煤矿巷道湿式混凝土喷射系统关键技术研究

发布时间：2018-04-18 20:37

本文选题：混凝土湿喷机 + 液压冲击　；参考：《中国矿业大学》2015年博士论文

【摘要】：煤矿巷道锚喷支护作业采用湿式混凝土喷射工艺能有效降低粉尘浓度和回弹率,研制能完成上料、配比、搅拌、输送和喷射等工序的湿式混凝土喷射系统,对于提高喷射混凝土的质量和生产效率、降低工人劳动强度具有非常重要的意义和广阔的应用前景。针对目前煤矿巷道湿式混凝土喷射系统研究中存在的湿喷机液压冲击大、喷射工艺参数选择无理论依据、湿喷机供料机械化程度低等问题,本文在以下几个方面进行了深入的研究。考虑泵送液压缸两端的缓冲结构,建立了混凝土湿喷机泵送液压系统数学模型和输送管道的负载特性模型,基于计算流体力学理论,利用FLUENT软件对泵送压力进行了模拟计算,根据零部件结构尺寸及性能参数设置了具体的仿真参数,利用MATLAB/Simulink软件对湿喷机泵送液压系统进行了数值模拟;通过仿真研究了换向阀切换时间、泵流量、油液弹性模量和节流阀结构参数等对泵送系统液压冲击的影响规律,在此基础上提出了湿喷机液压系统的改进方案。采用FLUENT软件,基于RNG型k-ε粘性流动模型,通过基于欧拉法的多相流流动模拟手段,对不同高压风入口风压以及混凝土喷射量工况下的空气与混凝土混合两相流场的速度及各相体积分数信息进行了仿真计算,掌握了风压、喷射流量等湿喷工艺参数对喷射流场特性的影响规律。开发了混凝土湿喷机供料系统,包括煤矿用砂石上料机和矿用混凝土搅拌机,并针对煤矿巷道内狭小空间的使用要求,对砂石上料机的抓斗和混凝土搅拌机的上料变幅装置进行了优化,解决了目前煤矿巷道混凝土湿喷采用人工供料效率低、工人劳动强度大等问题,实现了煤矿巷道混凝土湿喷机械化作业。研制了煤矿巷道湿式混凝土喷射系统样机,主要包括煤矿用砂石上料机、矿用混凝土搅拌机样机和改进后的SPB7型混凝土湿喷机,基于该系统提出了一种湿式混凝土喷射施工的工艺方法,并在煤矿井下开展了试验研究,结果表明煤矿巷道湿式混凝土喷射系统满足设计功能要求,系统内各设备间效率匹配,混凝土喷射施工效率明显提高,成本显著下降。
[Abstract]:The wet concrete spraying technology can effectively reduce the dust concentration and springback rate in the roadway bolting and shotcreting operation in coal mine. The wet concrete spraying system which can finish the processes of feeding, proportioning, mixing, conveying and spraying is developed.It is of great significance and broad application prospect to improve the quality and production efficiency of shotcrete and to reduce the labor intensity of workers.In view of the problems existing in the research of wet concrete spraying system in coal mine roadway, such as the large hydraulic impact of wet jet machine, the lack of theoretical basis for the selection of injection process parameters, and the low degree of mechanization of wet jet machine feeding, etc.This article has carried on the thorough research in the following several aspects.Considering the buffer structure at both ends of the pump hydraulic cylinder, the mathematical model of the pumping hydraulic system and the load characteristic model of the conveying pipe are established. Based on the theory of computational fluid dynamics, the pump pressure is simulated by using FLUENT software.The specific simulation parameters are set up according to the structural size and performance parameters of the parts, and the numerical simulation of the pump hydraulic system of the wet jet machine is carried out by using MATLAB/Simulink software, and the switching time of the reversing valve and the flow rate of the pump are studied by simulation.The influence of elastic modulus of oil and structure parameters of throttle valve on hydraulic impingement of pumping system is discussed. On the basis of this the improvement scheme of hydraulic system of wet jet machine is put forward.Based on RNG k- 蔚 viscous flow model and FLUENT software, the multiphase flow simulation method based on Euler method is presented.The velocity and volume fraction information of air and concrete mixed two-phase flow field under different high pressure inlet wind pressure and concrete spray rate are simulated and calculated, and the wind pressure is grasped.The effect of spray flow rate and other wet jet process parameters on the characteristics of jet flow field.The feeding system of wet concrete spraying machine is developed, which includes sand and stone feeder for coal mine and concrete mixer for coal mine, and aiming at the application requirements of narrow space in coal mine roadway.This paper optimizes the grabbing of sand and stone feeding machine and the feeding and changing amplitude device of concrete mixer, solves the problems of low artificial feeding efficiency and large labor intensity of wet spraying concrete in coal mine roadway at present.The mechanization of concrete wet spraying in coal mine roadway is realized.The prototype of wet concrete spraying system for coal mine roadway is developed, which mainly includes coal mine sand and stone feeder, mine concrete mixer and improved SPB7 type concrete wet spraying machine.Based on this system, a kind of wet concrete spray construction technology method is put forward, and the experimental research is carried out in the coal mine. The results show that the wet concrete spraying system in coal mine roadway meets the design function requirements, and the efficiency of each equipment in the system is matched.The efficiency of concrete shotcrete construction is obviously improved, and the cost is decreased significantly.
【学位授予单位】：中国矿业大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TD353.3

【相似文献】