Rigid multi-body kinematics of shovel crawler-formation interactions

Large capacity shovels are deployed in surface mining operations for achieving economic bulk production targets. These shovels use crawler tracks for effective terrain engagement in these environments. Shovel reliability, maintainability, availability and efficiency depend on the service life of the crawler tracks. In rugged and challenging terrains, crawler wear, tear, cracks and failure are extensive resulting in prolonged downtimes with severe economic implications. In particular, crawler shoe wear, tear, cracks and fatigue failures can be expensive in terms of maintenance costs and production losses. No fundamental research has been undertaken to understand the crawler-formation interactions in challenging and rugged terrains in surface mining operations. This study forms the foundations for providing long-term solutions to crawler failure problems. The kinematic equations governing the crawler-formation interactions have been formulated to characterise the crawler motions during shovel production. These equations capture the motions governing the link pin joint, oil sand terrain joint and driving constraints based on the multi-body rigid theory. Crawler propel is achieved by using prescribed velocities along a translational degree of freedom (DOF) and a translational and rotational DOF. The crawler kinematic solutions show that the 3-D crawler–terrain model results in 132 DOFs and requires dynamic modelling to obtain the unknown degrees of freedom. A 3-D virtual prototype model is built to capture the crawler-formation interaction in MSC ADAMS based on the rigid body crawler kinematics. The virtual prototype simulator is supplied with mass properties of crawler shoe, mass, stiffness and damping characteristics of oil sand and external loads due to machine weight and contact forces to obtain the time variation of position, velocity and acceleration for the crawler–terrain engagement for given driving constraints. The results from the driving constraints yield a non-linear longitudinal motion of the crawler track assembly. The crawler track lateral and vertical displacements during translation-only motion fluctuates with maximum magnitudes of 0.7 and 3.6 cm. Similarly the fluctuating longitudinal, lateral and vertical velocities and accelerations have maximum magnitudes of 0.22, 0.046 and 0.56 m/s and 7.41, 1.73, and 34.9 m/s², respectively. This research provides a strong foundation for further study on developing flexible crawler track model for predicting crawler shoes dynamic stress distributions, cracks development and propagation and fatigue analysis during shovel operations.     

单轨吊运输系统在大屯矿区的应用研究

针对大屯矿区各矿存在的采区人员机械化运输问题,结合矿井的实际条件,提出了"无极绳牵引单轨吊系统"、"防爆蓄电池电牵引单轨吊系统"2种采区人员运送方案。从技术性、使用与维护、经济性等方面对2个方案进行了比较和优选,最终确定采用无极绳牵引单轨吊系统,改造方案对类似矿井具有一定的借鉴意义。     

重介选煤厂管路磨损因素分析及耐磨措施

针对在重介质选煤过程中管路磨损严重的问题,从输送条件、输送物料性质和管路状况3个方面分析影响重介选煤厂管路磨损的主要因素,认为输送速度、攻角、磨粒粒度和形状、管壁材质以及内径等都会影响管路磨损。对于一般的直管,可采用普通的耐磨管路;对于弯管,可从耐磨材质的选择和设计合理的几何形状两方面着手。     

Simulation of Automated Dump Trucks for Large Scale Surface Mining Operations

Large-scale surface mining operations are increasingly employing large-capacity equipment for achieving economic bulk production. Syncrude and Suncor have recently acquired the CAT 797 (380-t rated) for oil sands haulage. The ownership and operating costs associated with these equipment are high, and thus, concrete efforts must be made to achieve reasonable returns on investors’ capital. In order to ensure high operating efficiency, research and technology have focused on automation and robotization applications in truck haulage. Automation and robotization of mining trucks present fundamental challenges in terms of off-highway truck dynamics. In this paper, the authors contribute to the body of knowledge by developing a robotization and stability control (RASC) model for operating dump trucks. The RASC model is developed using the Laplace and transfer functions. A FORTRAN-based simulation program, TRUX, has also been developed to facilitate the simulation and analysis of truck dynamics in the RASC model. The results show that the transfer functions of the front wheel, yaw rate and roll angle performed with respect to steering wheel angle yielded a good indication of automation. Simulated results compared well with test data with a significant peak ratio deviation in the first 5 seconds. Perturbations were observed in 5-20 sec range after which the system achieved stability.     

南芬露天矿延长290平硐服务年限的可行性研究

南芬露天矿坑底线已达到346m水平,按矿山改建设计的要求,290平硐矿石运输系统应停运,启和新的运输系统,新系统每年将增加约2千万 元的运输费用。为降低矿石运输成本,对延长290平硐服务年限的可行性进行了研究。研究内容包括地质调查、支护技术和露天开采综合技术等。研究结果表明,延长290平硐服务年限是可行的。     

基于3DMine的露天采矿设计

采矿设计是矿山建设和运营的一个关键环节。采矿设计需要综合考虑矿山资源状况、开采技术条件、矿产品销售价格、矿石开采及处理成本等多种因素,以实现经济效益最大化。目前三维矿床模型和采矿三维设计方法的完美结合使采矿设计更为简化,并可获得良好的动态效果。以利比里亚某铁矿为例,利用3Dmine三维矿业软件,建立了地表地形、矿体实体和块体模型。在此基础上进行了露天开采境界优化、开拓运输系统布置、采剥进度计划编制等采矿设计。结果直观反映了采矿设计方案及数据变化关系。同时讨论了不同矿石价格及不同台阶对露天境界的影响,分析了不同条件下剥采比的变化情况。在实际生产中,可根据不同情况适时调整露天开采境界,以实现最优的矿山经济效益。     

坐底式深海采矿系统力学分析

为了隔离中继站与软管及采矿车的相对运动,提出了一种坐底式深海采矿系统,建立了考虑波浪、海流等因素影响的采矿船、张紧器和输送管的全系统耦合分析模型,对各设计工况下张紧器张力、输送管等效应力以及挠性接头转角等参数进行了计算分析,结果均满足相关规范要求,验证了坐底式深海采矿系统的可行性和作业的安全性。     

Pipe lining abrasion testing for paste backfill operations

Pipe wear in paste backfill mining operations represents a great cost to mining companies. The replacement of prematurely worn pipes results in the shut down of the entire paste system. Abrasion testing performed on various pipe lining samples yielded both quantitative and qualitative data. Both standard and non-standard methods were explored during testing. The pipe materials are ranked by their relative wear resistance as well as energy per unit mass loss. The latter may allow for better prediction of pipe wear, this in turn could prove worthwhile when scheduling maintenance downtime for such a system where cost savings would be beneficial.     

端帮靠帮开采与搭桥内排相结合开采技术的应用

为了增加煤炭采出资源量和缩短内排土场运输距离,达到降低生产剥采比、提高经济效益和煤炭资源回收率的目的,根据河曲露天矿的开采条件,特提出端帮靠帮开采和工作帮与内排土场之间搭桥的开拓运输形式相结合的方法,主要研究不同搭桥高度产生的经济效益与靠帮开采产生的经济效益之和的对比,研究结果表明:在满足《露天矿设计规范》的前提下,靠帮开采将大幅提高经济效益,同时通过中间合适高度搭桥从技术上保证了运输系统的连贯性,验证了开采技术的有效性。     

桃山矿胶结充填管道输送系统充填试验

为了解决桃山矿三井工作面充填开采过程中出现的堵管以及管道的高磨损率等问题,运用流体力学理论,结合该工作面的实际情况,采用自流+泵送的管道输送技术进行了工业试验,并利用ANSYS模拟分析了在速度2.0 m/s时,不同料浆浓度、管径对全程管压的影响。模拟结果表明:既定输送速度下,在合理的可控范围内且易于输送时的充填料浆浓度、管径取值范围分别为52%、140~180 mm时,输送管压分别为134.561 kPa、130.053~138.759kPa。根据模拟结果进行的工业试验表明,堵管和高磨损率等问题得到了解决,充填开采取得良好的效果,有效地控制了顶底板的变形,降低了顶板的下沉量,减少对环境的破坏,验证了该管道输送系统是一种"安全、经济、环保、可靠"的充填采煤系统,为该矿以及类似条件下的矿山充填开采提供了借鉴。     

邻近层同采工作面动压巷道失稳机理及错距优化研究

针对邻近层同采工作面回采巷道受多次采动影响变形量大的问题,采用理论分析、数值模拟和现场实测的方法对邻近层同采工作面在走向和倾向上的不同错距进行了研究。结果表明:1)邻近层工作面同采过程中,上下两工作面间岩层受多重采动影响经历了连续—似连续—非连续—散体的过程;2)走向错距不同时,邻近层工作面支承压力峰值、围岩破坏范围和破坏程度由大到小依次为错距20 m、错距0 m、错距50 m、错距60 m;3)受多重采动影响,下工作面运输巷位移随工作面的临近呈现台阶式增加,经历了2次逐渐增加—明显增加—稳定的过程。采区设计应考虑邻近层工作面同采产生的多重采动影响,设计并优化得出合理的走向错距和倾向错距,改善工作面回采时采场围岩尤其是回采巷道围岩的力学状态。     

冬瓜山铜矿全尾矿输送技术研究

尾矿输送一直是大充填倍线充填矿山的难点,因此,通过对全尾砂料浆的环管试验,不同料浆浓度和不同流量(流速)和不同灰砂比料浆的多次输送试验,研究全尾矿料浆输送规律,分析试验结果,可以为提高充填质量,消除充填管路堵塞,加大尾矿充填量,降低充填成本寻找出一条新路。     

超长推进距离工作面双巷掘进的沿空顺采技术研究

运用理论分析与现场实测,研究了超长推进距离工作面双巷掘进的沿空顺采技术.首先,针对超长推进距离必须双巷掘进解决通风与辅助运输造成的保护煤柱留设较大问题,提出双巷掘进的沿空顺采技术.其次,结合双巷掘进、留窄煤柱护巷的技术要求,给出了如何确定双巷掘进之间的大煤柱、留窄煤柱护巷的小煤柱和沿空掘进工作面与首采工作面、接续工作面在推进方向的错距等方法.最后,提出在5000m超长推进距离下无法进行跳采的实际工程中应用该技术,给出了关键技术参数,认为该技术的实施不仅仅改善了巷道维护困难的现状,且两工作面之间可多采出1.01Mt煤炭资源,经济与社会效益显著.     

单台可伸缩带式输送机在长运距、多弯道运输巷的使用实践

针对综采工作面运输巷长运距、巷道弯曲等复杂地质条件下,需要安装多台带式输送机才能完成运输任务的情况,提出了通过使用高强度整芯输送带、选用自控液压张紧系统和变频控制等技术解决长运距运输的方案,同时根据现场综采运输巷道的实际弯曲程度,调整输送机落地架的两侧支腿的不同高度,解决了输送带在巷道弯曲点平稳运行难题。现已在东庞矿2612综采工作面运输巷实现了单台可伸缩带式输送机完成1 500 m运距、多点弯曲巷道的运输。     

Technical condition change detection using Anderson–Darling statistic approach for LHD machines – engine overheating problem

Abstract

In underground mine so called Load-Haul-Dump machines (LHD) plays a key role in horizontal transportation process. LHD machines execute ore haulage from mining faces to dumping points in a cyclic way. Time-varying and harsh environmental conditions determine high workload, so effectiveness demands are big challenges for maintenance staff. One of the most important issue is related to engine overheating, what is the main cause of unjustifiable loader stoppages and unwanted disturbances in production. Operator is obligated to react quickly and switch machine to idle operation until it cools down. Existing on-board monitoring systems dedicated for LHD machines provide data necessary to perform diagnostics of the engine as well as its cooling system. Understanding how load, wear level of machine and ambient temperature influence diagnostic data is the key in development of fault detection algorithms. In this paper, authors propose to use longterm temperature data. The Anderson–Darling statistic is applied in order to detect segments of different statistical properties which are related to different technical condition. Analysis of obtained two-dimensional data structure allows to find points of change of technical condition of the machine. It could be considered as training for diagnostic system that could be used for machine monitoring.     

1000 m深海采矿系统三维整体联动动态分析

1000m深海多金属结核开采试验系统的主体结构由采矿船、扬矿硬管、扬矿泵、中间仓、软管和集矿机等构成,系统各部分相互运动耦合。运用非线性有限元方法,将扬矿系统各部分等效为不同属性的管单元,建立了1000m海洋采矿试验系统整体联动分析的有限元模型,进行了系统整体联动的动力学数值模拟,得到不同联动模式下系统的运动特性与扬矿管的各种动态响应。研究结果表明：系统在设定的联动模式下以0．5m／s的速度联动时,中间仓的拖曳轨迹与船的运动轨迹基本一致;扬矿硬管上端水平作用力在转弯运动过程中变化较大,而垂直方向上的动态拉伸力呈稳定的交变力;扬矿硬管的弯曲应力较小,轴向应力较大。     

汽车－胶带输送机联合运输关键技术研究

汽车－胶带输送机联合运输工艺已成为露天矿剥采工艺的重要技术发展方向。其中，过渡深度、破碎站移设步距及开拓系统布置是该工艺的关键技术，通过分析组合台阶单位体的开采，以联合运输费用最小为原则推出了确定该参数的公式。实例研究证明了该方法的正确性和可操作性；汽车－胶带输送机联合工艺取代单一汽车（铁路）运输工艺可获得显著经济效益；联合运输工艺的选择与矿床赋存条件及露天矿全局的技术决策密切相关，应综合分析作出抉择。     

金属地下矿山井下移动式充填系统的应用研究

在深部开采的充填法中,如果采用传统的充填系统,可能会遇到充填管路较长、充填管铺设复杂、自流运输、充填浓度低、充填后的洗管水较多等一系列问题,而井下移动式充填系统为解决这些问题提供一个很好的思路。实践证明,井下移动式充填系统具有移动灵活、高压泵送、充填浓度高、工作效率高、成本低、管路铺设简单等优点。     

顶分层大采高综采架后高效铺网试验研究

针对松软围岩特厚煤层整层综放开采高含矸率、低回收率的问题，论文提出了“顶分层大采高综采架后高效铺网+下分层整层综放”开采方法，确定了顶分层大采高综采架后高效铺网的运网、挂网、展网、联网工艺，研发了工作面架后高效铺网材料运输系统、自动展网系统，并确定了架后高效联网方式，开展了高效铺网系统地面试验，对柔性网压缩效果、铺网运输系统、展网工序及快速联网时间进行了测试，以灵东煤矿为工程背景，分析了大采高综采架后高效铺网系统井下可行性。试验结果表明：大采高综采架后高效铺网运输系统拉移速度43.1～49.1m/min，联网速度1.33m/min，支架后方柔性网卷可顺利实现整体铺展，未出现网卷扭曲及紧缩现象，展网有效可行|大采高架后铺网整体工序作业时间为87.5min，工作面年产能力可达到600万t以上，能够实现工作面的高产高效。该试验成果对松软围岩特厚煤层高效高回收率开采具有重要的参考意义。     

某金矿高浓度料浆输送状态分析

某金矿采用充填采矿法,但随着开采的加深,千米深井高浓度料浆输送,管路设计布置等问题显现。本文就某金矿尾砂,胶凝材料性质进行分析,利用环管试验及生产中获得管路监测数据,通过公式验证加数据拟合方式,得出适合金矿及周边矿山工程计算应用的高浓度料浆输送阻力损失、流速等的分析公式。