用竞选算法优化双万向轴的设计

用竞选算法来优化双万向轴的设计是以中间轴的外径和内径为设计变量,在传递转矩一定的情况下使中间轴的质量最小,并同时满足强度、刚度、振动条件、稳定性及边界条件的约束.实例计算表明,针对双万向轴的优化设计,用竞选算法可以较快地寻找出全局最优解.     

SSWZ330型十字轴万向联轴器的运动学分析

SSWZ330型十字轴万向联轴器广泛应用于重型机械中,但由于制造误差,常出现回转体质量不均衡现象,而产生较大的惯性力,严重影响了其使用寿命。利用CATIA对实际加工的零件进行三维实体造型,装配后导入ADAMS中,并对存在不平衡质量的联轴器进行运动仿真分析。针对变化的轴间角和工作负载,得出输入轴、中间轴及输出轴的角速度变化曲线和转矩运动曲线。通过分析得出万向联轴器出现问题的主要原因,为联轴器的后续加工和安装调试提供理论依据。     

挖掘机行走机构中间轴断轴原因分析

在生产运行中WK－4挖掘机的行走机构容易发生主动轮或中间轴断裂事故．其中间轴断型的原因有以下几种：（1）应力集中检查断裂的中间轴发现,断裂均产生在花键退刀槽处（尺寸为100mm）,即轴的最小截面处。并且,有时花键根部无退刀相或退刀槽过小,致使花键根部应力集中;（2）同心度差行走减速机4段轴是空心花键轴,如装配时与中间轴的中心线不重合时,中间轴不但要承受动力传动时的扭矩,还将承受一个与转动周期一致的弯曲应力,促使中间钻在退刀槽处断裂。预防断轴的措施：空心轴与中间轴装配时应容易安装,4段齿轮响合均匀,无倾斜,…     

十字轴式万向联轴器的运动仿真分析

介绍了十字轴式万向联轴器的运动特性,分别使用转角差、角速度比和转速不均匀系数表示单万向联轴器和双万向联轴器的转动波动性;重点分析了轴线夹角对单万向联轴器不等速传动、双万向联轴器等速传动和不等速传动的影响。仿真分析表明,减小轴线夹角且使两轴线夹角接近,能够有效保证双万向联轴器转动的平稳性。     

安装GAF系列轴流通风机的设计要求(下)

一、GAF系列卧式矿井轴流通风机中间轴校准的设计要求 GAF系列卧式矿井轴流通风机是通过中间轴和两侧的联轴器,将电动机的动力传递给风机的转动部件。 1.中间轴及联轴器的结构:该通风机的中间轴是空心结构,长度约8m左右。其两端各焊接法兰盘一个,以便与电动机端和风机轴承箱端的半刚挠性联轴器相联接,其间不再设轴承。 这种联轴器(图1)上的“8”字弹簧片是用螺栓对称地联接可折卸法兰盘及联轴器体     

利用中间轴作拆建塔绞车

建塔时向上运送塔材,拆塔时向下降放塔材都需要用较多人力,是一件笨重的体力劳动。可在开钻前或终孔停钻后,简单的改装中间轴,将一端的皮带轮用二个螺栓固定一卷筒,用轴上原     

SWC型整体叉头十字轴式万向联轴器的装配

根据十字轴式万向联轴器的结构特点 ,就万向节与轴叉孔的装配进行了分析 ,设计了一种辅助工装 ,改进了装配方法 ,提高了装配精度     

弯外管螺杆钻具装合差的测定方法

螺杆钻具偏斜钻进配备的偏斜器，目前有弯接头和弯外管两种。弯接头与定向接头设计为一整体，共属一条母线，不存在装合差，而弯外管是通过螺纹连接在万向轴节外管下端，定向接头则通过螺纹连接在旁通阀的上端，两者之间有万向轴节外管、定子、旁通阀3道螺纹相连，因此组装好的螺杆钻具之弯外管与定向接头的母线，很难处于同一条直线上，其差值     

WK—4挖掘机推压中间密封装置的固定

WK—4挖掘机的推压中间轴为一齿轮轴,为保证该轴的齿轮与大齿轮正常啮合的润滑及防尘,以及减速机构的装配需要,在齿轮轴的齿轮两侧设有密封装置,原设计中,该装置的定位是依靠减速箱盖上的定位螺栓(M10)     

螺杆钻具万向轴失效分析

对某厂生产的螺杆钻具万向轴失效原因进行了详细分析，指出此万向轴失效的主要原因是由于万向节花瓣部分接触面摩擦力过大，而所用材料热处理工艺不合理，造成硬度过低，耐磨性能太差造成的，并对此提出了相应的改进措施。     

China rare earth market review

正November 1~10,2014Chinese rare earth market was still inactive.Demand for rare earth products was weak.Consumers took a wait-and-see attitude for lower price.As it was an off season for rare earth products,it was expected that prices of rare earth could continue turbulence at the bottom in short terms.Due to a sharp drop,demand for rare earth from downstream recovered.Affected by new energy vehicles,wind powder and energy-efficient appliances,production of rare earth permanent     

China rare earth market review

正August 1~10,2014 There was some good news in rare earth industry recently.Restructuring plans of rare earth groups led by Baotou IronSteel Group and Xiamen Tungsten Group respectively have been approved by MIIT.And rare earth storage policy,which had been expected for a very long time,has been launched officially.Pushed by the good news,rare earth price started to rebound since August 5.Price of didymium oxide and dysprosium oxide rose about 1% to 2%,averagely.About 10% of     

China rare earth market review

正July 1~10,2014Due to weak demand from downstream industry and slow transactions,rare earth market remained weak and price of rare earth products continued to decline.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,     

New energy vehicle:an opportunity for rare earth magnets

<正>Extracted from Securities Guide 1.Popularity of new energy vehicles—an irresistible market trend1.1 Progress of new energy vehicles Chinese Premier Li Keqiang said recently on a visit to Xi'an BYD Autos that new energy vehicles,especially new energy bus,can lessen environment and noise pollution.He encouraged the use of new     

注浆加固技术在十三矿-685 m进风大巷中的应用

针对煤矿开采深度不断向深部延伸,掘进巷道受深部高应力的影响越来越大,巷道围岩整体稳定性差,矿山压力显现越剧烈现象,一般锚网喷加锚索支护无法从根本上控制巷道的变形。总结了平煤股份十三矿-685 m进风大巷注浆加固技术,依据对巷道掘进之后变形监测数据的采集,对巷道变形机理进行分析研究,并对注浆时段进行了合理选择,在对巷道的注浆工艺进行了充分论证的基础上,对巷道进行了注浆。注浆后效果表明:巷道滞后注浆时间段的选择非常重要,巷道在恰当的时间内进行注浆加固施工,能有效控制巷道的变形,巷道注浆后变形量明显减小,岩体的稳定性明显增强,减少了巷道日常维修工作,降低了矿井的生产成本,保障了矿井的安全生产。     

Brief news

正China Minmetals Rare Earth Construction of Jianghua Separation Plant is set to complete at the yearend Civil works of Jianghua Separation Plant have been finished and the company is installing and debugging equipments now.It is estimated that construction of Jianghua Separation Plant will be     

Brief news

正Total transactions of rare earth in Rare Earth Ex-change Center of Hunan South Rare and Precious Metal Exchange neared 40 billion yuan from January to October From the opening in January of this year to the end of October,the total transaction of rare earth products in Rare Earth Exchange Center of Hunan South Rare and Precious Metal Exchange neared40 billion yuan.There are 16 varieties including dysprosium oxide and terbium oxide traded on the exchange center,one of the largest trading platforms for rare earth oxides in China.     

Theoretical basis for optimal collector concentrations and pulp pH values during flotation of sulfide-free minerals

A hypothesis that associates optimal conditions of mineral flotation with a zero charge of their surface is put forward. This hypothesis serves as a basis for a methodology to obtain and verify quantitative physical-chemical models for a minimal necessary concentration of a collector during flotation of sulfide-free minerals. These models may be of use for upgrading engineering processes of flotation and as a job for the concentration plant automation systems. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 89–99, March–April, 2006.     

基于LPWAN技术的采煤沉陷区杆塔倾斜监测系统

随着地下采煤活动不断加大，越来越多的输电杆塔不可避免地被建设在煤矿沉陷区。目前，现有手段采用靠人力去进行定期检查一定会浪费大量的人力和物力，因而需开展对位于煤矿沉陷区的杆塔进行实时在线检测。基于NB-IoT和LoRa提出了一种新的算法——低功耗广域网（LPWAN）技术，提出了一种新型的输电杆塔倾斜监测系统，其中包含1个主节点和多个子节点，以适应地域广和远距离的需求信息监控。该系统通过LoRa多节点网络的数据传输，将杆塔的倾斜参数通过NB-IoT上传至在线实时监控系统。管理人员可以从后台得出监测数据并分析结果，及时对处于煤矿沉陷区的有故障的输电杆塔进行针对性的维护。     

基于AutoCAD的复杂曲线绘制的实现

介绍了如何利用其他软件在AutoCAD中精确绘制各种不同规划曲线的技巧 ,很好地解决了在AutoCAD中绘制多义线方法形成复杂曲线的误差问题 ,取得了较好的效果 ,具有实际意义。