【正文】 。油口孔大多屬于薄壁孔（指孔的長度與直徑之比 ?dl 的孔）。A 液壓缸的內(nèi)徑（該處采用最外面液壓缸的內(nèi)徑） m3 ； V液壓缸的運(yùn)動(dòng)速度， m/s。 ??A m3 V= m/s。主要包括：缸體與缸蓋的連接結(jié)構(gòu)、活塞桿與活塞的連接結(jié)構(gòu)、密封裝置、排氣裝置、及液壓缸的安裝連接結(jié)構(gòu)等。因此，設(shè)計(jì)中采用了法蘭連接，其優(yōu)缺點(diǎn)如表 38。sQ 剩余鎖緊力，對(duì)載荷變化的聯(lián)接取 39。0 ??? sQ N 因此螺釘?shù)膹?qiáng)度條件為： ? ?lidQdQ ???? ??? 21210 44合 式中 i ? 稱為計(jì)算載荷。 ???l? 許用拉應(yīng)力。 前缸蓋螺釘強(qiáng)度校核： 前缸蓋校核時(shí)，因?yàn)榍岸松w的螺釘最主要的受了是液壓缸上升時(shí)產(chǎn)生的拉應(yīng)力。 ???l? 許用拉應(yīng)力； 上式中 ?n 安全系數(shù)，一般取 ~?n ； 對(duì)于 45 鋼取 ? ? ??l?Mpa?；钊c活塞桿的連接常采用 螺紋連接 ，結(jié)構(gòu)簡單。 根據(jù)該系統(tǒng)的密封要求，速度不是很快，壓力較小，對(duì)溫度的要求較低，中低摩 擦泄露，再結(jié)合各密封元件的特點(diǎn)，為此 缸筒和缸蓋之間 選用 O 型密封圈 ， 活塞與缸蓋之間采用 Y 型密封圈。例如，液壓導(dǎo)軌磨床在加工過程中，如果工作臺(tái)進(jìn)給液壓缸內(nèi)存有空氣，就會(huì)引起工作臺(tái)進(jìn)給時(shí)的顫振和爬行，這不僅會(huì)影響被加工表面的粗糙度和形位公差等級(jí)，而且會(huì)損壞砂輪和磨頭等機(jī)構(gòu)；如果這種現(xiàn)象發(fā)生在煉鋼轉(zhuǎn)爐的傾倒裝置液壓缸中，那將會(huì)引起鋼水的動(dòng)蕩潑出，這是十分危險(xiǎn)的。由于空氣比油輕，總是向上浮動(dòng)，不會(huì)讓空氣有積存的殘留死角。 5）液壓缸的安裝連接結(jié)構(gòu) 該液壓缸由于其工作時(shí)是豎立的，固定方式還要待具體的工作環(huán)境而定， 由于液壓缸缸體不是太長 ， 所以固定了液壓缸的尾部即可達(dá)到固定的目的 。本課題設(shè)計(jì)的液壓式槽型彎板機(jī)采用了多缸同步的 工作 方式 。 淮陰工學(xué)院畢業(yè)設(shè)計(jì)說明書 （論文） 第 24 頁 共 28頁 圖 壓板 圖 3） 壓桿 壓桿將 3 個(gè) 工作缸連成一組，達(dá)到了多缸同步的目的，提高了槽型板成品的質(zhì)量 ，其形狀結(jié)構(gòu)如圖 。 圖 底座圖 7） 模型 模型確定了加工得到槽型板的形狀， 其形狀結(jié)構(gòu)如圖 。 本課題 設(shè)計(jì)的 液壓式槽型彎板機(jī) 解決了多缸同步工作的難題 ，保證了 板料 在壓彎過程中 壓彎程度 的同步。不斷完善彎板機(jī)的結(jié)構(gòu)設(shè)計(jì)，最終設(shè)計(jì)出結(jié)構(gòu)簡單、可行的液壓式槽型彎板機(jī)。 不過 ， 由于 本 人 能力 有限 ，本課題 設(shè)計(jì) 的液壓式槽型彎板機(jī) 還存在著 很多 需要改進(jìn)和完善的地方，有待于后續(xù)開發(fā)和研究。 謹(jǐn)向 系里為我們畢業(yè)設(shè)計(jì)操心和提供各方面支持的老師和同學(xué) 致以最崇高的敬意 ，是你們的關(guān)心才讓我們的畢業(yè)設(shè)計(jì)得以順利進(jìn)行 。80s. We sat on the back of pickup trucks for hours. The sky was blue, and we couldn39。s performers of the troupe still tour the region39。s Liaoning province, decades ago. The solider gave the old man a handmade saddle when they bid farewell. The story inspired Nasun to write Carved Saddle, a song that later became one of his most popular numbers. Now, every year, Nasun recruits young singers and dancers for the troupe. The troupe has also designed a new repertoire, which is mostly based on the daily lives of Mongolian people, especially the lives of nomadic families, and has bined contemporary musical elements with folk songs of the region. Haimu, a 25yearold khoomei (a local variant of overtone singing) singer, joined the troupe three years ago. Along with a sixmember band, he performs fast songs and soft ones that he writes－ all while playing the horsehead fiddle.Although I learned the piano since childhood and grew up listening to various kinds of music, to me, the folk music of Inner Mongolia is the root, he says. Performing in remote villages is pleasant. I feel at home on the boundless grasslands, and the warm people there make me feel fulfilled. The first round of spring auction season in Beijing ended last week, but it failed to create much spring in the art market. Although two pieces of Chinese painting fetched more than 100 million yuan, the decline in trading volume and sa le rate showed a downturn this year. In the ―Grand View: Chinese Painting Highlight‖ session at China Guardian 2022 spring auctions, Pan Tianshou’s representative work Eagle, Rock and Flora hit a record auction price of 279 million yuan, while Li Keran’s masterwork Jinggang Mountain fetched million yuan, an unexpected high in recent years. However, the trading volume fells to billion yuan from billion yuan in the same period the year before. The Huangchen 2022 Spring Auctions, which recorded million yuan in total sales, experienced the same. The section number went down to 5 from 12 pared to last year. According to expert Shao Jianwu, the art market did not attract much excitement this year due to the booming stock market and the persistent problems of fery and fake deals. The two pieces of Chinese painting notched up high price this spring due to their own value not due to a revival in the market. The successful transaction of two works with a hammer price of more than 100 million yuan once again confirms that valuable and rare works of high quality always earn the longlasting high price. Chinese painting and calligraphy is still the pillar of the market. However, the overall sales rate has dropped slightly, which reflects the demand for the ordinary auction goods has weakened,‖ said the president of China Guardian’s Hu Yanyan. Besides, the entry of new buyers also makes certain changes to the direction of purchasing. In a word, the overall market trend is very unpredictable. Although China Guardian 2022 Spring Auctions has achieved remarkable results, it does not mean that the market has walked out of the predicament. We still have to wait for the big economic boom to invigorate the art market.‖ Even so, the hot pursuit of some special items appeared this spring. A special session of China Guardian Spring Auctions titled ―Fine Gilt—Bronze Buddhist Images‖ achieved a great deal with total sales volume of million yuan and 92 percent sale rate. The 5th Shamar Rinpoche Statue from 1617th century of Tibet was sold for million yuan. The Beijing Chengxuan Auctions featured almost 2,800 items of coins and stamps in three sessions with good sale rate. The Huachen Auctions also set a special session of photographs under the condition of largescale decline of auction sessions. There was a palpable dull thud of disappointment that acpanied the return of the imperial entourage of Zhen Huan to her homeland. It followed a couple years of hushed excitement as Chinese fans were fed tidbits about their proud concubine who was supposed to conquer the high ground of the North American market. Zhen Huan is, of course, the title character of The Legend of Zhen Huan, a 2022 television series that swept China off its feet and later took other Asian countries by storm. Two years ago, it was reported that HBO, a premium cable service headquartered in the United States, was going to air it in North America after some modification. Now, a condensed version that provides English subtitles but no dubbing has finally been made available on Netflix for online streaming. This version, highly anticipated as a milestone in China39。s essay titled SelfReliance. If you3