1、河北聯(lián)合高校輕工學(xué)院qinggong college, hebei united university英文翻譯同學(xué)姓名：聶志峰學(xué)號(hào)：200715150401專業(yè)班級(jí)： 07 機(jī)械 4 班學(xué)部：工程訓(xùn)練部指導(dǎo)老師： 程秀芳教授2021 年 6 月 12 日第一章緒論1.1 本課題討論的主要意義機(jī)械故障診斷技術(shù)是近 40 年來(lái)進(jìn)展起來(lái)的識(shí)別機(jī)器或機(jī)組運(yùn)行狀態(tài)的科學(xué)；它是適應(yīng)工程實(shí)際需要而形成的多學(xué)科交叉的綜合學(xué)科；它討論的是機(jī)器或機(jī)組運(yùn)行狀 態(tài)的變化在診斷信息中的反映， 它是由機(jī)器運(yùn)行中的物理現(xiàn)象 （聲音、振動(dòng)、聲發(fā)射、熱現(xiàn)象等）動(dòng)身來(lái)推斷機(jī)器內(nèi)含故障的技術(shù)，是一種典型的反向工程；從20 世紀(jì) 6

2、0 歲月開(kāi)頭，機(jī)械故障診斷技術(shù)隨著機(jī)器的不斷完善、復(fù)雜化和自動(dòng)化組建進(jìn)展起來(lái)，并與當(dāng)代科技的前沿科學(xué)結(jié)合，取得了令人矚目的成果；滾動(dòng)軸承是各種旋轉(zhuǎn)機(jī)械中應(yīng)用最廣泛的一種通用部件，也是機(jī)械設(shè)備中的易損零件， 很多機(jī)械的故障都與滾動(dòng)軸承的狀態(tài)有關(guān)； 據(jù)統(tǒng)計(jì)， 在使用滾動(dòng)軸承的旋轉(zhuǎn)機(jī)械中，大約 30的機(jī)械故障是由于滾動(dòng)軸承的損壞造成的；可見(jiàn)，滾動(dòng)軸承的好壞對(duì)機(jī)械系統(tǒng)工作狀況的影響極大； 由于設(shè)計(jì)不當(dāng)和安裝工藝不好或軸承的使用條件不佳，或突發(fā)載荷的影響， 使軸承運(yùn)轉(zhuǎn)一段時(shí)間后會(huì)產(chǎn)生各種各樣的缺陷，并且在連續(xù)運(yùn)行中進(jìn)一步擴(kuò)大， 使軸承運(yùn)行狀態(tài)發(fā)生變化； 因此， 滾動(dòng)軸承的故障診斷始終是討論的熱點(diǎn)；而與其

3、它零部件相比，滾動(dòng)軸承有一個(gè)很大的特點(diǎn)，這就是其壽命離散性很大；由于在材料、加工精度、熱處理及裝配質(zhì)量等各方面不行能完全相同， 使得一批類型、尺寸相同的軸承， 即使在相同條件下工作， 各個(gè)軸承的壽命也是不同的， 壽命最大相差可達(dá)幾十倍； 由于軸承的這個(gè)特點(diǎn)， 在實(shí)際使用中就顯現(xiàn)這種情形： 有的軸承已大大超過(guò)設(shè)計(jì)壽命卻依舊完好地工作；有的軸承遠(yuǎn)未達(dá)到設(shè)計(jì)壽命就顯現(xiàn)故障；所以，假如依據(jù)設(shè)計(jì)壽命對(duì)軸承進(jìn)行定時(shí)修理， 就顯現(xiàn)以下情形： 一方面，對(duì)超過(guò)設(shè)計(jì)壽命而完好工作的軸承拆下來(lái)作為報(bào)廢處理， 造成鋪張； 另一方面， 未達(dá)到設(shè)計(jì)壽命而顯現(xiàn)故障的軸承堅(jiān)持到定時(shí)修理時(shí)拆下來(lái)報(bào)廢，使得機(jī)械在軸承顯現(xiàn)故障后和

4、拆下來(lái)這 段時(shí)間內(nèi)工作精度下降， 未到修理時(shí)間就顯現(xiàn)故障， 導(dǎo)致整個(gè)機(jī)械顯現(xiàn)嚴(yán)峻事故； 由此看來(lái)，對(duì)重要用途的軸承來(lái)說(shuō)定時(shí)修理是很不科學(xué)的， 要進(jìn)行工況監(jiān)測(cè)與故障診斷， 改傳統(tǒng)的定期修理為預(yù)知性修理， 這樣既能常常保持設(shè)備的完好狀態(tài)， 又能充分利用軸承的使用壽命，從而延長(zhǎng)大修時(shí)間，縮短大修時(shí)間，削減故障停機(jī)缺失；因此，滾動(dòng)軸承的工況監(jiān)測(cè)與故障診斷引起國(guó)內(nèi)外很多科技人員的重視；1.2 滾動(dòng)軸承故障診斷方法滾動(dòng)軸承的工況監(jiān)測(cè)與故障診斷就是通過(guò)對(duì)滾動(dòng)軸承在各種工況下表現(xiàn)出來(lái)的- 5 -振動(dòng)、噪聲、溫度、工作參數(shù)、氣味、泄漏等信息的監(jiān)測(cè)和綜合分析來(lái)對(duì)其工作狀態(tài)、故障類型和故障嚴(yán)峻程度進(jìn)行綜合評(píng)判的過(guò)程

5、，主要包括檢測(cè)試驗(yàn)技術(shù)、 信號(hào)處理技術(shù)、模式識(shí)別技術(shù)和猜測(cè)評(píng)估技術(shù) 4 項(xiàng)基本技術(shù)， 從而實(shí)現(xiàn)檢測(cè)和發(fā)覺(jué)反常、 診斷故障狀態(tài)和部位、分析故障類型、提出診斷方案和診斷結(jié)論的目的；目前，依據(jù)故障監(jiān)測(cè)和診斷技術(shù)機(jī)理的不同， 滾動(dòng)軸承的故障診斷技術(shù)主要包括：1. 振動(dòng)信號(hào)監(jiān)測(cè)診斷技術(shù)在各種軸承故障診斷方法中， 振動(dòng)檢測(cè)是最常用的一種方法； 軸承元件的工作表面顯現(xiàn)疲憊剝落、 壓痕或局部腐蝕時(shí)， 軸承運(yùn)行中會(huì)顯現(xiàn)周期性的脈沖信號(hào)； 這種周期性信號(hào)可由安裝在軸承座上的傳感器 速度型或加速度型 來(lái)接收，通過(guò)對(duì)振動(dòng)信號(hào)的分析就可以實(shí)現(xiàn)對(duì)滾動(dòng)軸承運(yùn)行狀態(tài)的監(jiān)測(cè)與診斷；2. 噪聲信號(hào)監(jiān)測(cè)診斷技術(shù)這種方法是通過(guò)滾動(dòng)軸

6、承在運(yùn)行過(guò)程中的噪聲來(lái)判定其故障；用噪聲法進(jìn)行軸承的故障檢測(cè)， 優(yōu)點(diǎn)是不必接觸受測(cè)軸承就可得到檢測(cè)信號(hào)； 其弊端就是很難從四周環(huán)境的各種雜音中分別出軸承反常的聲音信號(hào)；所以，噪聲法一般很少被采納； 但勝利的例子也是有的， 就是在方向性強(qiáng)的拋物線型音響器上安裝傳聲器，收集軸承發(fā)出的聲音信號(hào)，并用反向?yàn)V波器排除其它雜音，檢測(cè)出軸承異音；3. 溫度信號(hào)監(jiān)測(cè)診斷技術(shù)通過(guò)安裝在軸承座 或箱體 處的溫度傳感器監(jiān)測(cè)溫度，判定軸承工作是否正常；溫度監(jiān)測(cè)對(duì)軸承載荷、 速度和潤(rùn)滑情形的變化反映比較敏銳，特別是對(duì)潤(rùn)滑不良而引起的軸承過(guò)熱現(xiàn)象很敏銳；所以，由于這種場(chǎng)合比較有效；但是，當(dāng)軸承顯現(xiàn)諸如早 期點(diǎn)蝕、剝落、稍

7、微磨損等比較微小的故障時(shí)，溫度監(jiān)測(cè)基本上沒(méi)有反映，只是當(dāng)故 障達(dá)到肯定的嚴(yán)峻程度時(shí)，用這種方法才能監(jiān)測(cè)到；所以，溫度監(jiān)測(cè)不適用于點(diǎn)蝕、 局部剝落等所謂的局部損耗類故障；4. 油樣分析監(jiān)測(cè)診斷技術(shù)油樣分析法油樣分析法有光譜分析與鐵譜分析兩大類；軸承磨損顆粒與其工作狀況有親密的聯(lián)系； 光譜分析方法有多種， 但共同點(diǎn)是利用光譜分析， 測(cè)定油液中所含各種金屬元素的成分和含量， 以判定含有被測(cè)元素的零部件的磨損狀況和程度；鐵譜分析方法是將帶有磨損顆粒的潤(rùn)滑油通過(guò)一強(qiáng)磁場(chǎng)，在強(qiáng)磁場(chǎng)的作用下， 磨粒按肯定的規(guī)律沉淀在鐵譜片上，鐵譜片可在鐵譜顯微鏡上做定性觀看或在定量?jī)x器上測(cè)試，據(jù)此判定軸承的工作狀況；油樣分

8、析法適合于用潤(rùn)滑油潤(rùn)滑的軸承的故障診斷，對(duì)使用脂潤(rùn)滑的軸承較困難；另外，這種方法易受其它非軸承損壞掉下的顆粒的影響；多用于離線監(jiān)測(cè)方式，這樣會(huì)導(dǎo)致肯定信息丟失； 信息量大且雜， 即有圖像又有數(shù)字， 依靠人力來(lái)治理是特別困難的；所以，這種方法具有很大的局限性；5. 油膜電阻監(jiān)測(cè)診斷技術(shù)潤(rùn)滑良好的軸承，由于油膜的作用，內(nèi)、外圈之間有很大的電阻；故通過(guò)測(cè)量軸 承內(nèi)、外圈之間的電阻， 可對(duì)軸承的反常作出判定； 其特點(diǎn)是對(duì)不同的工況條件可使用同一評(píng)判標(biāo)準(zhǔn)，適用于旋轉(zhuǎn)軸外露的場(chǎng)合，對(duì)表面剝落、壓痕、裂紋等反常的診斷 成效比較差；隨著科學(xué)技術(shù)的不斷進(jìn)展， 一些新的監(jiān)測(cè)技術(shù)不斷顯現(xiàn)并應(yīng)用于滾動(dòng)軸承的工況監(jiān)測(cè)與

9、診斷中，例如：聲發(fā)射技術(shù)、光纖技術(shù)等；但是由于種種緣由和局限性，這些技術(shù)真正普及應(yīng)用于實(shí)際的滾動(dòng)軸承故障診斷仍有一段距離；1.3 滾動(dòng)軸承故障診斷技術(shù)的進(jìn)展概況滾動(dòng)軸承的故障診斷技術(shù)大致開(kāi)頭于20 世紀(jì) 60 歲月；最原始的軸承故障診斷方法是將聽(tīng)音棒接觸軸承部位， 依靠聽(tīng)覺(jué)來(lái)判定有無(wú)故障； 后來(lái)逐步采納各式測(cè)振儀器、外表并利用振動(dòng)位移、 速度或加速度的均方根值來(lái)判定軸承有無(wú)故障；隨著對(duì)滾動(dòng)軸承的運(yùn)動(dòng)學(xué)、 動(dòng)力學(xué)的深化討論， 對(duì)于軸承振動(dòng)信號(hào)中頻率成分和軸承零件的幾何尺寸及缺陷類型的關(guān)系有了比較清晰的明白，加之快速傅立葉變換fft 技術(shù)的進(jìn)展， 開(kāi)創(chuàng)了用頻域分析法來(lái)檢測(cè)和診斷軸承故障的有效途徑；

10、在幾十年的進(jìn)展時(shí)間里， 各種方法與技巧不斷產(chǎn)生、 進(jìn)展和完善， 應(yīng)用的領(lǐng)域不斷擴(kuò)大， 診斷的有效性不斷提高 . 總的來(lái)說(shuō)，滾動(dòng)軸承故障診斷的進(jìn)展經(jīng)受了以下幾個(gè)階段：第一階段：利用低頻信號(hào)接收法診斷階段20 世紀(jì) 60 歲月中期，由于快速傅立葉變換fft 技術(shù)的顯現(xiàn) 1965 年 和進(jìn)展， 低頻信號(hào)接收法得到了很大的進(jìn)展； 低頻信號(hào)接收法是將軸承上由傳感器檢測(cè)到的寬頻信號(hào)直接進(jìn)行頻譜分析，或者信號(hào)經(jīng)過(guò)低通濾波，去除高頻成分后在作頻譜分析， 從頻譜上觀看主要譜峰； 假如某一譜峰對(duì)應(yīng)的頻率與理論運(yùn)算軸承元件的間隔頻率相一樣， 就表示該元件上存在故障； 這種方法對(duì)于低頻成分能量較大，外來(lái)干擾較小的信號(hào)

11、，理論上說(shuō)應(yīng)當(dāng)是可行的，但實(shí)際運(yùn)行中的軸承，由于故障沖擊的能量很小，而 軸承、齒輪的工藝誤差誘發(fā)的振動(dòng)能量比它要大得多；因此， 直接利用低頻信號(hào)接收法得到的譜圖往往譜線密集， 模糊不清， 很難鑒別出故障信號(hào)； 目前很少直接用這種方法去識(shí)別軸承故障，有些僅是用這種頻譜來(lái)確定軸承元件的固有頻率；其次階段：利用沖擊脈沖法診斷階段在 60 歲月末期，第一由瑞典spm儀器公司開(kāi)發(fā)出沖擊脈沖計(jì)，依據(jù)沖擊脈沖的最大幅值來(lái)診斷軸承故障； 滾動(dòng)軸承在運(yùn)轉(zhuǎn)中， 假如滾動(dòng)體接觸點(diǎn)進(jìn)入表面缺陷區(qū) （剝落、裂紋、凹坑和高低不平的粗糙區(qū)） ，就將發(fā)生低頻沖擊，并且以不連續(xù)的沖擊脈沖波形式傳遞到軸承座上； 雖然沖擊脈沖波形

12、很快被衰減下去，累積的能量很小； 然而，在這個(gè)沖擊力作用下，軸承元件或結(jié)構(gòu)的某一部分可能被激發(fā)起它的固有頻率；盡管沖擊脈沖的重復(fù)頻率遠(yuǎn)低于軸承的固有頻率， 但只要這個(gè)沖擊產(chǎn)生的高階頻率落在軸承固有頻率的通帶內(nèi)， 也會(huì)激起軸承系統(tǒng)的共振現(xiàn)象； 共振的高頻波中包含了低頻沖擊和隨機(jī)干擾的幅值調(diào)制波， 經(jīng)過(guò)窄帶濾波和包絡(luò)檢波后的信號(hào)幅值大小就反映了沖擊力的大小，也就反應(yīng)了滾動(dòng)軸承工作表面的故障狀況；第三階段：利用共振解調(diào)法診斷階段共振解調(diào)法也稱為包絡(luò)檢波頻譜分析法；1974 年，美國(guó)波音公司的 dr harting 創(chuàng)造了一項(xiàng)叫做“共振解調(diào)分析系統(tǒng)”的專利，這就是我國(guó)現(xiàn)在統(tǒng)稱的“共振解調(diào)技 術(shù)”的雛形

13、；共振解調(diào)法與沖擊脈沖法的基本原理類似，但能做到更精確的診斷；沖擊脈沖法只能給出軸承損耗程度的指標(biāo)， 一般來(lái)說(shuō)并不能判定軸承的損耗部位；而共振解調(diào)法不僅能判定軸承的損耗程度，仍可以通過(guò)頻譜分析指示出軸承的損耗部位； 共振解調(diào)法也是利用軸承或檢波系統(tǒng)作為諧振體， 把故障沖擊產(chǎn)生的高頻共振響應(yīng)波放大，通過(guò)包絡(luò)檢測(cè)方法變?yōu)榫哂泄收咸攸c(diǎn)信息的低頻波形，然后采納頻譜分析法找出故障的特點(diǎn)頻率（間隔頻率） ，從而確定故障的類型以及故障發(fā)生在軸承的哪一元件上；共振解調(diào)法適用于軸承故障的早期診斷； 由于早期故障特別稍微， 它引起的沖擊脈沖強(qiáng)度特別小， 所以其振動(dòng)響應(yīng)信號(hào)的故障特點(diǎn)很不明顯， 用一般方法很難辨別出

14、來(lái)；采納共振解調(diào)技術(shù)由于放大 諧振 和分別 帶通濾波 了故障特點(diǎn)信號(hào)， 極大地提高了信噪比，所以能比較簡(jiǎn)單地診斷出故障來(lái)；第四階段：開(kāi)發(fā)以微機(jī)為中心的滾動(dòng)軸承故障診斷系統(tǒng)階段20 世紀(jì) 90 歲月以來(lái)，隨著微機(jī)技術(shù)迅猛進(jìn)展，開(kāi)發(fā)以微機(jī)為中心的滾動(dòng)軸承故障診斷系統(tǒng)引起了國(guó)內(nèi)外討論者的重視； 微機(jī)信號(hào)分析和故障診斷系統(tǒng)不但具有敏捷性高，適應(yīng)性強(qiáng)，易于保護(hù)和升級(jí)的特點(diǎn)，而且易于推廣和應(yīng)用；1.4 滾動(dòng)軸承故障診斷技術(shù)的進(jìn)展方向近些年， 故障診斷的新技術(shù)和新方法層出不窮，人工智能和運(yùn)算機(jī)在軸承故障診斷中的應(yīng)用越來(lái)越廣泛，今后的進(jìn)展方向主要表達(dá)在以下方面：1. 時(shí)域分析和頻譜分析在軸承故障診斷中的應(yīng)用將

15、日趨完善；2. 對(duì)于軸承故障診斷的理論和方法進(jìn)一步深化討論，并且各種討論成果將會(huì)逐步應(yīng)用到實(shí)際生產(chǎn)；3. 故障診斷智能系統(tǒng)進(jìn)一步的深化討論，多種軸承故障分析方法相結(jié)合，如小波神經(jīng)網(wǎng)絡(luò)、 模糊識(shí)別與小波分析相結(jié)合等新分析方法應(yīng)用智能專家系統(tǒng)，提高診斷的效率和精確率；4. 隨著運(yùn)算機(jī)和網(wǎng)絡(luò)技術(shù)的進(jìn)展，遠(yuǎn)程故障診斷將是現(xiàn)代故障診斷進(jìn)展的一個(gè)重要的方向；1.5 本課題主要討論內(nèi)容本文分析討論了滾動(dòng)軸承的常見(jiàn)失效形式及其特點(diǎn)，總結(jié)滾動(dòng)軸承的振動(dòng)機(jī)理和振動(dòng)信號(hào)特點(diǎn)， 討論了滾動(dòng)軸承信號(hào)處理及故障診斷的方法， 搭建了滾動(dòng)軸承故障診斷系統(tǒng)，采納較為先進(jìn)、成熟的故障診斷方法，對(duì)滾動(dòng)軸承進(jìn)行故障診斷；本文的主 要

16、內(nèi)容如下 :第一章：緒論；簡(jiǎn)要介紹了本課題討論的意義、滾動(dòng)軸承故障診斷方法、滾動(dòng)軸承故障診斷技術(shù)進(jìn)展概況、進(jìn)展方向；其次章： 滾動(dòng)軸承的故障特點(diǎn)分析； 分析滾動(dòng)軸承的主要失效形式和緣由， 分析運(yùn)算滾動(dòng)軸承的理論特點(diǎn)頻率和固有振動(dòng)頻率，討論滾動(dòng)軸承的故障信號(hào)特點(diǎn)；第三章：滾動(dòng)軸承故障診斷方法討論；包括時(shí)域方法、頻域方法，對(duì)各種方法的特點(diǎn)進(jìn)行了比較；第四章： 滾動(dòng)軸承故障診斷系統(tǒng)總體設(shè)計(jì)； 在滾動(dòng)軸承故障診斷方法理論的基礎(chǔ)上搭建基于 matlab 的滾動(dòng)軸承故障診斷系統(tǒng)，對(duì)軟件系統(tǒng)進(jìn)行總體設(shè)計(jì)；第五章： 滾動(dòng)軸承實(shí)測(cè)信號(hào)分析； 通過(guò)對(duì)采集的滾動(dòng)軸承實(shí)測(cè)信號(hào)分析， 驗(yàn)證各種診斷方法的優(yōu)劣和滾動(dòng)軸承的

17、故障特點(diǎn)；其次章滾動(dòng)軸承的故障特點(diǎn)分析2.1 概述滾動(dòng)軸承是旋轉(zhuǎn)機(jī)械中的重要零件，它在各個(gè)機(jī)械部門(mén)中的應(yīng)用最為廣泛； 它的運(yùn)行質(zhì)量直接影響整臺(tái)設(shè)備的工作性能（包括精度，牢靠性，壽命等）；一般來(lái)說(shuō)對(duì)滾動(dòng)軸承采納以設(shè)計(jì)壽命為限的定時(shí)進(jìn)行修理；但是，如前文所述這種修理制度會(huì)對(duì)設(shè)備的連續(xù)運(yùn)行帶來(lái)肯定的影響；一方面，對(duì)超過(guò)設(shè)計(jì)壽命而運(yùn)行完好的滾動(dòng)軸承拆下來(lái)作報(bào)廢處理，造成鋪張； 另一方面， 已處于失效狀態(tài)的軸承連續(xù)使用會(huì)造成整機(jī)運(yùn)行性能的下降， 甚至?xí)劤蓢?yán)峻的事故； 因此必需加強(qiáng)滾動(dòng)軸承的監(jiān)測(cè)工作， 改傳統(tǒng)的定期修理為預(yù)知性修理， 最大限度地發(fā)揮軸承的工作潛力，提高設(shè)備的運(yùn)行效率；2.2 滾動(dòng)軸承的典

18、型結(jié)構(gòu)滾動(dòng)軸承是有內(nèi)圈、外圈、滾動(dòng)體和保持架等元件組成；內(nèi)圈、外圈分別與 軸頸及軸承座孔裝備在一起； 在大多數(shù)情形下外圈不動(dòng)， 而內(nèi)圈隨軸回轉(zhuǎn)； 滾動(dòng)體是滾動(dòng)軸承的核心元件， 它使相對(duì)運(yùn)動(dòng)表面間的滑動(dòng)摩擦變?yōu)闈L動(dòng)摩擦；滾動(dòng)體的形式有球形、 圓形、錐柱形和鼓形等； 滾動(dòng)體可在內(nèi)、 外圈滾道上進(jìn)行滾動(dòng)；2.3 滾動(dòng)軸承的主要失效形式及緣由由于滾動(dòng)軸承的材料缺陷，加工或裝配不當(dāng)，潤(rùn)滑不良，水份和異物侵入， 腐蝕以及過(guò)載等緣由都可能導(dǎo)致早期損壞； 當(dāng)然， 即使在安裝、 潤(rùn)滑和使用保護(hù)都正常的情形下， 經(jīng)過(guò)一段時(shí)間的運(yùn)轉(zhuǎn)， 軸承也會(huì)顯現(xiàn)疲憊剝落和磨損等現(xiàn)象影響機(jī)器的正常工作；概括起來(lái)滾動(dòng)軸承的主要故障形

19、式有:1. 塑性變形- 23 -軸承轉(zhuǎn)速 n1 r min時(shí)，其損壞形式主要失效形式是塑性變形，這與接觸表面的最大擠壓應(yīng)力有關(guān)（如工作負(fù)荷過(guò)重，熱變形影響，過(guò)大的沖擊載荷等）；按彈性理論分析， 接觸表面的最大擠壓應(yīng)力發(fā)生在受力最大的一個(gè)滾動(dòng)體與軸承內(nèi)圈的接觸點(diǎn)處，其損壞的特點(diǎn)是滾道上形成一個(gè)個(gè)小圓穴（凹痕），使軸承在運(yùn)轉(zhuǎn)時(shí)產(chǎn)生很大的振動(dòng)和噪聲；2. 疲憊剝落滾動(dòng)體在滾道上由于反復(fù)承擔(dān)載荷， 工作到肯定時(shí)間后， 第一在接觸表面一定深度處形成裂紋（該處的切應(yīng)力最大） ，然后逐步進(jìn)展到接觸表面，使表層金屬呈片狀剝落下來(lái)， 形成剝落凹坑， 即形成疲憊剝落； 疲憊剝落使軸承在工作時(shí)發(fā)生沖擊性振動(dòng)；在正常

20、工作條件下，疲憊剝落是軸承的主要失效形式；3. 磨損或擦傷滾動(dòng)體與滾道之間的相對(duì)運(yùn)動(dòng)以及外界污物的侵入，是軸承工作表面產(chǎn)生磨損的直接緣由；潤(rùn)滑不良，裝配不正確均會(huì)加劇磨損或擦傷；磨損量較大時(shí)，軸 承游隙增大， 不僅降低了軸承的運(yùn)轉(zhuǎn)精度， 也會(huì)帶來(lái)機(jī)器的振動(dòng)和噪聲， 對(duì)精密機(jī)械用的軸承，磨損量就成為打算軸承使用壽命的主要因素；4. 銹蝕和電蝕銹蝕是由于空氣中或外界的水分帶入軸承中，或者機(jī)器在腐蝕性介質(zhì)中工 作，軸承密封不嚴(yán)， 從而引起化學(xué)腐蝕； 銹蝕產(chǎn)生的銹斑使軸承工作表面產(chǎn)生早期剝落，而端面生銹就會(huì)引起保持架磨損； 電蝕主要是轉(zhuǎn)子帶電， 在肯定條件下， 電流擊穿油膜產(chǎn)生電火花放電，使軸承工作表

21、面形成密集的電流凹坑；5. 斷裂軸承零件的裂紋和斷裂是最危急的一種失效形式， 這主要是由于軸承超負(fù)荷運(yùn)行、金屬材料有缺陷和熱處理不良引起的；轉(zhuǎn)速越高，潤(rùn)滑不良，軸承在軸上 壓配過(guò)盈量太大以及過(guò)大的熱應(yīng)力會(huì)引起裂紋和斷裂；6. 膠合膠合指滾道和滾動(dòng)體表面由于受熱而局部融合在一起的現(xiàn)象；常發(fā)生在潤(rùn)滑不良、高速、重載、高溫、起動(dòng)加速度過(guò)大等情形下；由于摩擦發(fā)熱，軸承零件 可以在極短時(shí)間內(nèi)達(dá)到很高的溫度， 導(dǎo)致表面灼傷， 或某處表面上的金屬粘附到另一表面上；7. 保持架損壞通常，由于裝配或使用不當(dāng)而引起保持架發(fā)生變形， 從而就可能增加保持架與滾動(dòng)體之間的摩擦， 甚至使某些滾動(dòng)體卡死而不能滾動(dòng)， 或者由

22、于保持架與內(nèi)外滾道發(fā)生摩擦等均可能引發(fā)保持架損壞，導(dǎo)致振動(dòng)、噪聲與發(fā)熱增加；chapter iintroduction1.1 the main significance of this researchmachinery faultdiagnosis technology has developed to identifyscientific machine or running state in nearly 40 years. it is to adapt to the need of the actual engineering and the formation of interdis

23、ciplinary comprehensive discipline. what it studies is the machine or the unit running status change in the diagnostic message reflection. it is the technology by the machine run inphysical phenomenon sound, vibration, sound launch, hot phenomenon and so on embarks infers the machine content breakdo

24、wn and is one kind of typicalreverse engineering. started from the 1960s, along with the machine consummates,the complication and the automation unceasingly the mechanical fault diagnosis technology has developed, and with the contemporary science's and technology's front science union, has

25、made the amazing progress.the rollingbearing is one kind of general part in each kind of revolving machinery applies. rolling element bearing is one of the most widely used general part of rotating machinery,and one of the most easily damagedparts of mechanical equipment. a lot of mechanical failure

26、 is relevant to the state of rollingelement bearings. it is estimated that about 30 percent of mechanical failure is caused by its fault in the rotating machine with rolling element bearings. it is obvious that the quality of rolling element bearings has a great impact on the working condition of el

27、ectromechanical systems. because of wrong design, poor working condition or a jump heavy load, bearing will be damaged and worse during the running time. so at present, the fault diagnosis of rolling element bearings is a research hotspot.but compares with other spare parts, the rollingbearing has a

28、 very majorcharacteristic, this is its life leaves the divergence to be very big. because in the material, the working accuracy, the heat treatment and the assembly quality and so on various aspects is impossible identical, causes one batch of types, the size same bearing, even if works under the sa

29、me condition, life is different for each bearing, and difference up dozens of times. as a result of bearing's this characteristic, it has thiskind of situation in the actual use: some bearings have significantly exceeded design life and work is still intact; some bearings have not achieved the d

30、esign life to present the breakdown. therefore, if carries on according to the design life to the bearing fixed time services, then has the following situation: on the one hand, the bearing surpasses the design life,but works complete the bearing opens downtakes abandonmentprocessing, creates the wa

31、ste; on the other hand, the bearing has not achieved the design life to present the breakdown to insist fixed time services when dismantles the incoming telegram to be waste, causes the machinery after the bearing presents the breakdown and opens down in this period of time to work the precision to

32、drop, has not presented the breakdown to the maintenance time, causesthe entire machinery to present the serious accident. therefore, to the important use's bearing settled when the service is very unscientific, must carry on the operating mode monitor and the failure diagnosis, changes traditio

33、nal the regular service is the forecasting service, likethisbothcan maintainequipment's sound condition frequently, and can use bearing's service life fully, thus the extension overhaul time, reduces the overhaul time, reduces the disaster dump to lose. therefore, rolling bearing's opera

34、ting mode monitor and the failure diagnosis bring to the domestic and foreign many technical personnel's attention.1.2 rolling bearing failure diagnosis methodrolling bearing's operating mode monitor and the failure diagnosis are through to the rollingbearing information and so on vibration

35、which, noise, temperature, operational parameter, smell, divulging displays under each kind of operating mode monitors and the generalized analysis to its active status, the breakdown type and the breakdown order of severity carry on the quality synthetic evaluation the process, mainlyincludes the e

36、xamination experiment technology, the signal processingtechnology, the pattern recognition technology and the forecast appraisal technology 4 basic strokes, thus realizes the examination and the discovery exceptionally, the diagnosis malfunction and the spot, the analysis breakdown type, proposes th

37、e diagnosis plan and the diagnosis conclusion goal.at present, according to the breakdown monitor and the diagnosis technology mechanism's difference, rolling bearing's failure diagnosis technology mainly includes:1. vibration signal monitor diagnosis technologyin each bearing failure diagno

38、sis method, the vibration examination is the most commonly used one method. when the bearing part's active face presents weary flaking, the indentation or the localized corrosion, in the bearing movement will present the periodic signal impulse. this kind of periodic signal may by install the se

39、nsor speed or acceleration receives on the bearing seat, through to vibrates the signal the analysis to be possible to realize to the roll axis undertakes to transport the row state the monitor and the diagnosis.2. noise signal monitor diagnosis technologythis method is judges its breakdown through

40、rollingbearing's in movement process noise. carries on bearing's failure detection with the noise law, the merit does not need to contact was measured that the bearing may obtain the detection signal; its malpractice is separates the bearing unusual sound signal very difficultlyfrom environm

41、ent each kind of static. therefore, the noise laws are very generally few are used. but the successexample also has, is installs the microphone on the directive strong parabola sounder, collects sound signal which the bearing sends out, and removes other static with the reverse filter, examines the

42、bearing different sound.3. temperature signal monitor diagnosis technologythrough installs in the bearing seat or box body place temperature sensor monitor temperature, judges the bearing to work whether normally. the temperature monitoring to the bearing load, the speed and the lubrication situatio

43、n's change reflection is quite sensitive, particularly the bearing overheated phenomenon which causes to the insufficient lubrication is very sensitive. therefore, because this kind of situation is quite effective. but, when the bearing presents such as the early pitting, flaking,the slight attr

44、itionand so on quite small breakdown, the temperature monitoring basically had not reflected that is only when the breakdown achieves certain order of severity, can monitor with this method. therefore, the temperaturemonitoring is not suitable for the pitting, partial flaking and so on so-called par

45、tial damage class breakdown.4. oil type analysis monitor diagnosis technologythe oil type analytic method oil type analytic method has the spectral analysis and the hard spectrum analyzes two broad headings. the bearing attrition pellet has close contacting with its working condition. the spectral a

46、nalysis method has many kinds, but the common ground uses the spectral analysis, determines in the fat liquor to contain each metallicelement ingredient and the content, judges includes is measured the element the spare part wear conditionand the degree. the hard spectrum analysis method has the att

47、rition pellet lubricating oil through a strong magnetic field, under the strong magnetic field's function, the abrasive precipitates according to certain rule on the hard spectrum piece, the hard spectrum piece may make the qualitative observation or on the hard spectrum microscope tests on the

48、quota instrument, according to the above judges bearing's working condition.the oiltype analytic method suits in using the lubricationoillubrication bearing's failure diagnosis, for uses the bearing which the fat lubricates to be difficult. moreover, this method easily the pellet influence w

49、hich falls down other non-bearing failure; uses in the off-line monitor way, like this will cause certain bit drop-out; the information content is big and is mixed, namely has the image also to have the digit, depends upon the manpower to manage is very difficult. therefore, this method has the very

50、 big limitation.5. lubricant film resistance monitor diagnosis technologythe bearing has the good lubricates, as a result of the lubricant film function, between the addendum circle has the very big resistance. therefore through surveys between the bearings, the addendum circle resistance may except

51、ionally make the judgment to the bearing. its characteristic is may use the identical judgment standard to the differentoperating mode condition,is suitable situation whichappears externally in the rotation axis, to the surface scaling, the indentation, the crack and so on unusual diagnosis effect i

52、s quite bad.alongwithscience's and technology's unceasing development, some newmonitor technology appears unceasingly and applies in rolling bearing's operating mode monitor and the diagnosis, for example: sound launch technology, optical fiber technology and so on. but with the limitati

53、on,this technical true popularization applies for various reasons in the actual rolling bearing failure diagnosis also has section of distances.1.3 rolling bearing failure diagnosis technology development surveyrolling bearing's failure diagnosis technology started probably in the 1960s. the mos

54、t primitive bearing failure diagnosis method is listens the stick contact bearing portion, whether there is depends upon the sense of hearing to judge the breakdown. afterward used various types vibration meter gradually, the measuring appliance and using the vibrationdisplacement, whether there is

55、the speed or the acceleration root-mean-square value judges the bearing breakdown. along with to rolling bearing's kinematics, the dynamics deep research, vibrated the signal medium frequency ingredient and the bearing part geometry size and the flaw type relations regarding the bearing had the

56、quite clear understanding, in addition the fast fournier transformation ffttechnology's development, founded examined and the diagnosis bearing breakdown efficient path with the frequency range analytic method. in several dozens year development time, each method and the skill have, the developm

57、ent and the consummation unceasingly, the application domain expand unceasingly, the diagnosis validityenhances unceasingly. generallyspeaking, the rollingbearing failure diagnosis's development has experienced the following several stages:the first stage: uses the low-frequency signal reception

58、 diagnosis stagein the mid-1960s, becausethe fast fournier transformation fft technology's appearance in1965 and the development, the low-frequencysignal reception obtained the very bigdevelopment. the low-frequencysignal reception is the broadband signal which examines from the sensor carries on directly the bearing on thespectralanalysis,orsignalafterlow-passfiltering,afterelimination high-frequency component, inmakes the spectral analysis, observes the main spectrum peak from the frequency spectrum. if some spe