I-Metal Bellow okanye i-Elastomer Bellow Seal: Indlela yokukhetha

Intshayelelo

Ukukhetha phakathi kwe-metal bellows seal kunye ne-elastomer bellows seal kuchaphazela okungaphezulu kakhulu kunokulingana okanye ixabiso: kugqiba ukuba ipompo iphatha kakuhle kangakanani ubushushu, ukuhlaselwa ngamakhemikhali, intshukumo yeshaft, kunye nexesha elide lenkonzo. Eli nqaku lichaza umahluko osebenzayo phakathi kwezi zakhiwo zimbini, kugxilwe apho i-metal bellows mechanical seal inika khona iingenelo ezicacileyo ngokususa amanqaku okusilela anxulumene ne-elastomer. Uza kufunda ukuba zeziphi iimeko zokusebenza ezikhetha ukhetho ngalunye, zeziphi iindlela zokusebenza onokuzilindela, kunye nendlela yokuvavanya ukuthembeka, iimfuno zolondolozo, kunye neendleko zobomi ngaphambi kokwenza ukhetho.

Indlela Yokuvavanya Itywina LeMetal Bellows Mechanical

Ukukhetha iteknoloji yokutywina echanekileyo sisigqibo sobunjineli esibalulekileyo esichaza ukuthembeka, ukhuseleko, kunye nokugcinwa kwezixhobo ezijikelezayo zoshishino. Embindini wesi sigqibo kukukhetha phakathi kwezitywina zemveli ezisekelwe kwi-elastomer kunyeisitywino soomatshini sentsimbiNangona ii-elastomers zisebenza ngokwaneleyo kwiindlela eziqhelekileyo, iindawo zoshishino ezinzima zifuna isisombululo esiqinileyo ngakumbi.

I-metal bellows seal ithatha indawo ye-dynamic secondary sealing element—ngesiqhelo i-elastomer O-ring—nge-metallic core eqhubekayo neguquguqukayo. Olu tshintsho lubalulekileyo kuyilo lususa ubuthathaka obunxulunyaniswa nokuwohloka kwe-elastomer, nto leyo enika ithuba elikhethekileyo loomatshini kwiimeko ezithile zokuphathwa kolwelo.

Kutheni ukukhetha kuchaphazela ukuthembeka kunye neendleko zomjikelo wobomi

Ulwalamano phakathiukukhetha isitywino soomatshinikwaye ukuthembeka kwezityalo ixesha elide akunakugqithiswa. Kwiimeko zenkqubo enzima, ukusilela kwetywina loomatshini kubangela phantse i-70% yexesha elipheleleyo lokungasebenzi kwepompo. Ukuphuculwa kuyilo lwentsimbi kwiizicelo ezinemidiya enamandla kunokutshintsha kakhulu i-Mean Time Between Failures (MTBF).

Umzekelo, iimpompo ze-centrifugal ezisebenza kwiindawo zokucoca ezishushu kakhulu zihlala zibona i-pusher seal MTBF ime kwiinyanga ezili-12 ukuya kwezili-18 ngenxa yokuqina kwe-elastomer. Ngokutshintshela kwi-mechanical seal ye-mechanical bellows echazwe ngokufanelekileyo, izakhiwo zihlala zandisa i-MTBF ukuya kwiinyanga ezingaphezu kwama-36 ukuya kuma-60. Nangona inkcitho yokuqala ye-metal bellows unit iphezulu, iindleko zomjikelo wobomi (LCC) ziyehla ngokukhawuleza xa kujongwa ukususwa kokucima okungacwangciswanga, ukunciphisa umsebenzi wokulungisa, kunye nokungabikho kwemfuneko yokutshintshwa kwe-shaft sleeve.

Indlela iimeko zokusebenza ezichaphazela ngayo ukhetho lwesitywina

Iiparameter zokusebenza—ingakumbi ubushushu, uburhabaxa beekhemikhali, kunye nokuxinana kolwelo—zezona zinto ziphambili ekukhetheni isitywina. Ii-fluoroelastomers eziqhelekileyo (FKM) okanye ii-perfluoroelastomers (FFKM) zihlala zibonisa ukuwohloka kobushushu okanye ukuphuma xa amaqondo obushushu aqhubekayo edlula i-200°C ukuya kwi-260°C (392°F ukuya kwi-500°F).

Ngokwahlukileyo koko, iintsimbi zesinyithi ezidityaniswe ngomphetho ezakhiwe ngee-alloys ezisebenza kakuhle zinokumelana kakuhle nobushushu obuqhubekayo bokusebenza obudlula i-400°C (750°F) ngaphandle kokulahlekelwa bubume besakhiwo okanye uxinzelelo lwentwasahlobo. Ngaphezu koko, iimeko zokusebenza kwelinye icala zilawula ukhetho olufanayo; usetyenziso lwe-cryogenic olusebenza ukuya kuthi ga kwi--75°C (-103°F) lubangela ukuba ii-elastomers ziqhekeke kwaye ziqhekeke, nto leyo eyenza iintsimbi zesinyithi zibe lolona khetho lobunjineli olusebenzayo lokulayisha ubuso obuzinzileyo.

Iintsimbi zeMetal Bellows vs Pusher Mechanical Seals

Ukuze benze iinkcukacha ezichanekileyo, iinjineli kufuneka ziqonde umahluko phakathi kwee-pusher seals kunye nee-non-pusher metal bellows seals. I-pusher seal isebenzisa i-dynamic secondary elastomer ekufuneka ihambe, okanye "ityhale," ecaleni kwe-pump shaft okanye kwi-sleeve ukuze ihlawulele ukuguguleka kobuso be-seal kunye nokwandiswa kobushushu. I-metal bellows seal ngokwemvelo ayisiyo-pusher.

Kwisimo esingashukumisiyo, iyunithi ye-bellows ngokwayo ivalwa ngokuhambelana ne-shaft okanye kwi-sleeve, ngesiqhelo nge-static O-ring okanye i-graphite wedge. Yonke intshukumo ye-axial efunekayo ukugcina unxibelelwano lobuso ifunxwa kukugoba kwe-metallic convolutions, okuphelisa ngokupheleleyo imfuneko yokuba i-elastomer ityibilike ngokuguquguqukayo.

Indlela uyilo ngalunye oludala ngayo ukuguquguquka kunye nokulayisha ubuso

Uyilo lwe-Pusher luxhomekeke kwizipringi ze-coil enye okanye ezininzi ukubonelela ngamandla okuvala oomatshini afunekayo kubuso besitywino. Njengoko i-O-ring eguquguqukayo ityibilika ukugcina lo mthwalo, ii-particles zinokuqokelelana kwi-shaft, nto leyo ebangela ukuba i-elastomer ixhome. Oku kuxhomeka kukhokelela ekuqhekekeni kobuso kunye nokuvuza kwangoko. Ngaphezu koko, iintshukumo ezincinci eziqhubekayo ze-O-ring eguquguqukayo nxamnye nomphezulu wesinyithi zihlala zibangela ukuxinana okukhulu kwe-shaft.

Itywina lesinyithi elisebenzisa i-mechanical bellows lisombulula ezi ngxaki ngokuhambisa umthwalo wobuso ofanayo, ongama-360-degree ngqo kwi-metallic convolutions. Ngenxa yokuba akukho ntshukumo ye-elastomer yesibini, i-shaft fretting iyasuswa ngokupheleleyo. Ukusasazwa okufanayo koxinzelelo lwentwasahlobo kukwanciphisa ukugqwetheka kobuso bendawo, kugcina umsantsa othe tyaba wokutywina phantsi koxinzelelo olutshintshatshintshayo.

Yeyiphi imida yokusebenza ebaluleke kakhulu

Ukuqonda imida yokusebenza echanekileyo yoyilo zombini kubalulekile ekuthinteleni ukungaphumeleli kwepompo enkulu. Ukuqina kunye noxinzelelo lweenxalenye zento zizinto ezixinzelelweyo kakhulu. Iisprings ze-pusher seal zisengozini enkulu yokuvaleka xa ulwelo lugqithisile kwi-1,500 cSt okanye xa izinto eziqinileyo ezixhonyiweyo ziqokelelana kwiipokotho zesprings.

Ngenxa yokuba iintsimbi zentsimbi azinazo iingxowa zentwasahlobo eziqinileyo, zibamba ubunzulu obufikelela kwi-3,000 cSt ngaphambi kokuba zifune ukulungiswa okukhethekileyo. Xa zicwangciswe njengeentsimbi ezijikelezayo, amandla e-centrifugal alahla iinxalenye eziphuma kwiingqungquthela, nto leyo enika isiphumo sokuzicoca esingenakukwazi ukuphinda siphindaphindwe.

Iikhrayitheriya eziphambili zokuthelekisa isitywina

Ukuthelekisa iintlobo zesitywina kufuna uphononongo olucwangcisiweyo lwemilinganiselo yokusebenza, iimpembelelo zoqoqosho, kunye nemigangatho yokuthobela indalo. Amaqela obunjineli kufuneka alinganise amandla oomatshini akhawulezileyo ngokuthelekisa nomgangatho wokusebenza kwexesha elide wezixhobo.

Nangona iintsimbi zentsimbi zigqwesile kwiimeko ezinzima, ukukhethwa kwazo kufuneka kuqinisekiswe ngokuthelekisa iikhrayitheriya ezingqongqo, ukuqinisekisa ukuba iteknoloji iyahambelana neemfuno zenkqubo kunyeamaqhinga okugcina izityalo.

Indlela yokuthelekisa izinto zokusebenza

Uthelekiso lwentsebenzo luxhomekeke kakhulu kwimida yoxinzelelo kunye nesantya seshaft. Ii-pusher seals, ingakumbi ezo zinezakhiwo ezilinganayo, zinobuchule kakhulu ekusingatheni uxinzelelo olugqithisileyo, zihlala zilinganiswa kwiindawo ezingaphaya kwe-100 bar (1,450 psi). Iintsimbi zesinyithi, nangona ziguquguquka kakhulu, zijongene nemida yesakhiwo malunga noxinzelelo.

Iintsimbi zesinyithi ezenziwe ngokwesiqhelo zihlala zilinganiselwe kwiingcinezelo ezimalunga neebha ezingama-20 (290 psi). Iintsimbi zesinyithi ezidityaniswe ngomphetho ophezulu zinokwandisa lo mda ukuya kuthi ga kwiibha ezingama-69 (1,000 psi), kodwa zihlala zinobuzwe obuphezulu kwiingcinezelo kunee-pusher seals ezinzima. Xa kuthelekiswa isantya se-shaft, iintsimbi zesinyithi ezikumgangatho ophezulu zinokusebenza ngokukhululekileyo kwisantya somphezulu ukuya kuthi ga kwi-25 m/s, nto leyo eyenza ukuba zikhuphisane kakhulu kwiimilinganiselo zepompo ye-API eqhelekileyo.

Zeziphi izinto ekufuneka ziqwalaselwe ngeendleko kunye nomjikelo wobomi

Uhlalutyo lweendleko kufuneka lutshintshe ukusuka kwimbono yeCapEx kuphela ukuya kwimodeli epheleleyo yeendleko zobunini (TCO). Iindleko zokuqala zokuthenga zesitywina somatshini sentsimbi esidityaniswe ngomphetho zihlala ziphezulu nge-2.0x ukuya kwi-3.0x kunesitywina somatshini esiqhelekileyo se-elastomer ngenxa yobunzima besinyithi kunye nokuwelda okuchanekileyo okufunekayo.

Nangona kunjalo, izinto ezibangela umjikelo wobomi zikhawuleza ziwutshintshe lo mgangatho wokuqala. Ngokususa isidingo sokutshintsha ii-fretted pump shafts okanye ii-protective sleeves—ezinokubiza ngaphezulu kwe-$2,000 ngokulungiswa ngakunye kwiimpompo ezinkulu ze-API—kwaye ngokwandisa i-MTBF ngeminyaka eliqela, imbuyekezo kutyalo-mali (ROI) yokuphucula i-metal bellows idla ngokufumaneka kwiinyanga ezili-12 ukuya kwezili-18 zokuqala zokusebenza.

Apho iimfuno zokuthobela imithetho zichaphazela ukhetho

Imithetho yokusingqongileyo idlala indima enkulu ekukhetheni izitywini, ingakumbiamacandelo eekhemikhali kunye neekhemikhaliIzakhiwo mazilandele imigangatho engqongqo yokukhupha ukungcola, njenge-EPA Method 21, edla ngokuyalela ukuba ukuvuza kwezixhobo kuhlale ngaphantsi kwe-500 parts per million (ppm) ye-volatious organic compounds (VOCs).

Iiseal zeMetal Bellows zithandwa kakhulu kwiindlela zokuthobela imithetho kuba zisusa i-O-ring enamandla, eyindawo eqhelekileyo yokusilela kokukhutshwa kwezinto ezingafunekiyo. Kwizicelo zokucoca ezilawulwa yimigangatho ye-API 682, iiseal zeType B (metal Bellows) zichazwe ngokucacileyo kwiinkonzo zobushushu obuphezulu zeDigri 2 kunye neDigri 3, ukuqinisekisa ukuthotyelwa kwemiyalelo yokusingqongileyo kunye nemigangatho yokhuseleko yamazwe ngamazwe.

Isikhokelo Sokukhetha Nokufumaneka Kwezinto Ezifunekayo

Ukutshintsha ukusuka ekukhetheni ngokwethiyori ukuya ekufumaneni okusebenzayo kufuna indlela ecwangcisiweyo. Ukuthenga isitywina somatshini esifakwe isinyithi asikokuthengiselana ngezinto ezithengiswayo; kufuna unxibelelwano oluchanekileyo lobunjineli phakathi kweqela elithembekileyo lezityalo kunye neqela elilawulayo.umenzi wesitywino.

Inkqubo yovavanyo oluqinileyo kunye neyokufaneleka iqinisekisa ukuba isitywina esihanjisiweyo siya kusebenza kwi-MTBF yaso echaziweyo, sithintele ukusetyenziswa gwenxa okubizayo.

Yeyiphi inkqubo yokuvavanya ekufuneka isetyenziswe

Inkqubo yokuvavanya kufuneka iqale ngohlalutyo olupheleleyo lolwelo kunye nenkqubo. Iinjineli kufuneka zibhale phantsi ulwakhiwo oluchanekileyo lweekhemikhali, kuquka nezinto ezilandelelanayo, ukuqinisekisa ukuhambelana kwesinyithi. Ukupompa ulwelo olunemilinganiselo elinganayo yeekloridi kunokubangela ukuqhekeka koxinzelelo kwimibhobho yentsimbi engatyiwayo ye-300-series.

Okulandelayo, kufuneka kuchazwe i-envelope yokufaka isicelo. Oku kuquka ukucwangcisa amaqondo obushushu aphantsi naphezulu okusebenza, uxinzelelo oluqhubekayo nolwexeshana, kunye nepesenti yezinto eziqinileyo ezixhonyiweyo. Kuphela emva kokuba le mvulophu imiselwe apho ukucoca kuya kukhetha uhlobo lolwakhiwo lwe-bellows—ukukhetha phakathi kwe-bellows ezenziweyo zezicelo eziphantsi okanye i-bellows ezidityanisiweyo ukuze kusebenze kakhulu.

Zeziphi iinkcukacha zeenkcukacha ezihlala ziphosakele

Iinkcukacha ezininzi ezibalulekileyo zeenkcukacha azinakwa rhoqo ngexesha lokuthengwa, nto leyo ekhokelela ekuphelelweni kukudinwa kwangethuba. Enye yezo nkcukacha bubukhulu bepleyiti ye-bellows. Iipleyiti ezisemgangathweni ezidityaniswe ngomphetho ziqala kwi-0.10 mm ukuya kwi-0.15 mm ubukhulu. Ukuchaza ipleyiti etyebileyo (umz., 0.20 mm) kwandisa umlinganiselo woxinzelelo kodwa kunciphisa kakhulu ukuguquguquka kwe-axial, nto leyo edinga ukubalwa kwakhona kwamandla okulayisha ubuso.

Ukukhetha i-alloy yenye into engaqhelekanga ephoswa rhoqo. Ukutshintsha i-AM350 kusenokusindisa iindleko kwangaphambili, kodwa ukuphucula i-Alloy C-276 okanye i-Inconel 718 kuyimfuneko xa kujongwana nezinto ezirhabaxa okanye amaqondo obushushu angaphezulu kwama-315°C. Ukungacacisi i-metallurgy echanekileyo kwi-fluid chemistry ethile yimbangela ephambili yokuqhekeka kwe-bellows kwangoko.

Indlela yokuqinisekisa ababoneleli kunye nabathengisi

Ukufaneleka komthengisi ngeentsimbi zesinyithi kufuna ukuvavanya amandla abo okuvelisa kunye nokuqinisekisa umgangatho. Abathengi kufuneka bagunyazise isiqinisekiso se-ISO 9001 kwaye bacele amaxwebhu ovavanyo lwesinyithi lwangaphakathi. Ngenxa yokuba inkqubo yokuwelda emphethweni ibandakanya amawaka ee-micro-welds, umthengisi kufuneka enze uvavanyo oluqatha lokuvuza.

Abathengisi abamkelekileyo kufuneka basebenzise uvavanyo lokuvuza kwe-helium mass spectrometry, ukuqinisekisa izinga lokuvuza elingaphantsi kwe-1×10^-7 atm cc/sec kulo lonke i-bellows assembly. Ngaphezu koko, abathengi kufuneka balindele iindlela ezahlukeneyo zokuhambisa izinto; ngelixa ii-pusher seals zihlala zizinto zorhwebo ezingaphandle kweshelufu (COTS), ii-bellows ezenziwe ngemiphetho ezidityanisiweyo zihlala zifuna ubungakanani obuphantsi be-oda (MOQ) okanye amaxesha okuthwala eeveki ezi-6 ukuya kwezi-8. Izatifikethi zezinto ezilandelekayo (ezifana ne-EN 10204 3.1) kufuneka zibe yimfuneko engenakuphikiswana ukuqinisekisa ubunyani be-alloy.

Xa iiMetal Bellows Seals zilungelelene kakhulu

Ukuchonga indlela echanekileyo yokufaneleka kwesitywini somatshini sentsimbi esisebenza ngentsimbi kufuna ukufanisa amandla akhethekileyo obu buchwephesha neendlela ezithile zokusilela ezifumaneka kwisityalo. Xa zisetyenziswa ngokuchanekileyo, ezi zitywini zisebenza njengesisombululo esiqinisekileyo kwimiba engapheliyo yokuthembeka kwepompo.

Nangona zingathatyathelwa indawo yiyo yonke imitywino yokutyhala, ukusetyenziswa kwazo kwiindawo ezijolise kuzo nezixinezelekileyo kuvelisa uzinzo olungenakuthelekiswa nanto lokusebenza.

Zeziphi izicelo ezixhasa i-metal bellows

Okuthileizicelo zoshishinoNgokwemvelo ithanda uyilo lwe-metal bellows. Ukucutshungulwa kwe-hydrocarbon enobushushu obuphezulu, njengokupompa i-asphalt eshushu okanye i-oyile yegesi ye-vacuum enzima (HVGO), kufuna izitywino ezingayi kujika okanye zibophe. Iimpompo zokudlulisa ubushushu (i-oyile eshushu) ezisebenza kakuhle ngaphezu kwama-200°C zixhomekeke kuphela kwi-metal bellows ukuthintela ukusilela okukhulu okunxulunyaniswa nokunyibilika kwe-elastomer.

Ukongeza, ukusetyenziswa okubandakanya izinto eziqinileyo ezirhabaxa ezifikelela kwi-5% ngobunzima zezona zinto zibalulekileyo. Kwezi meko, ii-O-rings eziguquguqukayo zee-pusher seals zitshatyalaliswa ngokukhawuleza yi-particle scoring, kwaye ii-coil springs zazo zizaliswe zizinto eziqinileyo. I-seal yentsimbi ejikelezayo ekhupha ezi zinto ziqinileyo nge-centrifugally, igcina ukulayisha kobuso okufanelekileyo kwaye ithintela i-seal ukuba ingaxhonywa.

Yeyiphi isikhokelo esinceda amaqela akhethe ngokuzithemba

Ukuze ukhethe ngokuzithemba, amaqela obunjineli kufuneka asebenzise i-standard decision matrix. Ukuba usetyenziso ludlula i-200°C, lusebenza ngaphantsi kwe--40°C, lubandakanya izinyibilikisi ezinamandla ezidumba ii-elastomers, okanye lunengxaki yokuxinana kwe-shaft okungapheliyo, isitywina se-mechanical bellows sensimbi kufuneka sibe yinkcazo emiselweyo.

Amaqela kufuneka abeke phambili imilinganiselo yokuthembeka kwexesha elide kunebhajethi yokuthenga. Ukumisela ulungelelwaniso kwi-API 682 Uhlobo B lweeasethi ezifanelekileyo kwenza kube lula ukufakwa kwezinto kwaye kuqinisekisa ukuba xa kuvela iimeko ezinzima, iteknoloji yokutywina sele yenzelwe ukumelana noxinzelelo lobushushu nolwemishini, ekugqibeleni ikhusele imveliso yezityalo kunye nabasebenzi.

Izinto ezibalulekileyo ekufuneka ziqwalaselwe

• Izigqibo ezibaluleke kakhulu kunye nesizathu sokutywinwa kwesinyithi phantsi koomatshini
• 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 i-mechanical seal ye-mechanical bellows endaweni ye-elastomer bellow seal?

Khetha i-metal bellows xa kukho ubushushu obuphezulu, iikhemikhali ezirhabaxa, umsebenzi we-cryogenic, okanye xa i-shaft fretting kunye ne-O-ring hang-up ziyingozi. I-Elastomer bellows ingena kwiinkonzo ezicocekileyo nezinobushushu obuphakathi.

Luluphi udidi lobushushu olwenza ukuba izitywini zentsimbi zibe lolona khetho lungcono?

Iintsimbi zentsimbi zihlala zithandwa ngaphezu kwama-200°C kwaye zinokuthwala ama-400°C+ kuxhomekeke kwi-alloy. Zikwafanelekile kumaqondo obushushu aphantsi kakhulu apho ii-elastomers zinokuqhekeka khona.

Kutheni izitywino zentsimbi ziphucula ukuthembeka kwepompo?

Basebenzisa uyilo olungasebenzisi sixhobo sokucinezela, ngoko ke akukho slayidi ye-elastomer enamandla kwi-shaft. Oku kunceda ukuthintela ukuxhoma, kunciphisa umngcipheko wokuvuza, kwaye kuphelisa ukuxinana kwe-shaft kwinkonzo enzima.

Ngaba iVictor Seals ingabonelela ngeentsimbi zentsimbi ezitywiniweyo zokutshintshwa kweepompo ze-OEM?

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

Ngaba ii-metal bellow seals zingcono kwiincindi eziqinileyo okanye ezimdaka?

Kudla ngokuba njalo. Uyilo lwentsimbi olusebenzisa i-metal bellows luthintela ukuvaleka kwe-spring-pocket okuxhaphakileyo kwezinye izitywina ze-pusher kwaye lunokumelana nokuqina okuphezulu, nto leyo ebenza basebenziseke kwimisebenzi enzima yokupompa kwemizi-mveliso.