Apho Zisetyenziswa khona iivalvu: Kuyo yonke indawo!

08 Nov 2017 Ibhalwe ngu Greg Johnson

Iivalvu zifumaneka malunga naphi na namhlanje: kumakhaya ethu, phantsi kwesitrato, kwizakhiwo zorhwebo kunye nakumawaka eendawo ezingaphakathi kwamandla kunye nezityalo zamanzi, ii-mills zamaphepha, iindawo zokucoca, izityalo zemichiza kunye nezinye izibonelelo zoshishino kunye neziseko.
Ushishino lwevalvu lunamagxa abanzi ngokwenene, anamacandelo awohluka ukusuka kunikezelo lwamanzi ukuya kumandla enyukliya ukuya phezulu nasezantsi kwe-oyile negesi. Nganye kwezi mveliso zabasebenzisi bokugqibela zisebenzisa ezinye iintlobo ezisisiseko zeevalvu; nangona kunjalo, iinkcukacha zokwakha kunye nezixhobo zihlala zihluke kakhulu. Nantsi iisampulu:

AMANZI ASEBENZA
Kwihlabathi losasazo lwamanzi, uxinzelelo luhlala luphantsi kwaye namaqondo obushushu ahambelana. Ezo nyaniso zimbini zokusetyenziswa zivumela inani lezinto zoyilo lwevalvu ezingafunyaniswanga kwisixhobo esicela umngeni ngakumbi njengezivalo zobushushu obuphezulu. Ubushushu benkonzo yamanzi buvumela ukusetyenziswa kwee-elastomers kunye ne-rubber seal engafanelekanga kwenye indawo. Ezi zixhobo zithambileyo zivumela iivalvu zamanzi ukuba zixhotyiswe ukuze zivale ngokuqinileyo iidriphu.

Olunye uqwalaselo kwiivalvu zenkonzo yamanzi lukhetho kwizinto zokwakha. Iintsimbi ze-Cast kunye ne-ductile zisetyenziswa kakhulu kwiinkqubo zamanzi, ngakumbi imigca emikhulu yangaphandle. Imigca emincinci kakhulu inokubanjwa kakuhle ngemathiriyeli yevalvu yobhedu.

Uxinzelelo olubonwa ziivalvu ezininzi zemisebenzi yamanzi lukholisa ukuba ngaphantsi kwe-200 psi. Oku kuthetha ukuba uyilo olushinyeneyo olunoxinzelelo oluphezulu alufuneki. Oko sele kuthethiwe, kukho iimeko apho iivalvu zamanzi zakhiwe ukujongana noxinzelelo oluphezulu, ukuya kuthi ga kwi-300 psi. Ezi zicelo zihlala kwimisele emide ekufutshane nomthombo woxinzelelo. Ngamanye amaxesha izivalo zamanzi ezinoxinzelelo oluphezulu nazo zifumaneka kwezona ndawo zoxinzelelo ziphezulu kwidama elide.

I-American Water Works Association (AWWA) ikhuphe iinkcukacha ezigubungela iindidi ezininzi zeevalvu kunye ne-actuator ezisetyenziswa kwizicelo zamanzi.

AMANZI AMANZI
Icala elisecaleni lamanzi okusela amatsha angena kwindawo okanye kwisakhiwo ngamanzi amdaka okanye umjelo ophumayo. Le migca iqokelela yonke inkunkuma kunye nezinto eziqinileyo kwaye iziqondise kwindawo yokucoca ilindle. Ezi zityalo zonyango zinemibhobho emininzi yoxinzelelo oluphantsi kunye neevalvu ukwenza "umsebenzi wabo omdaka." Iimfuno zeevalvu zamanzi amdaka kwiimeko ezininzi zilula kakhulu kuneemfuno zenkonzo yamanzi acocekileyo. Isango lentsimbi kunye neevalve zetshekhi zezona zikhetho ezidumileyo zolu hlobo lwenkonzo. Iivalve ezisemgangathweni kule nkonzo zakhiwe ngokuhambelana neenkcukacha ze-AWWA.

ISHISHINI LAMANDLA
Uninzi lwamandla ombane aveliswa eMelika aveliswa kwizityalo zomphunga kusetyenziswa iifosili kunye nee turbines ezinesantya esiphezulu. Ukukrazula umva isigqubuthelo somzi-mveliso wanamhlanje kuya kunika umbono woxinzelelo oluphezulu, iinkqubo zemibhobho yobushushu obuphezulu. Ezi ntambo zingundoqo zezona zibalulekileyo kwinkqubo yokuvelisa amandla ngomphunga.

Iivalve zesango zihlala zilukhetho oluphambili lweplanti yamandla kwi/off applications, nangona injongo ekhethekileyo, iivalve zeglobhu zeY-pattern nazo zifunyenwe. Ukusebenza okuphezulu, iivalvu zebhola zenkonzo ebalulekileyo zifumana ukuthandwa ngabayili beplanti yamandla kwaye ziyangena kweli lizwe lalikade lilawulwa yivalve.

I-Metallurgy ibaluleke kakhulu kwiivalvu kusetyenziso lwamandla, ngakumbi ezo zisebenza kuluhlu oluphezulu okanye lwe-ultra-supercritical yokusebenza koxinzelelo kunye nobushushu. I-F91, i-F92, i-C12A, kunye ne-Inconel ezininzi kunye ne-stainless-steel alloys zisetyenziswa ngokuqhelekileyo kwizityalo zamandla zanamhlanje. Iiklasi zoxinzelelo zibandakanya i-1500, i-2500 kwaye kwezinye iimeko 4500. Ubume bomodareyitha bezityalo zamandla eziphakamileyo (ezo zisebenza kuphela njengoko zifuneka) nazo zibeka uxinzelelo olukhulu kwiivalvu kunye nemibhobho, efuna uyilo elomeleleyo lokusingatha indibaniselwano egqithisileyo yebhayisikile, ubushushu kunye uxinzelelo.
Ukongeza kwi-valve ye-steam engundoqo, izityalo zamandla zilayishwa ngemibhobho encedisayo, ehlala ngamasango amaninzi, i-globe, i-check, i-butterfly kunye ne-valve yebhola.

Amaziko asebenza ngenyukliya asebenza kumgaqo ofanayo womphunga/isantya esiphezulu somoya. Umahluko ophambili ngowokuba kwisikhululo samandla enyukliya, umphunga udalwa bubushushu obuvela kwinkqubo yokuqhekeka. Iivalvu zesityalo samandla enyukliya ziyafana nabazala babo abaphenjelelwe yifosili, ngaphandle komnombo wabo kunye nemfuneko eyongeziweyo yokuthembeka ngokupheleleyo. Iivalvu zenyukliya zenziwe zaya kumgangatho ophezulu kakhulu, kunye namaxwebhu afanelekileyo kunye nokuhlolwa azalise amakhulu amaphepha.

UKUVELISWA KWE-OLI NEGASI
Imithombo yeoli kunye negesi kunye nezixhobo zokuvelisa ngabasebenzisi abanzima beevalvu, kubandakanywa iivalve ezininzi ezinzima. Nangona imijelo yeoli igalela amakhulu eemitha emoyeni ingenakufane yenzeke, lo mfanekiso ubonisa uxinezeleko olunokubakho lweoli negesi engaphantsi komhlaba. Yiloo nto iintloko zequla okanye imithi yeKrisimesi ibekwe phezulu kumtya omde wombhobho. Ezi ndibano, kunye nokudibanisa kwazo iivalve kunye nezixhobo ezikhethekileyo, zenzelwe ukujongana noxinzelelo olungaphezulu kwe-10,000 psi. Ngelixa kunqabile ukuba kufumaneke kumaqula ambiweyo emhlabeni kwezi ntsuku, uxinzelelo oluphezulu kakhulu luhlala lufumaneka kumaqula anzulu onxweme.

Uyilo lwezixhobo ze-Wellhead lugutyungelwe yimigaqo ye-API efana ne-6A, iNkcazo ye-Wellhead kunye neZixhobo zoMthi weKrisimesi. Iivalvu ezigqunywe kwi-6A zenzelwe uxinzelelo oluphezulu kakhulu kodwa ubushushu obuphantsi. Uninzi lwemithi yeKrisimesi ineevalvu zesango kunye neevalvu ezikhethekileyo zeglowubhu ezibizwa ngokuba zii-chokes. Izikrweqe zisetyenziselwa ukulawula ukuphuma kwequla.

Ukongeza kwii-wellheads ngokwazo, izibonelelo ezininzi ezincedisayo zihlala kwindawo yeoli okanye igesi. Izixhobo zokusebenza zokunyanga ioli okanye igesi kwangaphambili zifuna inani leevalvu. Ezi valves zidla ngokuba yi-carbon steel rated kwiiklasi ezisezantsi.

Ngamathub’ athile, ulwelo oluyingozi kakhulu—ihydrogen sulfide—lubakho kumjelo wepetroleum ekrwada. Esi sixhobo, esikwabizwa ngokuba yigesi emuncu, sinokubulala. Ukubetha imingeni yegesi emuncu, izinto ezikhethekileyo okanye iindlela zokulungisa izinto ngokuhambelana nenkcazo ye-NACE International MR0175 kufuneka ilandelwe.

OKWENZIWA NGASEKUNXULENI
Iinkqubo zemibhobho ye-oyile ye-offshore kunye nezixhobo zokuvelisa ziqulethe intaphane yeevalvu ezakhiwe kwiinkcukacha ezininzi ezahlukeneyo ukujongana nemingeni ebanzi yokulawula ukuhamba. Ezi zixhobo zikwaqulethe i-loops yenkqubo yokulawula eyahlukeneyo kunye nezixhobo zokunciphisa uxinzelelo.

Kwizibonelelo zokuvelisa i-oyile, intliziyo ye-arterial yeyona nkqubo ye-oyile okanye i-gas recovery piping system. Nangona ingasoloko ikwiqonga ngokwalo, iinkqubo ezininzi zokuvelisa zisebenzisa imithi yeKrisimesi kunye neenkqubo zemibhobho esebenza kubunzulu obungenabugorha obuziimitha ezili-10,000 nangaphezulu. Esi sixhobo sokuvelisa sakhiwe kwimigangatho emininzi echanekileyo ye-American Petroleum Institute (API) kwaye ibhekiselele kwii-API ezininzi ezicetyiswayo (RPs).

Kwiiplatifti ezininzi zeoyile, iinkqubo ezongezelelweyo ziyasetyenziswa kulwelo olukrwada oluvela kwintloko yomthombo. Oku kuquka ukwahlula amanzi kwiihydrocarbons kunye nokwahlula igesi kunye nolwelo lwerhasi yendalo kumsinga wolwelo. Ezi nkqubo zemibhobho yasemva komthi weKrisimesi ziqhele ukwakhelwa kwi-American Society of Mechanical Engineers B31.3 iikhowudi zemibhobho enevalvu eziyilwe ngokungqinelana ne-API valve speciments ezifana ne-API 594, API 600, API 602, API 608 kunye ne-API 609.

Ezinye zezi nkqubo zinokuqulatha isango le-API 6D, ibhola kunye neevalvu zokukhangela. Ekubeni nayiphi na imibhobho ekwiqonga okanye inqanawa yokugrumba ingaphakathi kwiziko, iimfuno ezingqongqo zokusebenzisa iivalvu ze-API 6D kwimibhobho ayisebenzi. Nangona iintlobo zevalve ezininzi zisetyenziswa kwezi nkqubo zemibhobho, uhlobo lwevalve ekhethiweyo yivalve yebhola.

IMIbhobho
Nangona uninzi lwemibhobho lufihliwe ekubonweni, ubukho bayo budla ngokubonakala. Iimpawu ezincinci ezichaza “umbhobho wepetroleum” sesinye isalathisi esicacileyo sobukho bemibhobho yothutho engaphantsi komhlaba. Le mibhobho ixhotyiswe ngeevalvu ezininzi ezibalulekileyo kubo bonke ubude bayo. Iivalvu zokuvala imibhobho yongxamiseko zifumaneka ngamaxesha athile njengoko kuchazwe ngokwemigangatho, iikhowudi kunye nemithetho. Ezi zivalo zisebenza inkonzo ebalulekileyo yokwahlula icandelo lombhobho xa kukho ukuvuza okanye xa kufuneka ukulungiswa.

Kwakhona zihlakazekile ecaleni kwendlela yombhobho zizibonelelo apho umgca uvela emhlabeni kunye nokufikelela komgca kufumaneka. Ezi zikhululo likhaya lezixhobo zokuphehlelela “zehagu”, eziquka izixhobo ezifakwe kwimibhobho yokuhlola okanye yokucoca umgca. Ezi zikhululo zokuqalisa iihagu zikholisa ukuqulatha iivalvu ezininzi, nokuba yisango okanye iindidi zebhola. Zonke iivalvu ezikwisixokelelwano semibhobho kufuneka zibe yi-full-port (ivuleke ngokupheleleyo) ukuvumela ukudlula kweehagu.

Imibhobho nayo ifuna amandla ukulwa nokukhuhlana kombhobho kunye nokugcina uxinzelelo kunye nokuhamba komgca. I-Compressor okanye izitishi zokumpompa ezibukeka njengeenguqu ezincinci zesityalo senkqubo ngaphandle kweenqaba ezide eziqhekezayo zisetyenziswa. Ezi zikhululo zilikhaya kuninzi lwamasango, iivalvu zebhola kunye neetshekhi zemibhobho.
Iipayipi ngokwazo ziyilwe ngokuhambelana nemigangatho eyahlukeneyo kunye neekhowudi, ngelixa iivalve zepayipi zilandela i-API 6D Pipeline Valves.
Kukwakho nemibhobho emincinci ezondla ezindlwini nakwizakhiwo zorhwebo. Le migca ibonelela ngamanzi kunye negesi kwaye igadwe ngeevalvu zokuvala.
Oomasipala abakhulu, ngakumbi kumantla e-United States, babonelela ngomphunga kwiimfuno zokufudumeza kubathengi borhwebo. Le migca yokubonelela nge-steam ixhotyiswe ngeendidi ezahlukeneyo zokulawula kunye nokulawula ukunikezelwa komphunga. Nangona ulwelo lungumphunga, uxinzelelo kunye namaqondo obushushu angaphantsi kunalawo afumaneka kumatshini wokuvelisa umphunga. Iindidi ezahlukeneyo zevalve zisetyenziswa kule nkonzo, nangona ivalve yeplagi ebekekileyo iselukhetho oludumileyo.

UKUCOQWA KUNYE NEPETROCHEMICAL
Iivalvu zokucoca zibangela usetyenziso oluninzi lwevalvu yeshishini kunalo naliphi na elinye icandelo levalvu. Iindawo zokucokisa zilikhaya kuzo zombini ulwelo oludlekayo kwaye kwezinye iimeko, amaqondo obushushu aphezulu.
Ezi zinto zilawula indlela iivalve ezakhiwe ngayo ngokuhambelana neenkcukacha zoyilo lwevalve ye-API ezifana ne-API 600 (iivalvu zesango), i-API 608 (iivalve zebhola) kunye ne-API 594 (i-valve yokujonga). Ngenxa yenkonzo erhabaxa efunyanwa luninzi lwezi zivalo, isibonelelo esongezelelweyo somhlwa siyafuneka. Esi sibonelelo sibonakaliswa ngobunzima obukhulu beendonga obuchazwe kumaxwebhu oyilo lwe-API.

Phantse lonke uhlobo lwevalvu engundoqo inokufumaneka ngobuninzi kwindawo yokucokisa enkulu eqhelekileyo. Ivalve yesango ekuyo yonke indawo iseyinkosi yenduli enabona bantu baninzi, kodwa iivalvu zekota zokujika zithatha isixa esikhulu esikhulayo sesabelo sazo semarike. Iimveliso zekota eziye zangena ngempumelelo kolu shishino (olwalukhe lwalawulwa ziimveliso zomgca) luquka ukusebenza okuphezulu kweevalvu zebhabhathane eziphindwe kathathu kunye neevalvu zebhola ezihlala ngentsimbi.

Isango eliqhelekileyo, iglowubhu kunye neevalvu zokutshekisha zisafumaneka en-masse, kwaye ngenxa yentliziyo yoyilo kunye noqoqosho lwemveliso, aziyi kunyamalala naliphi na ixesha kungekudala.
Ukulinganiswa koxinzelelo kwiivalvu zokucoca ziqhuba i-gamut ukusuka kwiKlasi ye-150 ukuya kwiKlasi ye-1500, kunye neKlasi ye-300 ethandwa kakhulu.
Iintsimbi zekhabhoni ezingenanto, ezifana ne-WCB yebakala (i-cast) kunye ne-A-105 (i-forged) zezona zinto zidumileyo ezichazwe kwaye zisetyenziswe kwiivalvu zenkonzo yokucoca. Iinkqubo ezininzi zokusulungekisa izicelo zityhala iqondo lobushushu eliphezulu leentsimbi zekhabhoni engenanto, kunye nengxubevange yobushushu obuphezulu bucaciswe kwezi zicelo. Eyona nto idumileyo kwezi ziyi-chrome / moly steels ezifana ne-1-1 / 4% Cr, 2-1 / 4% Cr, 5% Cr kunye ne-9% Cr. Iinsimbi ezingenasici kunye ne-high-nickel alloys nazo zisetyenziswa kwezinye iinkqubo zokucokisa eziqatha.

IKHEMIkhali
Ishishini lemichiza ngumsebenzisi omkhulu weevalvu zazo zonke iintlobo kunye nemathiriyeli. Ukusuka kwizityalo zebhetshi ezincinci ukuya kwizakhiwo ezinkulu zepetrochemical ezifumaneka kwiGulf Coast, iivalvu ziyinxalenye enkulu yenkqubo yemibhobho yekhemikhali.

Uninzi lwezicelo kwiinkqubo zeekhemikhali ziphantsi koxinzelelo kuneenkqubo ezininzi zokucokisa kunye nokuveliswa kwamandla. Ezona klasi zidumileyo zoxinzelelo lweevalvu zezityalo zekhemikhali kunye nemibhobho yodidi lwe-150 kunye ne-300. Izityalo zemichiza zikwangoyena mqhubi wesabelo semalike ethathwayo apho iivalvu zebhola ziye zajijisana ukusuka kwivalvu emide kule minyaka ingama-40 idlulileyo. Ivalve yebhola eyomelelayo, ene-zero-leakage shutoff, ifanelekile kwizicelo ezininzi zezityalo zekhemikhali. Ubungakanani obubambeneyo bevalve yebhola luphawu oludumileyo ngokunjalo.
Kusekho ezinye izityalo zemichiza kunye neenkqubo zezityalo apho iivalvu ezinqamlekileyo zikhethwa khona. Kule meko, iivalve ezidumileyo ze-API 603, ezineendonga ezincinci kunye nezisindo ezilula, ngokuqhelekileyo isango okanye i-valve yeglobhu ekhethiweyo. Ulawulo lweminye imichiza lukwafezekiswa ngokufanelekileyo nge-diaphragm okanye i-pinch valves.
Ngenxa yendalo eyonakalisayo yeekhemikhali ezininzi kunye neenkqubo zokwenza imichiza, ukukhethwa kwezinto eziphathekayo kubaluleke kakhulu. Izinto ze-defacto ziyi-316 / 316L ibakala le-austenitic stainless steel. Esi sixhobo sisebenza kakuhle ukulwa umhlwa ukusuka kumanzi amaninzi ngamanye amaxesha abi.

Kwezinye izicelo ezomeleleyo ezonakalisayo, ukhuseleko oluthe kratya luyafuneka. Amanye amabakala aphezulu okusebenza kwe-austenitic stainless steel, i-317, i-347 kunye ne-321 idla ngokukhethwa kwezi meko. Ezinye i-alloys ezisetyenziswa ngamaxesha ngamaxesha ukulawula ulwelo lweekhemikhali ziquka i-Monel, i-Alloy 20, i-Inconel kunye ne-17-4 PH.

I-LNG KUNYE NEGASI
Zombini irhasi yendalo engamanzi (LNG) kunye neenkqubo ezifunekayo zokwahlulwa kwerhasi zixhomekeke kwimibhobho ebanzi. Ezi zicelo zifuna iivalvu ezinokusebenza kumaqondo obushushu asezantsi kakhulu e-cryogenic. Ishishini le-LNG, elikhula ngokukhawuleza e-United States, lihlala lijonge ukuphucula nokuphucula inkqubo yokukhutshwa kwegesi. Ukuza kuthi ga ngoku, imibhobho kunye neevalvu ziye zaba nkulu kakhulu kwaye iimfuno zoxinzelelo ziye zanyuswa.

Le meko ifune ukuba abavelisi bevalvu baphuhlise uyilo ukuhlangabezana nemilinganiselo eqinile. Ibhola yekota kunye neevalvu zebhabhathane zithandwa kakhulu kwinkonzo ye-LNG, kunye ne-316ss [intsimbi engenasici] eyona nto idumileyo. Udidi lwe-ANSI 600 luxinzelelo oluqhelekileyo lwesilingi kwizicelo ezininzi ze-LNG. Nangona iimveliso zekota zezona zithandwa kakhulu kwiintlobo zevalvu, isango, iglowubhu kunye neevalvu zokukhangela zinokufumaneka kwizityalo ngokunjalo.

Inkonzo yokwahlula igesi ibandakanya ukwahlula igesi kwizinto zayo ezisisiseko. Ngokomzekelo, iindlela zokwahlula umoya zivelisa initrogen, ioksijini, i-helium kunye nezinye iigesi zomkhondo. Ubume bobushushu obuphantsi kakhulu benkqubo buthetha ukuba kufuneka iivalve ezininzi ze-cryogenic.

Zombini izityalo ze-LNG kunye ne-gas zokwahlula zineevalve ezisezantsi zobushushu ekufuneka zihlale zisebenza kwezi meko ze-cryogenic. Oku kuthetha ukuba inkqubo yokupakisha i-valve kufuneka iphakanyiswe kude ne-low-temperature fluid ngokusebenzisa i-gas okanye ikholamu yokunciphisa. Le kholamu yegesi ithintela ulwelo ekwenzeni ibhola yomkhenkce ejikeleze indawo yokupakisha, nto leyo enokuthintela isiqu sevalve ekujikeni okanye ekunyukeni.

IZAKHIWO ZOKURHWEBA
Izakhiwo zorhwebo zisingqongile kodwa ngaphandle kokuba sinikela ingqalelo ethe kratya njengoko zisakhiwa, asinalo nofifi oluncinane malunga nobuninzi bemithambo yolwelo efihlwe kwiindonga zazo zobume, iglasi nentsimbi.

Into eqhelekileyo kwisakhiwo ngasinye ngamanzi. Zonke ezi zakhiwo ziqulethe iindidi zeenkqubo zombhobho ezithwele indibaniselwano eninzi ye-hydrogen / i-oxygen compound ngendlela yamanzi okusela, amanzi amdaka, amanzi ashushu, amanzi angwevu kunye nokukhusela umlilo.

Ukusuka kumbono wokusinda kwisakhiwo, iinkqubo zomlilo zibaluleke kakhulu. Ukhuseleko lomlilo kwizakhiwo luphantse lutyiswe kwaye luzaliswe ngamanzi acocekileyo. Ukuze iinkqubo zamanzi omlilo zisebenze, kufuneka zithembeke, zibe noxinzelelo olwaneleyo kwaye zibe lula kwindawo yonke yesakhiwo. Ezi nkqubo ziyilelwe ukunika amandla ngokuzenzekelayo kwimeko yomlilo.
Izakhiwo eziphakamileyo zifuna inkonzo efanayo yoxinzelelo lwamanzi kwimigangatho ephezulu njengoko imigangatho esezantsi ngoko ke iimpompo ezinoxinzelelo oluphezulu kunye nemibhobho kufuneka isetyenziswe ukufumana amanzi phezulu. Iinkqubo zemibhobho zidla ngokuba yiClass 300 okanye 600, kuxhomekeke kubude besakhiwo. Zonke iintlobo zeevalvu zisetyenziswa kwezi zicelo; nangona kunjalo, uyilo lwevalvu kufuneka luvunywe yi-Underwriters Laboratories okanye iFactory Mutual ngenkonzo ephambili yomlilo.

Iiklasi ezifanayo kunye neentlobo zeevalve ezisetyenziselwa iivalve zenkonzo yomlilo zisetyenziselwa ukuhanjiswa kwamanzi okusela, nangona inkqubo yokuvunywa ingekho ngqongqo.
Iinkqubo zokupholisa umoya zorhwebo ezifumaneka kwizakhiwo zoshishino ezinkulu ezifana nezakhiwo zeofisi, iihotele kunye nezibhedlele zihlala zibekwe embindini. Baneyunithi enkulu yokupholisa okanye ibhoyila yokupholisa okanye ukufudumeza ulwelo olusetyenziselwa ukuhambisa ingqele okanye ubushushu obuphezulu. Ezi nkqubo zihlala kufuneka ziphathe izikhenkcezisi ezifana ne-R-134a, i-hydro-fluorocarbon, okanye kwimeko yeenkqubo zokufudumeza ezinkulu, umphunga. Ngenxa yobungakanani obubambeneyo bebhabhathane kunye neevalvu zebhola, ezi ntlobo ziye zaziwa kwiinkqubo zokupholisa ze-HVAC.

Kwicala lomphunga, ezinye iivalvu zekota ziye zangena zisebenza, ukanti iinjineli ezininzi zemibhobho zisaxhomekeke kumgca wesango kunye neevalvu zeglowubhu, ngakumbi ukuba imibhobho ifuna iziphelo ze-butt-weld. Kwezi zicelo zomphunga ziphakathi, intsimbi ithathe indawo yentsimbi ngenxa yentsimbi yokuwelda.

Ezinye iinkqubo zokufudumeza zisebenzisa amanzi ashushu endaweni yomphunga njengolwelo lokudlulisa. Ezi nkqubo zihanjiswa kakuhle ngeevalvu zobhedu okanye zentsimbi. Ibhola ehlala i-quarter-turn resilient-seat kunye ne-butterfly valves zithandwa kakhulu, nangona ezinye ze-linear designs zisasetyenziswa.

ISIPHELO
Nangona ubungqina bezicelo zevalve ezikhankanywe kweli nqaku zisenokungabonakali ngexesha lokuya kwi-Starbucks okanye kwindlu kagogo, ezinye iivalve ezibaluleke kakhulu zihlala zikufuphi. Kukho neevalvu kwi-injini yenqwelo-mafutha esetyenziselwa ukufika kwezo ndawo ezifana nezo zikwi-carburetor ezilawula ukuhamba kwamafutha e-injini kunye nalawo akwi-injini alawula ukuhamba kwepetroli kwiipiston nokuphuma kwakhona. Kwaye ukuba ezo zivalo azisondele ngokwaneleyo kubomi bethu bemihla ngemihla, qwalasela inyaniso yokuba iintliziyo zethu zibetha rhoqo ngezixhobo ezine ezibalulekileyo zokulawula ukuhamba.

Lo ngomnye nje umzekelo wenyaniso yokuba: iivalvu zikwindawo yonke. VM
Icandelo II leli nqaku libandakanya amashishini ongezelelweyo apho iivalve zisetyenziswa. Yiya ku-www.valvemagazine.com ukufunda malunga nepulp & nephepha, usetyenziso lwaselwandle, amadama kunye namandla ombane owenziwe ngamanzi, ilanga, intsimbi kunye nentsimbi, i-aerospace, i-geothermal, kunye nokwenza i-craft brewing kunye ne-distilling.

UGREG JOHNSON ungumongameli we-United Valve (www.unitedvalve.com) eHouston. Ungumhleli onegalelo kwi-VALVE Magazine, usihlalo odlulileyo weBhunga lokuLungisa iiValve kunye nelungu langoku lebhodi yeVRC. Ukwasebenza kwiKomiti yeMfundo noQeqesho ye-VMA, ungusekela sihlalo weKomiti yoNxibelelwano ye-VMA kwaye ungumongameli odlulileyo we-Manufacturers Standardization Society.