畢業(yè)論文MN板框式模鍛液壓機本體設(shè)計

1、本科畢業(yè)設(shè)計（論文） 8MN板框式模鍛液壓機本體設(shè)計學院（系）： 機械工程學院 年級專業(yè)： 2010級 學生姓名： 指導教師： 答辯日期： 2014年 月 日 摘 要大型模鍛件制造水平的高低與航空航天、核電、船舶、軍工等行業(yè)的發(fā)展存在著直接的聯(lián)系并產(chǎn)生深遠的影響。為了滿足對大型鍛件日益增長的需求，用于其生產(chǎn)的主要設(shè)備大型模鍛液壓機的研究、開發(fā)就顯得更加迫切。模鍛液壓機本體結(jié)構(gòu)多種多樣，其中，板框組合式結(jié)構(gòu)可以很好的解決大型壓機高承載引起的一系列問題，所以國內(nèi)外大型模鍛液壓機廣泛采用此結(jié)構(gòu)。目前大型板框式模鍛液壓機板框結(jié)構(gòu)形式主要有三類：框架由多層橫板和豎板聯(lián)成框架由多層整片“O”形鋼板相互疊加

2、通過預緊而成框架由多層帶鉤頭的鋼板組合成。液壓機框架由多層帶“C”形鉤頭鋼板組合成可以節(jié)省材料，降低成本，而且還能夠解決加工、制造、安裝、運輸?shù)葐栴}，減少應(yīng)力集中現(xiàn)象出現(xiàn)，提高了機架的強度，明顯優(yōu)于其它結(jié)構(gòu)。在設(shè)計過程中，根據(jù)液壓機的主要技術(shù)參數(shù)算出主工作缸、穿孔缸、回程缸、平衡缸、上梁板、下橫梁、活動橫梁、“C”形板、大拉桿、上下夾緊梁和上十字鍵等的主要尺寸。液壓缸作為液壓機的關(guān)鍵部件，必須擁有足夠的強度或剛度，所以必須通過校核計算，確定液壓缸最終尺寸，并且利用UG軟件，建立了橫梁、夾緊梁，上十字鍵和整體框架等零部件的實體模型，以Marc有限元軟件作為分析工具，對主要受力零部件進行了三維有限

3、元計算，對其結(jié)構(gòu)的合理性和應(yīng)力集中情況進行了分析，最終完成設(shè)計。關(guān)鍵詞：模鍛，液壓機，本體，板框式，建模，有限元，分析AbstractThe level of large forging manufacturing there is a direct link with aerospace, nuclear power, shipbuilding, war industry and other industries development and have a profound impact. In order to meet the increasing demand for large f

4、orgings, used for the production of large forging hydraulic press which is the main equipment research, development, becomes more urgent. Die forging hydraulic press frame structure is varied, among them, plate and frame composite structure can solve a series of problems caused by the large press hi

5、gh bearing well, so the domestic and foreign large forging hydraulic press widespread adoption of the structure. So far, the plate and frame structure of a large plate and frame type die forging hydraulic press mainly has three categories: (1) framework by multi-layer rung and got behind vertical pl

6、ate (2) framework by multilayer entire "O" shape steel overlay each other by preloaded into (3) framework by multilayer belt hook plate combined into. Hydraulic press frame by "C" shaped hook and multi-layer steel plate combination can save materials, reduce cost, but also can so

7、lve the problem of processing, manufacture, installation, transportation and so on, to reduce stress concentration phenomenon, improve the strength of the chassis, is superior to other structures.In the design process, according to the main technical parameters to calculate the primary work cylinder

8、 of hydraulic press, punch, the return cylinder and balance cylinder, the beams, activity "C" shape plate, bar, upper and lower clamping beam and the main dimensions of the cross key, etc. Hydraulic cylinder as the key components of hydraulic press, must have sufficient strength and rigidi

9、ty, so must pass the check calculation, determine the hydraulic cylinder size, and by using UG software, set up the beam, the clamping beam, cross key parts such as entity model and the overall framework, with finite element software Marc as analysis tool, the main stress components of the three-dim

10、ensional finite element calculation, the structure of rationality and stress concentration was analyzed, and the final design.Keywords: die forging hydraulic press, ontology, plate and frame type, modeling, finite element，analysis第1章 緒論1.1 課題背景為了滿足電力、船舶、航空、航天和國防工業(yè)對大型鍛件日益增長的需求，大型模鍛液壓機的開發(fā)、研究是不可避免的而且十分

11、迫切的。早在上世紀中葉，法國、前蘇聯(lián)和美國等先進制造國家就投建并應(yīng)用于生產(chǎn)中一大批4萬噸級以上的大型模鍛液壓機，極大程度的帶動了本國的航空、汽車等制造業(yè)，當時生產(chǎn)的大批優(yōu)質(zhì)鍛件至今仍在使用而且性能良好。到上世紀末前蘇聯(lián)和美國設(shè)計制造的壓力機比例達到世界總量的七成左右，前蘇聯(lián)發(fā)展液壓機技術(shù)較早，于1959年設(shè)計制造的兩臺7.5萬噸大型模鍛液壓機一直沿用至今。我國模鍛液壓機研究起步較早，后來由于各種原因研究工作擱置下來。我國8萬噸模鍛液壓機順利投產(chǎn)標志著我國已經(jīng)步入鍛造大國行列。 通過8MN板框式模鍛液壓機的設(shè)計、研究可以初步的掌握模鍛液壓機的結(jié)構(gòu)和工作原理，解決出現(xiàn)的問題進一步優(yōu)化設(shè)計過程，為以

12、后大型、巨型模鍛液壓機的設(shè)計制造做好技術(shù)儲備。此外，通過完成此設(shè)計過程來鞏固學過的知識，提高自己的能力。 綜述本課題國內(nèi)外研究動態(tài)模鍛液壓機主要應(yīng)用領(lǐng)域為電力、船舶、航空航天行業(yè),大型模鍛液壓機是我國大型鍛件在模鍛過程中的重要設(shè)備,過去我們國家沒有大型壓力機，致使一些鍛件不得不依靠進口，這始終束縛著我國航空、航天、汽車、兵器等行業(yè)的發(fā)展?，F(xiàn)階段而言，我國8萬噸模鍛液壓機順利投產(chǎn)使我國成為世界擁有數(shù)量最多、噸位最大重型模鍛鍛壓設(shè)備的國家，但是從設(shè)備構(gòu)成、等級、技術(shù)水平和所生產(chǎn)的鍛壓件的品種、精度、工藝水平方面與國外比，我們還有一些差距。早在上世紀八十年代林秀安，聶紹珉對鋼板組合機架做過研究；聶紹

13、珉、金淼和吳生富等對全預緊機架整體性能進行了分析；我校黃學玲也通過工程算法對650MN液壓機預緊機架進行受力分析并制作一臺1:10樣機安裝在實驗室；現(xiàn)階段，國內(nèi)對800MN模鍛液壓機的研究最多，早在2005年，我們學校的田會然、張慶等就對其本體結(jié)構(gòu)進行了設(shè)計與分析；2010年，楊固川、于江等人對大型模鍛液壓機機架結(jié)構(gòu)進行了分析研究；中國第二重型機械集團公司通過對設(shè)計、研究以及國內(nèi)外已建成液壓機性能分析比較得出：采用C形板機架結(jié)構(gòu)建造出800MN模鍛液壓機；而國外，早在1959年前蘇聯(lián)建造的750MN模鍛液壓機即為板框組合式結(jié)構(gòu)；美國建造的450MN模鍛液壓機采用立柱以“T”形鉤頭板作為主要受力

14、構(gòu)件的結(jié)構(gòu)；法國的650MN多向模鍛液壓機則以“C”形鉤頭板為主要受力構(gòu)件。目前已投產(chǎn)的大型板框式模鍛液壓機板框結(jié)構(gòu)形式簡介.1液壓機框架由多層橫板和豎板聯(lián)成前蘇聯(lián)建造的750MN模鍛液壓機就是這類結(jié)構(gòu)（見圖1），它是用多層的橫板和豎板通過螺栓、鍵和銷聯(lián)接成整體的框架來承受液壓機的公稱壓力。這種結(jié)構(gòu)形式能夠使得大型、巨型液壓機的加工、輸送和組裝方便簡單容易實現(xiàn)，然而由于它由多層橫板和豎板構(gòu)成整體，聯(lián)接部位繁多，構(gòu)成復雜，聯(lián)接形式不單一，而且聯(lián)接部位應(yīng)力集中現(xiàn)象十分顯著，大大的降低了機器框架的強度和承載壓力的能力，也在一定程度上浪費了制造機架的材料增加了成本。.2液壓機框架由多層整片“O”形鋼板

15、相互疊加通過預緊而成 由多層整片的“O”形鋼板疊加構(gòu)成基本框架，以螺栓緊固聯(lián)接構(gòu)成一個整體。這種形式的機架具有整體性好，受力狀態(tài)好，容易設(shè)計，通用性強，結(jié)構(gòu)簡單等一系列優(yōu)點，但是大型、巨型壓力機不太適用，因為大型的“O”形鋼板的制造、運輸和安裝目前都存在許多問題難以解決。圖1前蘇聯(lián)的750MN模鍛液壓機實物圖.3液壓機框架由多層帶鉤頭的鋼板組合成該形式的機架常常被稱作“C”形或者“T”形機架，由多層帶有特定鉤頭的厚鋼板組合形成，結(jié)構(gòu)緊湊、簡單。比如美國4.5萬噸模鍛液壓機的立柱是用帶有“T”形鉤頭的鋼板作為主要承力構(gòu)件；我國二重建造的8萬噸模鍛液壓機（見圖2）和法國的6.5萬噸多向模鍛液壓機（

16、見圖3）均以“C”形鉤頭板為主要受力構(gòu)件。這種“C”形或者“T”形機架的立柱部分均沒有螺栓聯(lián)接孔，這樣就能夠大幅增加立柱部分的有效斷面，不僅可以節(jié)省材料，降低成本，而且還能夠解決加工、制造、安裝、運輸?shù)葐栴}，減少應(yīng)力集中現(xiàn)象出現(xiàn)，提高了機架的強度。圖2二重集團的800MN模鍛液壓機實物圖圖3法國650MN多向模鍛液壓機第2章 液壓機中液壓缸的設(shè)計計算2.1 液壓機基本技術(shù)參數(shù)表2-1 液壓機的主要設(shè)計參數(shù)參 數(shù) 項參 數(shù)主工作缸4×1.5MN垂直穿孔缸2MN回程缸4×0.3MN穿孔回程缸2×0.2MN同步缸4×0.1MN系統(tǒng)壓力45MPa主工作缸、垂直穿

17、孔缸工作速度090mm/s可調(diào)液壓缸空程和回程工作速度0200mm/s可調(diào)主工作缸行程500mm垂直穿孔缸行程600mm2.2 液壓缸設(shè)計概述在液壓機中，利用高壓液體具有的壓力能生成需要機械功的主要執(zhí)行元件即為液壓缸，液壓缸所受載荷復雜，變化十分頻繁，如果液壓缸設(shè)計不合理、加工制造精度低或者使用不恰當，就會導致其過早損壞甚至報廢。其中主工作缸的性能直接關(guān)系到整臺設(shè)備的使用，若因為設(shè)計不當而在使用過程中出問題，不僅維修重造的費用巨大，還要嚴重影響生產(chǎn)，甚至危及人身安全。 液壓缸的型式及特點液壓缸部件通?？梢苑譃橹健⒒钊胶筒顒邮饺N。一般根據(jù)液壓機總體結(jié)構(gòu)、缸的總壓力大小及工作條件的要求來選

18、擇。1.柱塞式液壓缸 在水壓機中應(yīng)用最多，廣泛用于主工作缸、回程缸、工作臺移動缸及平衡缸等處。結(jié)構(gòu)簡單、制造容易，但只能單方向作用，反方向運動則需要用回程缸來實現(xiàn)。2.活塞式液壓缸 活塞在運動的兩個方向上都需要密封，因此缸的內(nèi)表面在全長上均需加工，精度及光潔度要求較高，結(jié)構(gòu)比較復雜，故在水壓機中應(yīng)用不多，僅在頂出缸和其他輔助機構(gòu)中采用，在中小型油壓機上應(yīng)用普遍。3.差動柱塞式液壓缸多用于回程缸，該結(jié)構(gòu)多一處密封，但當回程缸裝于上橫梁上時，與活動橫梁的連接比較簡單。本設(shè)計中的工作缸選用的是柱塞式液壓缸，這種形式在液壓機中應(yīng)用最廣，其結(jié)構(gòu)簡單，中間安裝有導向套和密封裝置，柱塞不與缸內(nèi)壁接觸，缸內(nèi)壁

19、大部分可以不加工或粗加工，相對其他形式的液壓缸容易制造。柱塞式液壓缸只能單向作用，反向運動需要靠回程缸作用實現(xiàn)，本設(shè)計在液壓機兩側(cè)各加一個回程液壓缸，回程缸也采用柱塞式結(jié)構(gòu)。 液壓缸的支承形式1.法蘭支承及固定 液壓缸以法蘭支承并安裝在橫梁內(nèi)，由缸外壁的環(huán)形面積與橫梁配合，缸內(nèi)進入高壓液體時，通過法蘭與橫梁的接觸面將反力傳給橫梁，液壓缸本身則靠法蘭上的一圈螺釘固定在橫梁上。這種結(jié)構(gòu)的缺點是缸壁法蘭過渡區(qū)存在應(yīng)力集中，易于疲勞損壞。2.缸底支撐及固定液壓缸直接靠缸底固定在橫梁上。這種缸不需要法蘭，消除了法蘭區(qū)的應(yīng)力集中，并可減少缸體毛坯尺寸。缺點是壓機高度有較大增加，缸底與橫梁的接觸情況不易測量

20、。在大型模鍛壓機上使用較多。3.法蘭支承缸底固定這種支承形式的缸底用大螺母固定，要求缸的尺寸不能很大。本設(shè)計中工作缸采用法蘭支承并固定的方式，工作缸缸體安裝在橫梁內(nèi)，以其法蘭部分支承并固定在橫梁下表面，由法蘭的環(huán)形上表面與橫梁配合，這種固定與支撐方式的優(yōu)點是機器總高度相對較低，有利于增加結(jié)構(gòu)的縱向剛度。工作缸本身依靠法蘭上周向分布的螺栓固定在橫梁上，工作時的作用力通過環(huán)形接觸面?zhèn)鬟f，因此法蘭到缸外壁的過渡處存在應(yīng)力集中，易疲勞破壞，以往液壓缸破壞也多出現(xiàn)在這個部位，針對此處有很多研究，本文借鑒這些研究成果對法蘭到缸外壁的過渡處進行了設(shè)計?；爻谈撞捎玫氖欠ㄌm支承缸底固定的形式。 缸體材料的選擇為

21、了使液壓機結(jié)構(gòu)緊湊，應(yīng)使液壓缸外徑盡可能減小。一般來說，總壓力不變時，提高液體工作壓力，液壓缸的外徑將減??；但是如果缸的材料不變，則當液體壓力增加到某一數(shù)值后，缸的外徑反而會增大。如缸內(nèi)徑為R1 ，外徑為 R2 ，液壓壓力為p則由為對應(yīng)的最佳壓力。進一步分析缸的重量與液體壓力之間的關(guān)系，可以發(fā)現(xiàn)當液體壓力比pz 略為降低一些時，缸外徑雖然稍有增加，但缸的重量卻減輕了。因此對應(yīng)于某一缸的材料，液體工作壓力不宜超過最佳壓力Pz ，一般采用合理壓力。根據(jù)我國液壓標準，一般常用壓力為20MPa和32MPa，常用材料為ZG237-500,35,45,20MnMo等，對于這些材料，在（280360）MPa

22、范圍內(nèi)可取為110-150MPa。五、主要參考文獻 1張俊杰800MN模鍛液壓機本體結(jié)構(gòu)分析D 燕山大學碩士學位論文，2012.52陳俊.大型模鍛壓機C型機架安裝關(guān)鍵技術(shù)研究D 重慶大學碩士學位論文，2012.53王兆祥, 俞新陸. 模鍛液壓機整體剛度研究J. 鍛壓技術(shù)，1990，(1):1-2.,4楊固川，于江，陳文，胡孟君，杜俊雷.大型模鍛液壓機機架結(jié)構(gòu)分析研究J 鍛壓技術(shù)，2010.35（3）5Hyoji Yoshimura, Katsuhisa Tanaka. Precision forging of aluminum and steel. Journal of Materials P

23、rocessing Technology 98 (2000) 196-204.6Xian-bin Fu, Bin Liu, Yu-cun Zhang ect.Fault diagnosis of hydraulic system in large forging hydraulic pressJ. Measurement 49 (2014) 3903967S.K. Guan, L.H.Wu, P.Wang.Hot forgeability and die-forging forming of semi-continuously cast AZ70 magnesium alloyJ. Mater

24、ials Science and Engineering A 499 (2009) 1871918劉振堂我國鍛壓機械行業(yè)現(xiàn)狀概況J CMET鍛壓裝備與制造技術(shù)，2011.（4）9姚保森我國鍛造液壓機的現(xiàn)狀及發(fā)展J CMET鍛壓裝備與制造技術(shù)，2005.（3）10Li Nan, XING Shu-ming, BAO Pei-wei.Microstructure and Mechanical Properties of Nodular Cast Iron Produced by Melted Metal Die Forging ProcessJ. Journal of Iron and Steel

25、 Research, Intenational, 2013, 20(6): 58-6211高璐，崔明亮，趙石巖，金淼800 MN模鍛液壓機組合預緊機架危險點分析J 重型機械，2012.No312田會然.800MN多向模鍛液壓機本體結(jié)構(gòu)設(shè)計及分析D.燕山大學碩士學位論文，2006.513Xingwei Zheng, Jie Dong, Dongdi Yin ect.Forgeability and die-forging forming of direct chill casting MgNdZnZr magnesium alloyJ. Materials Science and Enginee

26、ring A 527 (2010) 3690369414金淼，魏慶媛，董曉傳，郭寶峰C形板預應(yīng)力組合框架的預緊梁形狀優(yōu)化J 中國機械工程，2013.24（23）15俞新陸等. 液壓機的結(jié)構(gòu)與控制M. 北京: 機械工業(yè)出版社,1989:38-48.16楊固川，胡孟君，于江，陳文，杜俊雷.大型模鍛液壓機機架C形板設(shè)計研究J 鍛壓技術(shù)，2012.37（2）您好，為你提供優(yōu)秀的畢業(yè)論文參考資料，請您刪除以下內(nèi)容，O(_)O謝謝！A national survey was recently launched to evaluate&#

27、160;the eye health of Chinese children andteenagers.On June 6, China's annual National Day for Eye Care, the China Youth Development ServiceCenter and Zhejiang Medicine, a 

28、;leading listed Chinese pharmaceutical company, jointlyannounced the kickoff of the survey.In about one month, a questionnaire compiled by top eye care medical experts in China

29、0;willbe distributed through multiple online partners, including H, as well asthrough offline survey events held in universities, middle schools and primary schools acrossthe country.A&

30、#160;report will be released based on the survey statistics and analysis, and most importantly,guidelines for parents and youth on how to care for the eyes and prevent

31、60;myopia  agrowing problem in China's digitized society, will also be attached on the report."Myopia is not only a disease that makes people see things blurrily,

32、0;but also leads to severecomplications, such as glaucoma (increased pressure within the eyeball), and can causeblindness," said Zhou Yuehua, an established eye care specialist

33、0;with Beijing TongrenHospital."It is very important for parents and children to know about the risk and care for their eyes."There are about 450 million myopia pati

34、ents in China. Among Chinese myopia patients,30million are severe patients, according to ZhouThe prevalence of myopia among high school and college students is more than 70

35、60;percent,and the situation is continuously worsening, he added.Sun Zhu, director with the China Youth Development Service Center, said long hours ofstudy, lack of exercise, espec

36、ially outdoor activities, and attachment to electronic screen aresome of the top reasons behind the widespread myopia problems, and the increase ofyounger patients, although China&

37、#160;has made great progress in improving the hardwarefacilities and lighting conditions in schools.He said he hopes the survey will alert people on the threatening situation, 

38、;and also helpmedical experts to better guideline parents and children's behaviors to care for eyes, basedon the timely and factual statistics the survey collected.A series

39、0;of follow-up events will also be held in six cities, including Jinan in Shandongprovince, and Changsha in Hunan province, to educate people on how to care for eyes

40、 afterthe survey started. More and more Chinese are jogging to get and stay fit. Most joggers will run alone, but some will jog with friends or even coaches. The Beijing Olympic Forest Park is one of the most popular spots. It is packed with runners in the afternoon, usually after wor

41、k, and at weekends. Jogging after a whole day's work can be a way to unwind. It is true for He Wenjun, whose workplace is right near the forest park. She discovered her athletic aptitude at the age of seven, when she began playing tennis. Then she turned to jogging, and she has persevered with i

42、t for 10 years. "I come to jog almost every day after work, whenever I have time. I think jogging is good for my health. And for me, a girl, it helps me to achieve to eternal goal, to keep slim," He said. He says she prefers jogging alone, so she can focus better. She loves jogging, even d

43、uring Beijing's smoggy days. "If the smog is severe, I'll hold off jogging for a while. But if I really want to get away from work, I'll wear a mask, or just ignore the smog and go on jogging," she said. For those who are not so athletic, jogging also has its attractions. Wu Ho

44、ubin started roughly two years ago, when he was severely obese. Within two months, his weight dropped from 82 kilograms to 64 kilograms. The success helped him recover health, and he has made friends. "Jogging does not require speed, but stamina. If you want to stick to the game, you need to ta

45、ke it as a mission, a habit, and then eventually a hobby," Wu said. But persevering with jogging is not always easy. Jogging is beneficial for heart-lung function, and the skeletal system, but doctors say improper technique damages the joints, especially the knees and ankles. "Excessive jo

46、gging wears down the body, and harms one's health. Poor technique harms the muscles and skeleton, and can cause secondary injures. And, jogging in a bad environment can cause circulation problems," said Lu Zhiyong, attending doctor, Sports Hospital, General Admin. of Sports.Dr. Lu has some

47、tips for joggers, and those who are thinking of taking it up.He says people should first evaluate their physical condition, to decide the amount and type of exercise, and jogging in the open air is better running on a treadmill. Conrad Macao will run special programs for the entire month of October

48、this year to support the Hong Kong Cancer Fund's Pink Revolution, an annual campaign that seeks to raise awareness and funds for breast cancer research, the hotel recently announced. A major sponsor of the campaign for three years in a row, Conrad Macao has pledged to donate a portion of its pro

49、ceeds to the fund, including those collected from selling its popular bear and rubber duck merchandise, in limited pink editions. Pink is the theme for floral arrangements and decorations in the hotel in October. In addition, on Fridays that month, members of the management and staff will add someth

50、ing pink to their uniforms, regular e-mails and handwritten guest cards. "Breast cancer is the most prevalent type of cancer among women in Hong Kong and is also of significant concern in Macao and around the world, regardless of age," general manager Bede Barry said in a statement. The ho

51、tel has enlisted the support of a number of international and local celebrities to help drive the cause, including South Korean actor Jung Suk Won. This year, a lucky guest who stays at the hotel during the campaign and also donates money for the cause will win a necklace specially designed by Arte

52、Madrid, a Spanish jewelry brand. Women should strive to balance quality of work and life, and have children at a young age. As a doctor I see much suffering because of this imbalance. Xiao Ying, 36, works for a large law firm. Her job means lots of travel, a heavy caseload and a large number of meet

53、ings, so her schedule is hectic. She has been pregnant twice, but had abortions on both occasions because she felt her busy, high-pressure career wasn't conducive to raising a child. She planned to have children once she had achieved career success so she could provide a stable environment for h

54、er baby. After 10 years, Xiao felt the time was right, and she tried to conceive for about six months, but was unable to become pregnant. I conducted comprehensive physical checkups. The results suggested that Xiao's ovarian function has declined and a bilateral oviduct blockage has occurred, me

55、aning that in vitro fertilization is her only option. So, after reducing her workload, Xiao underwent IVF treatment. Luckily, she got pregnant after just one treatment cycle, but later experienced vaginal bleeding, and rushed to the hospital. I told her to rest and carry on with the treatment (to pr

56、event a miscarriage). As Zubin Zarthoshtimanesh, a yoga guru, demonstrated postures at a high school stadium in Dujiangyan city, Sichuan province, some 200 students sat on colorful mats watching him closely. It was part of the first India-China international yoga festival in the provincial capital,

57、Chengdu, in Southwest China, where more than 1,000 fans from home and abroad gathered for lessons from 20 leading practitioners of the ancient Indian regimen, from June 17-21. Yoga is to India what perhaps tai chi is to China. Many countries other than India and China, also held the first World Yoga

58、 Day on June 21, after the United Nations last year agreed to Indian Prime Minister Narendra Modi's suggestion that a special day be marked in the year for the global practice of the stress-busting regimen, which is already a multibillion dollar industry in the United States. Modi said in the sp

59、eech: "Yoga is an invaluable gift of India's ancient tradition. . It is not about exercise but to discover the sense of oneness with yourself, the world and nature."Zarthoshtimanesh, who runs his own yoga center, Iyengar Yogabhyasa, in the Indian financial capital of Mumbai, says: &quo

60、t;Chinese students are very respectful. For me, all students are the same no matter what their race is and where they come from. The most important thing is to remove mental walls." Zarthoshtimanesh learned yoga from the late Yogacharya Iyengar and traveled with the master to different countrie

61、s. Consulate General of India in southern China's Guangzhou city organized the Chengdu festival. A terrifying wooden bridge in China has just been replaced by a glass one. This, the worlds longest glass-bottomed walkway, is located in Shiniuzhai Geopark in Hunan, and spans 300m (984f) and is 180

62、m (590f) above ground. The floor is made of double-layered glass that is 24mm (0.94in), and is reportedly 25 times stronger than regular window glass. The bridge had previously been made of wood, linking the two peaks of Stone Buddha Mountain, but 11 engineers working 12 hours a day converted it to

63、glass. Previously, you were considered brave if you steeled yourself to cross the wooden walkway; now, with its glass bottom, the bridge is already being referred to as “hero bridge.” The popular chain's longtime executive chef embraces mapo tofu and other exotic elements for the burger-driven m

64、enu, Liu Zhihua reports.At the age of 37, Shanghai native Lin Zhengu has become a star as a Western cuisine chef in the Chinese metropolis, a city that has a wealth of Western restaurants. The executive chef of Blue Frog Bar and Grill, a popular burger-based restaurant and bar chain on the Chinese mainland, Lin is the soul of the restaurant franchise's team of more than 550 chefs. Many of the franchise's most popular d