【作者】 魏晓华；

【导师】 李贵轩；

【作者基本信息】 辽宁工程技术大学 ， 机械设计及理论， 2013， 博士

【摘要】 高效机械化掘进是保证矿井实现高产高效的必要条件，也是巷道掘进技术的发展方向。悬臂式掘进机作为巷道掘进主要设备，逐渐向着大功率、大机重、自动化方向发展。随之而来的是掘进机运行中的动力学问题更加突出，从而会对掘进机截割性能产生重要影响，根据掘进机的实际运行状况，掘进机的振动主要集中在截割头部位，因此研究截割过程的动力学特性，并依据动力学特性进行性能预测具有重要的实际意义。在系统归纳了国内外学者研究成果的基础上，分析截割过程的研究现状和不足，从而提出本文的研究内容，然后通过理论分析、数值仿真、现场实测和实验研究相结合的方法，对截割过程进行了深入的研究，主要研究内容和结论包括：1.在广泛分析镐齿岩石破碎机理的基础上，确认前苏联学者所用切削理论和切削力计算公式比较符合悬臂式掘进机截割头镐齿的截割状况，在此基础上，分别建立截齿与齿座之间无间隙振动模型和间隙非线性振动模型，并对考虑间隙非线性的振动模型应用Matlab进行了仿真研究，依据其动态响应确定出合理的截齿与齿座间隙范围，经过仿真分析和试验验证，可以为截齿与齿座间隙范围的确定提供一定的理论依据。2.根据掘进机的实际工况，在考虑到煤岩作用力的随机性、截齿间隙非线性、行星齿轮传动的非线性等影响因素的情况下，建立掘进机扭转振动的非线性动力学模型。该模型考虑了掘进机截割过程中的主要影响因素，为具体分析掘进机截割过程的动力学问题和性能预测提供了理论基础，经过数值仿真之后的数据与现场实测数据比较吻合。3.考虑机械结构部分和液压系统之间的耦合作用，通过静力学计算出升降油缸和摆动油缸在摆动截割过程中所需要提供的主动力，据此分析出摆动截割中回转台在升降和回转油缸共同作用下的回转振动情况，从而建立了掘进机摆动截割时的系统耦合动力学模型。4.对掘进机扭转振动的非线性模型进行了仿真分析，研究确定和随机煤岩作用力、不同工况参数匹配性等因素对于掘进机截割头的动态响应的影响。采用数值方法对各种因素影响下的动力学方程进行求解和仿真，得到截割头动态响应。通过和现场采集数据的对比，可以认为仿真模型比较接近实际情况。对掘进机摆动截割时的机械-液压耦合动力学模型进行数值仿真，依据仿真结果对摆动截割参数进行优化。5.通过对掘进机截割过程的非线性动力学模型进行仿真研究，应用仿真模型依据仿真结果进行掘进机性能预测。依据仿真结果，应用预测模型对掘进机的生产率、瞬时切削率和截齿消耗进行了预测，通过与现场实际数据对比，预测性能与现场数据比较接近，可以作为掘进机生产厂家和施工方进行性能预测的一种方法。6.通过截齿截割试验台进行截割实验。得到不同截割速度、不同间隙下截齿的截割规律，并与动力学模型的仿真结果进行比较分析。为准确确定掘进机截割阻力提供了依据。更多还原

【Abstract】 Efficient mechanized tunneling is an essential way for mining industry to achieve highproductivity and efficiency. It is also the trend of the roadway excavation technology. As majorroadway excavation equipment, boom-typed roadheaders (BTR) are being developed towards theintegration of high-power, large weight and automation. However, a problem associated with thistrend is the machine dynamic characteristics will become more prominent and thus has asignificant effect on the cutting performance of roadheader. Under different operating conditions,the problem of vibration is mainly caused by the cutting head of BTR. Therefore, it is importantto study the dynamics of its cutting process and to predict the performance which is based on themachine dynamic characteristics. The current research and its shortage are analysised on thebasis of the research achievement abroad and home. This paper presents a systematical way ofanalyzing the excavation process of BTR using a combined method of theoretical analysis,numerical simulation, field measurement and experimental studies which mainly include thefollowing contents and conclusions:Firstly, the breaking mechanism of BTR’s picks was analyzed in order to set up the cuttingtheory suitable for BTR and to determine a formula from Russion scholar to calculate the cuttingforces during its working process. Based on the established theory and the formula, a no-gapvibration model and a nonlinear gap vibration model were constructed. The nonlinear gapvibration model was then simulated using software package Matlab. The selection range of thegap value between the pick and the holder of BTR was decided according to the dynamicresponse of the model. The simulation results were validated with experiments and this can beused as a theoretical basis for determining the gap between the pick and the holder of BTR.Secondly, taking into account the randomness of the interaction force between coal androck under different operating conditions of BTR, nonlinearity of the gap between the pick andthe holder and the nonlinear factors of the planetary gear drive, the non-linear dynamic model oftorsional vibration was established. The model takes into consideration of the main affectingfactors in BTR and provides a theoretical basis for the dynamic analysis of its cutting processand performance prediction. Results show that the numerical simulation agrees well with thedata measured from experiment.Thirdly, the coupling effect between the mechanical structure parts and the hydraulicsystem of BTR were considered when calculating the required driving forces of the lift cylinders and swing cylinders in the process of swinging cutting using equations derived from solid statics.The results were then adopted to analyze the rotational vibration of the rotary cylinder in theprocess of lifting and turning during swing cutting. Accordingly, a system coupling dynamicmodel was established for BTR during its swing cutting process.Fourthly, a nonlinear model focusing on the torsional vibration of BTR was established andanalyzed. In addition, the effect of random coal rock force, different operating parametersmatching and other factors on the dynamic response of BTR’s cutting head was also studied anddetermined. Numerical methods were used to solve the kinetic equations under differentconditions and the dynamic response of the cutting head was derived through simulation. Thecomparison of the simulation results and the data collected in experiment implies that thesimulation model agrees well with real situation. Numerical simulation was carried out in themachinery-hydraulic coupling model of BTR during the swing cutting process. The results werethen used to optimize the swing cutting parameters.Fifthly, the study of the nonlinear kinetic model of BTR has resulted to the application ofsimulation results to the performance prediction of BTR. Based on these results, the prediction ofthe productivity, instantaneous cutting rate and cutter consumption has been realized. Bycomparing the results with the actual data, they have reached a high degree of agreement.Finally, different cutting speed and the cutting rules under different gap value between thepicks and its holder of BTR were obtained throughout experiments using a pick cutting testmachine. It was also compared with the simulation results from the dynamic model and this hasprovided an accurate and efficient way to determine the cutting force of BTR.更多还原