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中國的機械發(fā)展講義-wenkub.com

2025-06-25 23:41 本頁面
   

【正文】 s mechanical science and technology development speed. To the mechanical product largescale, precision, automation and discusses the trend of development. In some aspects has reached or exceeded the world advanced level. Generally speaking, currently China mechanical science and technology achievement is huge, developing fast, high level of unprecedented. In this period, China has no end of mechanical science and technology will develop to a higher level. As long as we can adopt the correct policy, with good technology development and innovation, our machinery industry and mechanical technology can revitalize, leading to the development trend of mechanical industry. Just small ramming machinery: In the 1960s, China mechanical very small tamp lack, many small venues ramming basically USES artificial ramming. Early 1960s, changsha construction machinery institute and Beijing architectural engineering institute, etc., the technical innovation achievements in mass on the basis of summing up Chinese characteristic invented the breaststroke ramming machine, 1962 exceeded national science and technology. The breaststroke ramming machine structure is simple, easy to use and maintenance in 1960s, soon became the dominant products to consolidate machinery. According to not plete count breaststroke tamp cumulative yield reached more than 50,000 machine, in the economic development of our country has played an important role. Since 197039。 1990年,北京金屬結(jié)構(gòu)廠開始采用數(shù)控精密切割和具有光電跟蹤及數(shù)控尋蹤讀入自動編程的大功率等離子切割技術(shù)。 1966年,北京金屬結(jié)構(gòu)廠開發(fā)出了使被焊球體旋轉(zhuǎn)的埋弧自動焊。 1984~1990年,北京市熱處理研究所研究成功真空熱處理、氣體滲碳微機控制技術(shù)(與北京航空航天大學(xué)合作)、稀土軟氮化、粉末冶金制品表面強化、煤油加甲醇小滴量法微機可控滲碳、固體滲硼、滲碳過程微機輔助工藝設(shè)計及跟蹤控制系統(tǒng)等熱處理新技術(shù),并應(yīng)用于生產(chǎn)。 1978年,北京機床研究所研究完成機床導(dǎo)軌表面接觸淬火工藝及設(shè)備、淬火質(zhì)量檢查技術(shù)條件的研究。 熱處理 1949年前,北京已采用電爐、鹽溶爐、熱電偶等手段進行零件退火、回火、淬火、正火、調(diào)質(zhì)、滲碳等熱處理。 鍛壓 1959年,北京第二通用機械廠(后改名北京重型機器廠)建成2500噸水壓機。1965年,開始采用塑料模型。 就機械加工而言:熱加工 鑄造 據(jù)考古發(fā)現(xiàn),在北京平谷、昌平、房山等處曾出土了公元前16世紀(商代)的青銅禮器。由于振動沖擊夯具有壓實效果好、生產(chǎn)率高、體積和重量小、輕便靈活等突出特點,深受用戶歡迎,得到了迅速的推廣使用,并很快發(fā)展到資江機器廠、新鄉(xiāng)第三機床廠和津市洞庭工程機械廠等幾十家企業(yè)生產(chǎn)。隨后義烏建筑機械廠、四平建筑機械廠、安陽振動器廠、津市洞庭工程機械廠等多家企業(yè)都開始生產(chǎn)振動平板夯。 1964年,長沙建設(shè)機械研究所開發(fā)了HB120型內(nèi)燃式夯實機,開始由上海工程機械廠生產(chǎn),后來主要由津市洞庭工程機械廠生產(chǎn),年產(chǎn)量200臺左右。 上世紀60年代初期,長沙建設(shè)機械研究所與北京建筑工程學(xué)院等單位合作,在群眾性技術(shù)革新成果的基礎(chǔ)上總結(jié)發(fā)明了具有中國特色的蛙式夯實機,1962年獲國家科技發(fā)明獎??偟膩碚f,就目前而言中國機械科學(xué)技術(shù)的成就是巨大的,發(fā)展速度之快,水平之高也是前所
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