一种机械压力机湿式离合制动器窜油问题分析

近几年来,湿式离合制动器基本取代了干式离合制动器,在机械压力机上应用越来越广泛。湿式离合制动器具有占用空间小、制动角稳定、惯量低、噪音小、啮合／松脱速度快、环境不会受到油雾和摩擦盘粉尘影响等显著特点,且在很大程度上无需维修,减少备件并节省能耗,湿式离合制动器因上述优异特性而得到用户的一致认可。     

压力机中组合式离合制动器的正确选用

介绍离合制动器的工作原理及其如何计算机械压力机所需的离合扭矩和制动扭矩.通过对机械压力机离合扭矩和制动扭矩的计算及其对离合制动器离合扭矩和制动扭矩校核,来准确的选择组合式离合制动器的参数及型号.     

湿式离合制动器在热模锻压力机上的应用现状分析

热模锻压力机上广泛应用的湿式离合制动器按离合器与制动器的布置形式可以分为分体式离合制动器和组合式离合制动器。湿式离合制动器以液压油作为工作介质,整个离合器、摩擦器腔内充满了液压油,主动轴和被动轴间的扭矩传递通过油膜间的抗剪力实现。本文着重介绍当前热模锻压力机上应用的湿式离合制动器的结构类型及相关产品,并对其关键零部件摩擦片的研究现状进行了归纳分析。     

伊顿公司推出金属加工业用离合制动器——Airflex(R) AMCB AccuStopTM离合制动器,扭矩稳定,维护简便

全球领先的多元化工业产品制造商伊顿公司今日宣布:公司Airflex(R)事业部推出金属加工行业用组合式离合制动器Airflex (R) AMCB AccuStopTM.Airflex (R) AMCB AccuStopTM离合制动器为金属加工业度身定做,适用于现有及新型机械压机驱动系统.     

基于模糊理论的高速冲床可靠性分配

针对高速冲床可靠性分配中存在的模糊性因素,提出一种依赖于专家知识的高速冲床模糊可靠性分配方法.利用三角模糊数量化模糊信息,应用多级模糊综合评判结合层次分析法综合评估各待分配子系统的相对可靠性水平,然后依此对高速冲床的可靠性指标进行线性分配.该方法能综合考虑各种可靠性影响因素及其模糊性,尤其适用于高速冲床这种复杂产品初始...     

浅谈高速冲床机械故障的处理方法

高速冲床在机械和塑胶零部件生产企业中大量应用,冲床出现各种各样的故障将严重影响企业的生产效率和经济效益。针对这些情况,在阐述了冲床工作原理的基础上,结合实际工作经验,研究冲床出现各种故障的部位,并提出修复故障的措施。对于高速压力机的使用维修具有一定的参考价值。     

强制循环冷却湿式气动摩擦离合制动器

强制循环冷却湿式气动摩擦离合制动器是在油浸式湿式气动摩擦离合制动器的基础上发展而成的,适用于公称力较大的高性能开式固定台压力机。 1.结构强制循环冷却湿式气动摩擦离合制动器的结构见图。离合器4和制动器5布置在飞轮3内。     

伊顿公司推出金属加工业用离合制动器——Airflex AMCB AccuStop^TM离合制动器，扭矩稳定，维护简便

全球领先的多元化工业产品制造商伊顿公司今日宣布：公司Aifflex 事业部推出金属加工行业用组合式离合制动器Airflex AMCB AccuStop^TM。Airflex AMCB AccuStop^TM离合制动器为金属加工业度身定做，适用于现有及新型机械压机驱动系统。产品按照IS09001质量体系制造，符合ANSI B1．1以及中国有关金属加工业的相关行业标准。     

机械压力机离合制动器摩擦块智能测控设计技术

机械压力机的离合制动器是压力机的主要部件之一,本文所述机械压力机离合制动器摩擦块智能测控装置中的摩擦块磨损量检测控制系统、传动轴旋转角度检测控制系统、摩擦块更换报警控制系统可以准确及时自动检测控制离合制动器摩擦块磨损情况,降低了对工人专业知识的要求,并且能提升产品质量,能更好满足机械压力机自动化生产线的智能化需要。     

电磁离合制动器KGD2型控制电源的研究

1．前言电磁离合制动器是一种组合式多功能产品．它由离合器和制动器组合而成，广泛用于机械传动系统中。其输入轴与电动机连接，正常工作时，处于连续旋转状态，输出轴与生产机械连接，见图1。当制动器线断电离合器线圈通电时，输出轴旋转时，对工件加工或完成某种机械动作，加工完成后，离合器断电，制动器通电，输出轴迅速制动注。离合制动器是当前自动化生产过程中不可缺少的电器元件。离合器线圈和制动器线圈不能同时通电，要有一定的间隔时间，为减小离合制动器的动作时间，提高生产效率和产品质量，在离合器线圈或制动器线圈开始通电…     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

Thermodynamics Study on the Decomposition of Chromite with KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

Influence of Heat Treatment on Damping Behaviour of the Magnesium Wrought Alloy AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching–Partitioning–Tempering Steels

The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.     

Growth Kinetics of Single Inclusion Particle in Molten Melts

On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes＇ collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.     

Theoretical Analysis for the Motion and Temperature of Melt Droplets in Spray Degassing Process

The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.     

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates(50 mm thick) by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS software.Considering the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement method.Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint.The peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.     

Microstructures and Tensile Properties of Ultrafine-Grained Ni–(1–3.5) wt% SiC_(NP) Composites Prepared by a Powder Metallurgy Route

Silicon carbide nanoparticle-reinforced nickel-based composites(Ni–Si CNP),with a Si CNPcontent ranged from1 to 3.5 wt%,were prepared using mechanical alloying and spark plasma sintering.In addition,unreinforced pure nickel samples were also prepared for comparative purposes.To characterize the microstructural properties of both the unreinforced pure nickel and the Ni–Si CNPcomposites transmission electron microscopy(TEM) was used,while their mechanical behavior was investigated using the Vickers pyramid method for hardness measurements and a universal tensile testing machine for tensile tests.TEM results showed an array of dislocation lines decorated in the sintered pure nickel sample,whereas,for the Ni–Si CNPcomposites,the presence of nano-dispersed Si CNPand twinning crystals was observed.These homogeneously distributed Si CNPwere found located either within the matrix,between twins or on grain boundaries.For the Ni–Si CNPcomposites,coerced coarsening of the Si CNPassembly occurred with increasing Si CNPcontent.Furthermore,the grain sizes of the Ni–Si CNPcomposites were much finer than that of the unreinforced pure nickel,which was considered to be due to the composite ball milling process.In all cases,the Ni–Si CNPcomposites showed higher strengths and hardness values than the unreinforced pure nickel,likely due to a combination of dispersion strengthening(Orowan effects) and particle strengthening(Hall–Petch effects).For the Ni–Si CNPcomposites,the strength increased initially and then decreased as a function of Si CNPcontent,whereas their elongation percentages decreased linearly.Compared to all materials tested,the Ni–Si CNPcomposite containing 1.5% Si C was found more superior considering both their strength and plastic properties.