夹钳起重机的夹钳装置

夹钳装置是夹钳起重机的取物装置,夹钳起重机能否可靠地工作,主要取决于夹钳的性能。本文介绍几种常用夹钳装置的结构形式、工作原理及优缺点对比。供设计与使用夹钳起重机时参考。     

起重机自动梯形板坯夹钳

主要介绍了一种自动梯形板坯夹钳的构造、原理及性能特点。     

定柱旋臂式起重机的受力计算

目前，国外公司的旋臂式起重机越来越多地引起关注。定柱旋臂式起重机是一种室内使用的轻小起重设备，由于其占地面积少，安装使用方便，而且使工位使用者不必等待大型桥式起重机进行物料的搬运与移动，能提高工作效率。本文对定柱旋臂式起重机的受力进行一种简便的力学模型分析与计算，供设计者参考。     

起重机轨道压板受力计算

分析了起重机轨道的受力,推导出了起重机轨道压板所受的外力,再由有限元素法求出了压板各部位的应力分布,以此来判断压板的安全性。     

起重机夹钳吊具概述

根据扳坯连续和轨道工艺及冷轧技术的需要,设计了各种钢坯、纲卷的专用夹钳吊具。通过冶金企业生产实践,其吊具运用平稳、工作可靠,并对各种吊具列出优缺点可供用户选用时参考。     

25—112t电动平移式板坯夹钳起重机

电动平移式板坯夹钳起重机是一种新型的板坯夹钳起重机 ,它具有操作简单 ,安全可靠 ,生产效率高等特点。它是连铸和热连轧生产线上必不可少的起重搬运设备 ,已在武钢、鞍钢、宝钢和本钢使用 ,效果良好。1　主要技术参数2 5～ 112ｔ电动平移式板坯夹钳起重机系列的起升、运行速度均为可调速度 ;对于跨度较小者 ,其运行速度较低 ;对于板坯长度较大者可采用 4对夹钳 ;检测吊钩也可设在吊具横梁 2侧。该系列起重机的主要参数如下 :起重量 :2 5～ 112ｔ (夹钳 ) ;2 5～ 63ｔ (吊钩 )跨　度 :13 5～ 39 5ｍ起升高度 :7～ 10ｍ起升速度 :10 / 1ｍ/…     

45／50t钢锭夹钳起重机简介

对45/50t钢锭夹钳起重机的构造、原理及性能特点进行了简要介绍，重点叙述了夹钳开闭机构、夹钳旋转机构。     

起重机卷筒受力模型探讨

对起重机起开卷筒受力模型进行详细分析,为危险部位应力计算和正确选择卷筒体厚度作了准备工作．     

起重机在铁路运输中的受力分析

１引言起重机产品在铁路运输过程中,由于受到各种外力的作用将会发生位移,致使起重机因窜动、滚动、倾覆、倒塌或坠落等情况而遭到破坏,甚至发生重车（装载有货物的列车）颠覆的严重事故。因此,有必要对起重机在铁路运输中所受的外力进行分析,并由此计算出外力的大小...     

基于ADAMS的汽车起重机动态受力计算

通过分析汽车起重机发生倾覆应满足的条件,运用大型力学分析软件ADAMS,建立简化模型,进行动态受力计算,为重型汽车起重机在工作中运动参数的设定提供参考.     

塔机基础计算方法

GB/T 13752—92《塔式起重机设计规范》中给出了方形基础抗倾翻稳定性和地耐力的计算公式,但它并不适用于其他形式的基础(比如十字形基础),也不能满足方形基础所有工况的要求.通过对方形基础进行力学分析,根据塔机基础载荷,推导出适用于各种形式基础的抗倾翻稳定性、地耐力通用计算方法.此方法可以计算出基础上任何1个截面的弯矩、剪力,为配筋的设计提供了依据.     

港口起重机自锁夹轨器可靠性分析

给出了港口起重机防风自锁夹轨器的工作原理及与自锁相关参数的关系，结合自锁夹轨器具体使用环境条件和技术条件，分析设计和使用中的问题，得出相应结论，提出了提高使用自锁夹轨器工作可靠性的建议，指导自锁夹轨器选型设计和使用维护。     

Analytical model for estimating intersegmental forces exerted on human lower limbs during walking motion

Existing methods for evaluating the intersegmental forces acting on the human lower limbs during walking generally measure the ground reaction force exerted on the feet using force plates and estimate the intersegmental forces using an inverse dynamics approach. However, force plates are inconvenient and expensive. Accordingly, the present study proposes an approach for evaluating the intersegmental forces without the need for force plates by modeling the human lower limbs as a seven-link manipulator system. In the proposed approach, the intersegmental forces are derived directly from the analytical model using Newton–Euler theory based on the posture information obtained from a system of gyroscopes and accelerometers during walking motion. The results obtained from the analytical model are compared with the experimental data obtained using load cells. It is found that the estimated results are in good agreement with the measured results. Thus, the basic validity of the proposed analysis system is confirmed.     

斗轮着地状态载荷计算

斗轮堆取料机整机平衡方式多种多样，活配重平衡方式是应用较多的1种，其典型结构见图1。其中门柱是连接前臂架、配重架的重要结构件，它通过前拉杆、水平拉杆、斜支架连接前臂架，前臂架上装有斗轮机构和悬臂带式输送机等部件，通过后拉杆连接配重架，配重架上装有配重块。以门柱     

某型起重机械低阶模态实测的传感器优化配置

为了在某型起重机械的低阶模态实测实验中获得较高质量的动力学信息,从参数识别的不确定性和多阶模态的振型匹配两个角度,以信息熵和振型相关系数矩阵的最大非对角元两个优化准则给出优化目标函数,采用逐步累积算法,对现场实验传感器配置进行优化.另外在低阶模态振型矩阵中加入高阶模态,验证优化算法的有效性.     

Pressure sensor matrix for indirect measurement of grip and push forces exerted on a handle

To date, a large part of workers is exposed to vibrations (23% in Europe) which can negatively impact on their health. This work discusses the importance of measuring grip and push forces in the context of hand-arm vibration tests, bearing in mind the state-of-art of current standards. It proposes a method for indirect measurement of coupling forces using a matrix of polymeric pressure capacitive sensors and discusses the model used for defining these quantities. The matrix of pressure sensors is wrapped around the tool handle and the acting forces, exchanged with the handle, are derived from the pressure values measured by the matrix. Calibration is presented and the effect of curvature is discussed. The work continues with the experimental validation of the model proposed for push force measurements carried out through lifting tests using known masses with a cylindrical handle. An experimental correction coefficient is defined in correlation to the type of grip. The method for measuring the push force, thus corrected, is assessed by means of push force tests on an instrumented handle. Finally the experimental data are analysed in order to assess the uncertainty of the proposed method for measuring the push force, highlighting the contribution of the different sources of uncertainty. The proposed measurement method allows to measure the push and the grip force (known influencing quantities for the measurement of the hand-arm vibration) during tool test and without modifying the handles.     

A photoelastic substrate technique for dynamic measurements of forces exerted by moving organisms

The forces produced by small moving organisms have been quantitatively measured by having the organisms move on a polymeric substrate which transduces the applied stress into an optical birefringence signal (photoelastic effect). The optical signal can be rigorously interpreted to give static force measurements, and by calibrating the substrate empirically, dynamic measurements are obtained. The technique measures stresses, forces applied to an area, so it is not possible to determine ultimate sensitivity of the technique for measurements of forces without regard to area. The technique is especially useful when small forces are exerted over very small areas as, for example, may be the situation with moving tissue cells. The technique is noninvasive, requires minimal equipment, and is easily performed on microscopes adapted for polarized light measurements. Gelatin has the highest sensitivity and adaptability as a photoelastic substrate.     

起重机卷筒钢丝绳双层缠绕起升高度的计算

随着我国工业建设的发展,在电力、自来水、冶金行业等领域,对大起升高度起重机的需求量越来越多,为了满足用户的要求,节约成本,尽量利用现行起升机构的通用部件,采用卷筒钢丝绳双层自由缠绕实现大起升高度。对工作级别不大于A5的起重机而言,较为经济。为了保证起重机结构质量,而且将来形成一定的系列,方便其推广工作,本文以起重量50t起升机构为例,对双层自由缠绕的设计计算进行分析。     

塔式起重机动力系数的计算与分析

应用有限元法,以ＴＱ１－６塔式起重机为例,通过结构分析计算,掌握了塔机的动态特性,为塔机动力系数的简化计算提供了理论依据,并导出了简化计算公式。     

起重机大车行走机构制动器制动距离的计算

介绍了集装箱起重机大车行走机构制动器的工况,对大车行走机构制动器在急停情况下的工况进行了详细分析和计算,并以一集装箱起重机的大车行走机构制动器计算为例,详细论述了制动器切入后,急停电机至制动器有效作用期间,制动器滞后时间0.3 s内,大车以原速度在风力作用下加速行走的距离S1和制动器滞后制动时间过后,制动器进行制动,起重机制动的有效距离S2的计算方法,得出了起重机大车行走机构制动器在急停情况下移动的总行程。为此类制动器装置的设计和计算提供了依据。