Uhlalutyo lweengxaki zobuchwepheshe ezijongene nofakelo lwevalvu kunye nokutshintshwa kokupakisha kwisikhululo samandla

Uhlalutyo lweengxaki zobuchwepheshe ezijongene nofakelo lwevalve kunye nokutshintshwa kokupakisha kwisikhululo samandla Indawo yofakelo lwevalvu kufuneka ibe lula ukusebenza; Nangona ukufakela kunzima okwethutyana, kuyimfuneko ukuqwalasela umsebenzi wexesha elide lomsebenzisi. Kungcono ukuthabatha ivili lesandla sevalve kunye nesifuba (ubukhulu becala yi-1.2 yeemitha ukusuka kumgangatho wokusebenza), ukuze kube lula ukuvula nokuvala ivalve. I-handwheel yevalve yomhlaba kufuneka iphakame, musa ukuthambeka, ukunqanda ukusebenza kakubi. Ivalve yomatshini wodonga ixhomekeke kwisixhobo, kodwa kwakhona ukushiya indawo yokuba umqhubi ame. Ukuphepha ukusebenza kwesibhakabhaka, ngakumbi iasidi kunye nealkali, imidiya enetyhefu, kungenjalo ayikhuselekanga kakhulu. Ivalve yesango akufanele iguqulwe (okt ivili lesandla phantsi), kungenjalo i-medium iya kugcinwa kwindawo yokuvala ivalve ixesha elide... yandise ukusebenza kakuhle kwayo. Umgangatho wofakelo lwe-valve luchaphazela ngokuthe ngqo ukusetyenziswa, ngoko kufuneka kuqwalaselwe ngenyameko. (1) Umkhombandlela kunye nesikhundla Iivalve ezininzi zinendlela yokuqondisa, njengevalve yeglowubhu, ivalve ye-throttle, ivalve yokunciphisa uxinzelelo, ivalve yokukhangela, njl., ukuba ifakwe ngasemva, iya kuchaphazela ukusebenza kunye nobomi (njengevalve ye-throttle), okanye ayisebenzi kwaphela (njengevalve yokunciphisa uxinzelelo), okanye ibangele ingozi (njengevalve yokukhangela). Iivalvu ngokubanzi, iimpawu zendlela kumzimba wevalvu; Kwimeko apho akukho, kufuneka ichongwe ngokuchanekileyo ngokwemigaqo yokusebenza yevalve. Igumbi levalve yevalve yeglowubhu ayilinganisi, ngoko ke ulwelo kufuneka lugqithwe kwizibuko levalve ukusuka ezantsi ukuya phezulu, ukuze ukuxhathisa ulwelo kuncinci (kumiselwa yimilo), ukonga umsebenzi ovulekileyo (ngenxa yoxinzelelo oluphakathi phezulu. ), emva kokuvala i-medium ayicinezeli ukupakisha, ukugcinwa lula. Kungenxa yoko le nto ivalve yeglowubhu ayinakufakwa. Ezinye iivalve zineempawu zazo. Indawo yokufakela i-valve kufuneka ilungele ukusebenza; Nangona ukufakela kunzima okwethutyana, kuyimfuneko ukuqwalasela umsebenzi wexesha elide lomsebenzisi. Kungcono ukuthabatha ivili lesandla sevalve kunye nesifuba (ubukhulu becala yi-1.2 yeemitha ukusuka kumgangatho wokusebenza), ukuze kube lula ukuvula nokuvala ivalve. I-handwheel yevalve yomhlaba kufuneka iphakame, musa ukuthambeka, ukunqanda ukusebenza kakubi. Ivalve yomatshini wodonga ixhomekeke kwisixhobo, kodwa kwakhona ukushiya indawo yokuba umqhubi ame. Ukuphepha ukusebenza kwesibhakabhaka, ngakumbi iasidi kunye nealkali, imidiya enetyhefu, kungenjalo ayikhuselekanga kakhulu. Ivalve yesango ayiguquki (oko kukuthi, ivili lesandla phantsi), kungenjalo iya kwenza ukuba indawo ephakathi igcinwe kwindawo yesigqubuthelo sevalve ixesha elide, i-corrosion elula yesiqu, kwaye kwezinye iimfuno zenkqubo taboo. Kunzima kakhulu ukutshintsha ukupakisha ngaxeshanye. Vula iivalvu zesango lesikhondo, musa ukufaka ngaphantsi komhlaba, kungenjalo ukufuma kuya konakalisa isikhondo esivelileyo. Phakamisa i-valve yokukhangela, ukufakela ukuqinisekisa ukuba i-disc nkqo, ukuze uphakamise ukuguquguquka. Iivalvu zokujonga ujingi kufuneka zifakwe kunye ne-pin shaft ethe tyaba ukuze ujingi oguquguqukayo. Ivalve yokukhulula uxinzelelo kufuneka ifakwe kwindawo ethe tye kumbhobho othe tye, kwaye akufuneki ithotywe kulo naliphi na icala. (2) Imisebenzi yokwakha Ufakelo kunye nokwakhiwa kufuneka kulumke, ungabetheli izinto ezinqabileyo ezenziwe ngevalve. Ngaphambi kokufakela, i-valve kufuneka ihlolwe ukujonga iinkcukacha kwaye ichonge ukuba kukho nawuphi na umonakalo, ngakumbi kwisiqu. Kwakhona ujike amaxesha ambalwa ukuze ubone ukuba igobile, kuba kwinkqubo yokuthutha, ** kulula ukubetha i-valve stem. Kwakhona *** inkunkuma yevalvu. Xa i-valve iphakanyisiwe, intambo akufanele iboshwe kwi-handwheel okanye kwisiqu ukuphepha umonakalo kwezi ndawo, kodwa kufuneka iboshwe kwi-flange. Ngombhobho oqhagamshelwe kwivalve, qiniseka ukuba ucocekile. Umoya ocinezelweyo unokusetyenziselwa ukuvuthela i-iron oxide, isanti, i-welding slag kunye nobunye ubumdaka. Ezi sundries, akukho lula kuphela ukukrwela umphezulu wokutywina wevalve, kubandakanywa amasuntswana amakhulu e-sundries (njenge-welding slag), kodwa kunye nokufaka i-valve encinci, ukuze ingaphumeleli. Faka ivalve yesikrufu, kufuneka ibe ukupakishwa kokutywina (umsonto kunye neoyile yelothe okanye ibhanti lezinto ezikrwada zeptfe), ipakethe kumsonto wombhobho, ungafiki kwivalve, ukuze ungabikho kwimveliso yememori yevalve, echaphazela ukuhamba kweendaba. Xa ufaka i-valve ene-flanged, qinisa iibholithi ngokulinganayo kwaye ngokulinganayo. I-valve flanges kunye ne-pipe flanges kufuneka ihambelane, kwaye ukukhutshwa kunengqiqo ukuphepha uxinzelelo olugqithiseleyo okanye ukuqhekeka kwevalve. Kwizinto ezinqabileyo kunye namandla aphantsi e-valve, ngokukodwa ingqalelo. Ivalve ekufuneka idityaniswe ngombhobho kufuneka idityaniswe ngebala kuqala, emva koko ivule ngokupheleleyo iindawo zokuvala, ize idityaniswe ngokufa. (3) Izixhobo zokukhusela Ezinye iivalve nazo zifuna ukhuseleko lwangaphandle, oluyi-insulation kunye nokupholisa. Umbhobho wokulandela ubushushu ngamanye amaxesha uyongezwa kumaleko wokugquma. Luhlobo luni lwevalve ekufuneka ifakwe i-insulated okanye ibanda, ngokweemfuno zemveliso. Ngokomgaqo, apho i-valve medium ukunciphisa ubushushu kakhulu, kuya kuchaphazela ukusebenza kwemveliso okanye ivalve emkhenkceni, kufuneka ugcine ubushushu, okanye ubushushu; Apho ivalve iveze khona, ivelisa kakubi okanye ibangele iqabaka kunye nezinye izinto ezimbi, kufuneka ukhusele ingqele. Izinto zokugquma i-asbestos, uboya be-slag, uboya beglasi, i-perlite, i-diatomite, i-vermiculite kunye nokunye; Gcina izinto ezibandayo zine-cork, i-perlite, i-foam, iplastiki yokulinda. Iivalvu zamanzi kunye ne-steam ezingasetyenziswanga ixesha elide kufuneka zikhutshwe. (4) Iindlela zokudlula kunye nezixhobo Ezinye iivalvu zineendlela zokudlula kunye neegeyiji ukongeza kukhuseleko oluyimfuneko. Kufakwe i-bypass ukuququzelela ukugcinwa komgibe. Ezinye iivalve nazo zifakwe nge-bypass. Ukufakwa kwe-Bypass kuxhomekeke kwimeko yevalve, ukubaluleka kunye neemfuno zokuvelisa. (5) Ukutshintshwa kwe-filler Stock valves, ukupakisha okunye akulungile, kwaye ezinye azihambelani nokusetyenziswa kweendaba, ezifuna ukubuyisela ukupakisha. Abavelisi be-valve abanakukwazi ukuqwalasela ukusetyenziswa kwamawaka eeyunithi zeendaba ezahlukeneyo, ibhokisi yokupakisha isoloko igcwele ukupakisha okuqhelekileyo, kodwa xa usebenzisa, kufuneka uvumele umhluzi kunye nophakathi ukulungelelanisa. Xa utshintshela isigcwalisi, cinezela ujikeleze kwaye ujikeleze. Ikhonkco ngalinye leringi lifanelekile ukuya kuma-degrees angama-45, umsesane kunye nekhonkco elidibeneyo ligxadazela li-180 degrees. Ukuphakama kokupakisha kufuneka kuthathelwe ingqalelo igumbi loxinzelelo olongezelelweyo lwegland. Okwangoku, indawo engezantsi ye-gland kufuneka icinezelwe ukuya kubunzulu obufanelekileyo begumbi lokupakisha, elinokuthi ngokubanzi libe yi-10-20% yobuninzi begumbi lokupakisha. Kwiivalvu ezifunayo, i-Angle yomthungo yi-30 degrees. Amalungu phakathi kwamakhonkco agxininiswe ngamadigri angama-120. Ukongeza kokupakishwa ngasentla, kodwa kwakhona ngokwemeko ethile, irabha O ring (ukumelana irabha yendalo ukuya 60 degrees Celsius buthathaka alkali, butanol ukuxhathisa irabha ukuya 80 degrees Celsius iimveliso yeoli, Fluorine irabha ukumelana neentlobo zeendaba ezonakalisayo ngezantsi. I-150 degrees celcius) isangqa esimithathu se-polytetrafluoroethylene (ixhathisa kumajelo eendaba ezonakalisayo angaphantsi kwama-200 ngokukaCelsius) isangqa sesitya senayiloni (esingevani ne-ammonia, ialkali engaphantsi kwe-120 ngokukaCelsius) kunye nezinye ukwenza isihluzi. I-polytetrafluoroethylene (PTFE) i-tape eluhlaza isongelwe ngaphandle kwekhoyili ye-asbestos eqhelekileyo, enokuphucula umphumo wokutywina kunye nokunciphisa i-electrochemical corrosion of the stem. Xa ucofa ukupakisha, jika isiqu ngaxeshanye ukusigcina sijikeleze kwaye uthintele ukufa okuninzi. Qinisa idlala ngokulinganayo kwaye ungathambeki. Kukho izalathisi ezininzi zokulinganisa umgangatho wevalvu: ukuthembeka kokutywina, ukukwazi ukuphendula isenzo, amandla, ukuqina kunye nobomi, njl njl. iimfuno. Ukuqinisekisa ezi zalathi, ezi ngxaki zilandelayo zifuna ukusonjululwa kuqala. 1 Ulawulo (misela ukuthembeka kwesenzo sevalvu) Ukusilela kwenkqubo yokulawula yevalve ephambili yomphunga kunye nevalve yokufudumeza umphunga yenye yeengozi ezintlanu ezinkulu ze turbine yomphunga, ebonakaliswa ikakhulu ekuvulekeni kwevalve ayihambelani noyilo, kubandakanywa ukungaphumeleli kwendlela yokuhambisa, ukuqhubela phambili kwe-stroke kunye ne-lag, echaphazela amandla kunye nokungcangcazela kwevalve. Ulawulo lokuvula i-valve luchaphazela ngokuthe ngqo imeko yokusebenza ye-injini ye-steam, ngoko ixabiswa kakhulu kwaye ibe yenye yeengxaki ezibalulekileyo kuphando. Kwiminyaka yakutshanje, kuphononongo lokuthembeka kwevalve, ivalve ekrelekrele yeyona ndlela yophando, ivalve ekrelekrele inomsebenzi wokuzigweba iimeko zokusebenza, kunye nexesha lokwenyani lokuzilawula. Inxalenye ephambili yevalve ekrelekrele sisimo sedijithali. I-digital positioner isebenzisa i-microprocessor ukubeka i-actuator yevalve ngokuchanekileyo, ukubeka iliso kunye nokurekhoda idatha efanelekileyo yevalve. I-2 Amandla (kufuneka ihlangabezane neemfuno zobomi kunye nokuqina) Ukuqala rhoqo kweyunithi kumandla evalve kunye nobomi benkonzo yevalve buvelele ngakumbi, ngakumbi ngevalve yokulawula ye-injini yomphunga, ingqwalasela yophando lwangaphambili. kwingxaki yokulawula i-valve, ngoku kubonakala ngathi amandla engxaki ayinakuhoywa. UCarolann Giovando, usekela umhleli wephephancwadi i-Power Engineering, ubhala ukuba abaphandi akufanele bagxininise ngokukodwa kwiingxaki zokulawula, kodwa kumandla, ubomi kunye nokutywinwa, okuyimfuneko ekusebenzeni kwevalve. (1) Ngenxa yokuqaliswa rhoqo kweyunithi, isivalo somphunga sokuqala sisenokungafikeleli iimfuno ezintsha zokusebenza. Ngenxa yokuba ivalve ephambili yomphunga iyilwe ngokomthwalo osisiseko, inkqubo yoyilo kuphela ngokoxinzelelo oluzinzileyo, ubushushu, uvavanyo lokunyuka kwamandla ayo, akukho ngxaki yobomi bokudinwa komjikelo ophantsi. Ngoku iimeko zokusebenza ziyatshintsha, uyilo lwangaphambili alukwazi ukuhlangabezana neemfuno. Ngoko ke, kuyimfuneko ukuqwalasela umjikelo ophantsi wokukhathala koyilo lobomi kwinkqubo yoyilo, ukwenzela ukuba imeko yoyilo ihambelane nemeko yokusebenza, ukuze kufezekiswe injongo yokwandisa ubomi. (2) Ngenxa yokuchaneka kokulawulwa kwe-stroke ye-actuator, i-spool inomthwalo wempembelelo kwisihlalo. Kubekho ukuqhekeka kwezihlalo zezityalo zamandla, ibhloko yokuqhekeka iye yagxalathelana kwi-injini yomoya, okubangele ukwehla okubukhali kwimveliso yeinjini yomoya, umonakalo omkhulu werotor wempazamo. Ukongeza, kwiivalvu zoxinzelelo oluphezulu, kunye ne-cavitation phenomenon, iziphene zokuqala zokuphosa umzimba wevalve, umzimba wevalve emva kokuhlalutya ubomi bokuqhekeka kunye nokuxela kwangaphambili kuyafaneleka ukufundwa ngakumbi. I-3 vibration Utshintsho lokuvula i-valve, ukungasebenzi kakuhle kwe-activator kunye nokuvuza kwevalve ngunobangela wokungcangcazela, umonakalo we-vibration kwivalve ngokwayo incinci kakhulu, kodwa impembelelo kwiyunithi yonke inkulu, kwi-oscillation ephantsi-frequency. I-oscillation ye-low-frequency oscillation yeyunithi ihlukaniswe kwiindidi ezimbini: enye i-oscillation yefilimu yeoli, eveliswa yifilimu yeoli exhasa ukuthwala kwiyunithi yesantya okanye akukho mthwalo wokusebenza; Enye i-steam oscillation, enzima ngakumbi kune-oscillation yefilimu yeoli. Ingcangcazela phantsi kwesenzo samandla okuvuselela umphunga kwaye kaninzi kwenzeka emva kokuba iyunithi ilayishiwe. Utshintsho lokuvula i-valve kunye nokuvuza zizizathu ezibalulekileyo zokujikeleza komphunga. Idatha ibonisa ukuba i-United States kunye neJamani zineengozi zokuphahlazeka kwe-steam oscillation, e-China kuye kwenzeka kwakhona iingozi ze-50 MW kunye ne-200 MW kunye neengozi ze-turbine ye-turbine ye-200, ngenxa yokunqongophala kweerekhodi zedatha yexesha lokwenene, ngoko ke unobangela wokungaphumeleli awunakuqinisekiswa, kodwa ukrokrela ukuba inxulumene nee-oscillations ezimbini ezisezantsi-frequency. Ngaloo ndlela, ukupheliswa kunye nokunciphisa i-oscillations ye-steam kubaluleke kakhulu, okuxhomekeke kwisifundo esicwangcisiweyo sokutshintshwa kwe-valve yokuvula kunye nemikhosi yokuvuselela eyenziwa ngokuvuza. Amathuba okuba i-oscillation yomphunga ingancitshiswa ngokuyila ngokufanelekileyo ivalve yokuvula kunye ne-stroke yokuvala. 4 Ukuvuza (ukuvuza kwangaphakathi kunye nokuvuza kwangaphandle) (1) Ukuvuza akukona nje unobangela wokungcangcazela, kodwa kubangela ungcoliseko nokulahleka kwamandla. Ukusombulula ingxaki yokuvuza, ukuya kuthi ga kwinqanaba elithile, inkqubo inokuphepha ukungcangcazela, kodwa iphinde yandise ubomi bezixhobo, iphucule ukusebenza kakuhle. (2) Ubomi bevalve yoxinzelelo oluphezulu lweyunithi ye-supercritical ngamanye amaxesha bufutshane kakhulu, kwaye ukupakishwa kufuneka kutshintshwe emva kwamaxesha amaninzi okuqala. Kuyimfuneko ukufunda ukupakisha okutywina okutsha okanye ukuyila ifomu entsha yokutywina esebenzayo ukwandisa ubomi kunye nokuphucula ukuthembeka kokusebenza kolu hlobo lwesivalo soxinzelelo oluphezulu. - Okwangoku, inqanaba lesethi epheleleyo yeevalve iyaqhubeka nokuphucula, kuphela ukusombulula iingxaki ezingentla kakuhle, ukwenzela ukuba kuqinisekiswe ukusebenza okubanzi kwe-valve kunye nomgangatho ongcono.