50MN挤压机张力柱的断裂修复

分析50MN挤压机张力柱的断裂原因,介绍采用埋弧自动焊焊接修复大型工件的工艺过程、焊接采取的措施,以及焊接修复后张力柱的强度校核。     

预应力钢丝的生产与展望

1预应力钢丝的应用预应力钢丝应用干预应力钢筋混凝土结构，此种结构始干本世纪20年代。混凝土本身具有很高的抗压强度，但抗拉强度却很低，当受到拉力发生0．001％的变形时，混凝土即出现裂纹。若在混凝土中配以钢筋即构成钢筋混凝土。由于钢筋具有较高的抗拉强度．故钢筋混凝土结构既耐压又抗拉，被建筑业广泛采用。预应力钢筋混凝土结构又与普通钢筋混凝土结构有所不同。预应力钢筋混凝土结构采用预应力钢丝为筋（另一种是采用经热处理的热轧螺纹钢筋为筋，不在本文叙述之列），在混凝土制造之前，先在钢丝两端施加一定的拉力，然后浇灌…     

局部单层浅网壳的设计分析

局部单层浅网壳的设计关键在于在满足网壳刚度与整体稳定的条件下,确定经济合理的单层部分的可能布置区域和面积。为了满足网壳的刚度与整体稳定,施加预应力是一种常用且有效的方法,而预应力的施加对网壳单层部分的确定有直接影响。本文通过分析比较,寻找单层部分范围和预应力值之间的相对关系。     

公路桥梁加固采用体外预应力方法的探讨

桥梁结构在使用期间受环境因素的影响,材料将逐渐产生劣化,性能下降因车辆超载等因素也使建成后的桥梁出现不同程度的损伤甚至痛害.有些病害严重的桥梁已经不能正常运营,因此必须对其进行加固与修复.体外预应力方法,是将预应力钢筋布置于梁体截面外,并通过锚固块及转向块来对桥梁结构施加预应力的一种加固结构体系.本文根据多年的桥梁加固设计工作经验,介绍了采用体外预应力法加固桥梁在设计方面所应注意的问题,并通过典型案例分析,为推广体外预应力加固同类桥梁提出了借鉴.     

液压切头剪切机张力柱的设计计算

本文详细介绍了液压切头剪切机张力柱的预紧力和应力计算方法以及疲劳强度的校核方法。     

德国Hydro铝公司安装大型挤压机

德国SMS Eumuco公司为 Hydro铝公司Haufss铝加工厂提供一台65/70MN的自动化挤压机,该挤压机在设计上具有如下特性: 1.安全、可靠、快速的工作行程; 2.高的可再现性的产品质量; 3.低的生产费用。 强大的挤压机油压系统,停机时间短,并可保证挤压机平稳地加速或减速。借助于CADEX控制技术,使主挤压时间最短、且能在等温挤压过程中施加     

乌海市地税局工程预应力梁施工技术

文章介绍乌海市地税局大楼副楼预应力梁后张法的预应力筋制作,孔道的安装,预应力张拉,孔道灌浆等施工技术,以及施工方法和注意事项进行了阐述。     

预应力混凝土用钢棒的研究现状

预应力混凝土用钢棒由于其特点明显,在中国建筑、水利行业得到了广泛的应用。从原料使用、冶炼工艺、轧制工艺方面介绍了国内外预应力混凝土用钢棒的现状,并进行了分析对比;介绍了连铸-连轧以及深加工中的新技术;分析了中国目前预应力混凝土用钢棒发展存在的问题和所遇到的瓶颈。针对中国预应力混凝土用钢棒的未来发展做了相关分析。     

论预应力技术在建筑工程中的应用

通过对各种预应力结构形式的分类说明,和对预应力平板结构优点的重点阐述,分析和比较预应力结构的竞争力所在及其适用范围,达到预应力技术在建筑工程中推广的目的.     

无粘结部分预应力工艺在立交跨线桥上的应用

本文以深圳市机场立交为例，着重介绍无粘结部分预应力工艺在立交跨线桥上的应用。总结了无粘结部分预应力空心板的优点以及使用后的社会效益和经济效益。     

Densification and deformation during uniaxial cold compaction of stainless steel powder with different particle size

The behaviour of austenitic stainless steel powder column during uniaxial cold compaction was investigated in this work. Powders with different particle size were compacted to the same green density in a hydraulic press, also providing different H/D ratios in order to account for the influence of geometry. The analysis of the data continuously recorded by the press allowed distinguishing the contribution of the reversible phenomena (elastic deformation of powders and tools) and of the irreversible phenomena (rearrangement and plastic deformation of the powders). An analytical model for densification was proposed, considering both density and increase in density versus the applied pressure. The trend of reversible and permanent deformations versus the applied pressure was evaluated, also proposing an analytical model. The comparison between the densification curves and the curves of permanent deformation allowed highlighting the physical meaning of the model describing the increase in density for the different particle size.     

唐钢120t转炉污泥处理工艺

主要阐述了唐钢－炼钢厂易地在修工程转炉污泥的处理工艺以及污泥脱水机的形式。根据污泥特性,综合国内各种污泥脱水机的性能,着重阐述了带式压滤机的性能和工作原理。结合唐钢实际,分析和描述了系统采用斜板沉淀池和带式压滤机的合理性。     

锻造速度对粉末冶金烧结体塑性变形及性能的影响

研究了用液压机，曲柄压力机，空气锤及高速锤的打击速度对粉末冶金烧结体进行的镦粗试验，分析了变形程度，打击速度与锻件密度之间的关系。结果表明：烧结体的镦粗变形规律与致密体相同，指出了曲柄压力机是粉末锻造工艺的最佳设备。     

A Review of the Physical Metallurgy related to the Hot Press Forming of Advanced High Strength Steel

The automotive industry requirements for vehicle weight reduction, weight containment, improved part functionality and passenger safety have resulted in the increased use of steel grades with a fully martensitic microstructure. These steel grades are essential to improve the anti‐intrusion resistance of automotive body parts and the related passenger safety during car collisions. Standard advanced high strength steel (AHSS) grades are notoriously difficult to be press formed; they are characterized by elastic springback, poor stretch flangeability and low hole expansion ratios. Hot press forming has therefore received much attention recently as an alternative technology to produce AHSS automotive parts. In this contribution, the physical metallurgy principles of the hot press forming process are reviewed. The effect of composition on CCT curves of standard CMnB hot press forming steels is discussed taking the deformation during press forming into account. Furthermore,the effect of the static strain ageing processes occurring during the paint baking cycle on the in‐service mechanical properties of press hardened steel will be presented. The influence of temperate and strain rate on the flow stress during press forming and the final room temperature mechanical properties will be discuss ed. Moreover, the issues related to coatings on B‐alloyed CMn hot press forming steel will be critically reviewed. In particular the combined effects of thermal cycle and deformation on the degradation of the Al‐10%Si coating will be discussed in detail. Finally, the properties of both Al‐based and Zn‐based coating systems are compared, and the possibility of the formation of a diffusion barrier during press forming is discussed.     

60Si2Mn 钢高温变形抗力的热模拟实验测定

利用Ｇｌｅｅｂｌｅ－２０００热模拟试验机模拟测定了６０Ｓｉ２Ｍｎ、６０Ｓｉ、４０Ｃｒ及２０Ｍ等钢种的在高温下变地的真应力一真应变曲线,讨论了高温变形抗力与变形温度及形变量之间的关系,结果表明：高温变形抗力与变形温度及形变量有很大关系,变形抗力随主为形温度的升高而降低,同时认为６０Ｓｉ２Ｍｎ钢不会在马钢热轧生产中赞成对轧辊等设备及传动系统的损伤。     

炉壳液压顶升法在50t转炉检修中的应用

介绍了“炉壳液压顶升法”在太钢第二炼钢厂1~＃转炉大修中的运用。实践证明:该方法安全、可靠、先进、适用,达到了预期的目的。     

Deformation region in a stepwise-shaping press at OAO Chelyabinskii Truboprokatnyi Zavod

A method is developed for determining the ratio of the contact and noncontact zones in the deformation region on a stepwise-shaping press. Two histograms express the calculation results for biradial and triradial billet profiles in the deformation region with permissible reduction.     

冷轧带钢压下规程优化设计

通过实际算例，优化压下规程可使各道次的板型系数相等，表明板型达到最佳状态。该方法通过离散压下量，迭代计算得出板型良好的轧制压力所对应的变形量，对实际生产有指导作用。     

按照经济规律办事促进经济发展提高经济效益

为实现三年扭亏为盈的目标,鞍钢弓长岭矿业公司严格按经济规律办事,采取了如转变经营方式、精干主体、推进技术进步、向管理要效益一系列行之有效的措施,使企业摆脱了困境,重新焕发了生机。     

数控冲床送料机构交流伺服电机动力参数计算与选型

对数控冲床送料机构交流伺服电机相关动力参数作了系统的分析，推出了交流伺服电机各参数选取的计算式，并举例了东莞东华公司的LX328数控冲床的送料机构电机设计选型实例．