1摘 要汽車起重機(jī)式工程機(jī)械產(chǎn)品中重要組成部分，它由于機(jī)動(dòng)性好而被廣泛應(yīng)用于礦山、建筑、港口、油田等領(lǐng)域。主要由變幅機(jī)構(gòu)、伸縮機(jī)構(gòu)、起升機(jī)構(gòu)、回轉(zhuǎn)機(jī)構(gòu)、支腿機(jī)構(gòu)組成。本文講述了 QY-20 汽車起重機(jī)液壓系統(tǒng)的設(shè)計(jì)。首先，通過對(duì)汽車起重機(jī)總體構(gòu)成及工作原理進(jìn)行分析，在此分析基礎(chǔ)上提出了提液壓系統(tǒng)各功能回路的設(shè)計(jì)方案，并把各回路組合后得出了液壓系統(tǒng)原理圖；接著，設(shè)計(jì)并選擇了液壓系統(tǒng)各液壓元件并進(jìn)行了相應(yīng)計(jì)算；然后，對(duì)主要執(zhí)行機(jī)構(gòu)-液壓缸進(jìn)行了設(shè)計(jì)與強(qiáng)度校核；最后，通過 AutoCAD 制圖軟件繪制了本 QY-20 汽車起重機(jī)液壓系統(tǒng)原理圖的非標(biāo)零件裝配圖及主要零件圖。通過本次設(shè)計(jì)，鞏固了大學(xué)所學(xué)專業(yè)知識(shí)，如：液壓與氣動(dòng)傳動(dòng)、機(jī)械原理、機(jī)械設(shè)計(jì)、材料力學(xué)、公差與互換性理論、機(jī)械制圖等；掌握了起重機(jī)械產(chǎn)品的設(shè)計(jì)方法并能夠熟練使用 AutoCAD 制圖軟件，對(duì)今后的工作于生活具有極大意義。關(guān)鍵字：起重機(jī)，起升，支腿，變幅，回轉(zhuǎn)2AbstractAs an important part of automobile crane engineering machinery products, it is widely used in mining, construction, port, oil field and other fields because of its good maneuverability. Mainly consists of variable amplitude mechanism, telescopic mechanism, lifting mechanism, rotating mechanism and supporting leg mechanism.This paper describes the design of hydraulic system of QY-20 truck crane. First of all, based on truck crane overall composition and working principle analysis, this analysis based on the proposed design scheme of hydraulic system and the function of the loop and to each circuit combination obtains the principle diagram of hydraulic system; then, design and selection of hydraulic system and the hydraulic pressure component and the corresponding calculation; then, on the main actuator hydraulic cylinders were design and strength check. Finally, through the AutoCAD drawing software drawn the QY-20 truck crane hydraulic system principle diagram of non-standard parts assembly drawing and main parts figure.Through the design, the consolidation of the University of the professional knowledge, such as: hydraulic and gas dynamic transmission, mechanical principles, mechanical design, mechanics of materials, tolerance and interchangeability theories, mechanical drawing; master the design method of hoisting machinery products and be able to skillfully use AutoCAD drawing software, for future work in life is of great significance.Key words: Crane, Lifting, Supporting legs, Amplitude, Rotation3目 錄摘 要 ...........................................................................................................................................IAbstract.....................................................................................................................................II第 1 章 緒論...............................................................................................................................11.1 研究背景及意義...........................................................................................................11.2 國內(nèi)外汽車起重機(jī)發(fā)展現(xiàn)狀.......................................................................................11.2.1 國內(nèi)發(fā)展現(xiàn)狀......................................................................................................11.2.2 國外發(fā)展現(xiàn)狀......................................................................................................21.3 汽車起重機(jī)的類型........................................................................................................21.4 汽車起重機(jī)對(duì)液壓系統(tǒng)的要求....................................................................................31.5 主要內(nèi)容........................................................................................................................3第 2 章 總體分析.......................................................................................................................52.1 設(shè)計(jì)要求........................................................................................................................52.1.1 功能要求..............................................................................................................52.1.2 主要技術(shù)參數(shù)要求..............................................................................................52.2 結(jié)構(gòu)及功能分析............................................................................................................52.3 工況分析........................................................................................................................72.3.1 運(yùn)動(dòng)分析..............................................................................................................72.3.2 動(dòng)力分析..............................................................................................................82.3.3 負(fù)載分析..............................................................................................................9第 3 章 液壓系統(tǒng)設(shè)計(jì).............................................................................................................103.1 額定壓力的確定..........................................................................................................103.2 基本回路設(shè)計(jì)..............................................................................................................103.2.1 支腿機(jī)構(gòu)回路的設(shè)計(jì)........................................................................................103.2.2 起升機(jī)構(gòu)回路的設(shè)計(jì)........................................................................................113.2.3 變幅機(jī)構(gòu)回路的設(shè)計(jì)........................................................................................113.2.4 伸縮機(jī)構(gòu)回路的設(shè)計(jì)........................................................................................123.2.5 回轉(zhuǎn)機(jī)構(gòu)回路的設(shè)計(jì)........................................................................................123.3 液壓系統(tǒng)原理圖..........................................................................................................13第 4 章 液壓元件的設(shè)計(jì)與選擇.............................................................................................144.1 液壓馬達(dá)和液壓泵的選擇.........................................................................................1444.1.1 卷揚(yáng)馬達(dá)的選擇................................................................................................144.1.2 回轉(zhuǎn)馬達(dá)的選擇................................................................................................144.1.3 泵的選擇............................................................................................................154.2 液壓閥的選擇..............................................................................................................164.3 液壓輔助元件選擇......................................................................................................174.3.1 液壓油的選擇....................................................................................................174.3.2 濾油器的選擇....................................................................................................174.3.3 壓力表的選擇....................................................................................................174.3.4 閥類元件的選擇................................................................................................174.4 液壓油箱的設(shè)計(jì)..........................................................................................................184.5 液壓油管設(shè)計(jì)..............................................................................................................194.5.1 油管通徑的計(jì)算................................................................................................194.5.2 壁厚的計(jì)算........................................................................................................204.6 液壓系統(tǒng)的驗(yàn)算..........................................................................................................214.6.1 壓力損失的驗(yàn)算...............................................................................................214.6.2 發(fā)熱溫升的驗(yàn)算................................................................................................22第 5 章 液壓缸的設(shè)計(jì).............................................................................................................245.1 支腿液壓缸的設(shè)計(jì)......................................................................................................245.1.1 支腿垂直液壓缸................................................................................................245.1.2 支腿水平液壓缸................................................................................................275.2 變幅液壓缸的計(jì)算......................................................................................................285.3 伸縮液壓缸的計(jì)算......................................................................................................29總 結(jié).........................................................................................................................................31參考文獻(xiàn)...................................................................................................................................32致 謝.........................................................................................................................................33