1、We will continue to improve the panys internal control system, and steady improvement in ability to manage and control, optimize business processes, to ensure smooth processes, responsibilities in place; to further strengthen internal controls, play a control post independent oversight role of evalu

2、ation plying with third-party responsibility; to actively make use of internal audit tools detect potential management, streamline, standardize related transactions, strengthening operations in accordance with law. Deepening the information management to ensure full munication zero resistance. To co

3、nstantly perfect ERP, and BFS+, and PI, and MIS, and SCM, information system based construction, full integration information system, achieved information resources shared; to e*pand Portal system application of breadth and depth, play information system on enterprise of Assistant role; to perfect d

4、aily run maintenance operation of records, promote problem reasons analysis and system handover; to strengthening BFS+, and ERP, and SCM, technology application of training, improve employees application information system of capacity and level. Humanistic care to ensure zero. To strengthening Human

5、ities care, continues to foster pany wind clear, and gas are, and heart Shun of culture atmosphere; strengthening love helped trapped, care difficult employees; carried out style activities, rich employees life; strengthening health and labour protection, organization career health medical, control

6、career against; continues to implementation psychological warning prevention system, training employees health of character, and stable of mood and enterprising of attitude, created friendly fraternity of Humanities environment. To strengthen risk management, ensure that the business of zero risk. T

7、o strengthened business plans management, will business business plans cover to all level, ensure the business can control in control; to close concern financial, and coal electric linkage, and energy-saving scheduling, national policy trends, strengthening track, active should; to implementation St

8、ate-owned assets method, further specification business financial management; to perfect risk tube control system, achieved risk recognition, and measure, and assessment, and report, and control feedback of closed ring management, improve risk prevention capacity. To further standardize trading, and

9、 strive to achieve according to law, standardize and fair. Innovation of performance management, to ensure that potential employees zero fly. To strengthen performance management, process control, enhance employee evaluation and levels of effective munication to improve performance management. To fu

10、rther quantify and refine employee standards . Work, full play party, and branch, and members in five type Enterprise construction in the of core role, and fighting fortress role and pioneer model role; to continues to strengthening four good leadership construction, full play levels cadres in enter

11、prise development in the-門(mén)急診醫(yī)技樓外腳手架采用懸挑式單排腳手架，根底回填后改為落地式雙排腳手架，腳手架搭設(shè)高度為23m。病房醫(yī)技樓外腳手架采用懸挑雙排腳手架，分四次懸挑of backbone backbone role; to full strengthening members youth work, full play youth employees in pany development in the of force role; to improve independent mission against corruption work level, str

12、engthening on enterprise business key link of effectiveness monitored. , And maintain stability. To further strengthen publicity and education, improve the overall legal system. We must strengthen safety management, establish and improve the education, supervision, and evaluation as one of the traff

13、ic safety management mechanism. To conscientiously sum up the Olympic security controls, promoting integrated management to a higher level, higher standards, a higher level of development. Employees, today is lunar calendar on December 24, the o* Bell is about to ring, at this time of year, we clear

14、ly feel the pulse of the * power generation pany to flourish, to more clearly hear * power generation panies mature and symmetry breathing. Recalling past one another across a railing, we are enthusiastic and full of confidence. Future development opportunities, we more e*citing fight more spirited.

15、 Employees, let us together across 2013 full of challenges and opportunities, to create a green, low-cost operation, full of humane care of a world-class power generation pany and work hard! The occasion of the Spring Festival, my sincere wish that you and the families of the staff in the new year,

16、good health, happy, happyPAGE - 8 -. z. / v .目 錄設(shè)計(jì)依據(jù) 1二、 工況分析 1三、 初步確定油缸參數(shù)，繪制工況圖 4四、 確定液壓系統(tǒng)方案和擬訂液壓系統(tǒng)原理圖 7五、 選擇液壓元?dú)饧?9六、 驗(yàn)算液壓系統(tǒng)性能12七、 心得體會(huì) 14八、 參考文獻(xiàn) 15一、設(shè)計(jì)依據(jù)：下面將按照這一流程圖來(lái)進(jìn)展本次液壓課程設(shè)計(jì)。設(shè)計(jì)一專用銑床的液壓系統(tǒng)。工作臺(tái)作往復(fù)直線運(yùn)動(dòng)，要*現(xiàn)：快進(jìn)工進(jìn)快速退回。最大切削力F=9000N；銑床工作臺(tái)重量G1=3000N，工件及夾具最大重量為G2=1000N；行程長(zhǎng)度L=400mm工進(jìn)和快進(jìn)展程均為200mm，快進(jìn)、快退的速度均為

17、4.5m/min，工作臺(tái)的工進(jìn)速度可調(diào)601000mm/min；啟動(dòng)、減速、制動(dòng)時(shí)間t=0.05s;該動(dòng)力滑臺(tái)采用水平放置的平導(dǎo)軌。靜摩擦系數(shù)fs0.2；動(dòng)摩擦系數(shù)fd0.1。二、工況分析液壓系統(tǒng)的工況分析是指對(duì)液壓執(zhí)行元件進(jìn)展運(yùn)動(dòng)分析和負(fù)載分析，目的是查明每個(gè)執(zhí)行元件在各自工作過(guò)程中的流量、壓力、功率的變化規(guī)律，作為擬定液壓系統(tǒng)方案，確定系統(tǒng)主要參數(shù)壓力和流量的依據(jù)。負(fù)載分析一外負(fù)載 =9000N其中表示最大切削力。對(duì)于專用銑床銑削時(shí)銑刀所承受的主切削力大小單位N為： (N)式中 P 單位切削力 f 每轉(zhuǎn)進(jìn)給量mm/r 背吃刀量mm下面將進(jìn)展具體參數(shù)的計(jì)算：由公式 可得 其中表示每分鐘進(jìn)給速

18、度，n表示銑刀的轉(zhuǎn)速 由設(shè)計(jì)依據(jù)可知 n=300r/min 工進(jìn)速度=601000mm/min，故我們?nèi)?300mm/min。對(duì)于單位切削力P，由以下的常用金屬材料的單位切削力表可得，我們選P=2000。 表1-1類別材料牌號(hào)單位切削力P 鋼易切鋼Y40Mn1700構(gòu)造鋼45200040Cr不銹鋼1Cr17Ni92500 鑄鐵灰鑄鐵HT2001140鑄造合金鑄造錫青銅ZcuSn5Pb5Zn5700鑄造鋁合金ZALSn7Mg720對(duì)于銑削背吃刀量,我們選用硬質(zhì)合金銑刀，查銑工計(jì)算手冊(cè)可得，取=1.5mm。根據(jù)以上的公式 可得：因?yàn)?000=3185N，所以選取的適宜二阻力負(fù)載 靜摩擦力：FPS=

19、G1+G2fs 其中 Ffs靜摩擦力N G1、G2工作臺(tái)及工件的重量N fs靜摩擦系數(shù) 由設(shè)計(jì)依據(jù)可得：Ffs=G1+G2fs=(4000+1800)*0.2=1160N 動(dòng)摩擦力Ffd=G1+G2fd 其中 Ffd動(dòng)摩擦力N fd動(dòng)摩擦系數(shù) 同理可得： Ffd=G1+G2fd=(4000+1800)*0.1=580N三慣性負(fù)載 機(jī)床工作部件的總質(zhì)量m=G1+G2/g=5800/9.81=592kg 慣性力Fm=ma=N 其中：a執(zhí)行元件加速度 m/s ut執(zhí)行元件末速度 m/s u0執(zhí)行元件初速度m/s t執(zhí)行元件加速時(shí)間s 因此，執(zhí)行元件在各動(dòng)作階段中負(fù)載計(jì)算如下表2-2所示：工況油缸負(fù)載

20、N負(fù)載值N啟動(dòng)F=Ffs1160加速F=Ffd+Fm1073快進(jìn)F=Ffd580工進(jìn)F=Ffd+Fc3580快退F=Ffd580圖2銑床液壓缸速度圖按上表的數(shù)值繪制負(fù)載如下圖。 對(duì)于速度而言，設(shè)計(jì)依據(jù)中已經(jīng)有了明確的說(shuō)明，所以按照設(shè)計(jì)依據(jù)繪制如下：銑床機(jī)床液壓缸負(fù)載圖圖1銑床液壓缸負(fù)載圖三、初步確定油缸參數(shù)，繪制工況圖1、初選油缸的工作壓力、 由上可以知道，銑床的最大負(fù)載F=3580N，根據(jù)下表可得： 表 3-3 按負(fù)載選擇液壓執(zhí)行元件的工作壓力載荷/kN50工作壓力Mpa=57 選系統(tǒng)的工作壓力P1=2Mpa。 由設(shè)計(jì)要求可知，導(dǎo)軌要求快進(jìn)、快退的速度相等，故液壓缸選用單活塞桿式的，快進(jìn)時(shí)采

21、用差動(dòng)連接，且液壓缸活塞桿直徑d0.7D。快進(jìn)和工進(jìn)的速度換接用三位四通電磁閥來(lái)實(shí)現(xiàn)。 銑床液壓系統(tǒng)的功率不大，為使系統(tǒng)構(gòu)造簡(jiǎn)單，工作可靠，決定采用定量泵供油。考慮到銑床可能受到負(fù)值負(fù)載，故采用調(diào)速閥的進(jìn)油節(jié)流加背壓閥的調(diào)速回路，所以回油路上具有背壓P2，取背壓P2=0.5Mpa。2、計(jì)算油缸尺寸 可根據(jù)油缸的構(gòu)造及連接方式計(jì)算油缸的面積、油缸直徑D及活塞桿直徑d計(jì)算出后應(yīng)按標(biāo)準(zhǔn)予以圓整，然后再計(jì)算油缸的面積：此時(shí)由工進(jìn)時(shí)的負(fù)載值按計(jì)算公式計(jì)算液壓缸面積： 在將這些直徑按照國(guó)標(biāo)圓整成標(biāo)準(zhǔn)值得：D=0.06m, d=0.04m由此就求得液壓缸兩腔的實(shí)際有效面積為，。3、油缸各工況的壓力、流量、功

22、率的計(jì)算1、工進(jìn)時(shí)油缸需要的流量Q工進(jìn) Q 工進(jìn)= A1U工進(jìn)=A1:工進(jìn)時(shí)油壓作用的面積 A1:工進(jìn)時(shí)油壓作用的面積 U工進(jìn)工進(jìn)時(shí)油缸的速度 mm/min(2)、快進(jìn)時(shí)油缸需要的流量Q快進(jìn) 差動(dòng)連接時(shí):Q快進(jìn)=(A1-A2) U快進(jìn) = A1、A2分別表示油缸活塞腔、活塞桿截面積 m U快進(jìn)油缸快進(jìn)時(shí)的速度mm/min、快退時(shí)油缸需要的流量Q快退 Q快退= A2U快退 = U快退油缸退回時(shí)的速度 mm/min(4)、工進(jìn)時(shí)油缸的壓力 P2為工進(jìn)時(shí)回油腔的背壓,上面已經(jīng)選取為0.5Mpa。5、快進(jìn)時(shí)油缸壓力這里：F分別表示快速啟動(dòng)、加速、快速時(shí)油缸的推力， P分別表示快速啟動(dòng)、加速、快速時(shí)油缸

23、的壓力。表示管路中壓力損失大小，這里我們?nèi)≈禐?.3Mpa。6、快退時(shí)油缸壓力F分別表示快速啟動(dòng)、加速、快速時(shí)油缸的推力，P分別表示快速啟動(dòng)、加速、快速時(shí)油缸的壓力。P2的值為0.5MPa油缸工作循環(huán)中各階段的壓力、流量、功率實(shí)際值如表2所示：表4-4 液壓缸在不同工作階段的壓力、流量和功率值工況負(fù)載F/N回油腔壓力進(jìn)油腔壓力輸入流量q/輸入功率P/kW快進(jìn)(差動(dòng))啟動(dòng)116000.96加速10731.26快進(jìn)5800.860.00630.09 工進(jìn)85800.51.600.00080.021快退啟動(dòng)116000.77加速10730.51.61快退5801.280.00780.166由以上所計(jì)

24、算的數(shù)據(jù)我們繪制出工況圖如下所示：圖3液壓缸工況圖四、確定液壓系統(tǒng)方案和擬訂液壓系統(tǒng)原理圖(一)確定油源及調(diào)速方式由以上的計(jì)算可以知道，銑床液壓系統(tǒng)的功率不大，工作負(fù)載的變化情況很小，因此，為使系統(tǒng)構(gòu)造簡(jiǎn)單，工作可靠，決定采用定量泵供油?？紤]到銑床可能受到負(fù)值負(fù)載，故采用回油路調(diào)速閥節(jié)流調(diào)速方式，并選用開(kāi)式循環(huán)。從工況圖中我們可以清楚的看出，在液壓系統(tǒng)的工作循環(huán)中，液壓缸要求油源提供的流量變化并不是很大，因此工進(jìn)和快進(jìn)的過(guò)程中，所需流量差異較小。故我們選用定量單液壓泵供油。 圖4二選擇根本回路1.選擇換向回路及速度換接方式 由設(shè)計(jì)依據(jù)可以知道，設(shè)計(jì)過(guò)程中不考慮工件夾緊這一工序，并且從快進(jìn)到工進(jìn)

25、時(shí)，輸入液壓缸的流量從6.3L/min降到0.8L/min，速度變化不是很大，所以采用電磁換向閥來(lái)實(shí)現(xiàn)速度的換接。壓力繼電器發(fā)訊，由電磁換向閥實(shí)現(xiàn)工作臺(tái)的自動(dòng)啟動(dòng)和換向。同時(shí)為了實(shí)現(xiàn)工作臺(tái)能在任意位置停頓，泵不卸載，故電磁閥必須選擇O型機(jī)能的三位四通閥，如下列圖5所示：圖5 由于要求工作臺(tái)快進(jìn)與快退速度相等，故快進(jìn)時(shí)采用差動(dòng)連接來(lái)實(shí)現(xiàn)快速運(yùn)動(dòng)回路，且要求液壓缸活塞桿直徑d0.7D。三選擇調(diào)壓回路設(shè)計(jì)過(guò)程中，在油源中采用溢流閥來(lái)調(diào)定系統(tǒng)的工作壓力，因此調(diào)壓?jiǎn)栴}根本上已經(jīng)在油源中解決，無(wú)須在另外設(shè)置調(diào)壓系統(tǒng)。這里的溢流閥同時(shí)還能起到平安閥的作用。1、組合成液壓系統(tǒng)圖 將上面所選的液壓根本回路組合在

26、一起，便可得到以下的液壓系統(tǒng)原理圖。同時(shí)電磁鐵的動(dòng)作順序表如下： 表5-5液壓專用銑床電磁鐵動(dòng)作順序表 工序1Y2Y3Y5Y 工作缸快進(jìn)+工作缸工進(jìn)+工作缸快退+ 圖6 專用銑床液壓系統(tǒng)原理圖1-油箱；2-過(guò)濾器；3-葉片泵；4-溢流閥；5-三位四通電磁換向閥6單向調(diào)速閥；7-兩位三通電磁換向閥；8-工作缸；9-壓力繼電器五、選擇液壓元?dú)饧簤罕玫倪x擇 由以上的設(shè)計(jì)可以得到，液壓缸在整個(gè)工作過(guò)程中的最大壓力是1.61Mpa，如取進(jìn)油路上的壓力損失為0.4Mpa，則此時(shí)液壓泵的最大工作壓力是=1.61+0.4=2.01Mpa。 由以上的計(jì)算可得，液壓泵提供的最大流量是7.8L/min,因?yàn)橄到y(tǒng)較

27、為簡(jiǎn)單，取泄漏系數(shù)，則兩個(gè)液壓泵的實(shí)際流量應(yīng)為： 由于溢流閥的最小穩(wěn)定溢流量為3L/min，而工進(jìn)時(shí)輸入到液壓缸的流量是3.8L/min，由流量液壓泵單獨(dú)供油，所以液壓泵的流量規(guī)格最少應(yīng)為6.8L/min。根據(jù)以上的壓力和流量的數(shù)值查閱機(jī)械設(shè)計(jì)手冊(cè)，最后選用YB1-6.3型單葉片液壓泵，其排量大小為6.3ml/r,當(dāng)液壓泵的轉(zhuǎn)速為1450r/min時(shí)，該液壓泵的理論流量為9.14L/min。取液壓泵的容積效率為，則液壓泵的實(shí)際流量大小為：由于由以上的計(jì)算過(guò)程中，我們知道了液壓缸在快退時(shí)的輸入功率最大，此時(shí)液壓泵的工作壓力是1.28+0.4進(jìn)油路上的壓力損失=1.68Mpa，流量為6.8L/mi

28、n，查表可得，取液壓泵的總效率，則液壓泵驅(qū)動(dòng)電機(jī)所需的功率為 根據(jù)以上的數(shù)據(jù)查機(jī)械設(shè)計(jì)手冊(cè)選用Y801型電動(dòng)機(jī)，其額定功率為0.55kW，額定轉(zhuǎn)速為1200r/min。二閥類元?dú)饧拜o助元?dú)饧倪x擇表5-5元?dú)饧男吞?hào)及規(guī)格 根據(jù)閥類及輔助元?dú)饧谟吐返淖畲蠊ぷ鲏毫屯ㄟ^(guò)的最大實(shí)際流量，可選擇這些器件的型號(hào)和規(guī)格如下表：序號(hào)元件名稱額定流量L/min額定壓力(Mpa)質(zhì)量(kg)型號(hào)1單葉片泵9.26.35.5YB1-6.32三位四通電磁閥256.334D-25BOP3二位三通電磁閥256.323D-25B4單向調(diào)速閥0.05最小3.2QI-10B5溢流閥201.7Y-10B6壓力繼電器0.7DP1-63B7濾油器 162.50.18*U-B16*1008開(kāi)關(guān)閥256.322D-25B三確定油管直徑表6-6液壓缸的進(jìn)出、流量 由于液壓泵在選定之后液壓缸在各個(gè)工作階段的進(jìn)、出流量已與原來(lái)的數(shù)值不同，所以要重新計(jì)算，計(jì)算如下表4所示：快進(jìn)工進(jìn)快退輸入流量L/min輸出流量(L/min)運(yùn)動(dòng)速度(m/min)由上表中的數(shù)值，按照書(shū)中推薦的油液