行唐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行唐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shi104型行唐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.介jie質zhi腐fu蝕shi。密mi封feng件jian和he流liu體ti之zhi間jian的de高gao速su運yun動dong導dao致zhi接jie觸chu表biao麵mian上shang的de微wei小xiao不bu均jun勻yun。當dang流liu體ti為wei腐fu蝕shi性xing介jie質zhi時shi
，會hui加jia速su密mi封feng接jie觸chu麵mian的de化hua學xue反fan應ying，有you時shi有you益yi，有you時shi有you害hai。如ru果guo形xing成cheng的de氧yang化hua層ceng被bei破po壞huai，就jiu會hui發fa生sheng腐fu蝕shi。磨mo損sun和he磨mo蝕shi交jiao替ti作zuo用yong對dui材cai料liao造zao成cheng的de損sun傷shang稱cheng為wei磨mo蝕shi。通tong常chang，磨mo損sun對dui行唐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)行唐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)jiushidianxingdelizi。yuanyinshijietouneidejiezhichuyutingzhizhuangtai，shidecanyufushifanyingdewuzhinanyijiarujietounei
，jietouneidefushichanwunanyixiangwaikuosan。suizhefushidejinxing
，jietouzhongdejiezhizaichengfennongduhePH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；duiyuchangqitingyongdebeng
，yingjishipaichujijudeyetideng。bukenengwanquanxiaochujiegoushangdechaju。suoyiyibancaiyongfanghuzhoucheng，keyizaimifengquananzhuangbuweipentunaifushicailiaolaifangzhi。
　　5.電化學腐蝕。事實上
，行唐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。就行唐機械密封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。