性为8级以上的岩石上进行了室内、外钻进试验,取得了较好的效果。   相似文献   
52.
Long-term water quality monitoring data from two riverine lakes in the Upper Mississippi River basin, Lakes St. Croix and Pepin, were analyzed to compare the long-term average water quality conditions and land use distributions, water quality trends and loads at lake inlets and outlets, trends from long-term versus short-term monitoring records, and the ability of paleolimnological cores to accurately infer lake water quality conditions. During the 1976–2004 period, the long-term average concentrations of nutrients, suspended solids, and chlorophyll-a were consistently lower at the Lake St. Croix inlet versus the Lake Pepin inlet, which drains a greater proportion of urban and agricultural runoff. Despite these differences, nutrient trends were similar at the inlets to both lakes; reductions in total phosphorus and ammonium concentrations were attributed to improvements in point source technologies, whereas increasing nitrate concentrations were attributed to both point source changes and nonpoint source increases. Despite improvements in several water quality variables, nitrate concentrations are increasing in both lakes, sediment trends indicate persistent nonpoint source inputs to Lake Pepin, and current total phosphorus concentrations remain well above pre-1950s levels in both lakes. Since urban development and agriculture are increasing in the Lake St. Croix and Lake Pepin Watersheds, continued point source regulation and additional nonpoint source control efforts will be needed to further improve water quality in these lakes. The 1976–2004 trends for most water quality variables were similar at inlet versus outlet sites on Lake St. Croix. Trends at Lake Pepin inlet versus outlet sites were less similar, but data availability limited the comparison to the 1993–2003 period. While the truncated data record highlighted short-term trends in both lakes, the full data record was most useful for exploring general patterns in water quality. Length of monitoring record affected our ability to detect trends at the inlets to both lakes, and altered the magnitude of detected trends. During the two decades of the 1980s and 1990s, paleolimnological estimates of retained phosphorus loads were similar to those estimated from recent water quality monitoring. These similarities support the use of paleolimnological approaches to infer past water quality conditions in Lakes St. Croix and Pepin. This is one of eight papers dedicated to the “Recent Environmental History of the Upper Mississippi River” published in this special issue of the Journal of Paleolimnology. D. R. Engstrom served as guest editor of the special issue.  相似文献   
53.
在江苏沿海地区进行城市地质及水文地质等区域性地质调查,主要的野外工作手段就是全孔取心岩心钻探,但江苏沿海地区沉积层厚度300~500 m不等,最深处800 m之多。在如此之深的巨厚沉积层中钻探取心、且取心率要求之高在江苏乃至全国没有先例。结合某钻孔的施工实例,从钻探设备的选择、施工工艺的确定、泥浆控制技术等方面入手,全面总结了江苏沿海地区巨厚砂砾层全孔取心施工技术,对类似钻探项目的实施具有很好的借鉴作用。  相似文献   
54.
孙荣军 《探矿工程》2017,44(5):58-61
我国是采煤大国,大多数煤矿以井工开采为主,煤矿巷道掘进和支护的工程量很大,巷道支护钻孔施工需要消耗大量锚杆钻头,锚杆钻头的设计和制造技术也得到了快速发展。介绍了锚杆钻头的发展和应用现状,对我国煤矿现用的锚杆钻头的技术特点、适用性进行了分析,并结合煤矿巷道支护的实际需求,提出了施工硬岩和复杂地层时锚杆钻头存在的问题,最后从锚杆钻头设计、加工工艺等方面,阐述了锚杆钻头的发展趋势。  相似文献   
55.
张飞 《地质与勘探》2017,53(6):1188-1196
蓄能式绳索取心液动潜孔锤钻具是在普通绳索取心钻具总成上端增加了发生和传递冲击载荷的结构,将冲击载荷通过绳索取心钻具外管传递至钻头。新疆达坂城黑沟-达拉地布拉克铀矿工区裂隙、构造蚀变带和构造破碎带发育,地层破碎,使用普通绳索取心钻具钻进,岩心极易堵塞、回次进尺短、频繁打捞内管、钻进效率极低。使用蓄能式绳索取心液动潜孔锤钻具钻进,增加了回次进尺,提高了钻进效率。论文依据施工现场使用情况,介绍了蓄能式绳索取心液动潜孔锤的结构和工作原理,统计、总结了应用情况,论述了绳索取心液动潜孔锤得出的应用结论。  相似文献   
56.
Bionics was applied in the design of the impregnated diamond bit. Based on previous research and the 63# bit matrix formula, a new non-smooth bionic impregnated diamond bit with a single circular ring was designed and manufactured, and also tested indoor. The results were satisfactory. During its shape contacted surface system, non-smooth shape display some structure merits such as decreasing resistance. It was obvious that the drilling efficiency of the bionics bit is much higher than that of ordinary’s one, and so does the working life of bionic bit.  相似文献   
57.
为了提高金刚石钻头的时效和寿命,将钎焊法引入到高胎体金刚石钻头的设计和加工中。首先利用热压法加工耐磨性能好的金刚石孕镶块;然后加工自带两层水口和水槽的新型钻头钢体,且两水口之间预留焊接槽;最后采用钎焊法,将金刚石孕镶块焊接到钻头钢体上。野外试验表明,试制的2只Φ75/54.5 mm高胎体金刚石钻头,与现场使用的孕镶金刚石钻头相比,钻进效率分别提高41.7%和8.3%,使用寿命分别提高50.4%和32.9%。采用二次钎焊法加工的金刚石钻头,兼顾了热压法的优点,解决了工作层高度过高导致钻头胎体折断、掉块的难题,明显提高了金刚石钻头的使用寿命。  相似文献   
58.
通过冰芯研究可重建过去的气候环境变化, 为深刻理解现在和预测未来气候环境变化提供重要的科学依据. 冰芯机械钻机作为获取冰芯样品的必备工具之一, 在我国高山冰川冰芯获取中发挥了重要作用. 主要介绍我国自行研制的以山地冰川为主的冰芯机械钻机的发展过程和应用, 存在的问题和对未来的展望. 我国自行研制的BZXJ钻机性能优异, 是世界上同类钻机中的佼佼者, 截至2012年底已经钻取的冰芯总支数和总长度分别为125支和8 095 m, 为我国开展冰芯研究做出了重要贡献.  相似文献   
59.
Air DTH hammer has been successfully applied in minor-caliber solid mineral exploration,water-well drilling and other drilling areas.In order to expand the applications of the technology,the authors further studied the principle and analyzed the mechanism of reverse circulation drilling technique with air DTH hammer to get the perfect assembles of equipments by optimizing working parameters.No parameter seemed more important than the air volume because it could maintain the working performance stability.The minimum air volume is related to the parameters such as depth and pressure,which was calculated under the actual conditions.It was solved for the air injection flow tables of the air DTH Hammer working at the different pressures.According to the data tables,operators could adjust the air volume to meet the demand on this technique,which had a realistic guiding significance.So it could build up a set of systematic and complete hi-technique.  相似文献   
60.
基于Web的金刚石钻头模具钢体设计   总被引:3,自引:0,他引:3  
介绍了应用网页技术进行金刚石钻头模具钢体设计计算的方法。该方法丰富了模具钢体设计的远程教育,免去了传统人工求解的繁杂过程,界面友好,精度高,结果可靠,具有实际使用价值。   相似文献   
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