韓國(guó)斗山大宇柴油發(fā)動(dòng)機(jī)廢氣渦輪增壓器的正確使用及故障診斷 (廢氣渦輪;增壓器;故障診斷)
　　韓國(guó)斗山大宇針對(duì)影響增壓器的使用壽命因素，故障和診斷加以分析，并說(shuō)明使用中的注意事項(xiàng)，意在減少增壓器的故障，延長(zhǎng)其使用壽命，降低維護(hù)費(fèi)用。

1 韓國(guó)斗山大宇廢氣渦輪增壓器的基本知識(shí)及工作原理

　　渦輪增壓器是用來(lái)提高發(fā)動(dòng)機(jī)功率和減少排放的重要部件。渦輪增壓器本身不是一種動(dòng)力源，它利用發(fā)動(dòng)機(jī)排氣中的剩余能量來(lái)工作，其作用是向發(fā)動(dòng)機(jī)提供更多的壓縮空氣。它利用發(fā)動(dòng)機(jī)排出的廢氣能量，驅(qū)動(dòng)渦輪高速旋轉(zhuǎn)，帶動(dòng)與渦輪同軸的壓氣機(jī)葉輪高速旋轉(zhuǎn)，壓力機(jī)將空氣壓縮進(jìn)入發(fā)動(dòng)機(jī)氣缸，增加了發(fā)動(dòng)機(jī)的充氣量，可供更多的燃油完全燃燒，從而提高了發(fā)動(dòng)機(jī)的功率，降低了燃油的消耗，同時(shí)由于燃燒條件的改善，減少了廢氣中有害物質(zhì)的排放，還可降低噪音。

　　柴油機(jī)經(jīng)過(guò)增壓以后性能發(fā)生了變化，它使柴油機(jī)的功率大大得到提高，增壓后發(fā)動(dòng)機(jī)的功率可提高20%～40%左右，以WD615機(jī)為例，使發(fā)動(dòng)機(jī)的機(jī)械效率提高，增壓后發(fā)動(dòng)機(jī)的輔助系統(tǒng)消耗的功增加很少，雖然因?yàn)楸l(fā)壓力大，各摩擦表面上的摩擦損失有所增加，但發(fā)動(dòng)機(jī)功率增加較多，機(jī)械效率提高了近8%左右。燃油消耗降低，增壓后進(jìn)氣壓力增高，燃燒條件改善，機(jī)械效率提高，油耗降低，發(fā)動(dòng)機(jī)單位功率質(zhì)量大大降低，但發(fā)動(dòng)機(jī)經(jīng)增壓后也帶來(lái)了新的問(wèn)題，如：使發(fā)動(dòng)機(jī)的機(jī)械負(fù)荷增加，發(fā)動(dòng)機(jī)的熱負(fù)荷增加等等。

　　2 影響韓國(guó)斗山大宇增壓器使用壽命的因素

　　使用中我們發(fā)現(xiàn)，增壓器的損壞和磨損總是在柴油機(jī)及其附近出現(xiàn)故障之后發(fā)生，柴油機(jī)的許多不正常工況都會(huì)引起增壓器的損壞。增壓器出現(xiàn)故障，40%是由于潤(rùn)滑不良造成的，40%是由于外界雜物通過(guò)增壓器所造成的，20%是其它原因引起的。

　　2.1潤(rùn)滑油。潤(rùn)滑油用來(lái)潤(rùn)滑冷卻增壓器，但當(dāng)增壓器正常工作時(shí)，其轉(zhuǎn)軸轉(zhuǎn)速高達(dá)每分鐘幾萬(wàn)轉(zhuǎn)到十幾萬(wàn)轉(zhuǎn)，潤(rùn)滑油被打成泡沫狀，其冷卻和潤(rùn)滑性能下降，因此潤(rùn)滑系統(tǒng)必須保證能提供充足的潤(rùn)滑油。若當(dāng)600℃左右的高溫廢氣通過(guò)渦輪室時(shí)，軸承座得不到足夠的潤(rùn)滑和冷卻，潤(rùn)滑油將在其環(huán)形油道壁上結(jié)焦，逐漸堵塞油道。

　　潤(rùn)滑油如果不清潔，也會(huì)很快損壞增壓器內(nèi)部零件。如含有灰塵、泥狀沉淀物和金屬微粒的潤(rùn)滑油會(huì)迅速破壞各零件的配合間隙，刮傷和磨損軸承表面。這些都將會(huì)引起渦輪軸轉(zhuǎn)動(dòng)阻力增大和失掉平衡，使軸的轉(zhuǎn)速下降，導(dǎo)致柴油機(jī)的功率損失增大，且轉(zhuǎn)動(dòng)不平衡將很快導(dǎo)致增壓器零件的損壞。

　　如果潤(rùn)滑油的質(zhì)量等級(jí)老化，油中的各種添加劑不能滿(mǎn)足增壓柴油機(jī)大負(fù)荷工作的潤(rùn)滑要求，潤(rùn)滑油將會(huì)加速氧化變質(zhì)，也會(huì)加劇柴油機(jī)和增壓器零件的磨損。

　　柴油機(jī)的起動(dòng)、熄火的操作方法不正確也將嚴(yán)重影響增壓器的壽命。如果柴油機(jī)起動(dòng)后，就立即將轉(zhuǎn)速升得很高，潤(rùn)滑油不能及時(shí)到達(dá)增壓器軸承而加速磨損。柴油機(jī)熄火后，若不首先使增壓器冷卻降溫，而且突然熄火，停止向增壓器供給機(jī)油，會(huì)導(dǎo)致增壓器內(nèi)部零件過(guò)熱，軸承油道中的機(jī)油炭化阻塞油道，將有軸承被咬死的危險(xiǎn)。

　　密封環(huán)泄露引起的渦輪后部積炭，將使旋轉(zhuǎn)零件轉(zhuǎn)動(dòng)發(fā)澀，而損失功率。旋轉(zhuǎn)零件的不平衡是引起密封環(huán)泄露的一個(gè)重要原因。曲軸通氣孔或增壓器回油管堵塞或阻力過(guò)大，也能引起密封環(huán)泄露。

　　2.2韓國(guó)斗山大宇進(jìn)氣系統(tǒng)。增壓器工作的好壞也依賴(lài)于進(jìn)氣系統(tǒng)，只有供給充足、干凈的空氣才能保證增壓器長(zhǎng)期無(wú)故障工作，使壽命延長(zhǎng)。所以應(yīng)定期檢查所有進(jìn)氣管接頭和軟管的密封性，防止漏氣。如果壓氣機(jī)到柴油機(jī)進(jìn)氣管漏氣，充氣量減少，將導(dǎo)致柴油機(jī)冒黑煙。當(dāng)有較大顆粒的灰塵或沙子進(jìn)入壓氣機(jī)會(huì)立刻損壞增壓器。較小的顆粒也會(huì)使工作輪葉片彎曲或被割削，并使其失去平衡，引起軸承和密封環(huán)的磨損加劇。不平衡的旋轉(zhuǎn)件與軸承發(fā)生碰撞時(shí)，使軸承上的油道逐漸縮小，導(dǎo)致潤(rùn)滑不良。隨著軸承的磨損，配合間隙增大，使壓氣機(jī)或渦輪機(jī)的工作輪葉片打擊殼體，這種故障的信號(hào)是噪音比平常增大很多。

　　韓國(guó)斗山大宇進(jìn)氣系統(tǒng)的進(jìn)氣阻力應(yīng)很小，如果空氣濾清器堵塞，進(jìn)氣阻力增大，充氣量減少，增大功率損失，同時(shí)，壓氣機(jī)一側(cè)的密封環(huán)將會(huì)由于壓力差太大而泄露，引起潤(rùn)滑油消耗量過(guò)大，這種故障的標(biāo)志是在壓氣機(jī)工作輪葉片后面出現(xiàn)一層暗色的潤(rùn)滑油膜。

　　2.3排放的廢氣。廢氣中很小的顆粒進(jìn)入渦輪機(jī)，與顆粒進(jìn)入壓氣機(jī)后果一樣，將導(dǎo)致增壓器的損壞。

　　韓國(guó)斗山大宇柴油機(jī)燃油供油量過(guò)大，進(jìn)氣阻力大，會(huì)使燃燒室內(nèi)可燃混合氣過(guò)濃而引起廢氣過(guò)熱，造成渦輪機(jī)殼體和油道過(guò)熱，廢氣從排氣管到渦輪室的通道泄露會(huì)降低渦輪機(jī)渦輪的轉(zhuǎn)速，增加冒煙，也會(huì)使渦輪機(jī)殼體過(guò)熱。這些都會(huì)導(dǎo)致渦輪室內(nèi)積炭及渦輪葉片的腐蝕。

　　潤(rùn)滑油壓力過(guò)高，潤(rùn)滑油將通過(guò)密封環(huán)滲入渦輪機(jī)也會(huì)造成渦輪室積炭。

　　3 韓國(guó)斗山大宇廢氣渦輪增壓器使用注意事項(xiàng)

　　廢氣渦輪增壓器經(jīng)常處于高溫下工作，進(jìn)入廢氣渦輪端的溫度在600℃左右。增壓器轉(zhuǎn)子以每分鐘幾萬(wàn)轉(zhuǎn)到十幾萬(wàn)轉(zhuǎn)的高速旋轉(zhuǎn)，為了保證增壓器的正常工作，使用中應(yīng)注意以下幾點(diǎn)： (1)使用正確牌號(hào)的潤(rùn)滑油，并定期更換。對(duì)渦輪增壓柴油機(jī)至少應(yīng)使用CD級(jí)增壓機(jī)油。

　　(2)韓國(guó)斗山大宇發(fā)動(dòng)機(jī)發(fā)動(dòng)以后，特別是在冬季，發(fā)動(dòng)機(jī)點(diǎn)火后，應(yīng)怠速運(yùn)轉(zhuǎn)幾分鐘，千萬(wàn)不能轟油門(mén)，以防止損壞增壓器油封。

　　(3)韓國(guó)斗山大宇火前，發(fā)動(dòng)機(jī)也應(yīng)怠速運(yùn)轉(zhuǎn)幾分鐘，讓發(fā)動(dòng)機(jī)、增壓器轉(zhuǎn)子的轉(zhuǎn)速降下來(lái)以后再熄火，以防止猛轟油門(mén)，增壓器轉(zhuǎn)速很高，突然熄火，機(jī)油泵不打油，增壓器轉(zhuǎn)子仍在高速慣性運(yùn)轉(zhuǎn)，干磨損壞軸承。

　　(4)由于經(jīng)常處于高溫下運(yùn)轉(zhuǎn)，到增壓器的潤(rùn)滑油管線(xiàn)由于高溫，內(nèi)部機(jī)油容易有部分的結(jié)焦，這樣會(huì)造成增壓器軸承的潤(rùn)滑不足而損壞。

　　(5)檢修發(fā)動(dòng)機(jī)時(shí)，應(yīng)注意千萬(wàn)不能讓雜物進(jìn)入增壓器，以防損壞轉(zhuǎn)子。

　　(6)WD615機(jī)經(jīng)增壓后，空氣進(jìn)入中冷器，有幾道橡膠管連線(xiàn)，要求在出車(chē)前、修車(chē)中檢查其連接情況，防止松動(dòng)、脫落，以免造成增壓器失效和空氣短路進(jìn)缸。

　　(7)禁止柴油機(jī)長(zhǎng)時(shí)間急速運(yùn)轉(zhuǎn)(一般不超過(guò)5min)因怠速時(shí)機(jī)油油壓較低，不利于增壓器的潤(rùn)滑，容易使軸承過(guò)早磨損。

　　4 韓國(guó)斗山大宇廢氣渦輪增壓器常見(jiàn)的故障及排除

　　增壓器出現(xiàn)故障，不要匆忙的更換增壓器，應(yīng)該尋找和判斷故障原因和部位，并盡可能地加以排除。這樣可以避免換上增壓器后同樣的故障重復(fù)出現(xiàn)。

　　4.1壓氣機(jī)喘振。如果增壓器在工作過(guò)程中向氣缸內(nèi)輸送空氣量不足，空氣壓力將產(chǎn)生極大的波動(dòng)，在壓氣機(jī)端發(fā)出異響，如氣喘的響聲，這就是喘振。由于喘振，發(fā)動(dòng)機(jī)工作不平穩(wěn)，功率下降，排氣冒黑煙。

　　產(chǎn)生喘振的原因是進(jìn)氣系統(tǒng)堵塞，如空氣濾清器濾芯嚴(yán)重阻塞，進(jìn)氣管內(nèi)油污太多阻塞。增壓器的噴嘴環(huán)流通道發(fā)生變形也會(huì)造成喘振。最好是每次二級(jí)保養(yǎng)更換空氣濾芯，車(chē)運(yùn)行十萬(wàn)公里左右，清洗進(jìn)氣通道。

　　4.2增壓器在運(yùn)轉(zhuǎn)中發(fā)出雜音，發(fā)出金屬的撞擊，摩擦聲、或者產(chǎn)生振動(dòng)，是增壓器轉(zhuǎn)子和渦殼之間發(fā)生了變化，應(yīng)拆卸轉(zhuǎn)子檢修、調(diào)整。

　　4.3增壓器在運(yùn)轉(zhuǎn)中出現(xiàn)了強(qiáng)烈的震動(dòng)。這是由于轉(zhuǎn)子組不平衡，軸承損壞造成的，應(yīng)更換軸承及進(jìn)行轉(zhuǎn)子組的動(dòng)平衡校驗(yàn)。

　　4.4增壓壓力下降。該故障的主要原因是進(jìn)氣道堵塞，并進(jìn)入中冷器的進(jìn)氣道連接軟管松脫，破裂造成。

　　4.5增壓器突然停止運(yùn)行，發(fā)動(dòng)機(jī)功率下降。這是增壓器軸承損壞，轉(zhuǎn)子組燒死所致。應(yīng)更換軸承，如損壞嚴(yán)重應(yīng)更換增壓器總成。油封漏油也應(yīng)及時(shí)檢修更換。

寧波日興動(dòng)力科技有限公司柴油發(fā)動(dòng)機(jī)/工程機(jī)機(jī)械發(fā)動(dòng)機(jī)/船舶動(dòng)力/發(fā)電機(jī)組整體標(biāo)準(zhǔn)維修作業(yè)程序

一：按章施工

本公司對(duì)整臺(tái)發(fā)電機(jī)的維修，實(shí)行程序卡制度，并將整個(gè)工作流程分為以下11道工序。

1:發(fā)電機(jī)拆卸前的檢查項(xiàng)目。2:柴油機(jī)的拆卸項(xiàng)目。3:柴油機(jī)各部件的清洗。4:柴油機(jī)各部件的檢查及測(cè)量。5:柴油機(jī)所需更換的配件目錄。6:柴油機(jī)各部件的裝配。7:柴油機(jī)裝配完畢試機(jī)前的檢查項(xiàng)目。8:柴油機(jī)試機(jī)程序的各個(gè)檢查項(xiàng)目。9:柴油機(jī)返修項(xiàng)目。10:柴油機(jī)磨合期的各個(gè)檢查項(xiàng)目。11:柴油機(jī)磨合后正常運(yùn)行交付使用。

二：用戶(hù)須知

在整個(gè)維修過(guò)程中，我們要求客戶(hù)必須配合以下工作。1:客戶(hù)派出一名主管對(duì)整個(gè)工程進(jìn)行監(jiān)督管理。2：每道工序幸均須由工程總監(jiān)和客戶(hù)主管簽名作實(shí)。3：監(jiān)督主管在整個(gè)工程中，認(rèn)為施工者不按程序卡進(jìn)行操作，必須馬上予以制止，和維修組長(zhǎng)進(jìn)行交涉。4：若意見(jiàn)分岐，請(qǐng)和本公司營(yíng)業(yè)員聯(lián)系，直至達(dá)到意見(jiàn)統(tǒng)一后方可進(jìn)行施工。

三：檢修程序

A.機(jī)體和曲柄連桿機(jī)構(gòu)：1.氣缸體的損傷/氣缸體常見(jiàn)的損傷有：燒瓦、主軸承孔變形、裂紋、破碎、水道口腐蝕和配合表面磨損等。在外觀檢查時(shí)，應(yīng)無(wú)任何的裂紋和損傷，若發(fā)現(xiàn)有導(dǎo)致漏水、漏油、漏氣、損傷時(shí)，必須予以修理或更換。尤其對(duì)氣缸體與氣缸套接觸的密封環(huán)帶處有無(wú)穴蝕、腐蝕現(xiàn)象予以特別檢查。2.主軸承孔/對(duì)有燒瓦現(xiàn)象的缸體，要特別對(duì)主軸承孔孔徑予以測(cè)量，非標(biāo)主軸承孔必須予以修正。 3.凸輪軸孔/凸輪軸襯套表面露銅大于120度時(shí)，必須更換凸輪軸襯套，如果凸輪軸襯套磨損過(guò)度，也必須予以更換，否則會(huì)引起機(jī)油壓力過(guò)低，襯套如在座孔中轉(zhuǎn)動(dòng)，則必須檢查座孔的尺寸，超標(biāo)則修理座孔并換新襯套。4.氣缸套座孔/檢查氣缸廈門(mén)座孔的失圓度，不應(yīng)大于0。025mm，氣缸套座孔肩臺(tái)有無(wú)裂紋，氣缸套凸出量在0。15-0。20mm之間，新缸套裝入缸體后不應(yīng)有左右擺動(dòng)的現(xiàn)象。

B. 活塞、活塞環(huán)、活塞銷(xiāo)組件,

活塞的損壞現(xiàn)象有：1:活塞頂面的燒蝕。2:活塞環(huán)槽側(cè)壁的磨損及環(huán)岸斷裂。3:活塞銷(xiāo)孔孔徑變大，失圓。4:銷(xiāo)座部位裂紋。5:活塞初部拉傷。6:活塞初部磨損和馬橢圓。7:活塞環(huán)槽內(nèi)側(cè)有脊峰存在。8:活塞磨損過(guò)大。

C.連桿組件

連桿組件的主要損傷有：1:小頭襯套磨損。2:小頭襯套座孔和大頭軸瓦座孔磨損與變形。3:連桿的彎曲的扭曲。4:連桿螺釘或螺桿有裂紋、變長(zhǎng)、螺紋磨損或滑扣現(xiàn)象。5:連桿身有劃傷現(xiàn)象。6:連桿有燒瓦變形現(xiàn)象。在安裝連桿組件時(shí)，必須按正確的扭矩參數(shù)及正確的步驟進(jìn)行操作，而且必須對(duì)螺桿螺釘進(jìn)行復(fù)檢。

警告：安裝連桿組件，須由工程總監(jiān)親自操作。對(duì)于損傷的連桿組件，必須予以報(bào)廢，否則會(huì)引起連桿斷裂，擊破氣缸體，打斷曲軸的危險(xiǎn)。

D.曲軸、飛輪組件:由軸的主要損傷有：軸頸磨損，曲軸裂紋和斷裂，燃瓦而造成的燒蝕。如果曲軸軸頸的失圓度大于0.05mm時(shí)，則需磨削曲軸軸頸。對(duì)于燒瓦嚴(yán)重的曲軸，由于其金相組織已發(fā)生變化，一般不建議再次使用，有裂紋現(xiàn)象的曲軸必須予報(bào)廢，否則會(huì)有斷裂的可能。

警告：安裝曲軸、飛輪組件、須由工程總監(jiān)親自操作，按標(biāo)準(zhǔn)的扭矩和正確的步驟執(zhí)行，主軸承蓋螺釘必須復(fù)檢。

E.氣缸蓋和配氣機(jī)構(gòu),1、氣缸蓋/氣缸蓋和氣缸體接合平面，氣門(mén)導(dǎo)管孔，氣門(mén)座圓孔，噴油器孔，冷卻水套壁等處，易產(chǎn)生裂紋，可用目檢，水壓試驗(yàn)進(jìn)行檢查。氣缸蓋與氣缸體接合平面不平時(shí)，建議上磨床修理，每次加工量為0.10mm左右，加工極限為1.00mm。噴油器缸套有滲漏或損傷會(huì)引起漏水，應(yīng)對(duì)噴油器銅套予以換新。有裂紋的缸蓋建議予以報(bào)廢，否則會(huì)引起漏水現(xiàn)象。2、配氣機(jī)構(gòu): 1)氣門(mén)座圈和氣門(mén)導(dǎo)管/個(gè)別機(jī)組的氣門(mén)座圈和氣門(mén)導(dǎo)管需予以磨削，磨削量必須正確，否則會(huì)引起氣門(mén)碰撞活塞，氣門(mén)和氣門(mén)導(dǎo)管卡死，機(jī)油耗量劇增等故障。此工作須由工程總監(jiān)親自操作.2）氣門(mén)彈簧/檢查氣門(mén)彈簧的長(zhǎng)度和彈力，彈簧太軟會(huì)造成氣門(mén)跳動(dòng)，使氣門(mén)和氣門(mén)座加劇磨損，也會(huì)破壞氣門(mén)正時(shí),氣門(mén)和活塞發(fā)生碰撞。不合格的彈簧必須予以報(bào)廢。3）氣門(mén)和氣門(mén)座圈的研磨/采用研磨膏研磨氣門(mén)，使氣門(mén)和氣門(mén)座圈呈線(xiàn)性接觸，所有氣門(mén)研磨完畢，必須將研磨膏清洗干凈（特別注意要將氣門(mén)導(dǎo)管內(nèi)的研磨膏清洗干凈）。4）氣門(mén)上下蓋/檢查有無(wú)裂紋，不合格則予以報(bào)廢。5）凸輪軸/檢查凸輪軸的凸輪型面積軸頸處有無(wú)裂紋、凹坑、腐蝕、擦傷，檢查齒輪有無(wú)裂紋、齒斷裂或齒面凹坑，不合格則予以報(bào)廢，否則會(huì)引起冒黑煙、功率虧損、擊破缸體的危險(xiǎn)。6）凸輪從動(dòng)件/檢查從動(dòng)軸外有無(wú)超標(biāo)，不合格則予以報(bào)廢。檢查滾輪表面有無(wú)麻點(diǎn)，轉(zhuǎn)動(dòng)是否靈活，是否磨損過(guò)度，不合格則予以報(bào)廢。檢查滾輪銷(xiāo)及銷(xiāo)孔是否磨損過(guò)度，超標(biāo)則予以報(bào)廢。檢查隨動(dòng)臂有無(wú)裂紋，如有則予以報(bào)廢。7）氣門(mén)及噴油器推桿/球頭端有無(wú)磨損過(guò)度，推桿是否失圓，有無(wú)彎曲，不合格則則予以報(bào)廢。8）播臂/檢查有無(wú)裂紋，與丁字壓板的接觸凸面有無(wú)磨損或損傷，搖臂襯套內(nèi)徑有無(wú)超標(biāo)。檢查搖臂軸的磨損，超標(biāo)則。予以報(bào)廢9）丁字壓板/檢查丁字壓板孔徑有無(wú)超標(biāo)，丁字壓板的螺紋是否磨損和損傷，為合格則予以報(bào)廢。

警告：凸輪從動(dòng)件為最關(guān)鍵而且容易出問(wèn)題的配件，需予以特別檢查，否則會(huì)出現(xiàn)冒黑煙，功率虧損，擊破氣缸體曲軸的危險(xiǎn)。

South Korea Doosan Daewoo diesel engine exhaust gas turbocharger correct use and fault diagnosis ( exhaust gas turbine supercharger; fault diagnosis; )

The effect of turbocharger life factors, fault and diagnosis are analyzed, and the points for attention in use, is intended to reduce the supercharger failure, prolong the service life, reduce maintenance cost.

In recent years, along with the motor vehicle replacement, some heavy duty diesel vehicles generally used a turbocharger, but in the use of often occurs in the exhaust gas turbine supercharger damaged early fault, analyse its reason, is mainly used for turbocharger, improper maintenance caused by. The influence of turbocharger life factors, fault and diagnosis are analyzed, and the points for attention in use, is intended to reduce the supercharger failure, prolong the service life, reduce maintenance cost.

The 1exhaust gas turbocharger of the basic knowledge and principle of work

Turbocharger is used to increase engine power and reduce emissions of major parts. Turbocharger itself is not a kind of power supply, it uses the residual energy in the exhaust of the engine to work, its role is to provide more compressed air engine. It uses the engine exhaust gas energy, driving the turbine rotating speed, driving the coaxial with turbine compressor impeller rotating speed, press the compressed air into the engine cylinder, increases the engine's air volume, for more complete combustion of the fuel, thereby increasing the power of the engine, reduce fuel consumption, at the same time as the combustion conditions improve, reduce exhaust emissions of harmful substances, capable of reducing noise.

Diesel engine performance through the pressurization later changed, it makes the power of diesel engine is greatly improved, turbocharged engine power can be increased by 20%～ 40%, WD615 machine as an example, the engine mechanical efficiency, turbocharged engine auxiliary system of the power consumption is increased a little, although because of an outbreak of pressure, the the friction surface of the friction loss has increased, but the engine power increased, the mechanical efficiency is increased by about 8% or so. Reduced fuel consumption, after the booster inlet pressure, improve combustion conditions, mechanical efficiency, reduce oil consumption of engine unit, power quality is greatly reduced, but the engine after pressurization also brought new problems, such as: the engine so that the mechanical load is increased, the heat load of an engine to increase and so on.

2Influence Factors of service life of turbocharger

Use we found, turbocharger damage and wear always in diesel engine and its nearby after a failure occurs, diesel engine with many abnormal conditions will cause the damage of turbocharger. Turbocharger failure,40% is due to poor lubrication caused,40% is the result of external impurities through the turbocharger caused by other reasons,20%.

The 2.1lubricating oil. Lubricating oil used for lubricating and cooling the supercharger, but when the turbocharger when in normal work, the rotating speed of up to the minute tens of thousands to ten rotates, lubricating oil is hit into foam, its cooling and lubricating performance, therefore lubrication system must guarantee to provide sufficient lubrication oil. When600℃high temperature of exhaust gas through the turbine chamber, the bearing seat can not get enough lubrication and cooling, lubricating oil in the annular oil on the wall of coking, gradually blocked oil.

Lubricating oil if not clean, will soon damaged turbocharger internal parts. Such as containing dust, mud sediment and metal particles in the lubricating oil can quickly destroy the parts fit clearance, scratching and wear of bearing surface. All these will cause the turbine shaft resistance and lose balance, so that the rotational speed of the shaft down, resulting in engine power loss increases, and the rotational imbalance will soon lead to a turbocharger parts damage.

If the oil quality grade aging, oil additives can not meet the large work load of turbocharged diesel engine lubrication requirements, lubricating oil will be accelerated oxidation metamorphism, also aggravate the diesel engine and turbocharger parts wear.

Diesel engine starting, flameout operation method is not correct it will seriously affect the life of turbocharger. If the starting of the diesel engine, once the speed to rise too high, the lubricating oil can not be timely arrival of turbocharger bearing and accelerated wear. Diesel engine flameout, if not the first to make turbocharger cooled, and all of a sudden flameout, to stop the supply of oil will cause the turbocharger, turbocharger internal parts overheat, bearing oil passage oil carbonization blocking oil, would have killed risk bearing.

Seal ring leakage caused by turbine rear carbon deposit, will make the rotating parts rotation of Shibuya, and loss of power. Rotating parts unbalance is caused by the seal ring leakage is one of the important reasons. The crank vent or supercharger oil return pipe plug or the resistance is too large, can also cause the seal ring leakage.

2.2air intake system. Turbocharger working stand or fall is also dependent on the intake system, only supplies enough, clean air to ensure the supercharger long-term trouble-free, prolonging life. Therefore, should be regularly checked all the inlet pipe and hose seal, to prevent leakage. If the compressor to diesel engine intake pipe leakage, reduce the amount of air, will cause the black smoke for diesel engine. When the larger particles of dust or sand into opportunity immediately damaged turbocharger compressor. The smaller particles will also make the work wheel blades bending or cutting, and make it out of balance, causing a bearing and seal ring wear intensifies. Unbalanced rotor and bearing when a collision occurs, the bearing oil passage is gradually reduced, leading to poor lubrication. As the bearing wear, with increasing gap, so that the compressor or turbine blade against shell, the fault signal is a lot more noise than usual.

Air intake system and the intake resistance should be small, if the air filter is clogged, the intake resistance increases, the inflatable amount is reduced, increasing the power loss, at the same time, the compressor side of the seal ring will be due to the pressure difference is too big and leaked, causing lubricating oil consumption is too large, the fault is marked in the compressor work wheel blades appear behind a layer of dark lubricating oil film.

2.3emissions. Very small particles in the exhaust gas into the turbine, and the particles into the compressor as a result, will lead to the damage of turbocharger.

Diesel fuel amount is too large, the intake resistance, will make the combustion chamber combustible mixed gas exhaust overheating caused by too strong, causing the turbine casing and oil overheating, the exhaust gas from the exhaust pipe to the turbine chamber passage leak will reduce the turbine turbine speed, increasing the smoke, also can make the turbine housing overheating. All these will lead to the interior carbon deposit and turbine blade corrosion.

Lubricating oil pressure is too high, the lubricating oil through the sealing ring into the turbines will result in the turbine chamber, carbon deposition.

The 3exhaust gas turbochargers use matters needing attention

Exhaust gas turbine supercharger often works under high temperature, into the exhaust gas turbine end at the temperature of 600℃. Supercharger Rotor with tens of thousands to ten per minute to rotate at high speed, in order to ensure the normal work of the supercharger, the use should pay attention to the following points: (1) use the correct grade of lubricating oil, and the regular replacement. For turbocharged diesel engine should be at least CD stage supercharged engine.

(2) engine, especially in the winter, after engine ignition, should be idle a few minutes, ten million cannot banging accelerator, to prevent damage to the turbocharger oil seal.

(3) before the engine flameout, should also be idle a few minutes, let the engine, turbocharger rotor speed down later to prevent stalling, bombarded the throttle, the turbocharger speed is very high, all of a sudden flameout, machine oil pump not nonsense, Supercharger Rotor in high-speed inertial movement, dry bad bearing wear.

(4) due to the frequent under high temperature operation, to the turbocharger lubricating oil pipeline due to high temperature, the internal oil easy to have part of the coke, which will cause the supercharger bearing lubrication and damage.

(5) as part of the engine, should pay attention not to let the debris into the supercharger, to prevent damage to the rotor.

(6) WD615by pressurized, air enters the intercooler, a couple of rubber pipe connection, requirements, before driving car check their connections, to prevent loosening, fall off, so as to avoid the turbocharger failure and short circuit of air cylinder.

(7) prohibit the diesel engine for a long time racing ( less than 5min ) for idle speed oil pressure is low, is not conducive to the turbocharger lubrication, easy to cause premature bearing wear.

The 4exhaust gas turbocharger of common breakdown and eliminate

Turbocharger failure, not to rush to replace supercharger, should seek and fault reasons and positions, and as far as possible to exclude. This can be avoided in the supercharger the same fault repeated.

4.1compressor surge. If the turbocharger in the working process to the cylinder air volume, air pressure will produce great volatility, in air compressor end sends out the different bang, such as wheezing sound, this is the surge. Since the surge, the engine working is not stable, power down, black smoke exhaust.

Surge is the cause of the intake system blockage, such as air cleaner element severe obstruction, air intake pipe oil too much congestion. Turbocharger nozzle circulation channel deformation will cause surge. It is best for each two maintenance replacement air filter, car runs one hundred thousand kilometers, cleaning air inlet passage.

4.2 supercharger in operation emits a sound, making the metal bump, friction sound, or vibration, the turbocharger rotor and the volute are between changed, should remove rotor maintenance, adjustment.

In the operation of the4.3turbocharger appeared strong shock. This is due to the rotor group imbalance, bearing damage, replace the bearing and rotor dynamic balancing.

4.4pressure drop. This is the main reason of failure of inlet plug, and into the cooler inlet port connected to the hose loose, caused by ruptured.

4.5 supercharger suddenly stopped running, engine power is reduced. This is the turbocharger rotor beari, ng damage, caused by the group. Should replace the bearings, such as serious damage to replace the turbocharger assembly. Seal leak should also be timely maintenance and replacement.

Nikko Ningbo power science and technology limited company diesel engine / engineering mechanical engine / ship power / power unit standard repair procedures

A: according to construction

The company of the whole generator repair, execute program card system, and the whole process is divided into the following11 procedures.

1: generator removing before the examination project. The 2: diesel engine disassembly project. 3: diesel engine parts cleaning. 4: diesel engine parts inspection and measurement. 5: diesel engine replacement parts catalog. 6: assemblage of parts of a diesel engine. 7: diesel engine assembly line test before the examination project. 8: diesel engine test procedures of various examination items. 9: diesel engine repair project. 10: diesel engine running-in period various examination items. 11: diesel engine running-in normal work after delivery.

Two: User guidelines

In the repair process, we request the customer to cooperate with the following work. 1: customer sent a supervisor on the project supervision and management. 2: each process shall be required by the director of engineering and to charge customers signed for confirmation. 3: Supervision of the supervisor in the whole project construction, that does not press a program card operation, must immediately be stopped, and repair group representations. 4: if the opinion divergence, and the company please contact the clerk, until it reaches the agreement before construction.

Three: maintenance program

A. body and a crank and connecting rod mechanism:1 cylinder body damage / cylinder common injury: burn tile, main bearing hole deformation, crack, breakage, the mouth of the water channel matching surface corrosion and abrasion. On visual inspection, should be no crack and damage, if found to have lead to water leakage, oil leakage, leakage, damage, it must be repaired or replaced. Especially for the cylinder body and the cylinder sleeve contacts the sealing ring has no pitting, corrosion phenomenon to be special inspection. 2main bearing hole of burning tile / phenomenon of the cylinder, particularly on the main bearing hole of aperture to be measured, non-standard main bearing hole must be corrected. The 3cam shaft hole and the camshaft bushing surface exposed copper is greater than 120 degrees, must be replaced if the camshaft bushing, camshaft bushing wear is excessive, also must be replaced, otherwise it would cause the engine oil pressure is too low, such as in the base hole bushing rotate, it must be checked seat hole size, exceed the standard, repair seat hole and renewed bush. 4cylinder block bore / check cylinder Xiamen seat hole non roundness, should not be greater than 0. 025mm, cylinder sleeve hole shoulder have no crack, cylinder liner projection in 0. 15-0. Between 20mm, new cylinder is sheathed in the cylinder should not swing phenomenon.

B. piston, piston ring, piston pin assembly,

Piston damage phenomena are: 1: piston top surface ablation. The 2: piston ring groove side wall wear and ring fracture. 3: piston pin hole aperture greatens, out of round. The 4: pin base crack. 5: piston initial strain. 6: early wear and horse ellipse piston. The 7: piston ring groove medial ridge peak exists. 8: piston wear too large.

C. connecting rod assembly

Connecting rod assembly of major injury are: 1: head liner wear. 2: small end bushing seat hole and the big end bearing saddle bore wear and deformation. 3: rod bending distortion. Connecting rod bolt or screw4: crack, variable length, thread wear or slipping buckles. 5: connecting rod body scratch phenomenon. 6: connecting rod has a tile deformation phenomenon. In the installation of connecting rod assembly, must press the correct torque parameters and the correct procedure, and must be inspected for screw screw.

Warning: installing a linkage assembly, shall be determined by the project manager to operate personally. For the damage of connecting rod assembly, must be scrapped, otherwise it will cause the connecting rod fracture, break the cylinder block, crankshaft and the risk of break.

Crankshaft, flywheel assembly: D. from the axis of the main shaft neck injury: abrasion, crack and fracture, burning tile resulting ablation. If the crankshaft out of roundness is greater than 0.05mm, will be grinding crankshaft. For tile serious crankshaft, due to its metallographic structure has changed, is generally not recommended to use again, crack phenomenon of the crankshaft must be scrapped, or there will be the possible fracture.

Warning: installing crankshaft, flywheel assembly, shall be determined by the project director in person operation, according to the criteria of the torque and the correct steps, main bearing cover screws must recheck.

E. cylinder cover and a gas distribution mechanism,1, cylinder head and cylinder cover and the cylinder body joint plane, valve guide hole, the valve seat hole, the injector hole, water cooling wall, easy to crack, available visual inspection, pressure test check. The cylinder cover and the cylinder body joint planes are not usually, advice on grinding machine repair, each processing capacity of around 0.10mm, processing limit is 1.00mm. The injector cylinder leakage or damage will cause the water leakage, deal with the fuel injector copper sets to be renewed. Cracked cylinder head suggested to be scrapped, otherwise it will cause the water leakage phenomenon. 2, gas distribution mechanism:1) the valve seat and the valve guide / individual units of the valve seat and the valve guide should be grinding, grinding amount must be correctly, otherwise it will cause impact piston valve, valve and valve catheter blocked, oil consumption increases fault. This work is required by the project director personally operation .2) valve spring / check valve spring length and elastic, soft spring will result in valve beating, the valve and valve seat exacerbates wear, will also destroy the valve timing, valve and piston collisions. Unqualified spring must be scrapped. 3) valve and valve seat ring polishing / grinding paste grind the valve, the valve and valve seat ring a linear contact, all valve grinding is finished, must be grinding paste clean (with particular attention to the valve within the conduit