【正文】 nto the cab of a crane.Imagine that a mercial airline pilot had the same training as a certified crane operator. How would you feel the next time you decided to fly? In California, it takes more hours of training to wield a pair of scissors in a hair salon than to operate potentially dangerous lifting machinery. How does this make sense?Riggers and signal persons also need standard training and testing to ensure safety under the hook. Employers usually allow any craft to signal a crane on a jobsite, despite best practices that require only qualified people do so. How is it then that uncertified and untrained people are allowed to signal and rig under the hook of a licensed or certified operator?Tower cranes are particularly risky as urban sites bee more congested, and the risk of a catastrophic event is very high during climbing operations. Yet most towercrane climbing crews are trained in a nontraditional manner, via secondhand knowledge that has been passed down over time. The problem with this type of handmedown knowledge is that it changes over the years, leaving out smallbutimportant details along the way. This osmosis of knowledge leads crews to develop their own tricks for climbing cranes, often forsaking basic safety in an attempt to save time and energy.In many cases, there are no safety devices or alarms to warn of a serious problem. Climbing crews are subjected to pressures that affect safetycritical decisionmaking. It is not unmon for climbs to continue with damaged or leaking hydraulic systems, outofadjustment or jammed guide rollers, often working in the dark and for extended hours. This MacGyver method of climbing, where every jump bees a new adventure, should not be the norm.Climbingframe designs vary among manufacturers, but the operational steps are similar in principle. The climbing process is relatively straightforward, with a mixture of physical work and technical procedure. It is not plex。 as we know it today. As they had actually designed the Motocrane, both knew it inside out and were pleased to pass on this knowledge.In response to the longstanding problems,in which the swinging angle of the hoisted load and the velocity of swinging angle is difficult to measure in engineering practice,a state observer is designed by the use of information about the crane trolley39。最近塔式起重機(jī)倒塌在一個(gè)繁忙的紐約市建筑地盤(pán)應(yīng)敲響警鐘，提醒我們問(wèn)題的存在，并加強(qiáng)我們目前安全的做法。雇主通常允許任何工人發(fā)信號(hào)指揮起重機(jī)上工地 ，盡管最佳做法是需要合格的人這樣做。在黑暗中工作和延長(zhǎng)工作時(shí)間是時(shí)有發(fā)生的。視察員同樣也也須有具體的技術(shù)培訓(xùn)。然。這就是為什么業(yè)界需要規(guī)范的培訓(xùn)，測(cè)試和監(jiān)督，其中包括一個(gè)實(shí)際的評(píng)估能力。攀登人員容易遭受到影響安全性至關(guān)重要的決策所帶來(lái)的壓力。你會(huì)如何感覺(jué)，下一次你決定要坐飛機(jī)？在加利福尼亞州，掌握一對(duì)剪刀在頭發(fā)沙龍比操作有潛在危險(xiǎn)的起重機(jī)械需要更多的時(shí)間訓(xùn)練。據(jù)國(guó)內(nèi)有關(guān)部門(mén)統(tǒng)計(jì)資料表明，%。 series. This consisted of three cranes which, for the first time in history, were mounted on chassis built by the crane manufacturer itselfi The smallest crane, the MC2, could lift tonnes, the MC2 tonnes and the MC3 tonnes. These cranes were delivered to the army by the thousand, and were also mounted on portals for use as harbour cranes (the MC4 model). The war had, of course, taken its toll on the number of ablebodied men available to work in the crane industry and there was a serious shortage of good crane drivers. At Thew, newers were taught crane operations over a twoday course presented by A C Burch, an experienced mechanic and graduate of the Naval Academy, and L K Jenkins. These two gentlemen were probably the originators of 39。s increasingly petitive construction market, to meet the construction needs of many construction panies have bought the tower crane. With the tower crane at the construction site of the widely used by the tower crane accident also caused more and more to people39。在整個(gè)設(shè)計(jì)中由于時(shí)間倉(cāng)促，難免出現(xiàn)不少錯(cuò)誤，望各位老師在設(shè)計(jì)過(guò)程中，第一階段，我們精心收集整理各種資料，提高了對(duì)新知識(shí)的自學(xué)能力，對(duì)資料的搜集整理能力。由于大車(chē)運(yùn)行速度大于80m/min，采用杠桿式限位開(kāi)關(guān)不能提供可靠的保證，故采用無(wú)觸點(diǎn)運(yùn)行限位系統(tǒng)：光電裝置來(lái)保證。11 安全裝置的選擇說(shuō)明電動(dòng)雙梁橋式起重機(jī)有相應(yīng)的電氣保護(hù)裝置以外，還有其他保護(hù)裝置。選用后進(jìn)行強(qiáng)度較核。本設(shè)計(jì)選用了軌道安裝在主梁的正中形式。 根據(jù)結(jié)構(gòu)尺寸和 查手冊(cè)，選用LM8型梅花彈性聯(lián)軸器，其 ；轉(zhuǎn)動(dòng)慣量 滿足要求標(biāo)注：LM8聯(lián)軸器GB/T5272—2002器連接處聯(lián)軸器選擇：浮動(dòng)軸尺寸：d=50mm減速軸高速軸尺寸：d=38mm，L=80 mm選LM7型梅花彈性聯(lián)軸器； 則有： ；轉(zhuǎn)動(dòng)慣量： 滿足要求標(biāo)注：LM7聯(lián)軸器 GB/T 5272—2002（2）低速軸聯(lián)軸器選擇選用聯(lián)軸器公式：=式中：—減速器傳動(dòng)比；=25—機(jī)構(gòu)傳動(dòng)效率；=：減速器低速端尺寸：d=80mm。 選用合理聯(lián)軸器標(biāo)注為：LM12聯(lián)軸器MT12aGB/T 5272— 2002（2）減速器與浮動(dòng)軸的連接處聯(lián)軸器浮動(dòng)軸端尺寸：d=95mm減速器輸入軸：d=90mm L=170mm制動(dòng)輪直徑：D=500 mm根據(jù)以上結(jié)構(gòu)尺寸和T=5328m。 e=. 螺栓預(yù)緊力計(jì)算 因選壓板槽為半圓形，故：. 螺栓強(qiáng)度驗(yàn)算 = =110MPa校驗(yàn)通過(guò)式中：Z—固定鋼絲繩用的螺母數(shù)，取Z=4 d—螺栓螺紋的內(nèi)徑；d= —墊圈與鋼絲繩壓板之間的摩擦系數(shù)，取= t—作用力臂；根據(jù)壓板得t=—螺栓許用拉應(yīng)力，==—螺栓屈服強(qiáng)度；因螺栓材料為Q235；查手冊(cè)得：=206Mpa. 壓板的選取 查手冊(cè)：選取序號(hào)為6的壓板，標(biāo)準(zhǔn)槽標(biāo)注：壓板6GB/T5975—19868 起升機(jī)構(gòu)的設(shè)計(jì) 工作級(jí)別為M6。其中利用等級(jí)為T(mén)4,載荷狀況L2 3 吊鉤組的選擇計(jì)算 機(jī)構(gòu)工作級(jí)別:M6, 采用雙聯(lián)滑輪組,倍率: m=4起升質(zhì)量: = 18 t 起升載荷: 起升速度: ~ 初取 吊鉤采用倍率m=4的雙聯(lián)滑輪組,故采用長(zhǎng)形吊鉤組吊鉤用普通的短吊鉤 選用吊鉤斷面為梯形的吊鉤,材料為20鋼,機(jī)加工前熱處理,硬度小于或等于156HBS 單鉤 D 即D= mm 則由公式 得，h=150 (因?yàn)榈蹉^斷面為梯形，故h=D)Q額 ：額定起重量（噸） 1—2和3—4斷面為危險(xiǎn)斷面，通常垂直斷面3—4取與水平斷面1—2相同的斷面，而最大拉應(yīng)力約為1—2斷面的50% ，故只驗(yàn)算1—2面。一個(gè)工作循環(huán)一般包括上料、運(yùn)送、卸料及回到原位的過(guò)程，即取物裝置從取物地點(diǎn)由起升機(jī)構(gòu)把物料提起，由運(yùn)行機(jī)構(gòu)把物料移位，然后物料在指定地點(diǎn)下放，接著進(jìn)行相反動(dòng)作，使取物裝置回到原處，以便進(jìn)行下一次工作循環(huán)。 小車(chē) 小車(chē)由起升機(jī)構(gòu)，小車(chē)運(yùn)行機(jī)構(gòu)，小車(chē)架和保護(hù)裝置等組成。它通常用來(lái)搬運(yùn)物品，也可用于設(shè)備的安裝與檢修等用途。在起重機(jī)控制方面，起升機(jī)構(gòu)用主令控制器和磁力控制屏來(lái)實(shí)現(xiàn)控制，大、小車(chē)運(yùn)行機(jī)構(gòu)用凸輪控制器直接控制。指導(dǎo)教師： 2010年 6 月 5 日答辯簡(jiǎn)要情況及評(píng)語(yǔ)答辯小組： 年 月 日答辯委員會(huì)意見(jiàn)答辯委員會(huì)主任： 年 月 日目錄中文摘要 ……………………………………………………………………… Ⅰ英文摘要 ……………………………………………………………………… Ⅰ1緒論 …………………………………………………………………………… 1 ………………………………………………………… 1 ……………………………………… 1 ………………………………………………………………… 1 ………………………………………………………………… 1 ……………………………………………… 1 …………………………………………… 12設(shè)計(jì)任務(wù)及參數(shù) ……………………………………………………………… 2 …………………………………………………………… 2 ………………………………………………… 23吊鉤組的設(shè)計(jì)計(jì)算 …………………………………………………………… 2 ………………………………………………………………… 2 ………………………………………………………………… 24滑輪組的設(shè)計(jì)計(jì)算 …………………………………………………………… 65鋼絲繩的選擇 ……………………………………………………………… 86卷筒的設(shè)計(jì)計(jì)算……………………………………………………………… 97鋼絲繩在卷筒上的固定……………………………………………………… 118起升機(jī)構(gòu)的設(shè)計(jì)計(jì)算………………………………………………………… 12 ……………………………………………………………… 12…………………………………………………………… 129小車(chē)運(yùn)行機(jī)構(gòu)的設(shè)計(jì)計(jì)算…………………………………………