Ama-valve alimele ohlelweni oluphuthumayo lwesikhungo samandla enuzi saseLaSalle

Kule ntwasahlobo, i-NRC Special Inspection Team (SIT) yenze ukuhlola kwe-LaSalle Nuclear Power Plant ukuze kuphenywe imbangela yokwehluleka kwamavalvu futhi kuhlolwe ukuphumelela kwezinyathelo zokulungisa ezithathiwe. Amayunithi amabili e-Exelon Generation Company's LaSalle County Nuclear Power Plant, cishe amamayela angu-11 eningizimu-mpumalanga ye-Ottawa, e-Illinois, ayiziphehlisi zamanzi abilayo (BWR) ezaqala ukusebenza ekuqaleni kwawo-1980. Nakuba ama-BWR amaningi asebenza e-United States eyi-BWR/4 enomklamo wokuqukatha we-Mark I, amadivayisi "amasha" we-LaSalle asebenzisa i-BWR/5 ngomklamo wokuqukatha we-Mark II. Umehluko omkhulu kulokhu kubuyekezwa ukuthi nakuba i-BWR/4 isebenzisa umjovo oqhutshwa umusi ophezulu we-high-pressure coolant injection (HPCI) ukuze inikeze amanzi okupholisa okungeziwe ku-reactor core lapho ipayipi elincane elixhuma umkhumbi we-reactor liphuka, i-BWR/5 isebenzisa isistimu ye-High Pressure Core Spray (HPCS) eshayelwa yimoto ukuze kuzuzwe le ndima yokuphepha. Ngo-February 11, 2017, ngemva kokugcinwa kwesistimu nokuhlolwa, abasebenzi bazama ukugcwalisa kabusha uhlelo lwe-2 high-pressure core injection (HPCS). Ngaleso sikhathi, i-reactor ye-Unit 2 yayivaliwe ngenxa yokuphazamiseka kokugcwaliswa kukaphethiloli, futhi isikhathi sokuphumula sasetshenziselwa ukuhlola amasistimu ezimo eziphuthumayo, njengohlelo lwe-HPCS. Uhlelo lwe-HPCS luvamise ukuba kumodi yokulinda ngesikhathi sokusebenza kwe-reactor. Uhlelo lufakwe iphampu eshayelwa ngemoto engahlinzeka ngokugeleza okungeziwe okuklanyelwe okungamamalitha ayi-7,000 ngomzuzu womkhumbi we-reactor. Iphampu ye-HPCS idonsa amanzi ethangini lesiqukathi esiku-container. Uma ipayipi lobubanzi obuncane obuxhunywe kumkhumbi we-reactor liphuka, amanzi okupholisa azovuza, kodwa ukucindezela ngaphakathi komkhumbi we-reactor kusetshenziswa uchungechunge lwezinhlelo eziphuthumayo zokucindezela okuphansi (okungukuthi, ukukhipha ukushisa kwemfucumfucu kanye nephampu yesifutho ewumgogodla wokucindezela ophansi. ). Amanzi agelezayo aphuma ekugcineni kwepayipi eliphukile akhishelwa ethangini lokucindezela ukuze aphinde asetshenziswe. Iphampu ye-HPCS eshayelwa ngenjini inganikwa amandla kusuka kugridi engaphandle kwesayithi uma itholakala, noma emshinini wokuphehla udizili ophuthumayo osendaweni lapho igridi ingatholakali. Abasebenzi abakwazanga ukugcwalisa ipayipi phakathi kwevalve yomjovo we-HPCS (1E22-F004) nomkhumbi we-reactor. Bathole ukuthi i-disc ihlukaniswe nesiqu se-valve yesango elikabili-clapper eyenziwe ngu-Anchor Darling, evimba indlela yokugeleza yepayipi lokugcwalisa. Ivalvu yomjovo we-HPCS iyivalvu kagesi evamise ukuvaleka evuleka lapho uhlelo lwe-HPCS luqalwa ukuze lunikeze umgudu wamanzi wokuzilungisa ukuze afinyelele umkhumbi we-reactor. I-motor isebenzisa i-torque ukuzungezisa isiqu se-valve esivunguzayo ukuze iphakamise (ivule) noma yehlise (ivale) idiski kuvalvu. Uma yehliswe ngokugcwele, i-disc izovimbela ukugeleza nge-valve. Lapho i-valve flap iphakanyiswa ngokugcwele, amanzi ageleza ku-valve ageleza ngaphandle kokuvinjelwa. Njengoba i-disc ihlukaniswe nesiqu se-valve endaweni ephansi ngokugcwele, i-motor ingase ijikeleze i-valve stem njengokungathi iphakamisa i-disc, kodwa i-disc ngeke ihambe. Abasebenzi bathatha izithombe zamadiski ahlukene kabili ngemuva kokukhipha isembozo sevalvu (umkhono) wevalvu (Umfanekiso 3). Unqenqema olungezansi lwesiqu luvela phakathi nendawo ephezulu yesithombe. Ungabona ama-disc amabili kanye nezinsimbi zomhlahlandlela eduze kwawo (uma uxhunywe esiqwini se-valve). Abasebenzi bashintsha izingxenye zangaphakathi zevalvu yomjovo we-HPCS bafaka izingxenye eziklanywe kabusha umphakeli, futhi baphinda bagcizelela iyunithi enguNo. I-Tennessee River Basin Authority ithumele umbiko ku-NRC ngoJanuwari 2013 ngaphansi kwe-10 CFR Ingxenye 21 mayelana nokukhubazeka ku-Anchor Darling i-double disk gate valve ohlelweni lomjovo olunomfutho ophezulu wokupholisa we-Browns Ferry Nuclear Power Plant. Ngenyanga elandelayo, umphakeli wamavalvu wathumela umbiko we-10 CFR Ingxenye 21 ku-NRC mayelana nenkinga yokuklama i-valve yesango le-Anchor Darling ye-double disc, engabangela isiqu se-valve ukuthi sihlukane nediski. Ngo-April 2013, IQembu Labanikazi be-Boiling Water Reactor lakhipha umbiko ngombiko weNgxenye 21 kumalungu alo kanye nezindlela ezinconyiwe zokuqapha ukusebenza kwamavalvu athintekile. Izincomo zihlanganisa ukuhlolwa kokuxilonga nokuqapha ukujikeleza kwesiqu. Ngo-2015, abasebenzi benza izivivinyo zokuxilonga ezinconyiwe ku-HPCS injection valve 2E22-F004 eLaSalle, kodwa azikho izinkinga zokusebenza ezitholakele. Ngomhla ziyisi-8 kuNhlolanja wezi-2017, abasebenzi basebenzise umhlahlandlela wokuqapha ukujikeleza kwe-stem ukuze banakekele futhi bahlole i-HPCS injection valve 2E22-F004. Ngo-April 2016, iqembu labanikazi be-reactor yamanzi abilayo labuyekeza umbiko wabo ngokusekelwe olwazini olunikezwe umnikazi wendawo yokuphehla ugesi. Abasebenzi bahlakaze ama-valve angama-26 Anchor Darling ama-double disc angena engozini bathola ukuthi angu-24 awo anezinkinga. Ngo-Ephreli 2017, i-Exelon yazisa i-NRC ukuthi i-HPCS injection valve 2E22-F004 ihlulekile ngenxa yokuhlukaniswa kwe-valve stem kanye ne-disc. Phakathi namasonto amabili, ithimba lokuhlola elikhethekile (SIT) eligunyazwe yi-NRC lafika eLaSalle ukuze liphenye imbangela yokuhluleka kwe-valve futhi lihlole ukuphumelela kwezinyathelo zokulungisa ezithathiwe. I-SIT ibuyekeze ukuhlolwa kwe-Exelon kwemodi yokwehluleka kwevalvu yomjovo we-Unit 2 HPCS. I-SIT ivumile ukuthi ingxenye ethile ngaphakathi kwe-valve iqhume ngenxa yamandla amakhulu. Ingxenye ephukile ibangela ukuthi ukuxhumana phakathi kwe-valve stem kanye ne-intervertebral disc kuqhubeke kungahambi kahle, kuze kube yilapho i-intervertebral disc ekugcineni ihlukana nesiqu se-valve. Umphakeli uhlele kabusha isakhiwo sangaphakathi se-valve ukuxazulula inkinga. I-Exelon yazisa i-NRC ngo-June 2, 2017 ukuthi ihlela ukulungisa amanye ama-valve amasango e-Anchor Darling ahlobene nokuphepha angu-16 angaba sengozini yalokhu kwehluleka ngesikhathi sokuphazamiseka okulandelayo kokufakwa kukaphethiloli kwamayunithi amabili e-LaSalle. indlela. I-SIT ibuyekeze izizathu ze-Exelon zokulinda ukulungisa lawa ma-valve angu-16. I-SIT ikholelwa ukuthi isizathu sinengqondo, ngaphandle kokukodwa-ivalvu yomjovo we-HCPS kuYunithi 1. I-Exelon ilinganisele inani lemijikelezo yevalvu yomjovo we-HPCS yeYunithi 1 kanye neYunithi 2. Ivalvu Yeyunithi 2 kwakuyinto yokuqala efakwe ekuqaleni. 1980s, ngenkathi i-valve ye-Unit 1 yashintshwa ngo-1987 ngemva kokulimala ngenxa yezinye izizathu. U-Exelon wagomela ngokuthi inani elikhulu lokushaywa kwama-valve kuyunithi 2 lichaze ukwehluleka kwalo futhi kwaba nesizathu sokulinda kuze kube yilapho kuphazanyiswa ukufakwa kukaphethiloli okulandelayo ukuze kuxazululwe inkinga ye-valve yeyunithi 1. I-SIT icaphune izici ezifana nomehluko ongaziwa wokuhlola wangaphambi kokusebenza phakathi kwamayunithi, kancane. umehluko wokuklama onemiphumela engaziwa, izici zamandla ezinto ezibonakalayo ezingaqinisekile, kanye nomehluko ongaqinisekile ekugqokeni kwe-valve kuya ekugqokeni kwentambo ye-wedge, futhi waphetha ngokuthi "lena "inkinga yesikhathi" esikhundleni sokuthi "Uma" 1E22-F004 I-valve izohluleka uma kukhona akukho ukwehluleka esikhathini esizayo Ngamanye amazwi, i-SIT ayizange ithenge ukuhlolwa okubambezelekile kwe-valve yeyunithi 1 i-Exelon ivale i-LaSalle Unit 1 ngo-June 22, 2017 ukuze ithathe indawo yezingxenye zangaphakathi ze-HPCS valve 1E22-F004 Amanani we-torque athuthukiswe yi-Exelon yama-motor ama-valve omjovo we-HPCS 1E22-F004 kanye ne-2E22-F004 aphule i-10 CFR Ingxenye 50, Isithasiselo B, I-Standard III, Ukulawulwa Kwedizayini i-Exelon ithatha ukuthi isiqu se-valve iyisixhumanisi esibuthakathaka, futhi isungula a inani le-torque ye-motor elingafaki isiqu se-valve kungcindezi eyeqile. Kodwa isixhumanisi esibuthakathaka siphenduke enye ingxenye yangaphakathi. Inani le-torque ye-motor elisetshenziswa yi-Exelon libeka ingxenye ngaphansi kokucindezeleka okukhulu, okubangela ukuba iphuke futhi idiski ihlukane nesiqu se-valve. I-NRC inqume ukwephulwa komthetho njengokwephulwa okuqinile kweleveli III okusekelwe ekuhlulekeni kwevalvu okuvimbele isistimu ye-HPCS ekwenzeni imisebenzi yayo yokuphepha (kusistimu yamaleveli amane, ileveli I inzima kakhulu). Kodwa-ke, i-NRC yasebenzisa ukuqonda kwayo ngokomthetho ngokuvumelana nenqubomgomo yayo yokugcinwa komthetho futhi ayizange ishicilele ukwephulwa komthetho. I-NRC inqume ukuthi iphutha ledizayini yevalvu lalicashe kakhulu ukuthi i-Exelon ibone kusengaphambili futhi ilungise ngaphambi kokuhluleka kwevalvu Yeyunithi 2. U-Exelon ubukeke emuhle kakhulu kulo mcimbi. Amarekhodi e-SIT ye-NRC abonisa ukuthi i-Exelon iyawazi umbiko weNgxenye 21 owenziwe yi-Tennessee Valley Authority kanye nomphakeli wamavalvu ngo-2013. Abakwazanga ukusebenzisa lokhu kuqwashisa ukuze bakhombe futhi balungise izinkinga zamavalvu omjovo we-Unit 2 HPCS njengenkomba yokusebenza kwabo okubi. . Phela, basebenzise izinyathelo ezinconywe iQembu Lomnikazi Wereactor Yamanzi Abilayo ngemibiko emibili yeNgxenye 21. Ububi bukhona kumhlahlandlela, hhayi ukusetshenziswa kwe-Exelon kuwo. Okuwukuphela kwephutha ekusingatheni kwe-Exelon lolu daba ukuthi isizathu sokusebenzisa i-Unit 1 sasibuthakathaka ngaphambi kokuhlola ukuthi ivalvu yomjovo we-HPCS yonakele yini noma yonakele, kwaze kwaba yilapho ukufakwa kukaphethiloli kwayo okulandelayo kuphazamiseka. Nokho, i-SIT ye-NRC yasiza u-Exelon wanquma ukusheshisa uhlelo. Ngenxa yalokho, iYunithi 1 yavalwa ngoJuni 2017 ukuze ithathelwe indawo i-valve yeYunithi 1 esengozini. I-NRC ibukeke iyinhle kakhulu kulo mcimbi. Akukhona nje ukuthi i-NRC iholele i-Exelon endaweni ephephile ye-LaSalle Unit 1, kodwa i-NRC iphinde yanxusa yonke imboni ukuthi ixazulule le nkinga ngaphandle kokulibaziseka okungenangqondo. I-NRC ikhiphe isaziso solwazi sika-2017-03 kubanikazi befekthri ngomhla ka-15 Juni, 2017, mayelana nokukhubazeka kwedizayini ye-Anchor Darling double disc valve valve kanye nemikhawulo yezinkombandlela zokuqapha ukusebenza kwama-valve. I-NRC ibambe uchungechunge lwemihlangano yomphakathi nabamele izimboni nabahlinzeki ngamavalvu ngenkinga nezisombululo zayo. Omunye wemiphumela yalokhu kusebenzisana ukuthi imboni ibhale uchungechunge lwezinyathelo, uhlelo lokuxazulula olunomnqamulajuqu okuhlosiwe ngaphambi komhla zingama-31 kuZibandlela wezi-2017, kanye nophenyo olumayelana nokusetshenziswa kwamavalvu esango e-Anchor Darling e-double disc kumandla enuzi ase-US. izitshalo. Uphenyo lubonisa ukuthi cishe ama-valve amasango e-700 Anchor Darling double disc gate (AD DDGV) asetshenziswa ezikhungweni zamandla enuzi e-United States, kodwa angu-9 kuphela anezici zengozi ephezulu/emaphakathi, amavalvu ane-stroke eminingi. (Ama-valve amaningi ane-stroke eyodwa, ngoba umsebenzi wawo wokuphepha ukuvala lapho evuliwe, noma avuleke lapho evaliwe. Ama-valve ane-multi-stroke angabizwa ngokuthi avulekile futhi avaliwe, futhi angase avuleke futhi avalwe izikhathi eziningi ukuze afeze umsebenzi wawo wokuphepha.) imboni isenayo isikhathi sokubuyisela ukwehluleka kwayo ekunqobeni, kodwa i-NRC ibonakala ikulungele ukubona imiphumela efike ngesikhathi nangempumelelo kulolu daba. Thumela i-SMS ethi "SAYENSI" ku-662266 noma ubhalise ku-inthanethi. Bhalisa noma uthumele i-SMS ethi "SAYENSI" ku-662266. Izindleko ze-SMS nedatha zingakhokhiswa. Umbhalo uyeka ukuphuma. Asikho isidingo sokuthenga. 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