白雲機械密封的腐蝕類型

　　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1Cr18Ni9Tibuxiugangzhichengdeduodanhuang，zaixiliusuanzhongshiyonghuichuxianzhezhongqingkuang。jubufushikeyijiandanditongguolingjianshangdefushidianhekonglaishibie。jubufushishiduoxianghejinzhongdemouyixianghuodanxianggurongtizhongdemouyiyuansubeijiezhixuanzexingrongjiedefushixingshi。rugujiyingzhihejinzaigaowenqiangjiantiaojianxiashiyong
，zhanjiexiangjinshugurongyibeifushi，yingzhixiangtanhuawugujiashiquqiangdu，zaijixielidezuoyongxiadaozhijingliboluo。zuoweilingyigelizi
，youyuyouliguidefushi，fanyingshaojietanhuaguidebiaomianxianshimadian(PH>10時).
　　腐(fu)蝕(shi)對(dui)密(mi)封(feng)件(jian)的(de)性(xing)能(neng)有(you)很(hen)大(da)影(ying)響(xiang)。由(you)於(yu)密(mi)封(feng)比(bi)主(zhu)機(ji)的(de)零(ling)件(jian)更(geng)小(xiao)
，精(jing)度(du)更(geng)高(gao)，所(suo)以(yi)通(tong)常(chang)選(xuan)擇(ze)比(bi)主(zhu)機(ji)密(mi)封(feng)耐(nai)腐(fu)蝕(shi)的(de)材(cai)料(liao)。對(dui)於(yu)與(yu)介(jie)質(zhi)直(zhi)接(jie)接(jie)觸(chu)的(de)密(mi)封(feng)件(jian)
，可(ke)參(can)考(kao)相(xiang)關(guan)腐(fu)蝕(shi)手(shou)冊(ce)中(zhong)的(de)數(shu)據(ju)選(xuan)擇(ze)合(he)適(shi)的(de)材(cai)料(liao)。然(ran)而(er)
，這(zhe)些(xie)數(shu)據(ju)可(ke)能(neng)與(yu)白雲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
、tonghejindeng。rongyichanshengyinglifushi。zaiyinglifushiguochengzhong，yibanzaijinshubiaomianxingchengxuanzexingfushicao
，ranhoujixujubufushi
，zuihouzaiyinglizuoyongxiacongcaodichanshengliewen。dianxingdelizishi104型白雲機械密封的傳動套筒
，由1Cr18Ni9Tizhicheng。zaianshuibengzhongshiyongshi
，chuandongtaotongdechuandongerhuanzuirongyichanshengyinglifushiliewen，congersunhuaierhuan。suoyibaaoerdinghuanchengshixinerpiankeyifangzhizhezhongyinglifushi。
　　3.jiezhifushi。mifengjianheliutizhijiandegaosuyundongdaozhijiechubiaomianshangdeweixiaobujunyun。dangliutiweifushixingjiezhishi

，huijiasumifengjiechumiandehuaxuefanying

，youshiyouyi
，youshiyouhai。ruguoxingchengdeyanghuacengbeipohuai
，jiuhuifashengfushi。mosunhemoshijiaotizuoyongduicailiaozaochengdesunshangchengweimoshi。tongchang
，mosundui白雲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.jianxifushi。dangjiezhichuyujinshuyujinshuhuofeijinshugoujianzhijian，qiecunzaixiaojianxishi
，youyujiezhichuyutingzhizhuangtai，jianxineijinshudefushihuijiasu，zhezhongxianxiangchengweijianxifushi。liru白雲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；zaijiegoushejizhong

，yingjinkenengbimianyetijijudejianxihesiqu。caiyongzichongxixunhuan，shimifengqiangneidejiezhichuyubuduangenghuanheliudongdezhuangtai，fangzhijiezhichengfendenongdubianhua
；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
，白雲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。就白雲機械密封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。