Kufanele Usebenzise Nini I-Metal Bellow Mechanical Seal?

Isikhathi Sokukhetha I-Metal Bellows Mechanical Seal

Izivalo zensimbi ezisebenzisa imishini zimelela ikhambi elibalulekile lobunjiniyela bokujikeleza imishini esebenza ngaphandle kwemingcele ejwayelekile yezivalo zendabuko ezisekelwe ku-elastomer. Ngokushintsha isivalo sesibili esinamandla kanye neziphethu eziningi zekhoyili nge-welded metallic bellows core, lezi zivalo zinikeza amandla entwasahlobo adingekayo okulayisha ubuso kanye nomngcele wokuvala wesibili ongavali. Lo mklamo okhethekile ushintsha ngokuyisisekelo imikhawulo yokusebenza yephampu, okuvumela ukusebenza okuqhubekayo ezindaweni ezizowohloza ngokushesha izindlela zokuvala ezijwayelekile.

Izinga Lokushisa, Ingcindezi, kanye Nesivinini Somgodi

Onjiniyela bavame ukushintshela kuma-bellow ensimbi lapho imingcele yenqubo idlula imikhawulo yokusebenza ephephile yama-O-rings ajwayelekile. I-bellows seal yensimbi ejwayelekile ene-single-ply edge-welded metal seal iphatha kahle amazinga okushisa okusebenza asukela ku--75°C kuya ku-400°C (-100°F kuya ku-750°F), idlula kakhulu imikhawulo evamile yokushisa engu-150°C kuya ku-200°C yama-elastomers e-Viton noma e-Kalrez. Ezisetshenzisweni ze-cryogenic ezisingatha amagesi ancibilikisiwe, isakhiwo sensimbi sigcina ukuguquguquka kwaso lapho irabha izophuka khona futhi iqhekeke.

Amakhono okucindezela aqinile ngokulinganayo. Nakuba ama-bellows ajwayelekile ahlanganiswe ngomphetho asebenza ngokuthembeka kuze kufike ku-20 bar (290 psi), ama-bellows akhethekile ane-ply noma i-hydroformed angamelana nokucindezeleka okungaphezu kwe-69 bar (1,000 psi). Ngaphezu kwalokho, lawa ma-seal agcina ukulandelela ubuso okuzinzile ngesivinini somshaft esifinyelela kumamitha angu-25 ngomzuzwana (amamitha angu-5,000 ngomzuzu), okwenza afaneleke kakhuluamaphampu e-centrifugal asheshayongokufuna izinto eziningiizinqubo zezimboni.

Ukuhambisana Kwamakhemikhali, Izinto Eziqinile, Nokuhlanzeka

Isimo esingaguquki sesivalo sesibili ekwakhiweni kwe-bellows sixazulula inkinga yokulengiswa kwe-elastomer—imodi yokuhluleka okuyinhloko ezivalweni zokucindezela lapho i-O-ring inamathela khona emgodleni ngenxa yokuwohloka kwamakhemikhali noma ukungcola kwendawo. Lokhu kwenza i-metal bellows ifaneleke kahle kakhulu uketshezi olunolaka olukhulu lwamakhemikhali, okuhlanganisa ama-acid aqinile, izinyibilikisi, kanye nezixazululo ze-caustic ezihlasela amakhemikhali e-organic.

Uma usebenzisana nezinhlayiya ezigcwele izinhlayiya noma ama-slurries aqukethe izinto eziqinile ezifika ku-10% ngesisindo, imiklamo ye-bellows ejikelezayo isebenzisa amandla e-centrifugal ukuze ilahle njalo izinhlayiya kude ne-convolutions, ivimbele ukuvaleka. Kodwa-ke, ukuhlanzeka okuqinile ngesikhathi sokugeleza kwesistimu yokuqala kuyadingeka. Noma yikuphi ukungcola kwensimbi okuqinile noma isikali sepayipi esiboshwe phakathi kwamapheshana e-bellows ahlukaniswe kahle ngesikhathi sokuqalisa kungavimbela ukunyakaza kwe-axial, kubangele ukugxila kokucindezeleka kwendawo, futhi kubangele ukwehluleka kokukhathala ngaphambi kwesikhathi.

Indlela I-Mechanical Seal Yensimbi Esebenza Ngayo

Indlela yokwakheka kwe-metal bellows seal ishintsha ngokuyisisekelo indlela ukulayisha ubuso kanye nokulinganisela kwe-hydraulic okufezwa ngayo ebhokisini lokufutha ipompo. Ngokungafani ne-pusher seals ezithembele eziphethwini ze-coil ezihlukile, iyunithi ye-continuous bellows isabalalisa umthwalo wentwasahlobo ngokulinganayo kuwo wonke ama-degree angu-360 ebusweni be-seal, okwenza ifilimu yoketshezi ibe ngcono phakathi kwezingxenye ezijikelezayo nezimile.

Ukusebenza Uma kuqhathaniswa Nezimbozo Zokucindezela

Lokhu kulayisha okufanayo kuthinta ngqo ukuzinza kwe-kinetic kobuso besivalo ngaphansi kwezimo ezihlukahlukene ze-hydraulic. Ukususwa kwe-elastomer eshelelayo kuyisici esibaluleke kakhulu lapho kuhlolwa ukusebenza.

Ngokususa i-O-ring enamandla, i-bellows seal iqeda ama-shaft fretting. Ama-fretting enzeka lapho ukunyakaza okuncane kwe-elastomer kudonsa isikhwama sepompo ngokuhamba kwesikhathi, okuholela ekushintsheni kwe-shaft ebizayo kanye nezindlela zokuvuza eziqhubekayo ngaphansi kwe-seal.

Ukuvuza, I-Torque, Nokuthembeka

Ukulinganisela kwe-hydraulic kuyingxenye yokwakheka kwezinsimbi zensimbi ezishiselwe ngomphetho, ezitholakala ngokubeka ububanzi obusebenzayo bezinsimbi maqondana nobuso besivalo. Lesi silinganiso sebhalansi esilungiselelwe kahle (esivame ukwakhiwa phakathi kuka-0.65 no-0.80) sinciphisa ukukhiqizwa kokushisa nokuguguleka kokungqubuzana, kunciphisa kakhulu amazinga okuvuza abe amazinga angabonakali ngaphansi kokusebenza okuvamile kwesimo esizinzile.

Ukudluliswa kwe-torque kuphathwa ngqo nge-bellows core noma nge-drive lugs ezikhethekile ekusetshenzisweni kokucindezela okuphezulu, okuqinisekisa ukuthi i-torque yokuqala ayiguquli futhi ayichebi amapheshana ensimbi. Ezisetshenzisweni zokuhlanza ezishisa kakhulu, ukufaka esikhundleni se-pusher seal ehlulekayo nge-metal bellows seal echazwe kahle kuvame ukwandisa i-Mean Time Between Failures (MTBF) kusukela ezinyangeni ezingu-8 kuya kwezingu-12 ezimbi ngokomlando kuya ezinyangeni ezingaphezu kuka-36, okuletha ukwanda okukhulu kokuthembeka kwemishini iyonke.

Izimo Zokusebenza Eziqinisekisa Ukusetshenziswa Kwayo

Ukukhetha uphawu lwensimbi olusebenzisa izinsimbi akuvamile ukuba yisinqumo esizenzakalelayo sokusetshenziswa kwamanzi angenangozi ngenxa yezindleko zalo zokuqala eziphezulu. Kunalokho, kuwukuthuthukiswa okunesu okusetshenziswayo lapho izindawo ezithile zokusebenza ezinonya zenza ukuthi izivalo zokucindezela zingabi namandla okusebenza ngomshini noma ngamakhemikhali.

Izinga Lokushisa Eliphezulu Neliphansi, Umshini Wokushaja, Nokugcotshwa Okubi

Izinga lokushisa eliphakeme yizona ezibangela ukucaciswa kwe-bellows. Ezisetshenzisweni ze-cryogenic ezisingatha i-nitrogen ewuketshezi noma i-LNG emazingeni okushisa afinyelela ku--196°C (-320°F), ama-elastomer ayahluleka ngokushesha. Ngokuphambene nalokho, ezinhlelweni zokudlulisa uketshezi lokushisa noma phansi kwefektri ezisebenza ngokuqhubekayo ku-350°C kuya ku-425°C, ama-elastomer e-organic ayancibilika noma ashise i-carbon. Ama-bellow ensimbi agcina izinga lawo eliqondile lentwasahlobo kanye nokuqina kokuvala kulo lonke lolu hlobo lokushisa.

Ngaphezu kwalokho, ekusetshenzisweni kwe-vacuum okudonsa phansi ku-0.1 bar absolute, noma izinhlelo ezihlushwa ukusebenza okomile ngezikhathi ezithile kanye nokugcotshwa okungekuhle, ukulayishwa kobuso okulungiselelwe kahle, okufanayo kwe-bellows kusiza ukugcina ifilimu yoketshezi ebalulekile. Lokhu kuvimbela umonakalo omkhulu wobuso kanye nokuqhekeka kokushisa okuvame ukwenzeka lapho uphawu lokucindezela lulahlekelwa yisithiyo salo sokugcoba.

Uketshezi Olubolayo, Ingozi Yokubhoboza, kanye Nokuhamba Kweshaft

Uketshezi olupholisha noma oluyi-coke lapho luchayeka emazingeni okushisa asemkhathini—njenge-hydrocarbon esindayo, i-asphalt, kanye ne-oyili engahluziwe—lubeka izingozi ezinkulu ezivalweni ezijwayelekile. Njengoba lokhu ketshezi luvuza ngokuncane kakhulu ebusweni be-seal futhi lupholile, lwakha ama-carbon deposits aqinile. Esivalweni sokusunduza, lokhu kupholisha kuvimbela i-O-ring enamandla, okubangela ukwehluleka okusheshayo kwe-seal. I-metal bellows seal, engenazo i-elastomers yesibili ezishelelayo, iyaqhubeka nokulandelela ubuso be-seal ngisho nalapho kwenzeka ukupholisha okulingene ohlangothini lomoya.

Ngaphezu kwalokho, izimbobo zingamela ukunyakaza okukhulu kwe-axial shaft—ngokuvamile kufika ku-+/- 2.0 mm—okubangelwa ukwanda kokushisa kwe-pump shaft ezinkonzweni zokushisa okuphezulu. Imunca lokhu kushintsha kobukhulu ngokugoba kwe-welded convolutions ngaphandle kokuphazamisa igebe lokuvala noma ukugoba kwe-shaft sleeve.

Imikhawulo, Izindlela Zokwehluleka, kanye Nezindlela Zokushintshana

Naphezu kwamandla azo aqinile, izivalo zensimbi zinemikhawulo yokusebenza ehlukile kanye nokushintshana. Imodi yokuhluleka okuyinhloko ukucheba okujikelezayo; uma uphawu luhlangana ngenxa yokwakheka kwekristalu yomkhiqizo ngesikhathi sokuvala iphampu, amandla okujikeleza lapho eqala angadabula ngokushesha izivalo ezihlanganisiwe.

Ngaphezu kwalokho, amapheshana amancane ensimbi (ngokuvamile angu-0.10 mm kuya ku-0.15 mm ubukhulu) asengozini enkulu yokukhathala ngenxa yokudlidliza kwemishini. Amazinga okudlidliza adlula i-4.5 mm/s i-RMS angabangela ukuzwakala kwe-harmonic, okuholela ekuqhekekeni okusheshayo kwe-weld. Okokugcina, ukusetshenziswa kwemali enkulu kuyinzuzo enkulu, lapho izivalo zensimbi ezifakwe onqenqemeni zivame ukudinga iprimiyamu yezindleko engu-1.5x kuya ku-3.0x kunezivalo ezijwayelekile ze-pusher, okudinga ukulungiswa okucacile kokubuyisela imali ekutshalweni kwezimali okusekelwe esikhathini eside sokusebenza.

Indlela Yokucacisa Nokufaka I-Metal Bellows Mechanical Seal

Ukufakwa ngempumelelo kwesivalo somshini sokubhoboza insimbi kuncike kakhulu ekucacisweni okuqinile kwezinto zokwakha kanye nemikhuba yokufaka enembile. Ngenxa yokuthi lezi zivalo zenzelwe isevisi enzima, i-metallurgy engaphansi kwekhwalithi noma ukuhambisana okungafanele kwemishini kuzosusa ngokushesha izinzuzo zazo zokusebenza ezingokwemvelo.

I-Metallurgy, Izinto Zobuso, kanye Nokucushwa Kwesivalo

Insimbi ye-bellows core kumele ifaniswe ngokucophelela noketshezi lwenqubo. Insimbi engagqwali ye-AM350 iyindinganiso yezicelo ezijwayelekile zokushisa okuphezulu, enikeza ukushibilika okuhle kakhulu kanye nokumelana nokukhathala. Ezindaweni ezigqwala kakhulu ezifaka ama-chloride noma igesi emuncu (H2S), onjiniyela bathuthukela ku-Alloy C-276 (Hastelloy) noma i-Alloy 718 (Inconel), ezinikeza ukumelana okuphezulu ekuqhekekeni nasekuqhekekeni kokugqwala okucindezelekile.

Inhlanganisela yobuso be-seal ivame ukuhlanganisa indandatho ye-Silicon Carbide (SiC) engashintshi nendandatho ye-Carbon Graphite ejikelezayo ukuze kube nokuthambisa okuhle. Kodwa-ke, izinsizakalo ezihudula kakhulu zingadinga ukubhanqa okuqinile njenge-SiC vs. Tungsten Carbide (TC). Ukucushwa kunqunywa yizindinganiso ze-API 682, kanye ne-Arrangement 1 (uphawu olulodwa) olusetshenziselwa uketshezi olujwayelekile lokushisa okuphezulu, kanye ne-Arrangement 2 noma 3 (uphawu oluphindwe kabili olungacindezelwanga noma olucindezelwe) olugunyazwe kuma-organic compounds ayingozi noma aguquguqukayo (ama-VOC).

Ukufakwa, Ukuqondanisa, Ukuqalisa, kanye Nokuqapha

Imiklamo ye-cartridge sealsezibe yindinganiso yemboni, zihlanganisa izimbobo, ubuso, kanye nepuleti le-gland zibe yiyunithi eyodwa, esethiwe kusengaphambili eqeda isidingo sokulinganisa ngesandla ku-pump shaft. Ngesikhathi sokufakwa, ukugijima komgodi we-pump kumele kuqinisekiswe ngokuqinile; ukufundwa kwe-total indicator (TIR) ​​akufanele kudlule u-0.05 mm (0.002 inches) ukuvimbela ukugoba ngokweqile nokungalingani kwe-bellows convolutions.

Izinqubo zokuqalisa izinhlelo zokusebenza ezisebenzisa izinga lokushisa eliphezulu zidinga isigaba sokulawula ukushisa kwangaphambi kwesikhathi, ngokuvamile kusetshenziswa i-API Plan 32 external flush noma i-API Plan 62 steam quench. I-pump casing kanye ne-seal chamber kumele kufudunyezwe ngesivinini esiphezulu esingu-50°C ngehora ukuvimbela ukushaqeka kokushisa ebusweni be-silicon carbide obuthambile. Ukuqapha okuqhubekayo kokushisa kwe-flush kanye ne-seal chamber pressure kubalulekile ukuqinisekisa ukuthi uketshezi luhlala okungenani ku-15°C ngaphansi kwengcindezi yalo yomhwamuko, kuvimbele ukukhanya nokusebenza okomile ebusweni be-seal.

Uhlaka Lwezinqumo Zokukhetha Isivalo

Ukushintshela esivalweni somshini esimbozwe ngensimbi kudinga ukuhlolwa okuhlelekile kwezimo zenqubo, umlando wokwehluleka, kanye nezindleko zomjikelezo wokuphila. Uhlaka lwesinqumo olujwayelekile luvumelaonjiniyela bokuthembeka kwezitshaloukuze kuqinisekiswe ukusetshenziswa kwemali mboleko ngendlela eqotho ngokulinganisa intengo yokuqala yokuthenga neyokonga kokusebenza kwesikhathi eside.

Uhlu Lokuhlola Lokufaka Isicelo

I-matrix elandelayo isebenza njengohlu lokuhlola oluyinhloko lokufaka isicelo ukuze kunqunywe ukuthi isivalo sensimbi esiqinile siyisisombululo sobuchwepheshe esidingekayo ohlelweni oluthile lokupompa.

Uma kuhlangatshezwana nanoma yimuphi umbandela owodwa kulolu hlu lokuhlola, imikhawulo yokuklama engokwemvelo yesivalo esijwayelekile sokucindezela cishe izoholela ekuhlulekeni kwangaphambi kwesikhathi, okwenza ukuklama kwe-bellows kube ukukhetha okuhle ngokobuchwepheshe nangokwezimali.

Ingozi, Ukuthobela Imithetho, Isikhathi Sokusebenza, kanye Nezindleko Zokufaka Esimweni Esisha

Ngaphandle kwemininingwane yobuchwepheshe, isinqumo kumele sihlanganise ukunciphisa ubungozi, ukuthobela imithetho yemvelo, kanye nesikhathi sokusebenza kwezitshalo sonke. Ezindaweni ezilawulwa yimithethonqubo eqinile yezemvelo, izivalo zensimbi ezifakwe emphethweni zidlala indima ebalulekile ekunciphiseni ukukhishwa kwegesi okubalekayo, zigcina amazinga okuvuza kwe-volatile organic compound (VOC) ngaphansi kakhulu komkhawulo wokulawula oqinile ongu-500 ppm ochazwe yi-EPA kanye nezinhlangano zomhlaba ezilinganayo.

Nakuba izindleko zangaphambili zekhatriji ye-bellows zingasukela ku-$2,500 kuya ku-$8,000 kuye ngokuthi insimbi ingakanani kanye nosayizi womgodi, ukuhlaziywa kwezezimali kumele kufake phakathi izindleko zesikhathi sokungasebenzi esigwenyiwe. Ezimbonini zenqubo eqhubekayo ezifana nokuhlanzwa kwephethiloli nomaukucubungula i-petrochemical, ukwehluleka okukodwa kwephampu kungabangela ukungasebenzi kahle kokukhiqiza okungaphezu kuka-$10,000 ngehora. Ngokususa ukuwohloka kwe-elastomer, ukuvimbela ukushaqeka kweshaft, kanye nokusinda ezinkathini zokushisa, uphawu lwensimbi oluthambile lunciphisa kakhulu imvamisa yokudilizwa kwephampu. Ekugcineni, uma lusetshenziswa ezindaweni ezifanele zesevisi esezingeni eliphezulu, izindleko eziphelele zobunikazi (TCO) zophawu lwensimbi oluthambile ziphansi kakhulu kunezophawu lwe-pusher esikhathini sokuphila kweminyaka emihlanu.

Izinto Ezibalulekile Okufanele Uzicabangele

• Iziphetho ezibaluleke kakhulu kanye nesizathu se-Metal Bellow Mechanical Seal
• Imininingwane, ukuhambisana, kanye nokuhlolwa kwengozi okufanele kuqinisekiswe ngaphambi kokuthi uzibophezele
• Izinyathelo ezilandelayo ezisebenzayo kanye nezixwayiso abafundi abangazisebenzisa ngokushesha

imibuzo ejwayelekile ukubuzwa

Kufanele ngikhethe nini uphawu lwensimbi olungaphansi komshini?

Sebenzisa lapho amaphampu ebhekene nokushisa okukhulu, amakhemikhali anamandla, isivinini esiphezulu somgodi, noma lapho izindandatho ze-elastomer O-rings zehluleka ngenxa yokumiswa noma ukukhathala.

Yiliphi izinga lokushisa elingasetshenziswa yinsimbi ukubopha uphawu lomshini?

Imiklamo evamile ehlanganisiwe ngomphetho owodwa iphatha cishe u-75°C kuya ku-400°C, okwenza ifanelekele izinsizakalo ze-cryogenic kanye nokushisa okuphezulu.

Ingabe izivalo zensimbi ezingaphansi komhlaba zingcono kumaphampu amakhemikhali kanye ne-solvent?

Yebo. I-static metallic secondary seal yazo igwema ukuhlaselwa yi-elastomer, ngakho-ke zisebenza kahle kuma-acid, izinyibilikisi, kanye nezinsizakalo ze-caustic.

Ingabe izivalo zensimbi ezingaphansi komshini zingasebenza emshinini ongcolile noma oqukethe izinto eziqinile?

Yebo, ikakhulukazi imiklamo ye-bellows ejikelezayo yemidiya enezinto eziqinile ezingafika ku-10%, kodwa ukuhlanza okusha kumele kususe imfucumfucu yensimbi kanye nesikali sepayipi.

Ingabe iVictor Seals ingahlinzeka ngezivalo zensimbi ezifakwe esikhundleni sezinhlobo zamaphampu e-OEM?

Yebo. I-Victor Seals inikeza izivalo ezihambisana ne-OEM nezingena esikhundleni sezinye zemikhiqizo efana ne-IMO, i-Alfa Laval, i-Grundfos, i-APV, i-Flygt, i-Fristam, i-Lowara, ne-Allweiler.