1 Amaphuzu abalulekile okukhethwa kwevalvu

1.1 Cacisa inhloso yevalvu emshinini noma ocingweni

Ukunquma izimo zokusebenza ze-valve: uhlobo lwendawo esebenzayo, ingcindezi yokusebenza, izinga lokushisa lokusebenza kanye nendlela yokulawula ukusebenza, njll.;

1.2 Khetha kahle uhlobo lwevalvu

Ukukhetha okulungile kohlobo lwevalvu kusekelwe ekubambeni komklami yonke inqubo yokukhiqiza nezimo zokusebenza. Lapho ekhetha uhlobo lwevalvu, umklami kufanele aqale abe yingcweti yezimpawu zesakhiwo nokusebenza kwevalvu ngayinye;

1.3 Nquma ukuphela kokuxhumana kwevalvu

Phakathi koxhumano oluluchungechunge, uxhumano lwe-flange nokuxhumeka kokuphela kwe-welding, okubili kokuqala kusetshenziswa kakhulu. Ama-valve anemicu ikakhulukazi ama-valve anobubanzi obuncane obungaphansi kuka-50mm. Uma ubukhulu bobubanzi bukhulu kakhulu, ukufakwa nokubekwa uphawu koxhumano kunzima kakhulu. Ama-valve axhunywe nge-flange afaneleka kakhulu ukufaka nokuhlakazwa, kodwa ayasinda futhi abiza kakhulu kunama-valve ane-threaded, ngakho-ke afaneleka ukuxhumeka kwamapayipi obubanzi obuhlukahlukene kanye nezingcindezi. Izixhumanisi zokushisela zifanele izimo zomthwalo osindayo futhi zithembeke kakhulu kunoxhumo lwe-flange. Kodwa-ke, kunzima ukuhlukanisa nokufaka kabusha ama-valve axhunywe ngokushisela, ngakho-ke ukusetshenziswa kwawo kunqunyelwe ezikhathini lapho ngokuvamile kungasebenza khona ngokwethembeka isikhathi eside, noma izimo zokusebenzisa zinzima futhi izinga lokushisa liphezulu;

1.4 Ukukhethwa kwezinto zevalvu

Ngaphezu kokucabangela izakhiwo ezingokoqobo (izinga lokushisa, ingcindezi) kanye nezakhiwo zamakhemikhali (ukugqwala) kwendawo yokusebenza, ukuhlanzeka kwendawo (noma ngabe kunezinhlayiya eziqinile) kufanele kube kahle lapho kukhethwa izinto zegobolondo le-valve, izingxenye zangaphakathi kanye indawo yokubeka uphawu. Ukwengeza, imithethonqubo efanele yombuso kanye nomnyango wabasebenzisi kufanele kubhekiswe kuyo. Ukukhetha okulungile nokunengqondo kwezinto ze-valve kungathola impilo yesevisi eyonga kakhulu kanye nokusebenza okungcono kakhulu kwe-valve. I-oda lokukhetha lezinto ezisetshenziswayo ze-valve yilezi: insimbi engagqwali ye-iron-carbon steel-stainless, kanye ne-oda lokukhetha lezinto ezisetshenziswayo zokuvala uphawu: i-rubber-copper-alloy steel-F4;

1.5 Abanye

Ukwengeza, izinga lokugeleza kanye nezinga lokucindezela koketshezi olugeleza ku-valve kufanele kunqunywe, futhi i-valve efanele kufanele ikhethwe kusetshenziswa ulwazi olukhona (njengamakhathalogi omkhiqizo we-valve, amasampula omkhiqizo we-valve, njll.).

2 Isingeniso samavavu Avamile

Kunezinhlobo eziningi zama-valve, futhi izinhlobo ziyinkimbinkimbi. Izinhlobo eziyinhloko ziyiama-valve esango, ama-stop valves, ama-throttle valves,izivalo uvemvane, ama-valve amapulaki, ama-valve amabhola, ama-valve kagesi, ama-diaphragm valve, ama-sheke ama-valve, ama-valve okuphepha, ama-valve okunciphisa ingcindezi,izicupho ze-steam nama-valve wokuvala izimo eziphuthumayo,phakathi kwazo okuvame ukusetshenziswa ama-valve esango, ama-stop valves, ama-throttle valves, ama-plug valves, ama-butterfly valve, ama-ball valve, ama-sheke valve, nama-diaphragm valve.

2.1 Ivalvu yesango

I-valve yesango i-valve umzimba wayo wokuvula nokuvala (i-valve plate) ishayelwa isiqu se-valve futhi yehla inyuka ihambisana nendawo yokuvala yesihlalo se-valve, engaxhuma noma inqamule indlela yoketshezi. Uma kuqhathaniswa ne-valve yokumisa, i-valve yesango inokusebenza okungcono kokuvala, ukumelana noketshezi oluncane, umzamo omncane ekuvuleni nasekuvaleni, futhi inokusebenza okuthile kokulungisa. Ingenye yama-valve okuvala asetshenziswa kakhulu. Ukungalungi ubukhulu obukhulu, isakhiwo esiyinkimbinkimbi kune-valve yokumisa, ukuguga kalula kwendawo yokuvala, nokugcinwa okunzima. Ngokuvamile ayifaneleki ukuphusha. Ngokwesimo sentambo esiqwini se-valve yesango, ingahlukaniswa ngezinhlobo ezimbili: uhlobo lwe-stem olukhulayo kanye nohlobo lwe-stem olufihliwe. Ngokwezici zesakhiwo sepuleti lesango, lingahlukaniswa ngezinhlobo ezimbili: uhlobo lwe-wedge kanye nohlobo oluhambisanayo.

2.2 Ivalvu yokumisa

I-valve yokumisa i-valve yokuvala eyehlayo, lapho izingxenye zokuvula nokuvala (i-valve disc) zishayelwa isiqu se-valve ukuhamba phezulu naphansi eduze kwe-eksisi yesihlalo se-valve (indawo yokuvala). Uma kuqhathaniswa ne-valve yesango, inokusebenza okuhle kokulungisa, ukusebenza kahle kokuvala uphawu, isakhiwo esilula, ukukhiqiza nokugcinwa okulula, ukumelana noketshezi olukhulu, kanye nenani eliphansi. Kuyivalvu yokusika esetshenziswa kakhulu, ejwayele ukusetshenziselwa amapayipi aphakathi nendawo namancane.

2.3 I-valve yebhola

Izingxenye ezivulayo nezivalayo ze-valve yebhola ziyiziyingi ezinezimbobo eziyindilinga, futhi i-sphere izungeza nesiqu se-valve ukuze ibone ukuvuleka nokuvalwa kwevalvu. I-valve yebhola inesakhiwo esilula, ukushintsha okusheshayo, ukusebenza okulula, usayizi omncane, isisindo esilula, izingxenye ezimbalwa, ukumelana noketshezi oluncane, ukubeka uphawu oluhle, nokugcinwa okulula.

2.4 I-valve ye-throttle

Ngaphandle kwe-valve disc, i-throttle valve inesakhiwo esifanayo ne-valve yokumisa. I-valve disc yayo iyingxenye ye-throttling, futhi izimo ezihlukene zinezici ezihlukene. Ububanzi besihlalo se-valve akufanele bube bukhulu kakhulu, ngoba ukuphakama kwayo kokuvula kuncane futhi izinga lokugeleza eliphakathi liyakhula, ngaleyo ndlela kusheshisa ukuguguleka kwediski ye-valve. I-valve ye-throttle inobukhulu obuncane, isisindo esincane, nokusebenza okuhle kokulungisa, kodwa ukunemba kokulungiswa akuphakeme.

2.5 I-valve yokuxhuma

I-valve yepulaki isebenzisa umzimba wepulaki onembobo ephumela njengengxenye yokuvula neyokuvala, futhi umzimba wepulaki uzungezisa nesiqu se-valve ukuze kuzuzwe ukuvula nokuvala. I-valve yepulaki inesakhiwo esilula, ukuvula nokuvala ngokushesha, ukusebenza okulula, ukumelana noketshezi oluncane, izingxenye ezimbalwa, nesisindo esincane. Ama-valve okuxhuma atholakala ngezinhlobo eziqondile, ezinezindlela ezintathu, nezine. Ama-valve amapulaki aqondile asetshenziselwa ukusika i-medium, futhi ama-valve amapulaki anezindlela ezintathu nanezindlela ezine asetshenziselwa ukushintsha isiqondiso se-medium noma ukuguqula okuphakathi.

2.6 Ivalve yovemvane

Ivalve uvemvane ipuleti uvemvane elizungeza 90° lizungeze i-eksisi engashintshi emzimbeni wevalvu ukuze kuqedelwe umsebenzi wokuvula nokuvala. I-valve yovemvane incane ngosayizi, ilula ngesisindo, ilula ngokwakheka, futhi inezingxenye ezimbalwa kuphela.

Futhi ingavulwa ngokushesha futhi ivalwe ngokuzungezisa i-90 °, futhi kulula ukuyisebenzisa. Uma i-valve uvemvane isendaweni evuleke ngokugcwele, ubukhulu bepuleti uvemvane yibo kuphela ukumelana lapho okuphakathi kugeleza emzimbeni wevalvu. Ngakho-ke, ukwehla kokucindezela okukhiqizwa yi-valve kuncane kakhulu, ngakho kunezici ezinhle zokulawula ukugeleza. Ama-valve ovemvane ahlukaniswe abe izinhlobo ezimbili zokuvala: uphawu oluthambile olunwebekayo kanye nophawu oluqinile lwensimbi. Kumavalvu anwebekayo ophawu, indandatho yokuvala ingashumeka emzimbeni wevalvu noma ixhunywe kuma-periphery wepuleti lovemvane. Isebenza kahle ngokuvala futhi ingasetshenziselwa ukudonsa umoya, kanye namapayipi evacuum aphakathi nendawo kanye nemidiya ebolayo. Amavalvu anezigxivizo zensimbi ngokuvamile anesikhathi eside sokusebenza kunamavalvu anezimpawu ezinwebekayo, kodwa kunzima ukufeza ukuvaleka okuphelele. Ngokuvamile zisetshenziswa ezikhathini lapho ukugeleza nokwehla kwengcindezi kuhluka kakhulu futhi kudingeka ukusebenza kahle kwe-throttling. Izigxivizo zensimbi zingakwazi ukuzivumelanisa nezinga lokushisa eliphakeme lokusebenza, kuyilapho izigxivizo ezinwebekayo zinesici sokunqunyelwa izinga lokushisa.

2.7 Hlola i-valve

I-valve yokuhlola iyi-valve engavimbela ngokuzenzakalelayo ukugeleza koketshezi. I-valve disc ye-valve yokuhlola ivula ngaphansi kwesenzo sokucindezela uketshezi, futhi uketshezi lugeleza lusuka ohlangothini lokungena luye ohlangothini lokuphuma. Lapho ingcindezi ehlangothini lokungena iphansi kunaleyo ehlangothini lokuphuma, i-disc ye-valve ivala ngokuzenzakalelayo ngaphansi kwesenzo sezici ezifana nomehluko we-fluid pressure kanye namandla ayo adonsela phansi ukuze kuvinjwe ukugeleza koketshezi emuva. Ngokwefomu lesakhiwo, ihlukaniswe i-valve yokuhlola i-lift kanye ne-swing check valve. I-valve yokuhlola i-lift inokuvalwa okungcono kune-valve yokuhlola i-swing kanye nokumelana noketshezi okukhulu. Ukuze uthole imbobo yokudonsa yepayipi yokudonsa ipompo, i-valve yonyawo kufanele ikhethwe. Umsebenzi wayo: ukugcwalisa ipayipi lokungena kwepompo ngamanzi ngaphambi kokuqala iphampu; ukugcina ipayipi lokungena kanye nomzimba wokumpompa ugcwele amanzi ngemva kokumisa iphampu ukulungiselela ukuqala kabusha. I-valve yonyawo ngokuvamile ifakwa kuphela epayipini elime mpo endaweni yokungena yepompo, futhi okuphakathi kugeleza ukusuka phansi kuye phezulu.

2.8 I-valve ye-diaphragm

Ingxenye evulayo nevalayo ye-valve ye-diaphragm iyi-diaphragm yerabha, ehlanganiswe phakathi komzimba we-valve kanye nesembozo se-valve.

Ingxenye ephumayo ye-diaphragm igxilile esiqwini se-valve, futhi umzimba we-valve ufakwe irabha. Njengoba i-medium ingangeni emgodini wangaphakathi wekhava ye-valve, isiqu se-valve asidingi ibhokisi lokugxusha. I-valve ye-diaphragm inesakhiwo esilula, ukusebenza kahle kokuvala, ukugcinwa okulula, nokumelana noketshezi oluphansi. Ama-valve e-diaphragm ahlukaniswe ngohlobo lwe-weir, uhlobo oluqondile, uhlobo lwe-engeli yesokudla kanye nohlobo lwamanje oluqondile.

3 Iziyalezo ezijwayelekile zokukhetha i-valve

3.1 Imiyalo yokukhetha ivalvu yesango

Ngokuvamile, ama-valve esango kufanele akhethwe kuqala. Ngaphezu kwe-steam, uwoyela kanye neminye imidiya, ama-valve amasango nawo afaneleka kumidiya equkethe izinto eziqinile eziyimbudumbudu kanye ne-viscosity ephezulu, futhi afanele ama-valve okukhipha umoya kanye nezinhlelo ze-vacuum eziphansi. Ukuze uthole imidiya enezinhlayiya eziqinile, umzimba we-valve wesango kufanele ube nembobo yokuhlanza eyodwa noma ezimbili. Ukuze uthole imidiya yokushisa ephansi, i-valve yesango ekhethekile yokushisa ephansi kufanele ikhethwe.

3.2 Misa imiyalelo yokukhetha ivalvu

I-valve yokumisa ifanele amapayipi anezidingo eziphansi zokumelana noketshezi, okungukuthi, ukulahlekelwa kwengcindezi akucatshangelwa kakhulu, kanye namapayipi noma amadivaysi anemidiya yokushisa ephezulu kanye ne-high-pressure. Ilungele amapayipi omusi namanye abezindaba ane-DN <200mm; ama-valve amancane angasebenzisa ama-stop valves, njengama-valve enaliti, ama-instrument valve, ama-sampling valves, ama-valve gauge gauge, njll.; ama-valve amisayo anokulawula ukugeleza noma ukulawulwa kwengcindezi, kodwa ukunemba kokulawula akuphakeme, futhi ububanzi bepayipi buncane uma kuqhathaniswa, ngakho kufanele kukhethwe ama-valve okumisa noma ama-throttle valve; kuma-media anobuthi obukhulu, ama-valve avaliwe ane-bellows kufanele akhethwe; kodwa ama-valve okumisa akumele asetshenziselwe imidiya ene-viscosity ephezulu kanye nemidiya equkethe izinhlayiya okulula ukushona phansi, futhi akufanele asetshenziswe njengama-valve nama-valve okukhipha umoya kumasistimu e-vacuum aphansi.

3.3 Imiyalo yokukhetha ivalvu yebhola

Ama-valve ebhola afanele izinga lokushisa eliphansi, i-high-pressure, nemidiya ye-viscosity ephezulu. Ama-valve amaningi ebhola angasetshenziswa emithonjeni yezindaba enezinhlayiya eziqinile ezimisiwe, futhi angasetshenziselwa imidiya eyimpuphu kanye ne-granular ngokusho kwezidingo ezibonakalayo zophawu; ama-valve ebhola agcwele ishaneli awafaneleki ukulawulwa kokugeleza, kodwa afanele izikhathi ezidinga ukuvulwa nokuvala ngokushesha, okulungele ukunqanyulwa kwezimo eziphuthumayo ezingozini; ama-valve amabhola avame ukutuswa kumapayipi asebenza ngokuvala ngokuqinile, ukuguga, ukushwabana kwamashaneli, ukuvulwa nokuvala ngokushesha, ukunqanyulwa kwengcindezi ephezulu (umehluko omkhulu wengcindezi), umsindo ophansi, i-gasification phenomenon, i-torque encane yokusebenza, nokumelana noketshezi oluncane; ama-valve ebhola afanele izakhiwo zokukhanya, i-low-pressure cut-off, kanye nemidiya edlayo; ama-valve amabhola nawo angama-valve alungele kakhulu izinga lokushisa eliphansi kanye nemidiya ebanda kakhulu. Kuzinhlelo zamapayipi kanye namadivayisi wemidiya yezinga lokushisa eliphansi, ama-valve amabhola asezingeni eliphansi anezembozo zamavalvu kufanele akhethwe; uma usebenzisa ama-valve ebhola elintantayo, impahla yesihlalo se-valve kufanele ithwale umthwalo webhola kanye nendawo yokusebenza. Amavalvu ebhola anobubanzi obukhulu adinga amandla amakhulu ngesikhathi sokusebenza, futhi amavalvu ebhola e-DN≥200mm kufanele asebenzise ukudluliswa kwegiya lezikelemu; ama-valve ebhola angaguquki afaneleka ngezikhathi ezinamadayimitha amakhulu nezingcindezi eziphakeme; ngaphezu kwalokho, ama-valve amabhola asetshenziselwa amapayipi ezinto zenqubo ezinobuthi kakhulu kanye nemidiya evuthayo kufanele abe nezakhiwo ezingashi kanye ne-anti-static.

3.4 Imiyalo yokukhetha ye-Throttle Valve

Ama-valve e-throttle afaneleka ngezikhathi ezinokushisa okuphansi okuphakathi nokucindezela okuphezulu, futhi afanele izingxenye ezidinga ukulungisa ukugeleza nokucindezela. Azifanele imidiya ene-viscosity ephezulu futhi equkethe izinhlayiya eziqinile, futhi awafaneleki ama-valve okuhlukanisa.

3.5 Imiyalo Yokukhetha Yevaluvu Yepulagi

Ama-valve okuxhuma afanele izikhathi ezidinga ukuvulwa nokuvala ngokushesha. Ngokuvamile azifaneleki imidiya ye-steam neyezinga lokushisa eliphezulu. Zisetshenziselwa imidiya enezinga lokushisa eliphansi kanye ne-viscosity ephezulu, futhi ibuye ifanele imidiya enezinhlayiya ezimisiwe.

3.6 Imiyalo Yokukhetha Yevaluvu Yevemvane

Amavalvu ovemvane afanele izikhathi ezinobubanzi obukhulu (njenge-DN﹥600mm) kanye nezidingo ezimfushane zesakhiwo, kanye nezikhathi ezidinga ukulawulwa kokugeleza nokuvuleka nokuvala ngokushesha. Ngokuvamile zisetshenziselwa imidiya efana namanzi, uwoyela nomoya ocindezelwe onamazinga okushisa ≤80℃ nezingcindezi ≤1.0MPa; njengoba amavavu ovemvane anokuncipha kokucindezela okukhulu uma kuqhathaniswa namavalvu esango namabhola, amavalvu ovemvane afaneleka ezinhlelweni zamapayipi anezidingo zokulahlekelwa kwengcindezi exegezelayo.

3.7 Imiyalo Yokukhetha Yevaluvu Yokuhlola

Ama-valve okuhlola ngokuvamile afanelekela imidiya ehlanzekile, futhi ayifanele imidiya equkethe izinhlayiya eziqinile kanye ne-viscosity ephezulu. Uma i-DN≤40mm, kuhle ukusebenzisa i-valve yokuhlola yokuphakamisa (ivunyelwe kuphela ukufakwa kumapayipi avundlile); uma i-DN＝50～400mm, kuyatuseka ukuthi usebenzise ivalve yokuhlola ukuphakamisa ujika (ingafakwa kuwo womabili amapayipi avundlile naqondile. Uma ifakwe epayipini eliqondile, isiqondiso sokugeleza okuphakathi kufanele sisuke phansi siye phezulu); uma i-DN≥450mm, kuyancomeka ukusebenzisa i-valve yokuhlola i-buffer; lapho i-DN＝100～400mm, ivalve yokuhlola i-wafer nayo ingasetshenziswa; i-valve yokuhlola i-swing ingenziwa ibe yingcindezi yokusebenza ephezulu kakhulu, i-PN ingafinyelela ku-42MPa, futhi ingasetshenziswa kunoma iyiphi indawo yokusebenza nanoma yiluphi uhla lokushisa olusebenzayo ngokusho kwezinto ezahlukene zegobolondo nezimpawu. Okuphakathi nendawo ngamanzi, umusi, igesi, i-corrosive medium, uwoyela, umuthi, njll. Ibanga lokushisa eliphakathi nendawo liphakathi kuka -196～800℃.

3.8 Imiyalo yokukhetha ivalvu ye-diaphragm

Amavalvu e-diaphragm afanele uwoyela, amanzi, imidiya ene-asidi kanye nemidiya equkethe izinto ezimisiwe ezinezinga lokushisa elingaphansi kuka-200℃ kanye nokucindezela okungaphansi kuka-1.0MPa, kodwa hhayi kwizinyibilikisi eziphilayo nezixube eziqinile. Amavalvu e-diaphragm ohlobo lwe-Weir afanele imidiya ye-granular abrasive. Ithebula lesici sokugeleza kufanele lisetshenziselwe ukukhetha amavalvu e-diaphragm yohlobo lwe-weir. Ama-valve e-diaphragm aqondile afanele uketshezi lwe-viscous, ama-slurries kasimende kanye nemidiya ye-sedimentary. Ngaphandle kwezidingo ezithile, ama-valve e-diaphragm akufanele asetshenziswe emigqeni ye-vacuum kanye nezinto zokusebenza ze-vacuum.