Ufanele Usebenzise Nini I-Metal Bellow Mechanical Seal?

Ixesha lokukhetha iTywina leMetal Bellows Mechanical

Izitywino zesinyithi ezisebenzisa i-mechanical bellows zimele isisombululo esibalulekileyo sobunjineli kwizixhobo ezijikelezayo ezisebenza ngaphandle kweeparamitha eziqhelekileyo zezitywino zemveli ezisebenzisa i-elastomer. Ngokutshintsha isitywino sesibini esitshintshayo kunye nezipringi ezininzi ze-coil ngesiseko se-metallic bellows esihlanganisiweyo, ezi zitywino zibonelela ngamandla entwasahlobo afunekayo kunye nomda wokutywina wesibini ongavaliyo. Olu lwakhiwo lukhethekileyo lutshintsha ngokusisiseko imida yokusebenza kwepompo, luvumela ukusebenza okuqhubekayo kwiindawo eziya kunciphisa ngokukhawuleza iindlela zokutywina ezisemgangathweni.

Ubushushu, Uxinzelelo, kunye nesantya seShaft

Iinjineli zihlala zitshintshela kwi-metal bellows xa iiparameter zenkqubo zigqitha imida yokusebenza ekhuselekileyo yee-O-rings eziqhelekileyo. I-standard single-ply edge-welded metal bellows seal iphatha kakuhle amaqondo obushushu okusebenza ukusuka kwi--75°C ukuya kwi-400°C (-100°F ukuya kwi-750°F), idlula kakhulu imida yobushushu eqhelekileyo ye-150°C ukuya kwi-200°C ye-Viton okanye i-Kalrez elastomers. Kwizicelo ze-cryogenic eziphatha iigesi ezinyibilikisiweyo, isakhiwo sesinyithi sigcina ukuguquguquka kwaso apho irabha iya kuba buthathaka kwaye iqhekeke.

Amandla oxinzelelo aqinile ngokulinganayo. Nangona ii-bellows ezisemgangathweni ezidityaniswe ngomphetho zisebenza ngokuthembekileyo ukuya kuthi ga kwi-20 bar (290 psi), ii-bellows ezikhethekileyo ze-multi-ply okanye ze-hydroformed zinokumelana noxinzelelo olungaphezulu kwe-69 bar (1,000 psi). Ngaphezu koko, ezi seals zigcina umkhondo wobuso ozinzileyo kwisantya somphezulu we-shaft ukuya kuthi ga kwi-25 yeemitha ngomzuzwana (5,000 iinyawo ngomzuzu), nto leyo eyenza ukuba zifaneleke kakhuluiimpompo ze-centrifugal ezikhawulezayongokufuna izinto ezininziiinkqubo zoshishino.

Ukuhambelana kweekhemikhali, izinto eziqinileyo, kunye nococeko

Indlela engaguqukiyo yesitywina sesibini kuyilo lwe-bellows ngokwemvelo isombulula ingxaki yokuxhonywa kwe-elastomer—indlela yokusilela okuphambili kwii-pusher seals apho i-O-ring inamathela kwi-shaft ngenxa yokuwohloka kweekhemikhali okanye ukungcoliswa kwendawo. Oku kwenza ii-metal bellows zilungele kakhulu ulwelo olune-chemical aggressiveness ephezulu, kuquka ii-asidi ezinamandla, izinyibilikisi, kunye nezisombululo ze-caustic ezihlasela ii-organic compounds.

Xa usebenza ngezinto ezigcwele iinxalenye okanye amaqhekeza aqulethe izinto eziqinileyo ukuya kuthi ga kwi-10% ngobunzima, uyilo lwe-bellows olujikelezayo lusebenzisa amandla e-centrifugal ukulahla rhoqo iinxalenye kude nee-convolutions, nto leyo ethintela ukuvaleka. Nangona kunjalo, ucoceko oluqinileyo ngexesha lokuhla kwenkqubo yokuqala luyafuneka. Naluphi na uthuli oluqinileyo lwesinyithi okanye isikali sepayipi esibambeke phakathi kweencwadana ze-bellows ezixineneyo ngexesha lokuqalisa zinokuthintela intshukumo ye-axial, zibangele uxinzelelo lwendawo, kwaye zibangele ukungaphumeleli kokudinwa kwangaphambi kwexesha.

Indlela iMetal Bellows Mechanical Seal esebenza ngayo

Indlela yokwakheka kwe-metal bellows seal itshintsha ngokusisiseko indlela ukulayisha ubuso kunye nokulinganisela kwe-hydraulic okufezekiswa ngayo kwibhokisi yokufunxa ipompo. Ngokungafaniyo ne-pusher seals ezixhomekeke kwi-discrete coil springs, i-continuous bellows unit isasaza umthwalo we-spring ngokulinganayo kwi-360 degrees yobuso be-seal, iphucula ifilimu yolwelo phakathi kwezinto ezijikelezayo nezimiyo.

Ukusebenza Xa kuthelekiswa neePusher Seals

Olu xinzelelo olufanayo luchaphazela ngokuthe ngqo ukuzinza kwe-kinetic kwe-seal ubuso phantsi kweemeko ezahlukeneyo ze-hydraulic. Ukususwa kwe-sliding elastomer yeyona nto ibalulekileyo xa kuvavanywa ukusebenza.

Ngokususa i-O-ring enamandla, i-bellows seal iyayisusa i-shaft fretting. I-Fretting yenzeka xa ii-micro-moves ze-elastomer zikhupha i-pump sleeve ngokuhamba kwexesha, nto leyo ekhokelela ekutshintsheni i-shaft ebiza kakhulu kunye neendlela zokuvuza eziqhubekayo phantsi kwe-seal.

Ukuvuza, iTorque, kunye nokuthembeka

Ukulinganisela nge-hydraulic kuyinxalenye yoyilo lwe-bellows zesinyithi ezidityaniswe ngomphetho, ezifezekiswa ngokubeka ububanzi obusebenzayo be-bellows ngokunxulumene nobuso besitywino. Olu linganiselo lwebhalansi olulungisiweyo (oluhlala luyilwe phakathi kwe-0.65 kunye ne-0.80) lunciphisa ukuveliswa kobushushu kunye nokuguguleka kokungqubana, okunciphisa kakhulu amazinga okuvuza ukuya kumanqanaba angabonakaliyo phantsi kokusebenza okuqhelekileyo okuzinzileyo.

Ukuhanjiswa kwe-torque kuphathwa ngokuthe ngqo nge-bellows core okanye nge-drive lugs ezikhethekileyo kwizicelo zoxinzelelo oluphezulu, ukuqinisekisa ukuba i-startup torque ayijiki kwaye ayichebi amaphecana esinyithi. Kwizicelo zokucoca ezishushu kakhulu, ukutshintsha i-pusher seal engasebenziyo nge-metal bellows seal echazwe ngokufanelekileyo kudla ngokwandisa i-Mean Time Between Failures (MTBF) ukusuka kwiinyanga ezi-8 ukuya kwezi-12 ezimbi ngokwembali ukuya kwiinyanga ezingaphezulu kwama-36, okubonelela ngokwanda okukhulu ekuthembekeni kwezixhobo ngokubanzi.

Iimeko Zokusebenza Eziqinisekisa Ukusetyenziswa Kwayo

Ukukhetha isitywini sentsimbi esingenazintsimbi akulula ukukhetha ukusetyenziswa kwamanzi angenabungozi ngenxa yeendleko zayo zokuqala eziphezulu. Kunoko, kukuphucula okucwangcisiweyo xa iindawo ezithile zokusebenza ezinobundlobongela zenza ukuba izitywini ezityhalwayo zingasebenzi kakuhle ngoomatshini okanye ngamakhemikhali.

Ubushushu obuphezulu nobuphantsi, iVacuum, kunye nokuthambisa okubi

Ii-thermal extreme zezona zinto ziphambili ezibangela ukuba kubekho iinkcukacha ze-bellows. Kwii-cryogenic applications ezisebenzisa i-nitrogen engamanzi okanye i-LNG kumaqondo obushushu aphantsi ukuya kwi--196°C (-320°F), ii-elastomers ziyasilela ngoko nangoko. Ngokwahlukileyo koko, kwiinkqubo zokudlulisa ubushushu okanye kwiindawo zokucoca ezisebenza ngokuqhubekayo kwi-350°C ukuya kwi-425°C, ii-organic elastomers ziyanyibilika okanye zikhabhonize. Ii-metal bellows zigcina izinga lazo elichanekileyo lentwasahlobo yoomatshini kunye nokuqina kokutywina kulo lonke eli candelo lobushushu.

Ngaphezu koko, kwiinkqubo ze-vacuum ezitsalela phantsi kwi-0.1 bar absolute, okanye iinkqubo ezinengxaki yokuphuma komoya okomileyo kunye nokuthambisa okungekho semgangathweni, ukulayishwa kobuso okulungiselelweyo, okufanayo kwe-bellows kunceda ukugcina ifilimu yolwelo olubalulekileyo. Oku kuthintela umonakalo omkhulu wobuso kunye nokuqhekeka kobushushu okuhlala kwenzeka xa isitywina sokutyhala silahlekelwa ngumqobo waso wokuthambisa.

Ulwelo Oludlakazayo, Umngcipheko Wokucola, kunye Nokuhamba Kweshaft

Ulwelo olupholisha okanye olucola xa luchaphazeleka kumaqondo obushushu omoya—njengee-hydrocarbons ezinzima, i-asphalt, kunye ne-oyile ekrwada—lubeka umngcipheko omkhulu kwizitywini eziqhelekileyo. Njengoko ezi zinyibiliki zivuza ngemicroscope ebusweni bezitywini kwaye zipholile, zenza iidiphozithi zekhabhoni eziqinileyo. Kwisitywini sokutyhala, oku kucola kuyayithintela i-O-ring enamandla, okubangela ukungaphumeleli kwesitywini ngoko nangoko. Isitywini sentsimbi, esingenazo ii-elastomers zesibini ezityibilikayo, siyaqhubeka nokulandelela ubuso besitywini nokuba kucola okuphakathi kwenzeka kwicala lomoya.

Ukongeza, ii-bellows zinokukwazi ukwamkela intshukumo enkulu ye-axial shaft—edla ngokufikelela kwi-+/- 2.0 mm—ebangelwa kukwanda kobushushu be-pump shaft kwiinkonzo zobushushu obuphezulu. Ifunxa olu tshintsho lobukhulu ngokugoba kwe-welded convolutions ngaphandle kokuphazamisa umsantsa wokutywina okanye ukurhawuzelela i-shaft sleeve.

Imida, Iindlela zokungaphumeleli, kunye neeNguqulelo

Nangona zinamandla, izitywini zentsimbi zinemida eyahlukeneyo yokusebenza kunye nokutshintshana. Indlela yokusilela ephambili kukucheba nge-torsional; ukuba isitywini sijongana sinamathelana ngenxa yokwakheka kwemveliso ngexesha lokucima kwepompo, amandla okujikeleza xa uqalisa anokuyikrazula ngoko nangoko imibhobho edibeneyo.

Ukongeza, amaphetshana amancinci esinyithi (ngokwesiqhelo ubukhulu obuyi-0.10 mm ukuya kwi-0.15 mm) achaphazeleka kakhulu kukudinwa okubangelwa kukungcangcazela kwezixhobo. Amanqanaba okungcangcazela adlula i-4.5 mm/s RMS anokubangela i-harmonic resonance, nto leyo ekhokelela ekuqhekekeni kwe-weld ngokukhawuleza. Okokugqibela, inkcitho yemali yintengiselwano ebalulekileyo, kunye namatywina esinyithi adibeneyo adityaniswe ngomphetho adla ngokufuna iprimiyamu yexabiso eliyi-1.5x ukuya kwi-3.0x ngaphezu kwamatywina aqhelekileyo okutyhala, nto leyo edinga ukuqinisekiswa okucacileyo kwembuyekezo yotyalo-mali ngokusekelwe kwixesha elongezelelweyo lokusebenza.

Indlela yokuchaza nokufaka iTywina leMetal Bellows Mechanical

Ukuphunyezwa ngempumelelo kwesitywino soomatshini esineentsimbi kuxhomekeke kakhulu kwiinkcukacha ezingqongqo zezinto ezisetyenzisiweyo kunye neendlela zokufakela ezichanekileyo. Ngenxa yokuba ezi tywino zenzelwe inkonzo enzima, i-metallurgy engafanelekanga okanye ukulungelelaniswa okungafanelekanga koomatshini kuya kunciphisa ngokukhawuleza iingenelo zazo zokusebenza.

Isinyithi, Izinto zoBuso, kunye nokuCwangciswa kweSeal

Isinyithi se-bellow core kufuneka sihambelane kakuhle nolwelo lwenkqubo. I-AM350 stainless steel yeyona isemgangathweni wokusetyenziswa kobushushu obuphezulu ngokubanzi, inikezela ngokukwazi ukuwelda kakuhle kunye nokumelana nokudinwa. Kwiindawo ezinobungozi kakhulu ezibandakanya ii-chloride okanye igesi emuncu (H2S), iinjineli ziphucula ziye kwi-Alloy C-276 (Hastelloy) okanye i-Alloy 718 (Inconel), ezibonelela ngokuxhathisa okuphezulu kwi-stress corrosion cracking kunye ne-pitting.

Iindidi zobuso beSeal zihlala zidibanisa iringi yeSilicon Carbide (SiC) engashukumiyo kunye neringi yeCarbon Graphite ejikelezayo enoxinano oluphezulu ukuze ikwazi ukuthambisa kakuhle. Nangona kunjalo, iinkonzo ezirhabaxa kakhulu zinokufuna ukudityaniswa okuqinileyo njengeSiC ngokuchasene neTungsten Carbide (TC). Uqwalaselo lulawulwa yimigangatho ye-API 682, kunye neArrangement 1 (isitywina esinye) esetyenziselwa ulwelo olusemgangathweni oluphezulu, kunye neArrangement 2 okanye 3 (izitywina ezimbini ezingaxinzelelwanga okanye ezixinzelelweyo) ezigunyazisiweyo kwiikhompawundi ze-organic ezinobungozi okanye eziguquguqukayo (ii-VOC).

Ukufakwa, Ukulungelelaniswa, Ukuqalisa, kunye nokuBek' esweni

Uyilo lwetywina lekhatrijiziye zaba ngumgangatho weshishini, zigquma ii-bellows, ubuso, kunye ne-gland plate kwiyunithi enye, ebekwe kwangaphambili esusa imfuneko yokulinganisa ngesandla kwi-pump shaft. Ngexesha lokufakwa, ukuqaliswa kwe-pump shaft kufuneka kuqinisekiswe ngokungqongqo; ukufundwa kwe-total indicator (TIR) ​​akufuneki kudlule kwi-0.05 mm (0.002 intshi) ukuthintela ukugoba okugqithisileyo nokungalingani kwe-bellows convolutions.

Iinkqubo zokuqalisa izicelo zobushushu obuphezulu ziyalela isigaba sokufudumeza esilawulwayo, kusetyenziswa i-API Plan 32 external flush okanye i-API Plan 62 steam quench. I-pump casing kunye ne-seal chamber kufuneka zifudunyezwe ngesantya esiphezulu se-50°C ngeyure ukuthintela ukutshayiswa kobushushu kwiindawo ze-silicon carbide ezibuthathaka. Ukubeka iliso rhoqo kubushushu be-flush kunye noxinzelelo lwe-seal chamber kubalulekile ukuqinisekisa ukuba ulwelo luhlala ubuncinane kwi-15°C ngaphantsi koxinzelelo lwayo lomphunga, ukuthintela ukutsha kunye nokuphuma okomileyo kwiindawo ze-seal.

Isakhelo seSigqibo soKhetho lweSitywina

Ukutshintshela kwi-mechanical seal yentsimbi kufuna uvavanyo olucwangcisiweyo lweemeko zenkqubo, imbali yokusilela, kunye neendleko zomjikelo wobomi zizonke. Isakhelo sesigqibo esimiselweyo sivumelaiinjineli zokuthembeka kwezityaloukuthethelela inkcitho yenkunzi ngokungakhethi cala ngokulinganisa ixabiso lokuqala lokuthenga ngokuthelekisa nelongelwe ixesha elide lokusebenza.

Uluhlu lokujonga izicelo

Le matrix ilandelayo isebenza njengoluhlu lokuhlola oluphambili lokufaka isicelo ukuze kuchongwe ukuba isitywino sentsimbi sisisombululo sobugcisa esifunekayo kwinkqubo ethile yokupompa.

Ukuba kukho naluphi na umlinganiselo omnye kolu luhlu lokutshekisha ofezekisiweyo, imida yoyilo oluqhelekileyo lwe-pusher seal inokukhokelela ekusileleni kwangethuba, nto leyo eyenza uyilo lwe-bellows lube lolona khetho lufanelekileyo kwezobuchwepheshe nakwezemali.

Umngcipheko, Ukuthobela, Ixesha Lokusebenza, kunye neendleko zokutshintsha

Ngaphaya kweenkcukacha zobugcisa, isigqibo kufuneka siquke ukunciphisa umngcipheko, ukuthotyelwa kokusingqongileyo, kunye nexesha lokusebenza kwezityalo ngokubanzi. Kwimimandla elawulwa yimithetho engqongqo yokusingqongileyo, izitywina zentsimbi ezifakwe emphethweni zidlala indima ebalulekileyo ekunciphiseni ukukhutshwa kwegesi okubalekayo, zigcina ngokuthembekileyo amazinga okuvuza kwe-volatious organic compound (VOC) angaphantsi kakhulu komlinganiselo oqinileyo wolawulo we-500 ppm ochazwe yi-EPA kunye nemibutho efanayo yehlabathi.

Nangona ixabiso lokuqala lekhatriji ye-bellows linokusukela kwi-$2,500 ukuya kwi-$8,000 kuxhomekeke kubungakanani besinyithi kunye nobungakanani beshaft, uhlalutyo lwezemali kufuneka luqwalasele iindleko zexesha lokungasebenzi elithintelweyo. Kwimisebenzi eqhubekayo efana nokucocwa kwepetroleum okanyeukucubungula i-petrochemical, ukusilela kwepompo enye kunokubangela iindleko zokungasebenzi kwemveliso ezidlula i-$10,000 ngeyure. Ngokususa ukubola kwe-elastomer, ukuthintela ukurhawuzelela kweshaft, kunye nokusinda kwiinguqu zobushushu, i-metal bellows seal inciphisa kakhulu ukuphindaphindeka kokuqhekeka kwepompo. Ekugqibeleni, xa isetyenziswa kwiindawo ezifanelekileyo zenkonzo egqithisileyo, ixabiso elipheleleyo lobunini (TCO) le-metal bellows seal liphantsi kakhulu kunelo le-pusher seal kwiminyaka emihlanu yobomi.

Izinto ezibalulekileyo ekufuneka ziqwalaselwe

• Izigqibo ezibalulekileyo kunye nesizathu seMetal Bellow Mechanical Seal
• Iinkcukacha, ukuthobela imithetho, kunye nokuhlolwa komngcipheko okufuneka kuqinisekiswe ngaphambi kokuba uzibophelele
• Amanyathelo alandelayo asebenzayo kunye nezilumkiso abafundi abanokuzisebenzisa ngoko nangoko

Imibuzo ebuzwa qho

Ndingayikhetha nini itywina yomatshini yentsimbi engaphantsi?

Yisebenzise xa iimpompo zijongene nobushushu obugqithisileyo, iikhemikhali ezirhabaxa, isantya esiphezulu seshaft, okanye xa ii-elastomer O-rings zingaphumeleli ngenxa yokuxhoma okanye ukurhawuzelela.

Ingaba intsimbi iyakwazi ukubamba isitywino somatshini ngentsimbi engaphantsi koluphi ubushushu?

Iidizayini eziqhelekileyo ezidityaniswe ngomphetho omnye zibamba malunga ne-75°C ukuya kwi-400°C, nto leyo eyenza ukuba zilungele iinkonzo ezisebenzisa ubushushu obuphezulu kunye nobushushu obuphezulu.

Ngaba izitywini zentsimbi ezingaphakathi zingcono kwiimpompo zamakhemikhali kunye nezesolvent?

Ewe. I-static metallic secondary seal yazo iyakuphepha ukuhlaselwa yi-elastomer, ngoko ke zisebenza kakuhle kwii-asidi, izinyibilikisi, kunye neenkonzo ze-caustic.

Ngaba izitywino zesinyithi ezingaphantsi koomatshini zingasebenza kwi-slurry okanye kwi-solid-containing media?

Ewe, ingakumbi uyilo lwe-bellows olujikelezayo lwe-media olune-10% yezinto eziqinileyo, kodwa ukuhlanjwa kwe-startup kufuneka kususe inkunkuma yesinyithi kunye nesikali sepayipi.

Ngaba iVictor Seals inokubonelela ngee-seal zesinyithi ezitshintshayo kwiimveliso zepompo ze-OEM?

Ewe. I-Victor Seals ibonelela ngezitywino ezihambelana ne-OEM nezitshintshayo kwiimpawu ezifana ne-IMO, i-Alfa Laval, i-Grundfos, i-APV, i-Flygt, i-Fristam, i-Lowara, kunye ne-Allweiler.