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中国年消耗锥体连接钎头1000万支以上,年消耗B_(22)、B_(25)锥体连接钎杆约15000t。针对中国钎具生产、使用部门在锥体连接问题上所存在的误解,结合修订和贯彻最新的钎头、钎杆国家标准GB6480t、GB6481,并参照国际标准ISO1718—1991,阐明了锥体连接的实质,充分论证了严格规定钎头锥孔和钎梢小端直径极限偏差值、孔底直壁间隙区、钎梢插深以及锥孔深度的必要性。这对减少钎具浪费、改善劳动条件、增强中国锥体连接钎具在国际市场的竞争能力,具重要的指导意义。 相似文献
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《探矿工程》杂志79年第1期介绍了我院钎头科研组提供的两种滑锤式卸钎器。其中,Ⅰ型卸钎器效果更好。Ⅰ型卸钎器原设计图纸基本可用,但经过半年多来生产实践的检验,证明其内部结构,仍需作某些改进。为了更好地在全国范围内加速消灭手锤卸钎,特将改进后的地院Ⅰ型滑锤式卸钎器详介如下。 相似文献
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在斜井、盲井、下山等掘进中,其打眼方向均为下向的,因此在凿岩过程中,由于客观条件的影响,卡钎事故较之一般为多。这不仅減少了純打眼时間,有时因被卡住的钎子无法拔掉而浪费了钎子鋼,并影响了炮眼排列的質量,以致大大降低爆破效果。因此在下向凿岩中,如何防止卡钎事故也是掘进工作中一个重要问题。根据我們在实际凿岩工作中的摸索,取得了以下几点经验: 一、做好凿岩前的准备工作。因为下向凿岩容易卡钎的主要原因之一,是由于工作面上有石碴与积水, 相似文献
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根据科技体制改革和发展新技术产业的有关精神,探矿工艺研究所与成都探矿机械厂在部有关部门负责同志的主持下,于去年达成了联合组建钎具研究所的协议,共同研制开发新型硬质合金钎具。 相似文献
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随着制造业不断向自动化、智能化方向发展,研究PDC钻头钎焊自动化是钻头生产技术的重点发展方向之一。为分析焊接强度对PDC自动化钎焊的影响及适应情况,利用特制的工装及试验条件,以PDC片和合金支柱为基体材料,开展了PDC高频感应焊接试验;并结合剪切强度和断面形态,分析了钎料钎剂、表面预处理、焊接方式、保温方式及感应加热对焊接强度的影响,并提出了适应PDC自动化钎焊的钎焊工艺方法。结果表明:应根据实际情况选取合适的银基钎料及专用焊膏;母材表面氧化层对焊接强度的影响较大;采用旋转式辅助焊接方式有助于钎料的铺展及排气排渣,能有效提高感应钎焊的强度;保温方式对PDC感应焊接强度的影响不大;应减小感应加热的集肤效应造成的边缘钎料熔蚀和中心温度低钎料未完全熔融对工件焊接强度的影响。研究结果为实现PDC自动化感应焊接提供了可行性方案,并对实现PDC钻头自动化钎焊提供了基础依据。 相似文献
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<正> 在实际勘探中,碳酸盐岩既可作为烃源岩,也可作为储集岩存在。确定碳酸盐岩中含有的烃类是原生的,还是从它处运移而来的,这在勘探实践中有着指导意义。为此目的,许怀先等用岩石热解分析方法做了大量研究工作。结果表明岩石中原油的热蒸发烃高峰温度和干酪根热解烃高峰温度具有显著差异:干酪根热解产烃高峰温度 T_(max)为400~600℃;原油热蒸发烃最高峰温度 T_(max)为300~400℃。由此可以区分原油的热蒸发烃和干酪根的热解烃,并进一步判定当最高热解峰温 T_(max)>400℃时,该岩石为烃源岩,而当T_(max)<400℃时,则为储集岩。对干酪根热解的进一步研究表明,不同成熟度的干酪根在不同的热降解温度范围内的产烃量是不同的。低成熟度的干酪根在450~600℃范围内所产生的烃占热解烃的5% 相似文献
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简要介绍了国内外扩底技术现状、扩底灌注桩的特点、MRR型基岩扩底钻头的结构衣技术参数,结合工程实例对MRR1000钻头的使用效果进行了分析。 相似文献
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JONATHAN SELBY 《Geology Today》1989,5(6):206-209
For years the world's most famous inselberg was plagued by the deleterious effects of human activity. Now a massive investment, stimulated by the international tourist industry, has ensured preservation of the rock's unique geomorphological features and its fragile ecology. 相似文献
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R. Resende L. N. Lamas J. V. Lemos R. Calçada 《Rock Mechanics and Rock Engineering》2010,43(6):741-761
The goal of this paper is to simulate the interaction of stress waves and rock fractures in a particle micromechanical model. Stress waves travelling in fractured rock masses are slowed down and attenuated by natural heterogeneities, voids, microcracks and, above all, by faults and fractures. Considerable laboratory and theoretical investigation have uncovered the major aspects of this phenomenon, but models that cover the core mechanisms of the wave propagation in rock masses are necessary to investigate aspects of wave–fracture interaction, which are not completely clear, and in the future simulate full-scale real problems. The micromechanical model is based on the particle discrete element model that reproduces rock through a densely packed non-structured assembly of 2D disks with point contacts. The model of a hard rock core is developed and an irregular rock joint is generated at mid-height. A new contact constitutive model is applied to the particles in the joint walls. Numerical static joint compression tests are performed and a typical hyperbolic stress–displacement curve is obtained. Conditions for good quality wave transmission through non-jointed unorganized particulate media are determined, hybrid static–dynamic boundary conditions are established and plane waves are emitted into the compressed joint. The transmitted and reflected waves are extracted and analysed. Joint dynamic stiffness calculated according to the hypotheses of the Displacement Discontinuity Theory shows to increase with the static joint compression until the joint is completely closed. Still in its early stages of application, this rock micromechanical model enables the joint behaviour under static and dynamic loading to be analysed in detail. Its advantages are the reproduction of the real mechanics of contact creation, evolution and destruction and the possibility of visualizing in detail the joint geometry changes, which is hard to accomplish in the laboratory. 相似文献
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《International Geology Review》2012,54(12):1408-1421
Density of volcano-sedimentary complexes progressively rises going down the Paleozoic section and decreases in the Precambrian. Density of the intrusive rocks is determined largely by their composition. There seem to be lateral changes in rock density, correlative with surface relief of the crust, differences in intensity of metamorphism, and intensity of dislocation. The density differences may be related to those in the degree of weathering or in the conditions, nature and intensity of metamorphism. --Author. 相似文献
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