【作者】 何云华；

【导师】 白明华；

【作者基本信息】 燕山大学 ， 机械设计及理论， 2010， 博士

【摘要】 混合机和烧结机是烧结厂的核心设备,随着设备的大型化,高炉容积在不断扩大,大型高炉对含铁炉料的强度、粒度、化学成分,尤其是冶炼特性的要求越来越高。所以,生产优质烧结矿所需要的设备——混合设备和烧结设备的作用显得尤其重要。规模不断扩大的同时也出现很多问题:如混合机经过长时间的连续运转,机内物料粘结在其内壁,不易清除,物料混合制粒效果不好,橡胶轮胎磨损严重;烧结机漏风导致烧结矿质量下降、产量降低、返矿增多,能耗加大,直接影响到高炉的生产。针对上述问题,本文进行了如下研究工作:首先分析了混合机混合、制粒时物料的运动过程,对其内部物料运动的六种状态进行总结。找出影响圆筒混合机混匀、制粒的主要因素,对一次混合和二次混合时的最佳操作参数做了深入研究,使得工艺得到优化。其次对圆筒混合机筒体径向的力学性能进行分析,推导出径向受力的计算方程。研究了圆筒混合机筒体轴向受力情况,提出采用三弯矩方程,并结合轮胎受力与其径向位移之间的关系,建立方程组求解支撑轮胎的受力,这样得到的结果更符合实际。分析了筒体与轮胎之间的滑动摩擦力对轮胎磨损的影响,并给出计算实例。运用有限元软件ANSYS分析了总压力在各个支撑轮胎间的分配、轮胎的应力、应变和位移情况,得出了轮胎受力与轮胎径向位移之间的关系曲线。再次,分析了烧结机的系统漏风情况,描述了烧结机各个部位的密封形式及方法,首次提出对烧结机机头机尾采用风箱外高副接触头尾密封技术,风箱滑道采用磁液密封,并在国内几十家钢铁企业应用,经过长时间运行后测试密封效果,结果表明漏风率都有明显的下降,取得了良好的效果。最后,根据台车列辊轮轮距的交替变化,确定了星轮相隔布置的两类齿距,其中星轮的齿数为偶数。将啮合原理与星轮和辊轮啮合的具体工况相结合,建立了分段的星轮实际齿廓曲线,并将该分段曲线用统一方程表达。针对星轮在运行中出现的齿面损伤,应用赫兹接触理论对齿面接触应力进行了计算,并从多方面研究了提高星轮齿面承载能力的措施。采用非线性有限元对理想接触工况及实际接触工况进行了模拟分析,进一步揭示了齿面损伤产生的原因并证明了提高齿面承载能力所采用措施的有效性。在上述研究基础上,设计制造了新型带式烧结机的偶数齿数变齿距头尾星轮,有效解决了带式烧结机台车运行速度的波动问题,同时消除了下台车列部分起拱现象,提高其承载能力。更多还原

【Abstract】 Mixer and sintering machine is the core equipment of sintering plant. With the large-scale of equipment and increasing of blast furnace volume, the strength, particle size and chemical composition, especially smelting characteristics of charging including iron are called for increasingly high quality. Therefore, as necessary equipments of producing high quality sinter production, mixing and sintering equipments becomes particularly important. Constantly expanding scale of blast furnace causes many problems. After a long period of continuous operation, material in mixer sticks to inner wall and is difficult to be removed. Meanwhile, the granulating effects of mixed materials are very poor and sever wear of rubber tires occurs. Air leakage of sintering machine leads to a decline of sinter quality, decreasing of production and increasing of return fines ratio and energy consumption. So, it has a direct impact on the production of blast furnace.Aiming at above problems, research works were carried out as follows:Firstly, the movement of material during mixing and granulating was analyzed and it’s six motion states in mixer were summarized. Based on the influence factors analyzing for uniform mixing and granulating of drum mixer, optimal operation parameters of mixing and twice-mixing were lucubrated and the process was optimized.Secondly,the author analyzed the radial mechanical properties of mixing drum cylinder and derived from calculating method of radial force. Under analyzing axial force of cylinder of drum mixer, three-moment equation was proposed. Combined with the force of tire and its radial displacement, these equations used to solve the force of support tire were established. The results obtained by the method seem more tally to actual operation. Furthermore, the effects of sliding frictional force between cylinder and tire on wear also were analyzed and calculation example was given. Pressure distribution between all support tires, stress, strain, and displacement of tires were simulated with ANSYS. And the relation curve between force of tire and radial displacement was educed. Thirdly, by analyzing air leakage and seal forms of sinter machine, author presented the sealing technique of head and tail of sinter machine for the first time and magnetism-fluid sealing was utilized on the bellows chute. All the measures and technologies have been applied in tens of steel enterprises. After a long period of testing of sealing, air leakage rate has a obvious decreasing and a good effect was achieved.Finally, two kinds of teeth space arranged alternately and the even number of teeth are determined for the sprocket wheel according to the interval changed wheelbases of the rolling wheels in the pallet cars. By combining the meshing principle with the actual working condition between the sprocket wheel and the pallet cars, the practical tooth profile curve is established and expressed by universal equation. Aiming at the tooth surface damage of the sprocket wheel while working, the contact stress of the tooth surface is calculated by using the Hertz theory, and various measures to improve the load capacity of the sprocket wheel tooth surface are studied. The distributions of the contact stress simulated with nonlinear FEM in the ideal working condition and the actual working condition show further that the damage reasons of the tooth surface and prove the availability of the methods for improving the load capacity. Based on the study results mentioned above, the front and back sprocket wheels with even number of teeth, varying teeth space and high load capacity for new type sintering machine are designed and manufactured. The speed fluctuation of pallet cars of belt-type sinter machine was effectively solved. It is more important that the arch problem of lower pallet cars was also eliminated and bearing capacity was also increased.更多还原