基于ANSYS Workbench的球磨机筒壁减薄的有限元分析

本文在某球磨机结构特点和载荷形式的基础上,利用ANSYS Workbench软件对球磨机筒体进行了有限元分析,得出筒体的应力和变形分析结果,并根据分析结果对筒体的壁厚进行了适当的减薄,减薄后每台设备可节约钢材7570kg,且筒体的强度和刚度均能满足生产要求,节约了生产成本,验证了筒壁厚度减薄方法的可行性。分析结果表明,此分析方法适合进行球磨机筒体的应力及变形分析,可为同类型的球磨机提供一定分析依据和方法。     

球磨机回转体有限元分析

在某球磨机结构特点和载荷形式的基础上,指出以往采用的经验强度计算方法的不足.建立了该球磨机基于ANSYS的有限元模型,得出回转体在满载静止、启动和正常工作三种工况下的应力和变形分析结果,并对其加以比较得出分布规律,提供了给定设计方案的结构应力和变形。     

30吨陶瓷球磨机的有限元强度分析及尺寸优化

运用大型通用有限元软件ANSYS对大型的30吨陶瓷球磨机进行有限元分析,建立了球磨机的参数化模型,分析出整个球磨机平稳工作时的应力应变情况并进行了静强度和疲劳强度的校核,得出其强度足够且有较大的强度储备的结论.在此基础上,为节约生产成本,对球磨机的关键尺寸进行优化,得出了优化方案.     

陶瓷工业球磨机筒体结构形式的探讨

本介绍了球磨机功率消耗的设计计算新方法,并从球磨机的功率消耗、简体的机械强度和钢材消耗量及对物料的粉磨作用等方面论述了陶瓷丁业球磨机简体的理想结构形式应     

基于有限元分析的箱式换热器应力强度分析计算

利用ANSYS有限元分析软件,计算了箱式换热器的强度和刚度。并根据JB 4732-95《钢制压力容器-分析设计标准》,对计算结果进行线性化处理,分析应力最大点附近等5条截面路径的膜应力、膜应力加弯曲应力和总应力。分析计算结果表明,各应力均小于标准所要求的许用应力强度值,换热器强度满足要求。     

超高压蒸汽管线的强度核算及异径管小端裂纹的成因

对某厂超高压蒸汽（ＳＳ）管线的裂纹进行了强度校核。分别用等值刚度法ＦＡＯＰ及三维有限元法ＳＡＰ５Ｐ计算程序，对该管线进行了应力计算。结果表明，此管线的静强度足够。又用ＳＡＰ５Ｐ程序中８～２１节点等参单元，对在环焊缝处产生长裂纹的异径管进行了详细应力分析。给出了裂纹所在截面的轴向应力数值。并探讨了裂纹形成原因     

衬胶闪急蒸发器有限元应力分析

用有限元法对外方提供的衬胶闪急蒸发器钢壳体进行应力、位移等的详细计算和分析,并用应力分析方法校核该容器的强度。结果表明,在圆筒体与锥体连接处部分节点的名义应力已超过3[σ]。     

焊缝层数对不锈钢复合板残余应力和变形的影响

利用有限元法开发顺次耦合的弹塑性焊接残余应力有限元分析程序,对304不锈钢复合板补焊残余应力进行分析;在试验验证的基础上,讨论焊缝层数对残余应力的影响。计算结果表明,最大焊接残余应力出现在热影响区。由于覆材和基材强度的不匹配,在基材和覆材的界面产生了不连续的应力分布,对开裂影响很大。随着焊缝层数增加,变形增加,导致部分残余应力释放,使得残余应力降低。     

绕管式换热器管板的有限元应力分析与结构优化

绕管式换热器广泛应用于大型天然气液化装置,而管板是绕管式换热器的重要组成部件。由于管板处于管程、壳程交界处且布有密集的孔洞,降低了结构强度,使其成为LNG绕管式换热器的相对薄弱部位。利用Ansys有限元计算软件,对LNG绕管式换热器管板及其相连的管箱、换热器壳体进行整体建模和多工况下的有限元应力分析,并根据JB4732-1995进行强度校核。计算结果显示,换热器壳体对管箱短节部分的应力有较大影响;实例中换热器外壳的拉伸作用导致短节内侧局部薄膜应力过大,超出许用强度。增加短节厚度可以有效提高管箱强度;通过将原短节厚度由45 mm增加到57.5 mm,解决了局部薄膜应力过大的问题。     

应用SAP5程序进行间歇式球磨机筒体的强度分析

一、前言本文应用SAP5程序进行对间歇式球磨机筒体强度分析,既能处理厚壁园筒理论问题,也能解决薄壁园筒计算问题;使筒体强度分析更具有普遍意义,便于广泛采用.当前已采用均布载荷筒支梁方法计算,缺乏空间状态的位移和应力分布,且只计算静态,没有动态状况下的分析,失之偏颇而不全面.应用本方法可获得筒体的环向和径向的空间位移变形,以及静态,动态状况下的环向     

A Reliability Analysis Based on Fatigue Strength of Open-Mill Rollers

The two-roller mill is a basic processing machine in polymer industry, and the rollers are one of its important working parts. In the present paper, the working process of the mill roller used in plasticization of polymers and its failure mode is analyzed. The bending stress, shear stress, and resultant stress at the critical section of the mill roller are calculated to obtain its fatigue strength, and the corresponding diagram of fatigue limit graph is drawn. Based on the conclusion that fatigue failure is the main form of failure of the mill roller, a reliability analysis is applied to the fatigue strength of the mill roller and the reliability parameter is worked out. From example, it shows that the reliability of the mill roller is very high. Therefore, the working load may be increased appropriately.     

Grinding in an air classifier mill — Part I: Characterisation of the one-phase flow

In this and the related second paper [1], we present an in-depth study of the two-phase flow and the stressing conditions of particles in an air classifier hammer mill. This type of mill belongs to the mostly used mills at all. In order to develop a predictive grinding model not only the material's reaction to the applied stress but also the stressing conditions within the mill, e.g. impact velocity, incidence angle, number of stress events, have to be known. The latter are strongly affected by the interactions between the fluid and the solid phase within the mill. Systematic flow investigations in the vicinity of the impact elements and in the region of the internal classifier have been performed by Particle Image Velocimetry (PIV) and by numerical predictions of the fluid flow in the complete mill using a commercial CFD solver. Different pin geometries have been studied at various peripheral velocities of the grinding disk and the classifier. The classifier velocity does not influence the velocity profiles near the impact elements in the main flow direction and vice versa, the flow in the grinding zone has little influence on the classification. The velocity profile in front of the impact element, where the comminution process takes place, is constant with time and preserves a characteristic form independent of the operational conditions.     

氧化铝凝胶注模成形的研究

研究了Al2O3凝胶注模成形中浆料的流变性,素坯的强度、密度等随有机单体丙烯酰胺和Al2O3固含量的变化特性。实验采用L8(27)正交试验,并对各分散剂对屈服应力有显著影响,球磨时间主要影响流变指数。在120℃干燥后,凝胶注模后的素坯的强度可达到28—45MPa。随着有机单体丙烯酰胺的含量的增加,素坯强度上升,而随着Al2O3固含量的增加,素坯强度下降。在600℃热处理后,坯体相对密度为57—60%。随着有机单体含量和Al2O3固含量的增加,坯体密度表现为先上升后下降的趋势。     

1500m3球壳板曲率超标球罐有限元应力分析与强度校核

对1500m3曲率超标球罐在水压试验和设计压力工况下进行了有限元应力分析计算,并根据应力分析设计方法进行了强度校核。结果表明应力强度合格,但最大应力点偏移到超标曲率最大点处。参考应力分析计算结果,提出了球壳板曲率超标球罐的处理措施。     

A Stressing Model for the Description and Optimization of Grinding Processes

The comminution behavior of a mill is characterized by the frequency of stress events, and the stress energy, acting at each stress event. Based on this, a comminution result is determined by the number of stress events, and the stress intensity. The product of stress number and stress energy is proportional to the specific energy input. The proportionality factor is the energy transfer factor, which describes the percentage of energy that is used for stressing the product particles. Using the characteriztic numbers based on a few tests, the operating parameters can be optimized and different mills can be compared. The application of the stressing model is shown for stirred media mills.     

A reinforcing technique for the adhesive bonded composite joints using metallic wires

One of the strengthening methods of composite connection is the employment of reinforcing elements in the adhesive layer. Using of additional elements in the adhesive layer make uniform stress distribution and improves the strength and toughness of the connection. In this paper, metal wires were used to reinforce the adhesive joints of composites. The effects of the number of wires, wire diameter, wire stiffness, angle of wire and the adhesive type on the strength of the adhesive reinforced bonded composite joints were investigated experimentally and numerically. A finite element model was developed to study the stress distribution in the reinforced adhesive joints. The numerical results showed a good agreement with the experimental observation. It was found that increasing the number of wires and wire diameter, choosing a stiffer material for the wire and increasing the wire angle, uniform the stress distribution and reduced the maximum and average stress values in the adhesive layer. For the appropriate reinforcing wire parameters, the joint strength increased more than 90% in this study. It also observed that the using metal wires as a reinforcing element was more effective in the ductile adhesion than the brittle ones.     

Wet milling: A model based on hydrodynamics and particulate media mechanics

A mechanism for force transfer from the active tool surfaces of a mill to the particles in wet grinding is advanced. Use is made of the observation that in some mills a well defined gap develops between the active tool surfaces. Experimentally it can be demonstrated that a squeezing action on any slurry after an initial phase of slurry expulsion at constant concentration ($\text{oozing}$) results in an increase in the concentration in the squeezed zone, when only liquid is expelled ($\text{consolidation}$). The transition between these stages is discontinuous and can be understood from hydrodynamics and particle interaction. This phenomenon is shown to explain the formation of a distinct load carrying particle bed, apparent as the gap in wet milling.The resulting bed permits force transfer of the same nature as in a stressed particulate medium. Stresses in particulate media are transferred through stress chains forming a stress fabric. Stress concentration is a typical feature of such systems and is a function of the bulk. At sufficient load on the system one particle in this stress fabric will reach its limit of strength. The stress fabric simultaneously breaks down. The resulting denser system will on further compression develop another stress fabric with less stress concentration. Thus a higher load is required for the next particle failure. Eventually particle failure will stop. Mixing and shuffling the charge will result in new particle configurations with a high probability of higher bulk and higher stress concentration. In this new configuration particle failure will again be possible at low applied load to the system.The model explains the mechanims of bed formation in mills, the necessity of particle mixing for progressive particle failure and also identifies a neglected energy consumption factor in wet milling. An adaption of the model to dry milling is indicated.     

Ein Statistisch-Rheologisches modell der restfestigkeit geschädigten betons

The residual strength of damaged concrete having a structure similar to a pile of fragments is determined by the frictional resistance to slide of the elements. In the statistical-rheological model this fact is taken into consideration by connecting in parallel extended friction elements. Their load capacity can be expressed by a critical stress which is assumed to be at random in the system and can be described by a steady distribution. A criterion of stability is formulated as an unequation making it possible to compute the stress the system becomes unstable and fail s as well as the total strain at any load. Two examples - the stress-strain relation at elevated temperatures and the restriction of thermal expansion under non-steady state conditions - demonstrate efficiency and bounds of the model.     

新型废热锅炉高、低温管板试验研究

由于管板上开有众多的不连续通孔,因而其应力分布、强度问题十分复杂,为了弄清管板的受力状态,给废热锅炉管板的强度设计提供参考资料,在没有相应规范的情况下,本文对此新型废热锅炉的管板建立了试验模型,并进行了应力测定,实测结果和有限元计算值基本上接近。