發布時間:2026-04-22 10:11:51 人氣:303964 來源:川工密封
1.整體腐蝕和局部腐蝕。綜合腐蝕,即與介質接觸的零件表麵發生均勻腐蝕,其特點是零件重量減輕,甚至完全腐蝕;失去力量;降低硬度。如1Cr18Ni9Ti不(bu)鏽(xiu)鋼(gang)製(zhi)成(cheng)的(de)多(duo)彈(dan)簧(huang),在(zai)稀(xi)硫(liu)酸(suan)中(zhong)使(shi)用(yong)會(hui)出(chu)現(xian)這(zhe)種(zhong)情(qing)況(kuang)。局(ju)部(bu)腐(fu)蝕(shi)可(ke)以(yi)簡(jian)單(dan)地(di)通(tong)過(guo)零(ling)件(jian)上(shang)的(de)腐(fu)蝕(shi)點(dian)和(he)孔(kong)來(lai)識(shi)別(bie)。局(ju)部(bu)腐(fu)蝕(shi)是(shi)多(duo)相(xiang)合(he)金(jin)中(zhong)的(de)某(mou)一(yi)相(xiang)或(huo)單(dan)相(xiang)固(gu)溶(rong)體(ti)中(zhong)的(de)某(mou)一(yi)元(yuan)素(su)被(bei)介(jie)質(zhi)選(xuan)擇(ze)性(xing)溶(rong)解(jie)的(de)腐(fu)蝕(shi)形(xing)式(shi)。如(ru)鈷(gu)基(ji)硬(ying)質(zhi)合(he)金(jin)在(zai)高(gao)溫(wen)強(qiang)堿(jian)條(tiao)件(jian)下(xia)使(shi)用(yong),粘(zhan)結(jie)相(xiang)金(jin)屬(shu)鈷(gu)容(rong)易(yi)被(bei)腐(fu)蝕(shi),硬(ying)質(zhi)相(xiang)碳(tan)化(hua)鎢(wu)骨(gu)架(jia)失(shi)去(qu)強(qiang)度(du),在(zai)機(ji)械(xie)力(li)的(de)作(zuo)用(yong)下(xia)導(dao)致(zhi)晶(jing)粒(li)剝(bo)落(luo)。作(zuo)為(wei)另(ling)一(yi)個(ge)例(li)子(zi),由(you)於(yu)遊(you)離(li)矽(gui)的(de)腐(fu)蝕(shi),反(fan)應(ying)燒(shao)結(jie)碳(tan)化(hua)矽(gui)的(de)表(biao)麵(mian)顯(xian)示(shi)麻(ma)點(dian)(PH>10時).
fushiduimifengjiandexingnengyouhendayingxiang。youyumifengbizhujidelingjiangengxiao,jingdugenggao,suoyitongchangxuanzebizhujimifengnaifushidecailiao。duiyuyujiezhizhijiejiechudemifengjian,kecankaoxiangguanfushishoucezhongdeshujuxuanzeheshidecailiao。raner,zhexieshujukenengyu錯那機械密封係統中使用的條件不一致,因為它們大多是靜態條件下的腐蝕數據,並且工藝流程中的介質包含雜質或二次化合物。經驗表明,壓力、溫度和滑動速度都會加速腐蝕。隨著溫度的升高,密封件的腐蝕速率呈指數增長。
zaichuliqiangfushixingliutishi,caiyongwaimifenghuoshuangduanmifengkeyizuidaxiandudijianshaofushiduimifengdeyingxiang,yinweitayugongyiliutijiechudelingjianshuliangzuishao。zheyeshizaiqiangfushitiaojianxiaxuanzemifengjiegouzuigulaodeyaolizhiyi。
2.應力腐蝕。應力腐蝕是金屬材料在應力作用下在腐蝕環境中的腐蝕現象。無論是外載荷還是殘餘應力,都會加劇腐蝕。奧氏體不鏽鋼、銅(tong)合(he)金(jin)等(deng)。容(rong)易(yi)產(chan)生(sheng)應(ying)力(li)腐(fu)蝕(shi)。在(zai)應(ying)力(li)腐(fu)蝕(shi)過(guo)程(cheng)中(zhong),一(yi)般(ban)在(zai)金(jin)屬(shu)表(biao)麵(mian)形(xing)成(cheng)選(xuan)擇(ze)性(xing)腐(fu)蝕(shi)槽(cao),然(ran)後(hou)繼(ji)續(xu)局(ju)部(bu)腐(fu)蝕(shi),最(zui)後(hou)在(zai)應(ying)力(li)作(zuo)用(yong)下(xia)從(cong)槽(cao)底(di)產(chan)生(sheng)裂(lie)紋(wen)。典(dian)型(xing)的(de)例(li)子(zi)是(shi)104型錯那機械密封的傳動套筒,由1Cr18Ni9Ti製zhi成cheng。在zai氨an水shui泵beng中zhong使shi用yong時shi,傳chuan動dong套tao筒tong的de傳chuan動dong耳er環huan最zui容rong易yi產chan生sheng應ying力li腐fu蝕shi裂lie紋wen,從cong而er損sun壞huai耳er環huan。所suo以yi把ba凹ao耳er釘ding換huan成cheng實shi心xin耳er片pian可ke以yi防fang止zhi這zhe種zhong應ying力li腐fu蝕shi。
3.jiezhifushi。mifengjianheliutizhijiandegaosuyundongdaozhijiechubiaomianshangdeweixiaobujunyun。dangliutiweifushixingjiezhishi,huijiasumifengjiechumiandehuaxuefanying,youshiyouyi,youshiyouhai。ruguoxingchengdeyanghuacengbeipohuai,jiuhuifashengfushi。mosunhemoshijiaotizuoyongduicailiaozaochengdesunshangchengweimoshi。tongchang,mosundui錯那機械密封的非主要部件造成的損壞,如彈簧座、推環、huanzuodeng。bingbunengxunsufanyingmifengxingnengdebianhua,danqueshimocafushixiaodezhuyaoxingshizhiyi。yinci,zaiqiangtidefushijiezhizhong,mocafuyingyounaifushixinghaodecailiaozhicheng。liru,shiyong99.5%高純度氧化鋁陶瓷或不含遊離矽的熱壓燒結碳化矽。
4.間(jian)隙(xi)腐(fu)蝕(shi)。當(dang)介(jie)質(zhi)處(chu)於(yu)金(jin)屬(shu)與(yu)金(jin)屬(shu)或(huo)非(fei)金(jin)屬(shu)構(gou)件(jian)之(zhi)間(jian),且(qie)存(cun)在(zai)小(xiao)間(jian)隙(xi)時(shi),由(you)於(yu)介(jie)質(zhi)處(chu)於(yu)停(ting)滯(zhi)狀(zhuang)態(tai),間(jian)隙(xi)內(nei)金(jin)屬(shu)的(de)腐(fu)蝕(shi)會(hui)加(jia)速(su),這(zhe)種(zhong)現(xian)象(xiang)稱(cheng)為(wei)間(jian)隙(xi)腐(fu)蝕(shi)。例(li)如(ru)錯那機械密封彈簧座與軸之間的溝槽或衝蝕點,補償環輔助密封環與軸之間的溝槽或衝蝕點(這裏當然有微動磨損)就jiu是shi典dian型xing的de例li子zi。原yuan因yin是shi接jie頭tou內nei的de介jie質zhi處chu於yu停ting滯zhi狀zhuang態tai,使shi得de參can與yu腐fu蝕shi反fan應ying的de物wu質zhi難nan以yi加jia入ru接jie頭tou內nei,接jie頭tou內nei的de腐fu蝕shi產chan物wu難nan以yi向xiang外wai擴kuo散san。隨sui著zhe腐fu蝕shi的de進jin行xing,接jie頭tou中zhong的de介jie質zhi在zai成cheng分fen濃nong度du和hePH值zhi上shang與yu整zheng個ge介jie質zhi越yue來lai越yue不bu同tong,導dao致zhi接jie頭tou中zhong金jin屬shu表biao麵mian的de腐fu蝕shi加jia劇ju。間jian隙xi腐fu蝕shi對dui密mi封feng性xing能neng非fei常chang有you害hai。密mi封feng圈quan與yu雙shuang軸zhou之zhi間jian的de凹ao槽cao會hui導dao致zhi補bu償chang環huan無wu法fa軸zhou向xiang位wei移yi,失shi去qu隨sui動dong性xing,導dao致zhi端duan麵mian分fen離li和he泄xie漏lou。間jian隙xi腐fu蝕shi通tong常chang可ke以yi通tong過guo適shi當dang的de材cai料liao選xuan擇ze和he合he理li的de結jie構gou設she計ji來lai緩huan解jie。比bi如ru選xuan擇ze抗kang間jian隙xi腐fu蝕shi性xing能neng好hao的de材cai料liao;在(zai)結(jie)構(gou)設(she)計(ji)中(zhong),應(ying)盡(jin)可(ke)能(neng)避(bi)免(mian)液(ye)體(ti)積(ji)聚(ju)的(de)間(jian)隙(xi)和(he)死(si)區(qu)。采(cai)用(yong)自(zi)衝(chong)洗(xi)循(xun)環(huan),使(shi)密(mi)封(feng)腔(qiang)內(nei)的(de)介(jie)質(zhi)處(chu)於(yu)不(bu)斷(duan)更(geng)換(huan)和(he)流(liu)動(dong)的(de)狀(zhuang)態(tai),防(fang)止(zhi)介(jie)質(zhi)成(cheng)分(fen)的(de)濃(nong)度(du)變(bian)化(hua);對(dui)於(yu)長(chang)期(qi)停(ting)用(yong)的(de)泵(beng),應(ying)及(ji)時(shi)排(pai)出(chu)積(ji)聚(ju)的(de)液(ye)體(ti)等(deng)。不(bu)可(ke)能(neng)完(wan)全(quan)消(xiao)除(chu)結(jie)構(gou)上(shang)的(de)差(cha)距(ju)。所(suo)以(yi)一(yi)般(ban)采(cai)用(yong)防(fang)護(hu)軸(zhou)承(cheng),可(ke)以(yi)在(zai)密(mi)封(feng)圈(quan)安(an)裝(zhuang)部(bu)位(wei)噴(pen)塗(tu)耐(nai)腐(fu)蝕(shi)材(cai)料(liao)來(lai)防(fang)止(zhi)。
5.電化學腐蝕。事實上,錯那機械密封的各種腐蝕形式或多或少都與銅的電化學腐蝕有關。就錯那機械密封mocafueryan,tamenjingchangshoudaodianhuaxuefushidesunhai,yinweimocafuzhongtongchangshiyongbutongdecailiao。dangtamenchuyudianjiezhirongyezhongshi,butongcailiaojiechushihuichuxiandianouhexiaoying,jiyizhongcailiaodefushidedaocujin,lingyizhongcailiaodefushidedaoyizhi。liru,dangtongheniegegangyongyuyanghuajiezhishi,niegegangbeidianlihefenjie。yanshui、海水、稀鹽酸、稀硫酸等。都是典型的電解質溶液,密封件容易發生電化學腐蝕。所以最好選擇材料或者電位相近的陶瓷,以及玻璃纖維填充的PTFE。