摘   要随着经济的快速发展，人们对粮食、煤炭、矿石、等资源型干散货需求不断增加。此外又由于资源的分布不均匀，船舶运输为主的干散货国际贸易量日益增长，干散货运输朝着港口装卸专业化、船舶大型化的方向发展。在码头和港口的货物流程中，都必需由码头和港口前沿的机械设备从船舱内将货物取出来。桥式抓斗卸船机是目前世界上用于港口散货船接卸的主要机械设备。桥式抓斗卸船机具有安全可靠、运营成本低、适应性好等优点。桥式抓斗卸船作为码头和港口散货装卸的主要设备之一，卸船机的性能对散货卸船效率以及散货船停泊时间起着至关重要的影响。

金属结构在桥式抓斗卸船机中是支撑整个机械的重要组成部分。在本文中介绍了卸船机整机的结构特点。我们通过对整机结构进行分析，发现卸船机各主要结构件都是由箱型截面梁组成，故在后续的工作中我们选择前大梁，一个具有代表性同样也是最复杂的结构进行有限元分析。86047

本文以800t/h桥式抓斗卸船机前大梁为原型。利用ANSYS有限元软件建立桥式抓斗卸船机前大梁模型。根据卸船机工作时的不同种工况，分析了卸船机前大梁承受的不同种载荷。通过有限元分析软件对前大梁进行了较为系统的静力学和动力学仿真分析，完成了其强度计算并得到了其在不同种工况下的应力云图和位移图。根据应力云图和位移图可以得到在不同工况条件下前大梁的最大应力值和最大应力值位置，从而得出桥式抓斗卸船机的安全性能好坏以及为平时检修和检测找出需要重点关注的危险部位，给桥式抓斗卸船机的设计、使用、安全评估和定期检验提供一定的理论基础，此外可为散货码头和港口设计重要设备的性能提供参考。

关键词：桥式抓斗卸船机；前大梁；有限元分析；应力云图；位移图

Abstract

With the rapid development of economy, people's demand for grain, coal, ore, and other resource type dry bulk cargo is increasing。 In addition, due to the uneven distribution of resources, the international trade volume of dry bulk cargo is increasing day by day, and the dry bulk cargo transportation is developing towards the direction of specialization and large scale。 In the process of cargo flow in the wharf and the port, the machinery and equipment in the front of the wharf and the port must be removed from the ship's cabin。 Bridge type grab ship unloader is currently the world's major mechanical equipment for bulk cargo ports。 Ship unloader has the advantages of safe and reliable operation, low cost, good adaptability etc。 Bridge type grab ship unloader as one of the main equipment of the wharf and port bulk cargo loading and unloading, relief ship machine's performance on the bulk cargo unloading ship efficiency and bulk cargo ship berthing time plays a crucial impact。

The metal structure in the grab bridge ship unloading machine is an important part of the whole mechanical support。 In this paper, the structural characteristics of the ship unloading machine are introduced。 We through the analysis of the whole structure, found that the unloading machine for ship structures are composed of box section beam, so in subsequent work we choose the front beam, a representative is also the most complex structure of finite element analysis。

In this paper, 800t/h bridge type grab ship unloader front beam as the prototype。 Using ANSYS finite element software to establish ship unloader front beam model。 According to the different working conditions of the ship unloader work, analyzes the different kinds of ship unloader front beam under load。 Through the finite element analysis software for the statics and dynamics simulation analysis to systematically front beam, the strength calculation is completed and the stress nephogram and displacement graph under different working conditions are obtained。 The stress nephogram and displacement graph can be obtained in under the different conditions of the front beam of maximum stress value and the maximum stress value position, so as to get the bridge type grab unloading ship machine safety performance is good or bad and for routine maintenance and testing to identify the need to focus on the dangerous parts, to provide a theoretical basis for the design, use, safety assessment and regular inspection of bridge type grab ship unloader, in addition, it can provide a reference for the performance of the important equipment in the design of bulk cargo terminals and ports。