机械毕业设计外文翻译---装载机发展概况

机械毕业设计外文翻译---装载机发展概况
机械毕业设计外文翻译---装载机发展概况

外文资料翻译

学生姓名:

专业班级:机械设计制造及其自动化04级2班指导教师:

2008年6月

装载机发展概况

Abstract

This paper have discussed s.s. ZL-50 type fork-lift truck mainly overall fictitious prototype design as well as some kinds of typical schoolwork operating modes imitate and emulate , include equipment and the overall parts needed build mould. In this design course, have applied ADAMS software and the software of PRO/ENGINEER. ADAMS software is used in the emulation of some kinds of schoolwork operating modes, and the software of PRO/ENGINEER is used to build mould mainly. Through the simulated emulation for some kinds of overall schoolwork operating modes, can see relatively distinctly the overall possible condition in actual schoolwork course that met , can in time modify , have reduced actual design time , have raised production efficiency.

The innovation of this design Zhi is in in, imitate and have emulated fork-lift truck the 3 kinds of typical schoolwork operating mode in actual schoolwork, is effect again have imitated in actual schoolwork the hydraulic impact of use, so when being helpful to solve actual loading, the actual problem of meeting the stock that is hard to uninstall can so raise production efficiency.

Key words: Fork-lift truck 、fictitious prototype , build mould, emulation, optimization、production efficiency

Loader Development

China's modern 20 wheel loaders began in the mid-1960s of the Z435. The aircraft as a whole rack, rear axle steering. After years of hard work, the attraction was the world's most advanced technology wheel loader on the basis of the successful development of the power of 162 KW of shovel-fit wheel loaders, stereotypes for Z450 (later ZL50), and in 1971 December 18, formally appraised by experts. Thus the birth of China's first articulated wheel loader, thus creating our industry loader formation and development history.

Z450-type loader with hydraulic mechanical transmission, power shift, Shuangqiaoshan drive, hydraulic manipulation, articulated power steering, gas oil Afterburner brake wheel loaders, and other modern, the basic structure of the world's advanced level for the time . Basically represent the first generation of wheeled loading the basic structure. The aircraft in the overall performance of dynamic, and insertion force a rise of power and flexibility, manipulation of light, the higher operating efficiency of a series of advantages.

1978, Heavenly Creations by the Department in accordance with the requirements of machinery, worked out to LIUGONG Z450-based type of wheel loaders series of standards. The development of standards, with reservations Z

representatives loaders, L replaced by "4" on behalf of wheel, for ZL50 to Z450, it is so developed a LIUGONG ZL50-based China ZL-wheel loaders series of standards, this is Wong loader on the development of China's a major turning point. The standard was worked out by the industry after the division of labor, LIUGONG Xiamen ZL40 the manufacture of the large and medium wheel loaders, as workers, to the following small and medium-sized manufacturing ZL30 wheel loaders, and gradually formed a LIUGONG Xiamen workers, and 10% for workers at the loader to four backbone enterprises. To the late 1970s, early 1980s loader manufacturing enterprises in China has increased to more than 20, China has initially formed the loader industry. So far, China has developed wheel loader to the third generation, but the basic structure is still the Z450 (ZL50) evolved from. Change is not a very large second generation, third generation of some larger changes. 2001 China loader industry-wide total sales have exceeded 30,000 Taiwan, the world loader in the forefront of the market. Therefore, at present, China has become the world's loader marketing power.

Prospect of small loader

For a long time, small loader always been neglected in the status of a government department, not to regulate the management of the industry, well-known businesses loader products is dismissive. However, these did not affect small loader (hereinafter referred to small equipment) rapid development, and now with a small market despite its huge market demand has attracted such as the Long renowned engineering machinery enterprises to participate in the competition, the main battlefield in the rural areas with the small size of the market, sales have already reached 4 ~ 5 million, more than 200 brands to participate in market competition. But small market can be said to be installed speed expansion disorderly competition coexist. How to achieve industrial upgrading is placed in front of the small equipment industry must resolve a problem.

Lack industry attribution

Compared with large and medium-sized industries loaders, small with the development of the industry can use "plan" to describe, not only government departments related to the absence of industrial policies or development plans, and to date, industry has not completely clear attribution, the reality of the small equipment industries across engineering machinery, agricultural machinery and construction machinery, the three industries of grey areas. Despite the small market with a flourishing, but all small equipment manufacturers and dealers can dodge exists in the industry before the many obstacles to development.

Small installed mainly refers to the rated load between 0.3 ~ 0.9 T products, also known as micro-loader. As industry ownership is not clear, with small products has been no unified national technology and quality standards, the overwhelming majority of products are installed in the small-wheeled tractor developed on the basis of the. In addition small installed the product is currently used by the main component parts

from tractors and light truck, not by the needs of small equipment for low-speed heavy-duty bridge, special bins key component parts, including even small projects with special tires. As a low technical content, resulting in a very low threshold of industry and become the de facto "open" industry, any person, business can be very easily installed into small industries.

Small enterprises have installed a number of "fans", according to Construction Machinery Association Scraper Branch Secretary-General Chen Kai Yun, a conservative estimate at more than 200. More concentrated in Shandong Laizhou, Taian, Weifang, in Luoyang, Henan Province, Quanzhou, Fujian Province, and other places, annual sales of more than 2,000 Taiwan enterprises with a small handful, the majority of small businesses with annual sales in 3200 by the following, with the production of small enterprises , the same easy to set up and close down.

It is precisely because the strength of small enterprises with very limited products without high technology content, in the vast majority of enterprises to participate in market competition are in the process of basically a single means to price competition to sell products for the purpose, without taking into account future market things. In the common with the credit industry, services, brand competition means small industry basically not installed, in addition to differences in the strength of enterprises and product differentiation, marketing and management philosophy that is the

deep-seated causes.

Because users of the products of small equipment to mainly rural users, and users can only cover rural farm machinery sales networks, construction machinery and construction machinery sales are only part of the network coverage in rural areas. And the sale of equipment similar, with small products also requires agents or distributors can take the initiative to sell products to users and to users with standard and thoughtful service, and farm machinery dealers more customary sit shop operator, has no sales force, There is no specialized service teams, more difficult to expect the market planning, customer management. Construction machinery dealers and farm machinery dealers also have a lot of similarities, and engineering machinery dealers not accustomed to deal with rural users. Therefore, the small market is not mature with the sales network, to a large extent affected the market maturation process can not be achieved on the one hand, the user guide, on the other hand, can not be achieved on the manufacturers facilitating role. Operating environment and the use of the different habits, resulting in a lack of support for non-small pieces of installed products can hardly meet the actual needs of users, increasing the cost of services at the same time, improve customer satisfaction become almost impossible task.

Increased market differentiation

Unlike the preceding two years, with no small on the future of the market is basically no doubts. However, when the small rural installed by the new face of the

building the vast potential market demand, whether it is the product itself, or the level of industrial development is clearly not satisfied.

, And because of the double impact of external factors, with small market differentiation is an inexorable trend.

Relying solely on price competition means does not make the small favorably with industry development. In fact, it is due to excessive price competition, leading to small enterprises with low profitability, sales, and the prosperity of the entire industry can not hide the crisis of survival. Anticipate with a few small companies have started the "innovation" in the product upgrades at the same time, learn from the equipment industry and other related industries experience, to establish their own marketing team and distribution network and market competition tends to differentiation.

In the high-end users with the needs of small change, directly contributing to small enterprises with the differentiation, with the concept of progress and consumer financial strength of the expansion, some of the rural users (particularly in the industrialized operation of agriculture users) product performance and after-sales service and put forward higher requirements. Liaoning Anshan Haihong such as production of high-end products not only with small to have their own patented technology (use of mechanical devices greatly enhance the performance of its products, avoid using electric control, hydraulic devices, such as product performance after upgrading to the use of rural users increased maintenance costs ), and introduced the "non-controversial" services.

Especially in big enterprises with increased involvement of small enterprises with pressure, the end of 2006, the Dragon Holdings acquired Henan Baiyun electrical and mechanical equipment involved in the production of small fields.

Small with a huge potential market demand, but only to meet user needs, and guide the user needs, small equipment will have lasting vitality. Existing small enterprises with well-known loaders already facing small enterprises involved with the production sectors and small users to buy equipment or equipment, such as small excavators alternative products twin crises, with the production of small enterprises can take the initiative to upgrade their win more more time and greater market space.

Any industries are indispensable for the development of market competition and government regulations two factors. With the status quo on small industries, market competition and excessive government regulation missing, the entire industry in a very low level of operation development, and a lack of development of the industry often staying power will gradually shrink, or even disappear.

First to be addressed is the issue of trade with small, small equipment products really have their own products "definition", a special product standards. Although at this stage with small user groups mainly concentrated in the rural market, but the

market coverage of the future is certainly both urban and rural areas, this is because small equipment can be widely used for municipal maintenance, landscape construction, building and construction, underground loading and unloading areas.

Second, improve industry access threshold is a feasible solution. Small equipment industry can learn from the industry's largest equipment manufacturers licensing system, in terms of production quality suitable restrictions and improve the industry's manufacturing standards.

In recent years loader well-known enterprises in recent years have involved with the production of small areas, such as the Dragon, XCMG, and the mountains, but not really most of the production of one ton of small equipment products, the main reason is hindering their high-end products in the market inadequate capacity. However, this also means that for the small enterprises with not too much time, if not in the relatively short period of time upgrading of enterprises and products, from business philosophy, product marketing idea to the concept of all-round self-improvement,

self-transformed into a long-term development objectives and market

competition-conscious modern manufacturing enterprises, and a larger-scale sales, in the future and well-known enterprises loader win in the competition may be very small.

Mechanical Engineering Society of China was founded in 1936, China was set up earlier, the largest one of the Institute of Engineering. The existing 33 professional chapters, 180,000 members, of whom there are more than 3,000 senior members, more than 500 members of Hong Kong, Macao and overseas, there are more than 4,000 corporate members.

Academic exchange is the Institute's basic functions, the Institute is held annually hundreds, and colorful academic conferences. Special is an annual Chinese Mechanical Engineering Society annual meeting, the topic is the integration activities of the various large-scale comprehensive meeting. , The main thrust of the report will include the General Assembly, the topic of academic, scientific and technological progress releases, forums, lectures, display, a number of activities such as presentation, rich in content, as well as inside and outside the country in the industry has had a tremendous impact.

Editing, publishing and academic meetings and academic exchanges wings. Over the years, the organization has prepared a "China Materials Engineering ceremony," and "machine repair manual," such as hundreds of large-scale tool, science and technology books and related materials. Academic journals published by the "Journal of mechanical engineering", "Chinese Mechanical Engineering", more than 60 species, and for promoting the development of academic disciplines has played an important role.

Member Society is the mainstay of the Institute and the basis for the existence of the necessary conditions for achieving democracy Office will learn organizational guarantee. Member services is the Institute for the work of the main tasks of Institute staff is a sacred duty. Has been the establishment of a wide range of multi-level

structure and membership of the service system, and conducting appropriate Member activities, and actively explore characteristics of the times with the Member services. Institute of years of development experience has shown that membership is a source of vitality Institute.

Continuing education and professional certification is the Institute's an effective way to serve the community. Over the years, have carried out fruitful work. 1983 founded the mechanical engineer degree (now Beijing mechanical engineer OLI), is the first in China to establish a "mechatronics" and the "Industrial Engineering" two professional, and entrusted Quanguokaowei for higher education self-study examination. To welding and nondestructive testing for the representatives of accredited professionals work focused on quality, service-oriented economy, and widely alleged members and the industry peer Road. In recent years, actively promote the international mutual recognition of qualifications engineers.

Chinese Mechanical Engineering Society of China's machinery industry is a very important external communication channels, to the industry and the large number of government departments entrusted task of the international exchange and cooperation. Chinese Mechanical Engineering Society of China's accession to the representatives of 11 international organizations, 23 countries and 38 first-class academic institutions and professional organizations has signed bilateral cooperation agreements with more than 60 countries and regions, including more than 1,000 scientific research, teaching, design, manufacturing, consulting, intermediary and social welfare institutions established a good working relationship.

I will stick to science and technology and economic integration as the key link, and always bring the Institute for Scientific and Technological Advice as to promote economic development and work closely with the main battlefield, active structures for economic development platform. I will rely on his close "in Beijing Teng-day certification Advisory Center," galaxy of talent and give full play to the advantages of network, enterprises actively carry out technical advice, enterprise certification advisory and development strategy consulting. Not only to learn activities closer to the corporate and service industries, and effectively speed up the Institute's own capabilities and the enhancement of overall strength.

International Exhibition is I will carry out international exchanges and cooperation forms an important one. The exhibition platform, organizations Chinese and foreign entrepreneurs, technology sector between the exchanges and cooperation and promote economic and trade development and industrialization of technological progress. As Chinese Mechanical Engineering Society masterpiece in the field of exhibitions, Beijing Essen Welding and Cutting Fair has become first in Asia and second in the world in the welding professional exhibitions.

I will set up a "Chinese Mechanical Engineering Society Science and Technology Award", and China Machinery Industry Federation and jointly set up the "China Machinery Industry, Science and Technology Award." Over the years, the China Association for Science and Technology, Chinese Academy of Sciences, Chinese Academy of Engineering, recommending talents, and actively promote respect for independent innovation, and abide by scientific ethics, and the pursuit of harmony and

progress of scientific thought, effectively mobilize the broad masses of scientific and technological workers initiative and creativity.

I will also attach great importance to their work, procedures, scientific management and democratic management, and in 2004 took the lead in the national Institute adopted the ISO9001: 2000 quality management system certification. It is not only that I will work more scientific and standardized At the same time, the community has also been the recognition and praise.

翻译:

本文主要论述了ZL-50轮式装载机整机虚拟样机设计以及几种典型作业工况的模拟和仿真,包括工作装置和整机所需要部件的建模。该设计过程中,应用了ADAMS软件和PRO/ENGINEER软件。ADAMS软件用于几种作业工况的仿真,而PRO/ENGINEER软件主要用来建模。通过对整机几种作业工况的模拟仿真,可以较为清晰地看到整机在实际作业过程中可能遇到的状况,可以及时修改,减少了实际的设计时间,提高了生产效率。

本次设计的创新之处在于,模拟仿真了装载机在实际作业时的三种典型作业工况,再就是效仿了一下在实际作业时利用的液压冲击,这样有利于解决实际装载时遇到难以卸载的物料的实际问题,从而可以提高生产效率。

我国现代轮式装载机起始于20世纪60年代中期的Z435型。该机为整体机架、后桥转向。经过几年的努力,在吸收当时世界最先进的轮式装载机技术的基础上,开发成功了功率为162KW的铲接式轮式装载机,定型为Z450(即后来的ZL50),并于1971年12月18日正式通过专家鉴定。就这样诞生了我国第一台铰接式轮式装载机,从而开创了我国装载机行业形成与发展的历史。

Z450型装载机具有液力机械传动、动力换挡、双桥驱动、液压操纵、铰接式动力转向、气推油加力制动等现代轮式装载机的基本结构,为当时世界先进水平。也基本上代表了我国第一代轮式装载的基本结构。该机在总体性能方面具有动力性好,插入力有掘起力大、机动灵活、操纵轻便、作业效率高等一系列优点。

1978年,天工所根据机械部的要求,制订出以柳工Z450为基型的我国轮式装载机系列标准。制订标准时,保留用Z代表装载机,用L取代“4”代表轮式,改Z450为ZL50,就这样制订出了以柳工ZL50型为基型的我国ZL轮式装载机系列标准,这是我国装载机发展鸣上的重大转折点。该标准制订出来后按当时

的行业分工,柳工、厦工制造ZL40以上的大中型轮式装载机,成工、宜工制造ZL30以下的中小型轮式装载机,逐步形成了柳工、厦工、成工和宜工当时的装载机四大骨干企业。到70年代末、80年代初我国装载机制造企业已增加至20多家,初步形成了我国装载机行业。到目前为止,我国轮式装载机已经发展到了第三代,但最基本的结构仍然是由Z450(ZL50)演变而来。第二代变化不很大,第三代变化稍大一些。2001年我国装载机全行业总销售量已突破3万台,居世界装载机市场的前列。因此,目前我国已经成了世界上装载机产销大国。

小型装载机前景分析

长期以来,小型装载机始终处于被忽略的地位,政府部门没有对该行业进行规范管理,知名装载机企业对此产品也是不屑一顾。但是,这些并没有影响小型装载机(以下简称小装)的迅猛发展,而今的小装市场尽管以其巨大的市场需求吸引了诸如龙工这样的工程机械知名企业参与竞争,在以农村为主战场的小装市场规模已经发展到年产销4~5万台,有超过200个品牌参与市场竞争。但小装市场可以说是极速扩张无序竞争并存。如何实现产业升级是摆在小装行业面前的一道必须破解的难题。

缺失行业归属 ,与大中型装载机行业相比,小装行业的发展可以用“计划外”来形容,不仅政府部门没有制定相关的产业政策或发展规划,而且至今也没有彻底明确行业归属问题,现实中的小装行业是横跨工程机械、农业机械和建筑机械等三个行业的灰色地带。尽管,小装市场一片繁荣景象,但所有的小装生产企业和代理商都不能回避横亘在整个行业面前的诸多发展障碍。

小装主要指额定载荷在0.3~0.9T之间的产品,也称之为微型装载机。由于行业归属不明确,小装产品至今没有统一的国家技术质量标准,绝大多数小装产品都是在四轮拖拉机的基础上开发出来的。此外小装产品目前所使用的配套件主要来源于拖拉机和轻卡,没有小装所需要的低速重负荷专用桥、专用箱等关键配套件,甚至包括小装专用的工程轮胎。由于技术含量很低,导致行业门槛非常低,成为事实上的“不设防”的行业,任何人、企业都可以十分轻易地进入小装行业。

至今小装生产企业的数量是一个“迷”,据工程机械协会铲运分会秘书长陈凯运先生保守估计在200家以上。比较集中在山东莱州、泰安、潍坊、河南洛阳、

福建泉州等地,年产销量超过2000台的小装企业屈指可数,多数小装企业的年产销量在200台以下,因此对于小装生产企业而言,成立与倒闭同样容易。

正是由于小装企业的实力十分有限,产品技术含量又不高,导致绝大多数企业在参与市场竞争的过程中基本上都是采取价格竞争单一手段,以售出产品为目的,而不考虑未来市场的事情。在大装行业常见的信用、服务、品牌等竞争手段,小装行业基本上都没有,除了企业实力差异和产品差异之外,营销理念和管理水平恐怕是深层次的原因。

因为小装产品的用户以农村用户为主,而能够覆盖农村用户的只有农机销售网络,建筑机械和工程机械销售网络都只能部分覆盖农村。和大装销售方式相似,小装产品也要求代理商或经销商能够主动向用户销售产品和向用户提供规范周到的售后服务,而农机经销商多习惯坐店经营,没有专门的销售队伍,也没有专门的服务队伍,更难奢望市场策划、客户管理等。建筑机械经销商与农机经销商也有很多的相似性,而工程机械经销商又不习惯与农村用户打交道。因此,小装市场没有成熟的销售网络,在很大程度上影响了市场成熟进程,一方面不能实现对用户的引导作用,另一方面又不能实现对厂家的促进作用。作业环境和使用习惯的不同,导致缺乏非专用配套件的小装产品根本难以满足用户的实际工作需要,增加服务成本的同时,提高用户满意度几乎成为不可能完成的任务。

市场分化加剧,与前两年不同是,关于小装有没有市场前途的疑虑基本上没有了。但是,当小装面对由新农村建设带来的庞大潜在市场需求时,无论是产品本身,还是产业发展水平,显然都不能满足。

在内因和外因的双重影响下,小装市场出现分化是一种必然趋势。

单纯依靠价格竞争手段,并不能使小装行业得到良性发展。事实上,正是由于过度价格竞争,导致小装企业普遍盈利能力低下,销量上的繁荣并不能掩盖整个行业的生存危机。少数先知先觉的小装企业已经开始启动了“革新计划”,在对产品进行升级换代的同时,借鉴大装行业及其他相关行业的经验,建立自己的营销队伍和分销网络,市场竞争趋于差异化。

中高端小装用户的需求变化,直接带动了小装企业的分化,随着消费观念的进步和资金实力的壮大,部分农村用户(尤其是从事农业产业化经营的用户)对产品性能和售后服务等提出了更高的要求。如辽宁鞍山海虹生产的高档小装产

品不仅拥有自己的专利技术(利用机械装置大幅度提升产品性能,避免利用电控、液压等装置升级产品性能后给农村用户带来的使用维护成本上升),而且推出了“无争议”服务。

特别是大装企业介入加大了小装企业压力,2006年底,龙工控股收购了河南白云机电,涉入小装生产领域。

小装有巨大的潜在市场需求,但只有做到满足用户需求和引导用户需求,小装才会有持久的生命力。现有小装企业已经面临装载机知名企业介入小装生产领域和部分小装用户转向购买大装或小型挖掘机等其他替代产品的双重危机,因此小装生产企业主动升级才能够为自己赢得更多的时间和更大的市场空间。

任何一个产业的发展都离不开市场竞争和政府规范两方面的因素。就小装行业现状而言,市场竞争过度而政府规范缺失,使得整个产业在一个很低的层次上运行发展,而一个缺乏发展后劲的产业往往会逐渐萎缩,甚至消失。

首先要解决的是小装行业归属问题,使小装产品真正拥有属于自己的产品“定义”,有专门的产品衡量标准。尽管现阶段小装用户群体主要集中在农村市场,但未来市场覆盖面肯定是城市与农村兼有,这是因为小装可以广泛用于市政维护、园林建设、建筑施工、井下装卸等领域。

其次,提高行业准入门槛不失为一个可行的办法。小装行业可以借鉴大装行业推行的制造许可证制度,在企业生产资质方面给予适当的限制,提高整个产业的制造水平。

近年来装载机知名企业近年来纷纷涉入小装生产领域,如龙工、徐工、山工等,但大多并未真正生产1吨以下小装产品,阻碍他们的主要原因是中高档产品市场容量不足。但是,这也意味留给小装企业的时间并不太多,如果不能在较短时间内实现企业和产品升级,从经营理念、产品理念到营销理念全方位自我革新,把自身改造成为一个具有长远发展目标和现代市场竞争意识的制造企业,并获得较大的销量规模,那么在未来与装载机知名企业的竞争中胜出的可能就很小。

中国机械工程学会成立于1936 年,是我国成立较早、规模最大的工科学会之一。现有33 个专业分会,18 万名会员,其中有3 000 余名高级会员,500 余名海外和港澳台会员,还有4 000 余个团体会员。

学术交流是学会的基本职能,学会每年举办数以百计、丰富多彩的学术会议。特别是每年一度的中国机械工程学会年会,是集成各类专题活动的大型综合性会议。年会包括主旨报告大会、专题学术会议、科技进展发布、论坛、讲座、展示、颁奖等多项活动,内容丰富,在行业内外乃至全国都产生了巨大影响。

编辑出版与学术会议是学术交流的两翼。多年来,组织编写了《中国材料工程大典》、《机修手册》等数百种大型工具书、科技图书和相关教材。出版的学术刊物有《机械工程学报》、《中国机械工程》等60 余种,对推动学科发展起到了重要作用。

会员是学会的主体,是学会存在的基础和必要条件,是实现学会民主办会的组织保证。为会员服务是学会工作的主要任务,也是学会工作人员的神圣职责。至今已建立了多元化的会员结构与多层次的服务体系,有针对性地开展会员活动,积极开拓具有时代特征的会员服务。学会多年来的发展经验表明,会员是学会活力的源泉。

继续教育和专业人员资格认证是学会服务社会的有效形式。多年来,开展了卓有成效的工作。1983 年创办了机械工程师进修大学(现北京机械工程师进修学院),在国内率先设立了“机电一体化”和“工业工程”两个专业,并委托全国考委进行高等教育自学考试。以无损检测和焊接为代表的专业人员资格认证工作讲求质量,服务经济,广为会员和业内同行所称道。近年来,又积极推进工程师资格的国际互认。

中国机械工程学会是我国机械行业非常重要的对外交流渠道,承担了行业和政府部门委托的大量国际交流合作任务。中国机械工程学会代表中国加入了11 个国际组织,与23 个国家的38 个一流学术团体和专业组织签订了双边合作协议,并与60 余个国家和地区的千余个科研、教学、设计、制造、咨询、中介以及社会公益机构建立了良好的工作关系。

我会坚持科技与经济结合为纲,始终把开展科技咨询作为促进学会工作与经济建设紧密结合的主战场,积极搭建为经济建设服务的平台。紧密依靠我会所属的“北京中机天腾认证咨询中心”,充分发挥人才荟萃和组织网络的优势,积极开展企业技术咨询、企业认证咨询和发展战略咨询。不仅使学会活动更加贴近企业,服务行业,而且有效地加快了学会自身能力和整体实力的提高。

国际展览会是我会开展国际交流与合作的重要形式之一。通过展览平台,组织中外企业界、技术界之间的交流与合作,促进了经贸发展和产业技术进步。作为中国机械工程学会在展览领域的杰作,北京· 埃森焊接与切割展览会已成为亚洲第一、世界第二的焊专业展览会。

我会设立了“中国机械工程学会科技奖”,并与中国机械工业联合会共同设立了“中国机械工业科学技术奖”。多年来,向中国科协、中国科学院、中国工程院举荐优秀人才,积极弘扬崇尚自主创新、恪守科学道德、追求和谐进步的科学思想,有效地调动了广大科技工作者的积极性和创造性。

我会还十分重视工作制度、工作程序、科学管理和民主办会,并于2004 年率先在全国性学会中通过了ISO9001:2000 质量管理体系认证。它不仅使我会工作更加科学化和规范化,同时,也得到了社会各界的认可与好评。

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毕业设计外文翻译

毕业设计(论文) 外文翻译 题目西安市水源工程中的 水电站设计 专业水利水电工程 班级 学生 指导教师 2016年

研究钢弧形闸门的动态稳定性 牛志国 河海大学水利水电工程学院,中国南京,邮编210098 nzg_197901@https://www.360docs.net/doc/2b15473804.html,,niuzhiguo@https://www.360docs.net/doc/2b15473804.html, 李同春 河海大学水利水电工程学院,中国南京,邮编210098 ltchhu@https://www.360docs.net/doc/2b15473804.html, 摘要 由于钢弧形闸门的结构特征和弹力,调查对参数共振的弧形闸门的臂一直是研究领域的热点话题弧形弧形闸门的动力稳定性。在这个论文中,简化空间框架作为分析模型,根据弹性体薄壁结构的扰动方程和梁单元模型和薄壁结构的梁单元模型,动态不稳定区域的弧形闸门可以通过有限元的方法,应用有限元的方法计算动态不稳定性的主要区域的弧形弧形闸门工作。此外,结合物理和数值模型,对识别新方法的参数共振钢弧形闸门提出了调查,本文不仅是重要的改进弧形闸门的参数振动的计算方法,但也为进一步研究弧形弧形闸门结构的动态稳定性打下了坚实的基础。 简介 低举升力,没有门槽,好流型,和操作方便等优点,使钢弧形闸门已经广泛应用于水工建筑物。弧形闸门的结构特点是液压完全作用于弧形闸门,通过门叶和主大梁,所以弧形闸门臂是主要的组件确保弧形闸门安全操作。如果周期性轴向载荷作用于手臂,手臂的不稳定是在一定条件下可能发生。调查指出:在弧形闸门的20次事故中,除了极特殊的破坏情况下,弧形闸门的破坏的原因是弧形闸门臂的不稳定;此外,明显的动态作用下发生破坏。例如:张山闸,位于中国的江苏省,包括36个弧形闸门。当一个弧形闸门打开放水时,门被破坏了,而其他弧形闸门则关闭,受到静态静水压力仍然是一样的,很明显,一个动态的加载是造成的弧形闸门破坏一个主要因素。因此弧形闸门臂的动态不稳定是造成弧形闸门(特别是低水头的弧形闸门)破坏的主要原是毫无疑问。

本科毕业设计外文翻译

Section 3 Design philosophy, design method and earth pressures 3.1 Design philosophy 3.1.1 General The design of earth retaining structures requires consideration of the interaction between the ground and the structure. It requires the performance of two sets of calculations: 1)a set of equilibrium calculations to determine the overall proportions and the geometry of the structure necessary to achieve equilibrium under the relevant earth pressures and forces; 2)structural design calculations to determine the size and properties of thestructural sections necessary to resist the bending moments and shear forces determined from the equilibrium calculations. Both sets of calculations are carried out for specific design situations (see 3.2.2) in accordance with the principles of limit state design. The selected design situations should be sufficiently Severe and varied so as to encompass all reasonable conditions which can be foreseen during the period of construction and the life of the retaining wall. 3.1.2 Limit state design This code of practice adopts the philosophy of limit state design. This philosophy does not impose upon the designer any special requirements as to the manner in which the safety and stability of the retaining wall may be achieved, whether by overall factors of safety, or partial factors of safety, or by other measures. Limit states (see 1.3.13) are classified into: a) ultimate limit states (see 3.1.3); b) serviceability limit states (see 3.1.4). Typical ultimate limit states are depicted in figure 3. Rupture states which are reached before collapse occurs are, for simplicity, also classified and

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