Yisiphi Isivalo Semishini Esishisa Kakhulu Esihlala Isikhathi Eside Ngempela?

Isingeniso

Ekusetshenzisweni kwezinga lokushisa eliphezulu, isikhathi sokuphila kwesivalo somshini sincike kokungaphezu kwesilinganiso sezinto zaso noma umkhawulo wokushisa ophezulu. Ukuqina kwangempela kuvela endleleni umklamo wesivalo ophatha ngayo ukuphambuka kokushisa, ukugcotshwa kobuso, izinguquko zokucindezela, kanye nezimo zokusekela ngokuhamba kwesikhathi. Lesi sihloko siqhathanisa izinhlobo zesivalo ezivame ukusetshenziswa ngaphezu kuka-200°C, sichaza ukuthi kungani ezinye zehluleka kusenesikhathi naphezu kokubukeka zifanelekile ephepheni, futhi sibonisa ukuthi yiziphi izici zomklamo ezithonya kakhulu impilo yokusebenza. Ekugcineni, abafundi bazoba nesisekelo esicacile sokwahlulela ukuthi yisiphi isivalo somshini somshini sokushisa okuphezulu esihlala isikhathi eside ekusetshenzisweni kwepompo nezinqubo ezidingayo.

Kungani Impilo Yesevisi Yesivalo Ibalulekile Ezicelweni Zokushisa Okuphezulu

Izimpawu zokusebenza zemishiniEzindaweni ezidlula u-200°C (392°F) kwethula izinselele ezinkulu ze-thermodynamic kanye ne-metallurgical. Kulezi zicelo zokushisa okuphezulu, ukunquma ukuthi yiluphi ukwakheka kwe-seal olunikeza impilo ende yesevisi kudinga ukuhlaziya kokubili ukuqina kokushisa kwe-seal kanye nokuguquguquka kwesistimu ezungezile. I-seal ehlala isikhathi eside akuyona nje into eqinile; iyisici esiyinhloko sokusebenza okuqhubekayo nokuphephile kwesitshalo.

Umthelela wokuvalwa, ukuvuza, kanye nokugcinwa

Imiphumela yezezimali kanye nokusebenza kokwehluleka kokuvalwa ngaphambi kwesikhathi ezinhlelweni zokushisa okuphezulu inkulu kakhulu. Ukuqhuma okukodwa kwe-seal okuyingozi kakhuluiphampu yoketshezi olushisayokungaholela ekuvalweni kwezitshalo ngokushesha, kanti izindleko zesikhathi sokungasebenzi ezindaweni zokucwenga uphethiloli zivame ukwedlula u-$50,000 ngehora. Ngaphezu kwalokho, ukuvuza kokushisa okuphezulu kudala izingozi ezinkulu zokuphepha kanye nezemvelo, okuhlanganisa nokushisa ngokuzenzakalelayo kwama-volatile organic compounds (ama-VOC) kanye nokwephulwa kwemithetho eqinile yokukhishwa komoya okusabalele, okuvame ukuphoqelela amazinga okuvuza angaphansi kwezingxenye ezingu-500 ngesigidi (ppm). Isikhathi eside senkonzo sinciphisa ngqo lezi zingozi zezimali nezemvelo ezingamukeleki.

Izicelo lapho impilo yesivalo iqhuba khona ukukhetha

Isidingo sokuqina kwesikhathi eside kwesivalo sibonakala kakhulu ezimbonini eziqhubeka nokusebenza. Amaphampu amanzi okuphakelwa ngamabhoyila, asebenza emazingeni okushisa afinyelela ku-250°C (482°F) kanye nokucindezela okungaphezu kwama-bar angu-150, adinga izivalo ezingamelana nokushintsha kwesigaba okusheshayo kanye nokukhanya koketshezi. Ngokufanayo, amaphampu okudlulisa ukushisa (i-HTF) ajikeleza uwoyela wokwenziwa ku-350°C kuya ku-400°C (662°F kuya ku-752°F) adingaizindlela ezikhethekile zokuvalaezimelana nokuwohloka okukhulu kokushisa. Ezindaweni zokucwilisa ze-vacuum kanye namayunithi okupheka aphuzile, lapho ama-hydrocarbon asindayo ebhaka khona abe yizinto eziqinile ezirhabaxa, ikhono le-mechanical seal lokusinda ekushiseni okukhulu ngaphandle kokuvaleka liba yimbangela eyinhloko yokukhethwa kwemishini.

Yini Enquma Ukuphila Kwesivalo Semishini Ekushiseni Okuphezulu

Ukuphila isikhathi eside kwesivalo somshini ngaphansi kokushisa okukhulu kunqunywa ikhono laso lokugcina ifilimu yoketshezi ezinzile, ukumelana nokuphambuka okukhulu kokushisa, kanye nokwamukela ukwanda kokushisa okuhlukile kwezingxenye zaso zangaphakathi. Lapho amazinga okushisa enyuka, i-viscosity yoketshezi iyehla, isunduza ubuso besivalo eduze kokugcotshwa komngcele kanye nokusheshisa ukuguguleka.

Izici zokuklama uphawu

Umklamo wokwakha wesivalo yiwona oyinhloko obangela ukukhuthazela okuphezulu kokushisa. Izivalo zokucindezela, ezithembele kuma-O-rings ashukumisayo ukuze zithuthukise ubuso besivalo njengoba siguga, zisengozini enkulu "yokulenga" lapho ama-elastomer ewohloka noma lapho kucubungula ama-coke oketshezi emgodleni. Ngokuphambene nalokho, izivalo zensimbi ezihlanganisiwe ezihlanganisiwe zibhekwa njengezinga elijwayelekile embonini lamazinga okushisa angaphezu kuka-260°C (500°F). Ngokususa i-dynamic secondary elastomer, izivalo zokucindezela zigcina ukulayishwa kobuso okuhambisanayo futhi zivumela ukunwetshwa komgodi ngaphandle kwengozi ye-O-ring carbonization.

Izinto zokwakha ubuso, izimpawu zesibili, kanye nezingxenye zensimbi

Ukukhetha izinto kubalulekileukuze kuqiniswe ukushisa. Kuma-seal faces, i-sintered silicon carbide (SiC) inikeza ukuhanjiswa kokushisa okuhle kakhulu futhi ingamelana namazinga okushisa emvelo afinyelela ku-1,400°C, yize isengozini yokushaqeka kokushisa. I-tungsten carbide ehlanganiswe ne-carbon graphite ekhethekile engamelani nama-blister ivame ukuthandwa ekusetshenzisweni kwe-petroleum okushisa okuphezulu. Kuma-seal esibili, ama-perfluoroelastomers (FFKM) afinyelela umkhawulo wawo wokushisa ophelele eduze kuka-327°C (620°F). Ngale kwalo mkhawulo, ama-wedge e-graphite aguquguqukayo noma ukupakisha kwe-Grafoil—okukwazi ukumelana namazinga okushisa afinyelela ku-450°C (842°F) ezindaweni ezifaka i-oxidizing kanye namazinga okushisa angaphezu kuka-1,000°C ezindaweni ezingasebenzi kahle—kumele kusetshenziswe. I-Metallurgy yama-bellows ngokuvamile idinga ama-alloy ane-nickel ephezulu njenge-Alloy 718 noma i-Hastelloy C-276 ukuvimbela ukukhukhuleka kokushisa okuphezulu nokugcina amazinga entwasahlobo aqondile.

Izindlela zokwehluleka ezivamile ngaphansi kokushisa

Ukushisa kubangela izindlela ezithile zokwehluleka ezifinyeza kakhulu impilo yesivalo. Ukuphambuka kokushisa, njengokugoba noma ukugoba, kushintsha igebe elincane phakathi kobuso besivalo, okuholela ekuvuza okukhulu noma ekusebenzeni okomile. Ukugoba kwenzeka lapho ama-hydrocarbon ewohloka ebusweni besivalo esishisayo, kwakha ama-carbon deposits abrasive abhubhisa ukuthamba kobuso. Ngaphezu kwalokho, ukukhishwa kwe-elastomer kanye nokuhlola ukushisa (ukuqhekeka okuncane kobuso obuqinile ngenxa yokujikeleza okusheshayo kokushisa) kubangela ukwehluleka okungaphezu kuka-40% kwangaphambi kwesikhathi ezinqubweni ezisebenza ngokuqhubekayo ngaphezu kuka-200°C.

Indlela Yokuqhathanisa Izimbozo Zemishini Ezishisa Kakhulu

Ukuqhathanisa izivalo zokushisa okuphezulu kudinga indlela yokuhlaziya, ukuhlola imikhawulo yokusebenza eguquguqukayo kanye nomthelela wezomnotho wesikhathi eside kunokuthembela kuphela ezilinganisweni zokushisa ezimile eziphrintiwe ephepheni lemininingwane.

Izindlela zokusebenza ezibalulekile

Onjiniyela kumele bahlole umkhawulo wesivinini sokucindezela (i-PV), ochaza ikhono lesivalo lokusingatha ukushisa okukhuhlayo okukhiqizwa ebusweni bokuhlangana. Izivalo zokushisa eziphezulu ezisebenza kahle kumele zisekele kahle amanani e-PV adlula ama-50,000 psi-ft/min (17.5 MPa-m/s) ngaphandle kokukhanyisa ifilimu yoketshezi. Ngaphezu kwalokho, ukubekezelela ukuthamba kobuso kumele kugcinwe ngokuqinile ngaphansi komthwalo wokushisa, ngokuvamile kudinga ukuqinisekiswa kokukhanya kwamabhande okukhanya e-helium angu-2 kuya kwangu-3 (cishe ama-micron angu-0.58 kuya ku-0.87) ukuqinisekisa ukusatshalaliswa komthwalo okufanayo nokuvimbela ukuhlolwa kokushisa kwendawo.

Ithebula lokuqhathanisa lokuhlolwa kwesivalo

Ithebula elilandelayo liqhathanisa ukwakheka okubili okuyinhloko kwesivalo okusetshenziswa ekusetshenzisweni kwezinga lokushisa eliphezulu, okugqamisa ukuthi kungani imiklamo ethile ihlala isikhathi eside kuneminye ekushiseni okukhulu.

Izindleko zomjikelezo wokuphila kanye ne-MTBF

Nakuba uphawu lwensimbi oluhlanganisiwe olunezingqimba lungase lube nezindleko zokuthenga zokuqala eziphakeme ngo-150% kuya ku-200% uma kuqhathaniswa nophawu olujwayelekile lokucindezela, ezomnotho zomjikelezo wokuphila zikhetha kakhulu umklamo othize ohambisana nokushisa okuphezulu. I-Mean Time Between Failures (MTBF) iyisilinganiso esibalulekile sokuphila isikhathi eside kwangempela. Ukuthuthukisa i-ipompo kawoyela oshisayoUkuze kube nophawu olukhethekile lwe-bellows, i-MTBF inganweba i-MTBF isuke ezinyangeni ezingu-8 ezingamukeleki iye ezinyangeni ezingaphezu kuka-48. Uma kuhlanganiswa umsebenzi, izingxenye ezithathelwanayo, futhi kugwenywe isikhathi sokungasebenzi, izindleko eziphelele zobunikazi (TCO) esikhathini seminyaka emihlanu zivame ukuncishiswa ngo-40% noma ngaphezulu.

Indlela Yokuhlola Nokukhetha Uphawu Olufanele

Ukuqinisekisa uphawu lomshini ngenxa yokushisa okukhulu kudinga izindlela zokuhlola eziqinile kanye nendlela engaguquki yokuqinisekisa ikhwalithi kanye nemibhalo ngaphambi kokuba uphawu lufike phansi esitshalweni.

Izinyathelo zokukhetha ukugwema ukwehluleka kusenesikhathi

Ukukhetha uphawu olufanele kuhilela ukunamathela ngokuqinile ezindinganisweni zemboni, ikakhulukazi i-API 682 yemikhakha kawoyela, igesi, kanye ne-petrochemical. Isinyathelo esibalulekile ekugwemeni ukwehluleka kwangaphambi kwesikhathi ukukhetha uhlelo olufanele lwamapayipi. Ngokuvamile, uphawu alukwazi ukusinda emazingeni okushisa aphezulu kakhulu enqubo ngqo. Ukusebenzisa uhlelo lwe-API 23, oluphinda lujikeleze uketshezi ngesibandisi sesivalo, noma uhlelo lwe-API Plan 53B barrier fluid, kunganciphisa izinga lokushisa legumbi lesivalo kusukela ku-350°C kuye ku-150°C olawulekayo. Ukuhlola izidingo zokushabalaliswa kokushisa kohlelo lokushabalalisa kubaluleke njengokukhetha uphawu olungokoqobo.

Ikhwalithi yokukhiqiza kanye nokulandeleka kwezinto ezibonakalayo

Ukubekezelelana kokukhiqiza kwezivalo zokushisa okuphezulu akushiyi ndawo yamaphutha. Ubuqotho bokushisela ezimbotsheni zensimbi bubaluleke kakhulu; abakhiqizi kumele basebenzise ukushisela okuqondile kwe-micro-plasma futhi benze ukuhlolwa kokuvuza kwe-helium mass spectrometry kuze kufike emkhawulweni ongu-1 × 10^-8 atm cc/sec ukuqinisekisa ukuthi izimbotshana ngeke ziqhume ngaphansi kokujikeleza okukhulu kokushisa. Ngaphezu kwalokho, ukulandeleka kwezinto kuyimpoqo, njengoba ukwakheka kwamakhemikhali okuqondile kwe-bellows alloy kunquma ngqo impilo yayo yokukhathala ekushiseni okuphezulu kanye nokugcinwa kwentwasahlobo.

Izidingo zokuthobela imithetho kanye nemibhalo

Imibhalo yokuthobela imithetho inikeza ubufakazi bekhwalithi edingekayo engqalasizinda ebalulekile. Onjiniyela kufanele badinge imibiko yokuhlolwa kwezinto zohlobo lwe-EN 10204 Type 3.1 (MTRs) yazo zonke izingxenye zensimbi ezigcina ingcindezi nezishintshashintshayo. Ezisetshenzisweni lapho amazinga okushisa aphezulu ehlanganiswa negesi emuncu noma izinto ezigqwalisayo, ukuthobela ngokuqinile i-NACE MR0175/ISO 15156 kuyadingeka ukuvimbela ukuqhekeka kokucindezeleka kwe-sulfide ezingxenyeni zensimbi yesivalo emazingeni okushisa aphezulu.

Indlela Yokukhetha Izimo Ezihlukene Zokusebenza

Ekugcineni, uphawu lomshini oluhlala isikhathi eside yilolo oluhambisana ncamashi nezakhiwo ezithile ze-thermodynamic zoketshezi lwenqubo kanye nezinga lokusebenza kwemishini yokupompa.

Isiqondiso sokukhetha ngokwebanga loketshezi kanye nokushisa

Izici zoketshezi zilawula isu lokuvala ukushisa. Amanzi ashisa kakhulu (ukudla kwebhoyila) anamafutha amancane kakhulu futhi avutha ngokushesha lapho kwehla ingcindezi, okudinga izinhlelo ezikhethekile zokupholisa ezinomfutho ophezulu. Ngakolunye uhlangothi, amafutha ashisayo anikeza amafutha angcono kodwa athambekele kakhulu ekubhodleni nasekuqineni lapho evezwa emoyeni.

Uhlaka lwesinqumo sokukhetha kokugcina

Uhlaka lwesinqumo sokugcina kumele luhlanganise izinga lokushisa, ingcindezi, kanye nokuhambisana kwamakhemikhali. Onjiniyela kumele babale ama-coefficients okukhulisa ukushisa ahlukene phakathi kwesikhwama sepompo, i-shaft, kanye ne-seal gland. Uma lezi zingxenye zanda ngamazinga ahlukene kakhulu ngesikhathi sokuqalisa, kungakheka igebe elikhulu lokukhipha elingaphezu kuka-0.15 mm, okuholela ekuqhumeni kwe-seal ngokushesha kungakhathaliseki ukuthi izinga lokushisa langaphakathi le-seal lingakanani. Ngokubeka izilinganiso ezilinganisweni zensimbi ezimile nge-graphite secondary seals zokushisa ezingaphezu kuka-260°C, nokuzisekela ngezinhlelo zokupholisa ze-API eziqinile, opharetha bangafinyelela impilo yenkonzo yeminyaka eminingi ngokuthembekile ezinhlelweni zokushisa ezidinga kakhulu.

Izinto Ezibalulekile Okufanele Uzicabangele

• Iziphetho ezibaluleke kakhulu kanye nesizathu sokuthi Yisiphi Isivalo Semishini Esihlala Isikhathi Eside Ngempela?
• Imininingwane, ukuhambisana, kanye nokuhlolwa kwengozi okufanele kuqinisekiswe ngaphambi kokuthi uzibophezele
• Izinyathelo ezilandelayo ezisebenzayo kanye nezixwayiso abafundi abangazisebenzisa ngokushesha

imibuzo ejwayelekile ukubuzwa

Yisiphi isivalo somshini esishisa kakhulu esivame ukuhlala isikhathi eside ngaphezu kuka-260°C?

Isivalo sensimbi esihlanganisiwe esinomugqa oqondile sivame ukuhlala isikhathi eside ngoba sigwema ukulenga kwe-dynamic elastomer futhi siphatha kangcono ukukhula nokushisa komgodi.

Kungani izimbobo zokucindezela zihluleka ngokushesha enkonzweni yepompo eshisayo?

Ama-O-ring abo anamandla angaqina, afake i-carbon, noma anamathele emgodleni, okubangela ukulandelela ubuso okungekuhle, ukuvuza, kanye nokuguguleka okusheshayo emsebenzini oqhubekayo wokushisa okuphezulu.

Yiziphi izinto zobuso ezilungele ukuhlala isikhathi eside ukuvala uma izinga lokushisa liphezulu?

Izinketho ezivamile zokuphila isikhathi eside yi-silicon carbide yokudlulisa ukushisa kanye ne-tungsten carbide ene-carbon engamelani nama-blister yezinsizakalo ze-petroleum eshisayo kanye ne-hydrocarbon.

Ingabe iVictor Seals ingakunikeza izinto zokushintsha ezihambisana ne-OEM ezisezingeni eliphezulu?

Yebo. I-Victor Seals inikeza izivalo zemishini 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.

Amaqembu okulungisa angayandisa kanjani impilo yesivalo kumaphampu ashisa kakhulu?

Qinisekisa ukusebenza kohlelo lokuhlanza, gwema ukusebenza okomile, lawula ukushaqeka kokushisa, hlanganisa izinto noketshezi kanye nokushisa, bese ushintsha izivalo ngaphambi kokuba ukupheka kulimaze ubuso.