Mbibi Valve na sistemụ mberede nke ụlọ ọrụ ike nuklia LaSalle

N'oge opupu ihe ubi a, NRC Special Inspection Team (SIT) mere nyocha nke LaSalle Nuclear Power Plant iji nyochaa ihe kpatara ọdịda valvụ ma nyochaa ịdị irè nke usoro mmezi. Nkeji abụọ nke Exelon Generation Company's LaSalle County Nuclear Power Plant, ihe dị ka kilomita 11 ndịda ọwụwa anyanwụ nke Ottawa, Illinois, bụ ndị na-eme mmiri na-esi mmiri (BWR) malitere ịrụ ọrụ na mmalite 1980s. N'agbanyeghị na ọtụtụ BWR na-arụ ọrụ na United States bụ BWR/4 na Mark I containment imewe, "ọhụrụ" LaSalle ngwaọrụ na-eji BWR/5 na Mark II imewe. Isi ihe dị iche na nyocha a bụ na ọ bụ ezie na BWR / 4 na-eji usoro ntụtụ na-eme ka ikuku ume ọkụ (HPCI) na-eme ka mmiri na-eme ka mmiri dị jụụ na isi reactor ma ọ bụrụ na obere ọkpọkọ ejikọrọ na ụgbọ mmiri reactor ruptures, ojiji nke BWR/5 Sistemụ ịgbasa oke nrụgide dị elu (HPCS) na-arụ ọrụ nchekwa a. Na February 11, 2017, mgbe nhazi usoro na nyocha, ndị ọrụ gbalịrị mejupụta usoro nke 2 high-pressure core spray (HPCS). N'oge ahụ, e mechiri reactor nke Unit 2 n'ihi nkwụsị nke mmanụ ụgbọala, na-eji oge nkwụsịtụ iji lelee usoro mberede, dị ka usoro HPCS. Sistemu HPCS na-anọkarị na ọnọdụ njikere n'oge arụ ọrụ reactor. Ejiri usoro a nwere mgbapụta moto na-anya nke nwere ike inye mgbakwunye mgbakwunye nke galọn 7,000 kwa nkeji maka ụgbọ mmiri na-ebugharị. Igwe mgbapụta HPCS na-adọta mmiri site na tank nke dị na njide. Ọ bụrụ na obere dayameta ọkpọkọ ejikọrọ na reactor arịa agbajikwa, ndị jụrụ oyi mmiri ga-erikpu, ma nrụgide n'ime reactor arịa a na-arụ ọrụ site a usoro nke ala-nrụgide mberede usoro (ie, n'efu okpomọkụ mwepu na ala-nrụgide isi ịgba mgbapụta). ). A na-ahapụ mmiri nke na-esi na njedebe ọkpọkọ gbajiri agbaji na tank nke nkwụsị maka ijikwa ya ọzọ. Enwere ike ịgbanye mgbapụta HPCS moto na-anya site na grid na-adịghị na saịtị mgbe ọ dị, ma ọ bụ site na igwe ọkụ diesel mberede na saịtị mgbe grid adịghị. Ndị ọrụ enweghị ike ijupụta ọkpọkọ n'etiti valvụ injection HPCS (1E22-F004) na ụgbọ mmiri reactor. Ha chọpụtara na e kewapụrụ diski ahụ site na valvụ ọnụ ụzọ ámá abụọ-clapper nke Anchor Darling mere, na-egbochi ụzọ mgbaba nke ọkpọkọ na-ejuputa. valvụ injection HPCS bụ valvụ eletrik mechiri emechi nke na-emepe mgbe usoro HPCS malitere inye ọwa maka mmiri etemeete iji ruo arịa reactor. The moto na-etinye torque iji tụgharịa spiral valvụ azuokokoosisi ibuli (emeghe) ma ọ bụ ala (n'imechi) diski na valvụ. Mgbe a na-agbadata nke ọma, diski ahụ ga-egbochi ntinye site na valvụ ahụ. Mgbe valvụ ahụ na-ebuli elu nke ọma, mmiri na-esi na valvụ ahụ na-aga n'enweghị ihe mgbochi. Ebe ọ bụ na diski ahụ kewapụrụ site na valvụ valvụ na-agbadata n'ụzọ zuru ezu, moto ahụ nwere ike ịtụgharị valvụ ahụ dị ka à ga-asị na ọ na-ebuli diski ahụ, ma diski ahụ agaghị agagharị. Ndị ọrụ were foto nke diski abụọ ahụ kewapụrụ iche mgbe ha wepụsịrị mkpuchi valvụ (aka aka) nke valvụ (Fig 3). Ọnụ ala nke osisi ahụ na-egosi na etiti elu nke foto a. Ị nwere ike ịhụ diski abụọ na okporo ụzọ nduzi n'akụkụ ha (mgbe ejikọtara ya na valvụ valvụ). Ndị ọrụ nọchiri akụkụ dị n'ime nke valvụ injection HPCS na akụkụ nke ndị na-ebubata ya mezigharịrị, ma kwughachi nkeji 2. The Tennessee River Basin Authority nyefere akụkọ na NRC na Jenụwarị 2013 n'okpuru 10 CFR Nkebi 21 gbasara ntụpọ dị na valvụ ọnụ ụzọ diski abụọ Anchor Darling na sistemu ịgba ume ume ọkụ nke Browns Ferry Nuclear Power Plant. N'ọnwa na-esote, onye na-ebu valvụ nyefere akụkọ 10 CFR Nkebi 21 na NRC gbasara imewe nke valvụ ọnụ ụzọ diski abụọ Anchor Darling, nke nwere ike ime ka valvụ ahụ kewapụ na diski ahụ. N'April 2013, Otu Ndị nwe mmiri na-esi mmiri na-esi nri nyere ndị otu ya akụkọ na akụkụ 21 akụkọ yana usoro atụ aro maka nyochaa arụmọrụ nke valves emetụtara. Ndụmọdụ gụnyere nyocha nchoputa yana nyochaa ntụgharị nke azuokokoosisi. N'afọ 2015, ndị ọrụ mere nyocha nyocha akwadoro na valvụ injection HPCS 2E22-F004 na LaSalle, mana ọ nweghị nsogbu arụmọrụ ahụghị. Na Febụwarị 8, 2017, ndị ọrụ jiri ntụzịaka nleba anya ngbanwe ntụgharị iji kwado ma nwalee valve injection HPCS 2E22-F004. N'April 2016, ndị na-ahụ maka mmiri esi mmiri degharịa akụkọ ha dabere na ozi nke onye nwe ụlọ ọrụ ọkụ nyere. Ndị ọrụ gbasasịrị 26 Anchor Darling valvụ ọnụ ụzọ diski okpukpu abụọ nke nwere ike ịdị mfe ma chọpụta na 24 n'ime ha nwere nsogbu. N'April 2017, Exelon gwara NRC na HPCS injection valve 2E22-F004 adịghị arụ ọrụ n'ihi nkewa nke valvụ na diski. N'ime izu abụọ, otu ndị ọrụ nyocha pụrụ iche (SIT) nke NRC goro bịarutere LaSalle ka ha nyochaa ihe kpatara ọdịda valvụ ahụ wee nyochaa ịdị irè nke usoro mmezi ndị e mere. SIT tụlere ntule Exelon maka ụdị ọdịda nke valvụ injection HPCS Unit 2. SIT kwetara na akụkụ dị n'ime valvụ ahụ gbawara n'ihi oke ike. Akụkụ ahụ gbajiri agbaji na-eme ka njikọ dị n'etiti eriri valvụ na diski intervertebral na-eme ka ọ ghara ịdị na-edozi ya, ruo mgbe diski intervertebral mechara kewapụ na valvụ ahụ. Onye na-eweta ya mezigharịrị nhazi ime nke valvụ ahụ iji dozie nsogbu ahụ. Exelon gwara NRC na June 2, 2017 na ọ na-ezube imezi 16 ndị ọzọ metụtara nchekwa na nchekwa dị mkpa Anchor Darling oghere ọnụ ụzọ diski abụọ, nke nwere ike ịdị mfe na nke a n'oge nkwụsị mmanụ na-esote nke abụọ LaSalle nkeji. Mmetụta nke usoro ọdịda. SIT tụlere ihe Exelon mere maka ichere ịrụzi valves iri na isii ndị a. SIT kwenyere na ihe kpatara ya bụ ihe ezi uche dị na ya, na otu ewepu - HCPS injection valve na Unit 1. Exelon mere atụmatụ ọnụ ọgụgụ nke cycles nke HPCS injection valves maka Unit 1 na Unit 2. Nkeji 2 valve bụ ngwa mbụ arụnyere na mmalite 1980s. , ebe valvụ Unit 1 gbanwere na 1987 mgbe e mebiri ya n'ihi ihe ndị ọzọ. Exelon rụrụ ụka na ọnụ ọgụgụ ka ukwuu nke ọrịa strok nke valvụ nke Unit 2 kọwara ọdịda ya, na e nwere ihe mere ị ga-eji chere ruo mgbe nkwụsị mmanụ ọkụ na-esote iji dozie nsogbu valvụ nke Unit 1. SIT zoro aka na ihe ndị dị ka ihe mgbagwoju anya nyocha tupu arụ ọrụ n'etiti. nkeji, obere iche iche imewe na nsonaazụ amaghi ama, njirimara ike ihe na-ejighị n'aka, yana ọdịiche na-ejighị n'aka na valvụ stem ka wedge thread wear, wee kwubie na "nke a bụ nsogbu oge" kama "Ọ bụrụ" 1E22-F004 valvụ ahụ ga-ada. Ọ bụrụ na enweghị ọdịda n'ọdịnihu, SIT azụtaghị nyocha oge nke valvụ 1 Exelon mechiri LaSalle Unit na June 22, 2017 iji dochie akụkụ dị n'ime nke valvụ injection HPCS 1E22-F004 chọpụtara na ụkpụrụ torque nke Exelon mepụtara maka moto nke HPCS injection valves 1E22-F004 na 2E22-F004 mebiri 10 CFR Nkebi 50, Ihe Mgbakwunye B, Standard III, Njikwa Nhazi na-eguzobe uru moto torque nke na-adịghị enwe nrụgide dị ukwuu na valvụ ahụ. Mana njikọ na-adịghị ike tụgharịrị bụrụ akụkụ ọzọ dị n'ime. Uru nke moto nke Exelon na-etinye na ya na-etinye akụkụ ahụ n'okpuru oke nrụgide, na-eme ka ọ gbajie na diski ikewapụ na valvụ ahụ. NRC kpebiri mmebi ahụ dị ka mmebi nke ọkwa III siri ike dabere na ọdịda valvụ nke gbochiri usoro HPCS ịrụ ọrụ nchekwa ya (na usoro ọkwa anọ, ọkwa m bụ nke kachasị njọ). Agbanyeghị, NRC gosipụtara ikike mmanye iwu ya dabere na amụma mmanye iwu ma ebipụtaghị mmebi iwu. NRC kpebisiri ike na ntụpọ imewe valvụ ahụ dị aghụghọ nke ukwuu maka Exelon iji buru ụzọ hụ ma dozie tupu ọdịda valvụ nke Unit 2. Exelon mara mma nke ukwuu na mmemme a. Ihe ndekọ SIT nke NRC na-egosi na Exelon maara akụkọ nke akụkụ 21 nke Tennessee River Basin Authority na ndị na-eweta valvụ mere na 2013. Ha enweghị ike iji mmata a chọpụta na dozie nsogbu valvụ injection 2 HPCS. Nke a abụghị n'ezie ngosipụta nke arụmọrụ ha adịghị mma. E kwuwerị, ha mebere usoro ndị otu onye nwe mmiri na-esi mmiri na-atụ aro maka akụkọ akụkụ abụọ nke 21. Ọdịmma dị na ntuziaka ahụ, ọ bụghị itinye ya n'ọrụ Exelon. Naanị ntụpọ dị na njikwa Exelon maka okwu a bụ na ihe kpatara ịgba ọsọ Unit 1 adịghị ike tupu ịlele ma valvụ injection HPCS ya mebiri emebi ma ọ bụ mebie, ruo mgbe a kwụsịrị ịgbanye mmanụ na-esote ya. Agbanyeghị, NRC's SIT nyeere Exelon aka ikpebi ịgbatị atụmatụ a ngwa ngwa. N'ihi ya, e mechiri nkeji 1 na June 2017 iji dochie valvụ Unit 1 na-adịghị ike. NRC dị ezigbo mma na mmemme a. Ọ bụghị naanị na NRC dugara Exelon na ebe nchekwa maka LaSalle Unit 1, mana NRC gwakwara ụlọ ọrụ niile ka ha dozie okwu a n'egbughị oge na-enweghị isi. NRC nyere ndị nwe ụlọ mmepụta ihe ozi 2017-03 ozi na June 15, 2017, gbasara ntụpọ imewe nke valvụ ọnụ ụzọ diski abụọ Anchor Darling na njedebe nke ntuziaka nlekota oru valve. NRC nwere usoro nzukọ ọha na eze na ndị ụlọ ọrụ na ndị na-eweta valve na nsogbu na ngwọta ya. Otu n'ime ihe si na mmekọrịta ndị a pụta bụ na ụlọ ọrụ ahụ edepụtala usoro usoro, atụmatụ nhazi nke nwere njedebe njedebe na-erughị December 31, 2017, na nyocha maka iji Anchor Darling valves ọnụ ụzọ diski okpukpu abụọ na ike nuklia US. osisi. Nnyocha na-egosi na ihe dị ka 700 Anchor Darling double disc valves (AD DDGV) na-eji ike nuklia na United States, ma ọ bụ naanị 9 valves nwere àgwà nke nnukwu ihe ize ndụ dị elu / ọkara, valves multi-stroke. (Ọtụtụ valvụ bụ otu-stroke, n'ihi na ọrụ nchekwa ha bụ imechi mgbe emepere ya, ma ọ bụ meghee mgbe emechiri. ụlọ ọrụ ka nwere oge iji nwetaghachi ọdịda ya site na mmeri, mana NRC dị njikere ịhụ n'oge na nsonaazụ dị irè site na nke a. Ziga SMS "SCIENCE" na 662266 ma ọ bụ debanye aha na ntanetị. Debanye aha ma ọ bụ zipu SMS "SCIENCE" na 662266. Enwere ike ị nweta ụgwọ SMS na ụgwọ data. Ederede a kwụsịrị ịpụ. Ọ dịghị mkpa ịzụta. 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