二硫化钼锂基润滑脂在牙轮钻机回转减速器中的应用

大冶铁矿有KY-310和45-R两种型号的牙轮钻机,其回转减速器中的齿轮和轴承原采用30号机械油油池润滑。由于回转减速器主轴与钻杆直接连接进行穿孔作业,又因油池润滑并不是完全闭式的,所以,在穿孔作业中网转减速器在轴下端密封盖中的密封圈与钻杆连接器之间常常发生漏油,造成钻架,机棚顶及钻架平台油污染严重,且要频繁加油,油量消耗很     

全数字直流调速装置在牙轮钻机上的应用

采用先进的全数字直流调速装置改造牙轮钻机上的回转、提升／行走控制部分,代替原来的磁放大移相脉冲触发可控硅整流系统 。     

45R牙轮钻回转电机磁极线圈固定方式改进、节约资金3.83万元

牙轮钻机是矿山的主体设备,常因回转电机出故障而不能作业,同时外委修一台回转电机需1471元,平均半个月就要修一台回转电机,不仅浪费大量资金,还严重影响生产,为解决这一生产中的老大难问题,齐大山铁矿机动车间组织科技人员进行技术攻关,找出牙轮钻回转电机经常出故障的原因是回转电机的磁极线圈原设计固定方式有缺陷,使线圈固定不住,同时,电机运行中振动较大,线圈和铁芯之     

白云鄂博西矿岩石可钻性试验研究

岩石可钻性分级是矿山合理组织生产、提高劳动工效的重要指标,采用正确的岩石可钻性分级方法进行分级是露天开采矿山迫切需要的。针对白云鄂博西矿分布复杂、变质化的火成岩进行了全范围有代表性的取样及物理力学特性试验;开展了牙轮钻穿凿各种岩体的现场测试。研究结果表明,矿岩的可钻性与物理力学特性具有很好的相关性。     

KY—310牙轮钻机稳车千斤顶下沉的浅析与处理

1.下沉故障及后果 大冶铁矿有两台KY—310牙轮钻机,每台采用四个液压千斤顶油缸稳车。在实际使用过程中,当千斤顶升起钻机并调平稳车之后,两台钻机千斤顶油缸都有下沉     

交流调压调速在矿山牙轮钻上的应用

在进口牙轮钻上用启动转矩大的绕线式异步电动机(无调速)取代原损坏的交流双定子电机调速。此种电机采用转速、电流双闭环的交流调压调速系统,其应用的触发器集成度高、可靠性强,通过现场使用表明:牙轮钻工作可靠、维护方便,提高了生产率,深受现场工程技术人员和工人师傅的好评。     

基于Cosmos/Works的牙轮钻机钻架结构强度分析

应用Solid/Works软件建立牙轮钻机钻架的三维模型,利用与Solid/Woks无缝集成的快速有限元分析软件Cosmos/Works方便、快速、准确地对钻架进行强度分析与校核.     

YZ-35牙轮钻机润滑故障的分析与对策

针对YZ-35牙轮钻机集中润滑系统和回转减速箱常见的润滑故障，结合实际修理情况，分析故障产生的原因，介绍判断故障的方法，提出结构的改进措施和修理中应注意的事项。     

KY-200B牙轮钻机远程控制升级改造

随着5G技术的不断推广、在工业上的应用不断成熟,智慧矿山、数字化矿山迅速发展,传统的牙轮钻作业与现代信息技术相结合,催生了远程集中控制钻机穿孔产业,通过对KY-200B牙轮钻精准定位、测深系统及自动接卸杆等各系统改造,利用5G数据传输及远程控制优势,实现远程操作生产,为数字化智慧矿山提供硬件支持。     

45-R牙轮钻机钻架及回转减速器的改进

45-R牙轮钻机在我国一些大型冶金矿山中已使用10余年。生产实践表明,当它在较高硬度(f>16)的矿岩中作业时,其主要工作部件——钻架和回转减速器不能适应生产作业要求。对这薄弱环节,人们一直在探讨改进的办法。 1.存在的主要问题 1.1钻架 从我矿使用情况看,钻架的主要问题是整体刚度不够,因而在穿孔作业中变形较大     

变频调速系统挖掘机提升机构失控故障浅析

以变频调速系统大型矿用挖掘机为研究对象，介绍了电铲两台提升电机间存在机械耦合，所以两 台逆变器之间采用转矩主从控制方式，其中主装置（MASTER）为速度控制，从装置（SLAVE）为转矩控制， 这样提升机构既实现速度控制，又保证两台电机间的出力均衡的工作原理。分析了提升失控问题的各种可能原 因以及应对措施，确保设备可靠运行。     

Theory of Seepage into an Auger Hole in a Confined Aquifer Overlying a Gravel Substratum

An analytical solution is presented to the problem of steady groundwater flow seeping into a pumped cylindrical hole partially penetrating a homogeneous and anisotropic confined aquifer overlying a gravel substratum. Solutions are obtained for two general cases of the problem: (1) when the level of the pumped hole is below the confining layer; (2) when it is above it. The validity of the proposed theory is tested by comparing analytical predictions obtained for a few flow situations with corresponding results obtained by numerical means. The theory presented here can be utilized to convert the rate of rise of water in a pumped auger hole into directional conductivities of soil, in areas where water is found to be in a confined state overlying a gravel substratum. The study shows that the conductivity values calculated by neglecting the confining pressure of an artesian aquifer with a gravel base [i.e., by applying the existing (Boast and Kirkham in 1971), auger hole seepage theory for a phreatic aquifer with a gravel base to confined situations] may result in serious error; hence, the artesian head of an aquifer must be accounted for while computing the conductivity values. Further, it is observed that the area contributing flow to a pumped auger hole/well with a gravel base is mostly restricted to a short radial distance from the center of the hole, particularly for situations where the gravel substratum is located close to the bottom of the hole. This is in contrast to auger hole flow situations overlying an impervious substratum, where the domain contributing flow is mostly spread out to a considerable distance from the center of the hole.     

Theory of Seepage into an Auger Hole in a Confined Aquifer

A steady-state theory is presented for predicting flow into an auger hole partially penetrating a homogeneous and anisotropic confined aquifer that is underlain by an impermeable layer. The developed equations can be directly applied (i.e., without resorting to a coordinate transformation) to translate the rate of rise of the water in a pumped auger hole into directional conductivities of soil. The study shows that the conductivity values calculated by neglecting the confining pressure of an artesian aquifer (i.e., by applying the existing unconfined auger-hole seepage theories to experimental auger data obtained from a confined aquifer) may lead to serious error; hence, the confining head of an aquifer must be considered while the conductivity values are computed. Further, the distance of the outer layer also plays an important role in determining the flow to an auger hole penetrating a confined aquifer, and this parameter must therefore be included in the theoretical analysis of the problem. The validity of the proposed theory is checked by comparing a few results obtained from the theory with corresponding results obtained from numerical and analytical works. The developed theory is an addition to already existing auger-hole seepage theories for water-table aquifers; together with the available theories, the proposed solution is expected to cover the most commonly encountered auger hole experimental flow situations in the field.     

鞍钢大型厂直流电机节能技术

介绍了一种基于SIEMENS 6RA70系列全数字直流调速装置控制系统。系统采用PROFIBUS DP通讯实现PLC与6RA70系列装置之间的数据传输,以PROFIBUS DP现场总线控制方式,自动检测生产过程中直流电机停止运行的大量而短暂的间歇期间,能够自动减少励磁电流。经测算,直流电机励磁电流自动减少50%,每天降低电能消耗5%以上。     

Substrates for protein kinase CK2 in insulin receptor preparations from rat liver membranes: identification of a 210-kDa protein substrate as the dimeric form of endoplasmin

The cytoskeleton is essential for the proper function of many components of secretory and endocytic pathways, and the importance both of microtubule motors (kinesins and dyneins) and of actin motors (myosins) in these pathways is becoming apparent. Recent experiments have improved our understanding of which members of these motor protein families are involved in membrane traffic. Multiple motors are probably involved in the control of the morphology and dynamics of many membranes, and intriguing hints about how these motors are coordinated are appearing.     

同步电动机全数字励磁装置改造

文章介绍了同步机励磁控制系统,通过励磁装置改造,能够实现电机启动过程中的转子滑差控制,电机的失步检测和保护,准确灭磁等功能。改造后的励磁控制系统具有可靠性好,控制精度高,现场使用和维护方便等优点。     

西门子S120卸料块伺服控制系统的改造

Φ159 mm生产线冷床上料卸料块是在线设备,卸料块原控制系统采用2台丹佛斯FC302变频器通过主从控制方式来控制2台丹佛斯伺服电机。原控制系统比较复杂,维护难度较大,备件订购周期长,因此制定了应用西门子S120主从控制替代原控制系统的方案。改造后效果明显,既满足了生产需要又便于维护,并且实现了现场设备的备件统一。     

Pierre Auger--a life in the service of science

A short biography of Pierre Auger, the discoverer of the atomic auger electron effect, is given. Professor Auger's outstanding professional career covered physics, nuclear power and space research, organization and administration of research, diplomatic services and pedagogics but also extended into modern biology, humanistic sciences, poetry and arts. Part of a speech in Paris of professor Auger held in 1989 on the theme 'Research and Creativity' at an international symposium on the auger effect is included in this biography as well as one of his poems.     

开关磁阻电机调速系统在空压机、渣浆泵中的应用

高效节能电机与普通电机的功率等级及安装尺寸相同,所不同的是开关磁阻电机调速系统损耗低,效率高,缺相不烧电机。用高效节能电机是从根本上实现节能的最佳途径。     

变频调速与传统调速方式在我厂提升装置上的应用比较

鉴于传统电机调速方式暴露出来的电气设备易老化、电机机械特性软、能源损耗大等弊端,寻求一种全新的电机调速方式将成为必然趋势。随着变频技术的日益成熟,以及变频调速的带负载能力强、启动力矩大、实现电机软启动、输出恒转矩、可实现电机无级调速、电流冲击小、加减速过程平滑等优点,使变频调速在提升装置上的应用越来越得到认可,变频调速最终将代替传统调速方式来控制提升电机的运行。