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 sistemu ikuku ume ume ọkụ (HPCI) na-ebugharị iji nye mmiri jụrụ oyi na isi ihe mgbe obere ọkpọkọ na-ejikọ ụgbọ mmiri reactor gbawara, BWR/5. na-eji usoro High Pressure Core Spray (HPCS) na-ebugharị moto iji nweta ọrụ nchekwa a.
Na February 11, 2017, mgbe nhazi usoro na ule nyocha, ndị ọrụ gbalịrị mejupụta usoro nke 2 high-pressure core injection (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 megharịrị, 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 nsogbu 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 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 dara n'ihi nkewa nke valvụ na diski. N'ime izu abụọ, otu ndị ọrụ nyocha pụrụ iche (SIT) nke NRC nyere ikike bịarutere LaSalle ka ha nyochaa ihe kpatara ọdịda valvụ ahụ ma 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-emewanyewanye nke ọma, 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 valvụ ọnụ ụzọ diski abụọ nwere ike ịdị mfe na ọdịda a n'oge nkwụsị mmanụ na-esote nke ngalaba LaSalle abụọ mmetụta mmetụta nke usoro.
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, ma ewezuga - valve injection HCPS na Unit 1. Exelon mere atụmatụ ọnụọgụ nke okirikiri nke valvụ injection HPCS maka nkeji 1 na nkeji 2. valvụ nke 2 bụ ngwa mbụ arụnyere na mmalite. 1980s, mgbe Unit 1 valvụ dochie ya na 1987 mgbe e mebiri ya n'ihi ihe ndị ọzọ. Exelon rụrụ ụka na ọnụ ọgụgụ ka ukwuu nke strok valvụ maka unit 2 kọwara ọdịda ya na enwere ihe mere ị ga-eji chere ruo mgbe nkwụsị mmanụ na-esote iji dozie nsogbu valve maka unit 1.
SIT kwuru ihe ndị dị ka ọdịiche nnwale tupu arụ ọrụ nke amabeghị n'etiti nkeji, obere iche iche imewe nwere nsonaazụ amaghi ama, njirimara ike ihe ejighi n'aka, na esemokwu ejighị n'aka na valvụ stem ka wedge thread wear, wee kwubie na “nke a bụ “nsogbu oge” kama "Ọ bụrụ" 1E22-F004 valvụ ga-ada ma ọ bụrụ na ọ dịghị ọdịda n'ọdịnihu. N'ikwu ya n'ụzọ ọzọ, SIT azụtaghị nyocha oge nke valvụ Unit 1.
Exelon mechiri nkeji 1 LaSalle na June 22, 2017 iji dochie akụkụ dị n'ime nke valvụ injection HPCS 1E22-F004.
SIT chọpụtara na ụkpụrụ torque nke Exelon mepụtara maka moto nke HPCS injection valves 1E22-F004 na 2E22-F004 mebiri 10 CFR Nkebi 50, Mgbakwunye B, Standard III, njikwa njikwa. Exelon na-eche na valvụ valvụ bụ njikọ na-adịghị ike, ma guzobe uru nke moto nke na-adịghị edozi valvụ ahụ na nrụgide dị ukwuu. Mana njikọ na-adịghị ike tụgharịrị bụrụ akụkụ ọzọ dị n'ime. Ọnụ ego nke moto nke Exelon na-etinye na-etinye akụkụ ahụ n'okpuru nrụgide dị ukwuu, 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 hụ nke ọma ma dezie 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 Ụlọ Ọrụ Ndagwurugwu Tennessee na ndị na-eweta valve na 2013. Ha enweghị ike iji mmata a chọpụta ma dozie nsogbu valvụ injection 2 HPCS dị ka ngosipụta nke arụmọrụ ha na-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, a na-emechi 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, ma ọ bụ meghee mgbe emechiri.
Ụlọ ọrụ ahụ ka nwere oge iji nwetaghachi ọdịda ya site na mmeri, ma NRC yiri ka ọ dị njikere ịhụ n'oge na nsonaazụ dị irè site na nke a.
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Oge nzipu: Jun-23-2021
