摘 要:從實際工(gong)(gong)(gong)(gong)作來(lai)看,在零(ling)(ling)件加(jia)(jia)工(gong)(gong)(gong)(gong)過程中,其(qi)精(jing)(jing)度會受(shou)到機械(xie)加(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)藝的(de)影響。為了提(ti)高(gao)(gao)零(ling)(ling)件加(jia)(jia)工(gong)(gong)(gong)(gong)的(de)精(jing)(jing)度,便(bian)有必要(yao)提(ti)高(gao)(gao)機械(xie)加(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)藝的(de)水平。文章在分析機械(xie)加(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)藝對零(ling)(ling)件加(jia)(jia)工(gong)(gong)(gong)(gong)精(jing)(jing)度的(de)影響的(de)基礎上,進一步(bu)對相應(ying)的(de)控制策略進行探(tan)討,希望以(yi)此為零(ling)(ling)件加(jia)(jia)工(gong)(gong)(gong)(gong)精(jing)(jing)度的(de)提(ti)高(gao)(gao)提(ti)供一些具有價(jia)值的(de)參考憑據(ju)。
在零(ling)(ling)(ling)件加(jia)(jia)工(gong)(gong)(gong)(gong)過程中,會(hui)利(li)(li)用到(dao)(dao)機(ji)械加(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)藝(yi)(yi)(yi)。對于機(ji)械加(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)藝(yi)(yi)(yi)來說,即利(li)(li)用機(ji)械的(de)力量對零(ling)(ling)(ling)件進行加(jia)(jia)工(gong)(gong)(gong)(gong)。但(dan)是,由于零(ling)(ling)(ling)件對加(jia)(jia)工(gong)(gong)(gong)(gong)的(de)精(jing)(jing)度(du)(du)要求非常高(gao),所以如果(guo)機(ji)械加(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)藝(yi)(yi)(yi)使用不合理,便會(hui)使零(ling)(ling)(ling)件加(jia)(jia)工(gong)(gong)(gong)(gong)的(de)精(jing)(jing)度(du)(du)受到(dao)(dao)很大程度(du)(du)的(de)影響(xiang)。從零(ling)(ling)(ling)件加(jia)(jia)工(gong)(gong)(gong)(gong)精(jing)(jing)度(du)(du)的(de)提升角(jiao)度(du)(du)來看,文章對“機(ji)械加(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)藝(yi)(yi)(yi)對零(ling)(ling)(ling)件加(jia)(jia)工(gong)(gong)(gong)(gong)精(jing)(jing)度(du)(du)的(de)影響(xiang)及(ji)控制”進行分析與探(tan)討意(yi)義重大。
機械(xie)(xie)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)藝,即(ji):基于(yu)機械(xie)(xie)零(ling)(ling)件(jian)(jian)以及(ji)工(gong)(gong)(gong)(gong)件(jian)(jian)制造期間,采(cai)取有關(guan)的(de)(de)(de)(de)(de)(de)(de)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)藝方(fang)法(fa)更改毛(mao)(mao)(mao)坯(pi)(pi)(pi),并(bing)(bing)進(jin)行加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong),進(jin)一(yi)(yi)(yi)(yi)步對毛(mao)(mao)(mao)坯(pi)(pi)(pi)和(he)零(ling)(ling)件(jian)(jian)間的(de)(de)(de)(de)(de)(de)(de)吻合(he)度(du)(du)(du)(du)(du)進(jin)行加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)。從(cong)實(shi)(shi)際(ji)工(gong)(gong)(gong)(gong)作(zuo)角度(du)(du)(du)(du)(du)來看,基于(yu)機械(xie)(xie)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)藝實(shi)(shi)施期間,對加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)的(de)(de)(de)(de)(de)(de)(de)毛(mao)(mao)(mao)坯(pi)(pi)(pi)打磨以及(ji)零(ling)(ling)件(jian)(jian)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)精(jing)(jing)(jing)(jing)(jing)度(du)(du)(du)(du)(du)的(de)(de)(de)(de)(de)(de)(de)要求(qiu)是(shi)非(fei)常(chang)苛刻的(de)(de)(de)(de)(de)(de)(de)。通(tong)常(chang)情況下,需(xu)(xu)遵循“由粗(cu)到(dao)(dao)細”的(de)(de)(de)(de)(de)(de)(de)基本加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)流程(cheng)(cheng)。首先,對于(yu)粗(cu)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)來說,即(ji)打磨毛(mao)(mao)(mao)坯(pi)(pi)(pi)和(he)零(ling)(ling)件(jian)(jian)的(de)(de)(de)(de)(de)(de)(de)大(da)(da)體(ti),然后(hou)(hou)(hou)確(que)保(bao)(bao)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)出(chu)來的(de)(de)(de)(de)(de)(de)(de)毛(mao)(mao)(mao)坯(pi)(pi)(pi)和(he)零(ling)(ling)件(jian)(jian)大(da)(da)小(xiao)的(de)(de)(de)(de)(de)(de)(de)精(jing)(jing)(jing)(jing)(jing)準(zhun)性。其次,對于(yu)精(jing)(jing)(jing)(jing)(jing)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)來說,需(xu)(xu)通(tong)過精(jing)(jing)(jing)(jing)(jing)細計算(suan),將精(jing)(jing)(jing)(jing)(jing)準(zhun)的(de)(de)(de)(de)(de)(de)(de)毛(mao)(mao)(mao)坯(pi)(pi)(pi)和(he)零(ling)(ling)件(jian)(jian)大(da)(da)小(xiao)值求(qiu)解(jie)出(chu)來,并(bing)(bing)進(jin)一(yi)(yi)(yi)(yi)步基于(yu)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)期間完成相(xiang)(xiang)應的(de)(de)(de)(de)(de)(de)(de)精(jing)(jing)(jing)(jing)(jing)密(mi)制造,最后(hou)(hou)(hou)確(que)保(bao)(bao)毛(mao)(mao)(mao)坯(pi)(pi)(pi)和(he)零(ling)(ling)件(jian)(jian)的(de)(de)(de)(de)(de)(de)(de)大(da)(da)小(xiao)值得精(jing)(jing)(jing)(jing)(jing)準(zhun)度(du)(du)(du)(du)(du)。加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)作(zuo)完成之后(hou)(hou)(hou),有必要進(jin)行相(xiang)(xiang)應的(de)(de)(de)(de)(de)(de)(de)檢驗工(gong)(gong)(gong)(gong)作(zuo),通(tong)過檢驗把誤差超出(chu)一(yi)(yi)(yi)(yi)定范圍的(de)(de)(de)(de)(de)(de)(de)零(ling)(ling)件(jian)(jian)淘(tao)汰棄用,在(zai)得到(dao)(dao)全部(bu)精(jing)(jing)(jing)(jing)(jing)準(zhun)的(de)(de)(de)(de)(de)(de)(de)零(ling)(ling)部(bu)件(jian)(jian)之后(hou)(hou)(hou)再進(jin)行包裝工(gong)(gong)(gong)(gong)作(zuo)。從(cong)整體(ti)角度(du)(du)(du)(du)(du)來看,機械(xie)(xie)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)藝流程(cheng)(cheng)為(wei)整體(ti)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)當中非(fei)常(chang)關(guan)鍵的(de)(de)(de)(de)(de)(de)(de)一(yi)(yi)(yi)(yi)部(bu)分,在(zai)確(que)保(bao)(bao)其嚴(yan)謹性的(de)(de)(de)(de)(de)(de)(de)條件(jian)(jian)下,才能(neng)夠保(bao)(bao)證生產結(jie)果(guo)的(de)(de)(de)(de)(de)(de)(de)成功率。通(tong)常(chang)而言,機械(xie)(xie)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)藝流程(cheng)(cheng)即(ji)把毛(mao)(mao)(mao)坯(pi)(pi)(pi)改造成為(wei)合(he)格的(de)(de)(de)(de)(de)(de)(de)產品的(de)(de)(de)(de)(de)(de)(de)一(yi)(yi)(yi)(yi)道工(gong)(gong)(gong)(gong)序,其中零(ling)(ling)件(jian)(jian)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)以及(ji)機械(xie)(xie)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)便是(shi)最為(wei)關(guan)鍵的(de)(de)(de)(de)(de)(de)(de)環節。基于(yu)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)期間,需(xu)(xu)考慮環境影(ying)響(xiang)因素,在(zai)受到(dao)(dao)環境因素影(ying)響(xiang)之下,零(ling)(ling)件(jian)(jian)的(de)(de)(de)(de)(de)(de)(de)精(jing)(jing)(jing)(jing)(jing)度(du)(du)(du)(du)(du)將會受到(dao)(dao)很大(da)(da)程(cheng)(cheng)度(du)(du)(du)(du)(du)的(de)(de)(de)(de)(de)(de)(de)影(ying)響(xiang)。此外(wai),由于(yu)零(ling)(ling)件(jian)(jian)精(jing)(jing)(jing)(jing)(jing)度(du)(du)(du)(du)(du)控(kong)制較為(wei)復雜,所以在(zai)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)過程(cheng)(cheng)中需(xu)(xu)嚴(yan)格按照(zhao)相(xiang)(xiang)關(guan)規(gui)范標準(zhun)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)以執行,進(jin)一(yi)(yi)(yi)(yi)步確(que)保(bao)(bao)零(ling)(ling)件(jian)(jian)加(jia)(jia)(jia)(jia)(jia)(jia)(jia)工(gong)(gong)(gong)(gong)的(de)(de)(de)(de)(de)(de)(de)高精(jing)(jing)(jing)(jing)(jing)度(du)(du)(du)(du)(du)。
從實際工作來看,機械加(jia)工工藝(yi)會(hui)對(dui)零件(jian)加(jia)工的精度產生(sheng)一定的影(ying)響,總結起(qi)來這些影(ying)響因素主要(yao)包括(kuo):
2.1 內在影(ying)響因(yin)素(su)
內在因(yin)素(su)是(shi)機(ji)(ji)(ji)械(xie)(xie)(xie)加工(gong)(gong)工(gong)(gong)藝對(dui)零(ling)(ling)(ling)件(jian)(jian)加工(gong)(gong)精度(du)產(chan)生影(ying)響(xiang)(xiang)(xiang)的(de)(de)一大關鍵因(yin)素(su),主(zhu)要(yao)包括:①機(ji)(ji)(ji)械(xie)(xie)(xie)加工(gong)(gong)系統當(dang)中(zhong)存(cun)在幾何精度(du)誤(wu)差(cha);②在機(ji)(ji)(ji)械(xie)(xie)(xie)安裝過程中(zhong)存(cun)在操作不(bu)規范的(de)(de)情況。通過認(ren)真分析可(ke)知,內在影(ying)響(xiang)(xiang)(xiang)因(yin)素(su)對(dui)零(ling)(ling)(ling)件(jian)(jian)加工(gong)(gong)精度(du)的(de)(de)影(ying)響(xiang)(xiang)(xiang)較大,且此(ci)類因(yin)素(su)也很難(nan)消(xiao)除。當(dang)機(ji)(ji)(ji)械(xie)(xie)(xie)存(cun)在幾何精度(du)誤(wu)差(cha)的(de)(de)情況下,會(hui)導致加工(gong)(gong)之后(hou)所生產(chan)出來(lai)的(de)(de)零(ling)(ling)(ling)件(jian)(jian)存(cun)在一定(ding)的(de)(de)誤(wu)差(cha)。對(dui)于(yu)機(ji)(ji)(ji)械(xie)(xie)(xie)加工(gong)(gong)工(gong)(gong)藝來(lai)說,對(dui)零(ling)(ling)(ling)件(jian)(jian)加工(gong)(gong)設(she)備的(de)(de)要(yao)求(qiu)是(shi)非常(chang)高的(de)(de),設(she)備的(de)(de)好壞程度(du)將會(hui)對(dui)生產(chan)零(ling)(ling)(ling)件(jian)(jian)的(de)(de)精度(du)產(chan)生直接性的(de)(de)影(ying)響(xiang)(xiang)(xiang)。通常(chang)而言,零(ling)(ling)(ling)件(jian)(jian)的(de)(de)加工(gong)(gong)機(ji)(ji)(ji)械(xie)(xie)(xie)屬于(yu)比(bi)較大規模的(de)(de)組(zu)(zu)合(he)型機(ji)(ji)(ji)械(xie)(xie)(xie),此(ci)類機(ji)(ji)(ji)械(xie)(xie)(xie)可(ke)以(yi)使零(ling)(ling)(ling)件(jian)(jian)的(de)(de)精度(du)要(yao)求(qiu)得到(dao)(dao)有(you)效滿足。基(ji)于(yu)組(zu)(zu)合(he)型機(ji)(ji)(ji)械(xie)(xie)(xie)工(gong)(gong)作過程中(zhong),安裝機(ji)(ji)(ji)械(xie)(xie)(xie)是(shi)不(bu)可(ke)或缺的(de)(de)步驟(zou),并(bing)且機(ji)(ji)(ji)械(xie)(xie)(xie)的(de)(de)各(ge)個組(zu)(zu)合(he)成分存(cun)在很高的(de)(de)融合(he)度(du),倘若在安裝期間未(wei)能安裝好機(ji)(ji)(ji)組(zu)(zu),那(nei)么會(hui)導致零(ling)(ling)(ling)件(jian)(jian)精度(du)受到(dao)(dao)影(ying)響(xiang)(xiang)(xiang)。此(ci)外,基(ji)于(yu)平常(chang)工(gong)(gong)作期間,磨損的(de)(de)存(cun)在,也會(hui)導致機(ji)(ji)(ji)械(xie)(xie)(xie)各(ge)組(zu)(zu)成部(bu)分出現微(wei)小的(de)(de)縫隙,這樣(yang)也會(hui)對(dui)零(ling)(ling)(ling)件(jian)(jian)的(de)(de)精度(du)造(zao)成影(ying)響(xiang)(xiang)(xiang)。總之,需重視內在影(ying)響(xiang)(xiang)(xiang),并(bing)采取(qu)有(you)效排除措施,進而確保零(ling)(ling)(ling)件(jian)(jian)加工(gong)(gong)的(de)(de)精準度(du)。
2.2 受力影響(xiang)因素
對于機械加(jia)(jia)工(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)藝系(xi)統(tong)來說,在(zai)(zai)(zai)運(yun)行(xing)期(qi)間(jian),通常會(hui)發(fa)生(sheng)(sheng)系(xi)統(tong)受(shou)(shou)(shou)力(li)(li)(li)(li)變形(xing)的(de)(de)(de)(de)(de)問題,導致系(xi)統(tong)發(fa)生(sheng)(sheng)位置(zhi)以(yi)及形(xing)狀方(fang)面的(de)(de)(de)(de)(de)變化,進(jin)一(yi)步使(shi)系(xi)統(tong)的(de)(de)(de)(de)(de)正常、安全運(yun)行(xing)受(shou)(shou)(shou)到(dao)影(ying)響(xiang)(xiang)(xiang)。總結起來,受(shou)(shou)(shou)力(li)(li)(li)(li)影(ying)響(xiang)(xiang)(xiang)因素體現(xian)(xian)在(zai)(zai)(zai)兩大方(fang)面:一(yi)方(fang)面,系(xi)統(tong)存在(zai)(zai)(zai)較強的(de)(de)(de)(de)(de)實際運(yun)行(xing)能力(li)(li)(li)(li)。當系(xi)統(tong)在(zai)(zai)(zai)實際運(yun)行(xing)期(qi)間(jian),所(suo)使(shi)用(yong)的(de)(de)(de)(de)(de)刀(dao)具以(yi)及夾具等(deng)構(gou)件都(dou)需要(yao)(yao)承受(shou)(shou)(shou)非常強的(de)(de)(de)(de)(de)工(gong)(gong)(gong)(gong)作(zuo)壓力(li)(li)(li)(li),當受(shou)(shou)(shou)到(dao)時間(jian)的(de)(de)(de)(de)(de)影(ying)響(xiang)(xiang)(xiang)之(zhi)下,便易產(chan)生(sheng)(sheng)相對位置(zhi)的(de)(de)(de)(de)(de)變化,或在(zai)(zai)(zai)受(shou)(shou)(shou)力(li)(li)(li)(li)的(de)(de)(de)(de)(de)作(zuo)用(yong)下發(fa)生(sheng)(sheng)形(xing)變。另一(yi)方(fang)面,系(xi)統(tong)的(de)(de)(de)(de)(de)各個部(bu)件會(hui)受(shou)(shou)(shou)到(dao)多方(fang)作(zuo)用(yong)力(li)(li)(li)(li),主要(yao)(yao)表(biao)現(xian)(xian)為既要(yao)(yao)承受(shou)(shou)(shou)系(xi)統(tong)自身帶來的(de)(de)(de)(de)(de)壓力(li)(li)(li)(li),又要(yao)(yao)承受(shou)(shou)(shou)加(jia)(jia)工(gong)(gong)(gong)(gong)零(ling)件施加(jia)(jia)的(de)(de)(de)(de)(de)壓力(li)(li)(li)(li);此外,還包括了部(bu)件和(he)部(bu)件之(zhi)間(jian)產(chan)生(sheng)(sheng)的(de)(de)(de)(de)(de)摩擦力(li)(li)(li)(li)。顯然,在(zai)(zai)(zai)受(shou)(shou)(shou)力(li)(li)(li)(li)的(de)(de)(de)(de)(de)影(ying)響(xiang)(xiang)(xiang)下,零(ling)件的(de)(de)(de)(de)(de)加(jia)(jia)工(gong)(gong)(gong)(gong)精(jing)度便會(hui)受(shou)(shou)(shou)到(dao)一(yi)定程度的(de)(de)(de)(de)(de)影(ying)響(xiang)(xiang)(xiang)。
2.3 熱變影響因素
在機械加工工藝應用過程中,對零件加工精度的熱變影響因素主要分為三類:①刀具熱變。零件加工切割過程中,需使用到相應的刀具,為了使零件符合標準,有時需要反復切割,這個過程便會有摩擦力形成,進而產生大量的熱量,熱量的存在進一步易使零件發生形變,最終使零件的精度受到影響;②工件熱變形。當零件長度較長的情況下,而機械加工工藝又對此類零件有較高的精度要求,這樣便會使零件的精度受到很大程度的影響;③機床自身及結構熱變形。對于機床自身來說,其和一些構件在運行期間會有產生相互作用,致使機床自身部分或者整體溫度上升。當溫度上升的情況下,機床自身的結構契合度便會受到很大程度的影響[5]。而當在高溫(wen)的(de)(de)(de)條(tiao)件下(xia),機(ji)床的(de)(de)(de)一(yi)(yi)些(xie)部分會呈(cheng)(cheng)現緊密(mi)的(de)(de)(de)狀(zhuang)況(kuang),另一(yi)(yi)部分則會在結構上產生細微(wei)的(de)(de)(de)縫(feng)隙,進一(yi)(yi)步致使加工(gong)零(ling)件的(de)(de)(de)精(jing)準度(du)(du)偏(pian)離理想狀(zhuang)態(tai)。此外,在機(ji)床發熱的(de)(de)(de)情況(kuang)下(xia),會使機(ji)床的(de)(de)(de)正(zheng)常(chang)運行(xing)受到很大程(cheng)度(du)(du)的(de)(de)(de)影響,當機(ji)床運行(xing)的(de)(de)(de)速度(du)(du)在溫(wen)度(du)(du)上升而呈(cheng)(cheng)現降(jiang)低狀(zhuang)態(tai)時,便會使加工(gong)生產零(ling)件的(de)(de)(de)精(jing)度(du)(du)及質量受到很大程(cheng)度(du)(du)的(de)(de)(de)影響。
在上(shang)述分析過(guo)程中,認(ren)識到(dao)機(ji)械加工(gong)(gong)工(gong)(gong)藝會對零件加工(gong)(gong)精度產生多方面的影(ying)響(xiang)。為了提高零件加工(gong)(gong)精度,有必要采(cai)取(qu)行之有效(xiao)的控制策略。具(ju)體(ti)策略如下:
3.1 對零件(jian)制造(zao)過程加以嚴格控制
基于(yu)(yu)機械(xie)(xie)加工工藝應用期間(jian),要(yao)(yao)使(shi)幾何(he)精(jing)度(du)誤(wu)(wu)(wu)差對(dui)零(ling)件精(jing)度(du)造(zao)成的(de)影響得到有效(xiao)控制,便需(xu)要(yao)(yao)優化(hua)選取加工機械(xie)(xie)設(she)備(bei)(bei)(bei)。對(dui)于(yu)(yu)幾何(he)誤(wu)(wu)(wu)差來說,通常出自于(yu)(yu)出廠時的(de)機械(xie)(xie)加工設(she)備(bei)(bei)(bei)當中,因此(ci)有必要(yao)(yao)嚴格(ge)檢查所需(xu)的(de)機械(xie)(xie)加工設(she)備(bei)(bei)(bei)。基于(yu)(yu)檢查期間(jian),對(dui)設(she)備(bei)(bei)(bei)自身潛(qian)在的(de)誤(wu)(wu)(wu)差問題加以掌握,通過優化(hua)選取符合生產高精(jing)度(du)零(ling)件的(de)機械(xie)(xie)加工設(she)備(bei)(bei)(bei)。針對(dui)已經投(tou)入生產的(de)機械(xie)(xie)加工設(she)備(bei)(bei)(bei),進行排(pai)出,積灰(hui)情況相對(dui)臥式(shi)鍋(guo)爐較為嚴重。受熱面管(guan)束(shu)均采(cai)用蛇(she)形管(guan)形式(shi)。由于(yu)(yu)蛇(she)形管(guan)結構彈性較強(qiang),受機械(xie)(xie)振打清(qing)灰(hui)時易于(yu)(yu)灰(hui)分的(de)脫落,而且(qie)不(bu)易產生疲勞(lao)破(po)壞。
2.3 廢氣溫度及(ji)清灰裝置的影響
有研(yan)究表明,水(shui)泥生料(liao)在(zai)400℃以(yi)下呈松散狀態(tai),附(fu)著在(zai)受(shou)(shou)熱(re)面(mian)上(shang)的(de)(de)灰(hui)(hui)(hui)(hui)分比較(jiao)(jiao)容易去(qu)除(chu),在(zai)400~600℃會(hui)產(chan)生較(jiao)(jiao)弱的(de)(de)粘結性(xing)(xing),附(fu)著力較(jiao)(jiao)弱,也可(ke)以(yi)通過振打清(qing)除(chu),但溫(wen)度(du)更高時,水(shui)泥生料(liao)灰(hui)(hui)(hui)(hui)會(hui)產(chan)生較(jiao)(jiao)強(qiang)的(de)(de)粘接性(xing)(xing),通過機(ji)械振打不(bu)能完全清(qing)除(chu)。純低溫(wen)窯(yao)尾余熱(re)鍋爐(lu)的(de)(de)廢氣溫(wen)度(du)一般在(zai)400℃以(yi)下,少量生產(chan)線可(ke)能達到400℃以(yi)上(shang)。因此窯(yao)尾余熱(re)鍋爐(lu)主要采用機(ji)械振打裝置進行清(qing)灰(hui)(hui)(hui)(hui),振打清(qing)灰(hui)(hui)(hui)(hui)的(de)(de)主要優點(dian)是(shi)(shi)清(qing)灰(hui)(hui)(hui)(hui)頻率高,由于(yu)(yu)窯(yao)尾受(shou)(shou)熱(re)面(mian)積灰(hui)(hui)(hui)(hui)速度(du)很快,如果清(qing)灰(hui)(hui)(hui)(hui)間(jian)隔(ge)過長(chang),受(shou)(shou)熱(re)面(mian)上(shang)的(de)(de)平均積灰(hui)(hui)(hui)(hui)厚(hou)度(du)較(jiao)(jiao)大(da),換熱(re)效果就會(hui)長(chang)時間(jian)處于(yu)(yu)較(jiao)(jiao)差(cha)的(de)(de)狀態(tai),而機(ji)械振打的(de)(de)清(qing)灰(hui)(hui)(hui)(hui)周(zhou)期短,因此清(qing)灰(hui)(hui)(hui)(hui)效果好(hao),另(ling)外其還有工(gong)作可(ke)靠(kao),投資較(jiao)(jiao)小,消(xiao)耗動力少,不(bu)會(hui)對(dui)煙(yan)氣增加額外的(de)(de)介(jie)質的(de)(de)優點(dian),缺點(dian)是(shi)(shi)可(ke)能對(dui)受(shou)(shou)壓元件及焊縫產(chan)生疲勞破(po)壞(huai),而窯(yao)尾余熱(re)鍋爐(lu)采用彈性(xing)(xing)較(jiao)(jiao)強(qiang)的(de)(de)蛇形(xing)管束,較(jiao)(jiao)好(hao)的(de)(de)避免了(le)這種情(qing)況。
目前本地區在用(yong)的(de)(de)(de)窯尾(wei)余(yu)熱鍋(guo)(guo)爐(lu)全部采用(yong)機(ji)械(xie)振打(da)清(qing)灰(hui),從鍋(guo)(guo)爐(lu)檢修和定期檢驗的(de)(de)(de)情(qing)(qing)況(kuang)(kuang)(kuang)來看,使用(yong)機(ji)械(xie)振打(da)清(qing)灰(hui)基(ji)本能夠滿足窯尾(wei)余(yu)熱鍋(guo)(guo)爐(lu)的(de)(de)(de)清(qing)灰(hui)需要,大部分(fen)鍋(guo)(guo)爐(lu)的(de)(de)(de)積灰(hui)情(qing)(qing)況(kuang)(kuang)(kuang)良(liang)好,但有(you)少量鍋(guo)(guo)爐(lu)的(de)(de)(de)受(shou)熱面管(guan)束出現了積灰(hui)較(jiao)嚴重(zhong),在受(shou)熱面始段和末段管(guan)子間搭橋堆積的(de)(de)(de)情(qing)(qing)況(kuang)(kuang)(kuang)。這類情(qing)(qing)況(kuang)(kuang)(kuang)可(ke)能與管(guan)排間距(ju),廢氣流速,含塵量,振打(da)頻率,振打(da)力度(du)等因素(su)有(you)關(guan),具體原因還需進一步分(fen)析和研究。
3.1 氣流速(su)度的影響
余熱(re)鍋爐廢氣通過受(shou)(shou)熱(re)面(mian)時(shi)的(de)流(liu)速對積灰(hui)有較(jiao)大影響,氣流(liu)速度(du)(du)大,積灰(hui)容易被氣流(liu)帶走,而不易堆積在受(shou)(shou)熱(re)面(mian)上,但(dan)氣流(liu)速度(du)(du)大,對受(shou)(shou)熱(re)面(mian)管子的(de)磨損也會加劇,因此氣流(liu)速度(du)(du)應該控制(zhi)在一個(ge)合理的(de)范圍內。
3.2 管子排(pai)列方式和節(jie)距的(de)影響
廢氣(qi)通過錯列布(bu)置(zhi)(zhi)(zhi)的(de)管(guan)子(zi)(zi)(zi)時(shi),氣(qi)流擾動較大,容(rong)易帶走受(shou)熱面上的(de)積灰(hui),但由于錯列布(bu)置(zhi)(zhi)(zhi)的(de)管(guan)子(zi)(zi)(zi)相比(bi)順(shun)列布(bu)置(zhi)(zhi)(zhi)的(de)管(guan)子(zi)(zi)(zi)節(jie)(jie)距更小,更容(rong)易在管(guan)子(zi)(zi)(zi)之間形(xing)成積灰(hui)搭(da)橋堆(dui)積的(de)現(xian)象(xiang)。因此設計管(guan)子(zi)(zi)(zi)排列方(fang)式和(he)節(jie)(jie)距時(shi)應綜合考慮(lv)兩方(fang)面因素的(de)影響(xiang)。目前窯(yao)頭鍋(guo)爐多采用(yong)錯列布(bu)置(zhi)(zhi)(zhi),窯(yao)尾鍋(guo)爐多采用(yong)順(shun)列布(bu)置(zhi)(zhi)(zhi)。