Theoretical coupling longitudinal-transverse model and experimental verification of transverse vibration of rope for multi-rope friction hoisting system

Using the mass of time-varying length balance rope focused on the hoisting conveyance, the coupling longi- tudinal-transverse model of mine friction hoist was established by using of the Hamilton＇s principle. The modified Galerkin＇s method was used to discretize partial differential Eqs. The mine hoisting system was used to the example to analysis the relation between the load, velocity and transverse vibration of rope. The in situ tests were illustrated to evaluate the proposed mathematical model. The results showed that the modeling method can well represent the transverse vibration of rope.

Study on the instability of airflow in mine hoisting-shaf

In order to discover the airflow pattern in mine shaft which outfitted with hoist equipment （HE）, this paper set up the physical model and anatomized the piston-wind caused by hoist equipment, and researched the flow field and velocity field around the hoist equipment during its moving process, and analyzed the airflow around single and couple hoist equipment as well as decisive range of piston effect and additional effect of hoist equipment to ventilation system. Research conclusion indicate that during hoist equipment movement, airflow pattern changes repeatedly because of the influence of pis-ton effect from hoist equipment, and the study of airflow stability in shaft is the foundation for the stability of ventilation in mine.

Research on Energy Efficiency Characteristics of Mining Shovel Hoisting and Slewing System Driven by Hydraulic-Electric Hybrid System

Mining shovel is a crucial piece of equipment for high-efficiency production in open-pit mining and stands as one of the largest energy consumption sources in mining.However,substantial energy waste occurs during the descent of the hoisting system or the deceleration of the slewing platform.To reduce the energy loss,an innovative hydrau-lic-electric hybrid drive system is proposed,in which a hydraulic pump/motor connected with an accumulator is added to assist the electric motor to drive the hoisting system or slewing platform,recycling kinetic and potential energy.The utilization of the kinetic and potential energy reduces the energy loss and installed power of the min-ing shovel.Meanwhile,the reliability of the mining shovel pure electric drive system also can be increased.In this paper,the hydraulic-electric hybrid driving principle is introduced,a small-scale testbed is set up to verify the feasibil-ity of the system,and a co-simulation model of the proposed system is established to clarify the system operation and energy characteristics.The test and simulation results show that,by adopting the proposed system,compared with the traditional purely electric driving system,the peak power and energy consumption of the hoisting electric motor are reduced by 36.7%and 29.7%,respectively.Similarly,the slewing electric motor experiences a significant decrease in peak power by 86.9%and a reduction in energy consumption by 59.4%.The proposed system expands the application area of the hydraulic electric hybrid drive system and provides a reference for its application in over-sized and super heavy equipment.

Research on temperature rise of hoisting machine disk brake

A mathematical model and finite element model for analysis of temperature rise of the hoisting machine brake sys- tem was constructed, limit conditions were defined, and the law of temperature rise of brake shoes during emergent brake course was analyzed and calculated by using finite element software. By analyzing the calculation results, the law of tempera- ture change of surface of brake disk and shoes during the braking process was found. The law of brake shoes surface tempera- ture distribution and the law of temperature change along with thickness of brake shoes at brake time 0.5 s, 1.0 s and 1.5 s was analyzed. A hoisting machine emergent braking test was carried out. Finally, the author concluded that velocity rebound in the process of hoisting machine emergent brake is due to decreased friction coefficient caused by the temperature rise of the brake shoes surface.

Study of Movement Reliability for Hoisting Jack under a Rocket Launcher Vehicle

The transmission mechanism of a jack is required to support the combat vehicle reliably within a very short time. So reliability research is very important because the mechanism completes motions required under the conditions within limited time. If the transmission mechanism of the jack supports the rocket launcher steadily, it needs to go through several stages as follows ： unlocking, starting, operating, braking, stopping, fixing position and locking. The transmission mechanism of the jack is a complicated and single degree of freedom mechanical system; it can be considered an imaginary mechanical model that has an equivalent moment of inertia and equivalent torque. According to the characteristics of each supporting stages, dynamics equations of the mechanism are established. At the stages of starting and operating, a driving moment and resistance moment are dealt with for a Normal distribution. The design principles for movement reliability of completing action are established and the design principles for time reliability of completing action within a limited time are established. Finally, movement reliability of the transmission mechanism of the jack is 0. 9 852, according to our calculation. Reliability of time to complete action is 0. 9 943.

Water hammer in coarse grained solid liquid flows in hydraulic hoisting for ocean mining

The particles of polymetallic nodules in hydraulic hoisting flows that are used for mining in deep sea are rather coarse, therefore their flow velocity is smaller than that of the surrounding water. The characteristics of solid liquid flows such as their density, concentration, elastic modulus and resistance were discussed. The wave propagation speed and the continuity and momentum equations of water hammer in coarse grained solid liquid flows were theoretically derived, and a water hammer model for such flows was developed.

利用模拟退火技术求解多Hoist调度问题(英文)

多 Hoist调度在许多制造过程的设计与控制中是一个关键问题 .当 Hoist数与工作台数很大时 ,求解调度问题非常困难 .建立了多 Hoist调度问题的数学模型 ,并利用模拟退火算法提出了一种启发式求解方法 .随机模拟的大量算例表明 ,该启发式方法十分有效 。

基于有限元分析的液压启闭机稳定性折算系数研究

为了获得更符合实际的液压启闭机稳定性折算系数,文章系统分析了现有两端铰支液压启闭机等效力学模型和理论公式等,探究了适用于液压启闭机稳定性计算的有限元方法,并基于有限元计算结果提出了新的计算公式,进而分析了中部铰支液压启闭机临界载荷计算方法。研究表明:考虑油压作用于活塞的稳定性折算系数理论公式计算值与沿轴线方向施加油压的有限元计算结果相差较小,说明了该力学简化模型的合理性;基于油压始终垂直于活塞的有限元计算结果提出了新的稳定性折算系数计算公式;中部铰支液压启闭机可转化为铰点距相同的两端铰支模型计算临界载荷,液压启闭机临界载荷仅与活塞杆两端的约束有关。上述研究成果可为液压启闭机的设计及校核提供理论依据。

节段预制波形钢腹板组合箱梁桥节段 存放及吊装方案的优化设计

为了优化节段预制波形钢腹板组合箱梁桥节段划分、存放及吊装方案,以南京长江五桥引桥——立新路跨线桥为研究背景,采用数值模拟方法对波形钢腹板组合箱梁桥节段进行合理划分长度,分析标准节段梁存放及吊装期的应力变化及变形特征,并提出合理的控制措施.结果表明:节段长度为240~400 cm时,对梁体抗弯承载力影响较小,波形钢腹板组合箱梁桥节段长度的合理划分取决于吊装及运输条件;节段梁存放层数不宜超过2层,如采用双层存放,需在波形钢腹板节段梁混凝土顶板与底板之间设置临时刚性支撑;节段梁吊装宜采用四吊点方案,即在靠近腹板处设置4个吊点,且起吊时在顶板与底板之间设置临时刚性支撑,以避免顶板变形过大,增加现场拼装控制的难度.

房建工程装配式建筑结构外挂墙板施工技术

在我国建筑工业化进程中,以及“绿色建筑”概念的推动下,装配式建筑以其高效、低环境污染等优点,已成为建筑业发展的重要趋势。外墙板作为装配式建筑的核心部件,其建造工艺的优化直接关系到整个工程的质量与效率。以源平瑞璟花园装配式施工项目为例,针对建筑外立面墙板的特性,着重对外挂墙板的施工工艺进行了有针对性地分析。

地下工程预制梁钢筋骨架技术研究

随着地下工程施工对支撑结构质量和施工效率要求的提升,传统混凝土支撑结构施工质量和工期难以保障。预制梁钢筋骨架技术能够有效提高地下工程施工效率和质量,实现快速、标准化的施工流程,提高了施工效率,具有质量可控、施工风险低等优势。然而,该技术在发展中仍面临一些问题,包括技术标准不统一、设计与制造协作不够紧密、运输安装存在困难等。为解决这些问题,以南京市建宁西路过江通道项目为例,对预制梁钢筋骨架进行了标准化分段研究,研发了标准化制作台和超长预制梁钢筋骨架吊装对接技术。通过标准化分段、制作台研发和吊装对接标准的提出,为预制梁钢筋骨架技术的实际应用提供了高效、安全、可靠的技术方案,取得了显著效果。

新一代煤矿主井提升系统设计与在线检测技术应用

针对现代煤炭企业对即时监测和故障预警的迫切需求,设计一款主井提升载荷在线检测及故障诊断的系统。该系统包括检测、监测、自查、查询4个方面的功能,采用了高性能有机胶粘剂和耐磨有机涂层材料,增强了传感器安装的稳定性和关键零件的耐用性。对在线检测系统硬件和软件进行设计,并将所设计的提升载荷在线检测及故障诊断系统应用于实际的煤矿生产中,确保系统能够在恶劣矿井环境下的长期可靠运行。结果表明,提升载荷在线检测及故障诊断系统有效避免了各类故障,减少了主井的停机时间,有效确保主井提升系统的持续稳定运行。

应急离网工况矿井提升系统功率特性研究

随着越来越多的智能设备接入煤矿电网,煤矿的生产效益不断提高,各类大功率、非线性电力电子装置数量也随之增加,导致煤矿电网电能质量问题日益严重,因此,分析评价煤矿电能质量具有重要意义。对某煤矿6 kV副井提升机离网不同重载工况下的电能质量进行测试,利用电能质量分析仪对6 kV副井提升机所在母线电压、电流、功率、频率、谐波等电能质量指标进行在线监测记录,首次对所监测记录的3组离网重载工况进行定量评估分析,同时对测试中出现的一系列电能质量问题进行分析并提出相关建议,为煤矿储能装置应急电源的设计提供相关思路。

基于装配式建筑的施工技术创新研究

改革开放以来,社会经济高速增长,城镇化水平不断提升,我国建筑业得到了长足的发展,装配式建筑是建筑领域的新形态。以上海市公安局业务技术用房(陈行公路)项目为例,从测量放线、吊装施工、混凝土施工、灌浆套筒、绿色施工等方面,探讨了装配式建筑施工技术的创新,并提出了质量保证措施,为今后类似项目的建设提供了参考。

矿井提升系统纵向振动的磁流变阻尼器减振悬挂装置设计

为抑制矿井提升系统的纵向振动,设计了一种基于磁流变阻尼器的纵向振动减振悬挂装置。首先,建立了磁流变阻尼器力学模型,并对减振悬挂阻尼器进行了结构设计和磁路设计。其次,基于多物理场仿真软件COMSOL建立了磁流变阻尼器的多物理场耦合模型,在电磁场、流场的流-固耦合环境下分析了内部磁场、流场和压力分布状况,验证了机械结构和磁路分布设计的合理性。然后,通过耦合电磁场、流场和力场的动力学仿真,得到了磁流变阻尼器在正弦激励下的阻尼力F与位移x、频率f、振幅A、电流I和阻尼可调系数β之间的关系特性;仿真结果表明,在工作电流为0~1.4 A时,所设计阻尼器的最大阻尼力为4 993 N,最大阻尼可调系数为9.97。最后,试制样机验证了所设计的磁流变阻尼器可为减振悬挂装置提供所需的阻尼力,实现矿井提升系统纵向振动的抑制。

邻近电力隧道盾构吊装下井施工技术

为解决盾构吊装下井施工时近邻既有电力隧道的问题,结合重庆轨道交通15号线陈家桥站盾构始发工程,吊装前通过对履带吊作业区域换填0.3 m厚松沙,并采用0.5 m双层钢筋网片混凝土进行路面硬化的方式减小吊装荷载对下方电力管线的影响,吊装时通过在履带吊下方加垫0.04 m路基箱分散吊装过程中产生的附加荷载。结果表明:通过对履带吊吊装能力的计算确定了不同吊装部件选用的钢丝绳参数,吊装形式及其吊耳型号,计算结果均符合相关规范要求;通过对现场地基承载力的检测和计算,以及针对电力隧道进行安全验算,发现检测结果远远高于计算结果,表明加固后的吊装区域完全满足最不利工况吊装的安全要求。研究结果丰富了邻近电力隧道盾构吊装下井施工技术,也可为盾构吊装邻近既有构筑物的场地加固提供参考。

某项目栈桥板下方钢结构吊装施工技术

通过对栈桥板下方钢结构吊装施工工况进行深入分析与研究,结合施工过程中存在的重难点问题和施工过程中存在的不安全因素,提出了具体的应对措施,采用安全、实用的施工工艺,成功解决了栈桥板下方的钢结构吊装施工难的问题。相比传统栈桥板下方的钢结构施工方法,该技术具备安全性、适用性和可靠性,尤其适用于栈桥板下方钢结构的吊装施工,具有较强的行业推广意义。

基于窄带物联网的矿井提升机综合自动化控制系统设计

针对传统矿井提升机自动化系统存在实时性差、智能化程度低的问题,提出一种融合窄带物联网(NB-IoT)技术的综合自动化控制系统设计方案。该系统采用多层架构,集成了无线测振、温度、应变等传感器,可全面感知提升机的运行状态。通过NB-IoT网络进行可靠的数据传输,并在云端平台中应用SVM等智能算法,实现对系统的精准控制和故障诊断。结果表明,该系统在数据传输、实时控制、故障诊断等方面性能优异,能有效提升矿井提升机的智能化水平和运行安全性。