發布時間:2026-04-23 19:46:29 人氣:304642 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)富陽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。
在zai處chu理li強qiang腐fu蝕shi性xing流liu體ti時shi,采cai用yong外wai密mi封feng或huo雙shuang端duan密mi封feng可ke以yi最zui大da限xian度du地di減jian少shao腐fu蝕shi對dui密mi封feng的de影ying響xiang,因yin為wei它ta與yu工gong藝yi流liu體ti接jie觸chu的de零ling件jian數shu量liang最zui少shao。這zhe也ye是shi在zai強qiang腐fu蝕shi條tiao件jian下xia選xuan擇ze密mi封feng結jie構gou最zui古gu老lao的de窯yao理li之zhi一yi。
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型富陽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富陽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富陽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;duiyuchangqitingyongdebeng,yingjishipaichujijudeyetideng。bukenengwanquanxiaochujiegoushangdechaju。suoyiyibancaiyongfanghuzhoucheng,keyizaimifengquananzhuangbuweipentunaifushicailiaolaifangzhi。
5.電化學腐蝕。事實上,富陽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。就富陽機械密封摩mo擦ca副fu而er言yan,它ta們men經jing常chang受shou到dao電dian化hua學xue腐fu蝕shi的de損sun害hai,因yin為wei摩mo擦ca副fu中zhong通tong常chang使shi用yong不bu同tong的de材cai料liao。當dang它ta們men處chu於yu電dian解jie質zhi溶rong液ye中zhong時shi,不bu同tong材cai料liao接jie觸chu時shi會hui出chu現xian點dian耦ou合he效xiao應ying,即ji一yi種zhong材cai料liao的de腐fu蝕shi得de到dao促cu進jin,另ling一yi種zhong材cai料liao的de腐fu蝕shi得de到dao抑yi製zhi。例li如ru,當dang銅tong和he鎳nie鉻ge鋼gang用yong於yu氧yang化hua介jie質zhi時shi,鎳nie鎘ge鋼gang被bei電dian離li和he分fen解jie。鹽yan水shui、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。