Kukuvadzwa kwevhavha mune emergency system yeLaSalle nuclear power plant

Chitubu ichi, NRC Special Inspection Team (SIT) yakaita ongororo yeLaSalle Nuclear Power Plant kuti iongorore chikonzero chekukundikana kwevhavha uye kuongorora kushanda kwekugadzirisa matanho akatorwa. Iwo maviri mayuniti eExelon Generation Company's LaSalle County Nuclear Power Plant, anenge mamaira gumi neshanu maodzanyemba kwakadziva kumabvazuva kweOttawa, Illinois, ari kufashaidza mareactor emvura (BWR) akatanga kushanda mukutanga kwema1980. Kunyangwe maBWR mazhinji anoshanda muUnited States ari BWR/4 aine Mark I mudziyo dhizaini, "zvitsva" LaSalle zvishandiso zvinoshandisa iyo BWR/5 ine Mark II mudziyo dhizaini. Musiyano mukuru muongororo iyi ndewekuti kunyangwe iyo BWR/4 inoshandisa steam-driven high-pressure coolant injection (HPCI) system kuti ipe mvura inotonhorera yekuwedzera kune reactor core kana pombi diki yakabatana neiyo reactor ngarava ikatsemuka, kushandiswa kwe BWR/5 A motor-driven high-pressure core spray (HPCS) system inoita basa rekuchengetedza iri. Musi waFebruary 11, 2017, mushure mekugadzirisa hurongwa uye kuongororwa, vashandi vakaedza kuzadzazve No. 2 high-pressure core spray (HPCS) system. Panguva iyoyo, reactor yeUnit 2 yakavharwa nekuda kwekuvhiringidzwa kwekuwedzera, uye nguva yekudzikisa yakashandiswa kutarisa zvirongwa zvekukurumidzira, zvakadai seHPCS system. Iyo HPCS sisitimu kazhinji iri mumodhi yekumira panguva yekuvhiya reactor. Iyo sisitimu yakashongedzerwa nepombi inotyairwa nemota iyo inogona kupa yakagadziridzwa yekuwedzera kuyerera kwe7,000 magaloni paminiti kune reactor ngarava. Iyo pombi yeHPCS inodhonza mvura kubva mutangi remukati mumudziyo. Kana pombi diki-dhiyamita yakabatana nemudziyo we reactor ikatsemuka, mvura inotonhorera inodonha, asi kumanikidza mukati memudziyo we reactor kunoitwa nenhevedzano yepasi-pressure masisitimu echimbichimbi (kureva. ) Mvura inoyerera ichibva pakaputsika pombi inobuditswa kutangi rekudzvanya kuti ishandiswezve. Iyo pombi inotyairwa yeHPCS pombi inogona kuvezwa kubva kune-off-saiti grid kana iripo, kana kubva pane-saiti emergency dhiziri jenareta kana grid isipo. Vashandi havana kukwanisa kuzadza pombi pakati peiyo HPCS jekiseni valve (1E22-F004) uye reactor mudziyo. Vakaona kuti dhisiki yakaparadzaniswa kubva padzinde rembiri-clapper gedhi valve yakagadzirwa naAnchor Darling, ichivharira nzira yekuyerera yepombi yekuzadza. Iyo HPCS jekiseni vharafu ivharuvhu yemagetsi inowanzovharika inovhura kana iyo HPCS system yatangwa kupa chiteshi chekugadzira-mvura yemvura kuti isvike kune reactor ngarava. Iyo mota inoshandisa torque kutenderedza spiral valve stem kusimudza (kuvhurika) kana kudzikisa (kuvhara) disc muvharuvhu. Kana yakadzikiswa zvizere, dhisiki inovhara kuyerera kuburikidza nevhavha. Kana chivharo chevharuvhu chasimudzwa zvizere, mvura inoyerera nepakati pevharuvhu inoyerera isina kuvharika. Sezvo dhisiki yakaparadzana kubva pachigadziko chevhavha munzvimbo yakaderedzwa zvakakwana, motokari inogona kutenderera tsinde yevhavha sekuti inosimudza diski, asi disc haigoni kufamba. Vashandi vakatora mifananidzo yeakaparadzaniswa maviri discs mushure mekubvisa chivharo chevhavha (sleeve) yevhavha (Mufananidzo 3). Mupendero wepasi pehunde unoonekwa pakati pepamusoro pemufananidzo. Iwe unogona kuona madhisiki maviri uye njanji inotungamira padivi pavo (kana yakabatana nevhavha hunde). Vashandi vakatsiva zvikamu zvemukati zveHPCS injection valve nezvikamu zvakagadziriswa nemutengesi, uye vakadzokorora nhamba ye2. Tennessee River Basin Authority yakaendesa mushumo kuNRC muna Ndira 2013 pasi pe10 CFR Chikamu 21 maererano nezvakakanganiswa muAnchor Darling double disc gedhi vharafu mu-high-pressure coolant injection system yeBrown Ferry Nuclear Power Plant. Mwedzi wakatevera, mupi wevhavha akatumira 10 CFR Chikamu 21 mushumo kuNRC pamusoro pekugadzirwa kweAnchor Darling double disc gedhi valve, iyo inogona kuita kuti chivharo chevhavha chiparadzanise kubva kune disc. Muna Kubvumbi 2013, Boiling Water Reactor Owners Group yakapa mushumo weChikamu 21 kunhengo dzayo uye nzira dzakakurudzirwa dzekutarisa kushanda kwemavharuvhu akakanganisika. Zvinokurudzirwa zvinosanganisira kuongororwa kwekuongorora uye kutarisa kutenderera kwehunde. Muna 2015, vashandi vakaita yakakurudzirwa kuongororwa bvunzo paHPCS jekiseni valve 2E22-F004 muLaSalle, asi hapana matambudziko ekuita akawanikwa. Musi waFebruary 8, 2017, vashandi vakashandisa stem rotation monitoring guide kuchengetedza uye kuedza HPCS jekiseni valve 2E22-F004. Muna Kubvumbi 2016, boka revaridzi vemvura inovira reactor rakagadziridza mushumo wavo zvichienderana neruzivo rwakapihwa nemuridzi wemagetsi emagetsi. Vashandi vakaparadzanisa 26 Anchor Darling double disc gedhi mavharuvhu angave ari panjodzi uye vakaona kuti makumi maviri nemana avo aive nematambudziko. MunaEpril 2017, Exelon yakazivisa NRC kuti HPCS jekiseni valve 2E22-F004 yakanga isina kushanda nekuda kwekuparadzaniswa kwegumbo revhavha uye disc. Mumavhiki maviri, boka rekuongorora rakakosha (SIT) rakabhadharwa neNRC rakasvika muLaSalle kuti riongorore chikonzero chekukundikana kwevhavha uye kuongorora kushanda kwemaitiro ekugadzirisa akatorwa. SIT yakaongorora kuongororwa kwaExelon kwekukundikana kweiyo Unit 2 HPCS jekiseni valve. SIT yakabvumirana kuti chimwe chikamu mukati mevharuvhu chakaputika nekuda kwesimba rakawandisa. Chikamu chakaputsika chinokonzera kuwirirana pakati pevhavha yevhavha uye intervertebral disc kuti iite zvishoma uye zvishoma, kusvikira intervertebral disc pakupedzisira yakaparadzana kubva pavhavha yevhavha. Mutengesi akagadzirisa zvakare chimiro chemukati chevhavha kuti agadzirise dambudziko. Exelon yakazivisa NRC musi waChikumi 2, 2017 kuti inoronga kugadzirisa 16 zvimwe zvine chekuita nekuchengetedza uye zvakakosha-zvakakosha Anchor Darling kaviri-disc gedhi mavharuvhu, ayo anogona kuve ari panjodzi kune izvi panguva inotevera yekukanganisa kwekuwedzera kwezvikamu zviviri zveLaSalle. Kukanganisa kwemaitiro ekukundikana. SIT yakaongorora zvikonzero zveExelon zvekumirira kugadzirisa aya gumi nematanhatu mavharuvhu. SIT anotenda kuti chikonzero chacho chinonzwisisika, kunze kwechimwe chete-iyo HCPS jekiseni valve paChipatimendi 1. Exelon inofungidzira nhamba yezvikamu zveHPCS majekiseni mavharuvhu eChikwata 1 uye Unit 2. The Unit 2 valve ndiyo yekutanga midziyo yakaiswa mukutanga kwema1980. , nepo Unit 1 valve yakatsiviwa muna 1987 mushure mokunge yakuvadzwa nokuda kwezvimwe zvikonzero. Exelon akatsigira kuti nhamba huru yekurova kwevhavha yeUnit 2 yakatsanangura kukundikana kwayo, uye pakanga pane chikonzero chekumirira kusvikira kukanganiswa kwekuwedzera kwekuwedzera kugadzirisa dambudziko revhavha yeUnit 1. SIT yakataura zvinhu zvakadai sezvisingazivikanwi pre-operation test kusiyana pakati. mayuniti, misiyano midiki yekugadzira ine mhedzisiro isingazivikanwe, kusava nechokwadi kwesimba rezvinhu, uye kusavimbika mutsauko wevharuvhu hunde kusvika kune wedge shinda kupfeka, uye akagumisa kuti "ichi ndicho "dambudziko reNguva" pachinzvimbo che "Kana" 1E22-F004 Ivhavha ichakundikana. kana pasina kukundikana mune ramangwana Nemamwe mashoko, SIT haina kutenga kunonoka kuongorora kweChikwata 1 valve yakavhara LaSalle Unit 1 paJune 22, 2017 kuti itsive zvikamu zvemukati zve HPCS 1E22-F004 SIT akawana kuti torque yakagadziridzwa neExelon yemamotor eHPCS jekiseni mavharuvhu 1E22-F004 uye 2E22-F004 akatyora 10 CFR Chikamu 50, Appendix B, Standard III, Dhizaini Kudzora inogadza kukosha kwemota torque iyo isingaite yakawandisa kudzvanywa pahunde yevharuvhu. Asi chinongedzo chisina kusimba chakazove chimwe chikamu chemukati. Iyo mota torque kukosha yakashandiswa naExelon yakaisa chikamu ichi pasi pekunetseka kwakanyanya, zvichiita kuti iparare uye dhisiki riparadzane kubva pachitsiko chevharuvhu. Iyo NRC yakasarudza kutyora seyakanyanya nhanho III kutyorwa kunoenderana nekutadza kwevharuvhu kwakadzivirira iyo HPCS system kuita mabasa ayo ekuchengetedza (mune-level system, level I ndiyo yakanyanya kuomarara). Nekudaro, iyo NRC yakashandisa kungwara kwayo kwekuteedzera mutemo zvinoenderana nemutemo wayo wekuteedzera mutemo uye haina kuburitsa kutyora. Iyo NRC yakasarudza kuti chikanganiso chekugadzira vharafu chaive chakanyanya kujeka kuti Exelon aone uye agadzirise pamberi pekutadza kweiyo Unit 2 valve. Exelon aitaridzika zvakanaka pachiitiko ichi. Zvinyorwa zveSIT zveNRC zvinoratidza kuti Exelon inoziva nezveChikamu 21 mushumo wakaitwa neTennessee River Basin Authority uye nemutengesi wevharuvhu muna 2013. Havana kukwanisa kushandisa ruzivo urwu kuziva nekugadzirisa Unit 2 HPCS matambudziko evharuvhu. Izvi hazvisi kuratidza kusaita kwavo zvakanaka. Mushure mezvose, vakaita matanho akakurudzirwa neBoiling Water Reactor Owner's Boka kune maviri Chikamu 21 mishumo. Kukanganisa kuri mugwara, kwete mashandisirwo akaitwa naExelon. Chikanganiso chete mukubata kwaExelon kwenyaya iyi ndechekuti chikonzero chekumhanyisa Unit 1 chaive chisina kusimba isati yatarisa kana HPCS jekiseni vharuvhu yakakuvadzwa kana kukuvadzwa, kudzamara kurongedzerwa kwayo kwakazokanganiswa. Nekudaro, NRC's SIT yakabatsira Exelon kusarudza kukurumidzira chirongwa. Nekuda kweizvozvo, Unit 1 yakavharwa muna Chikumi 2017 kutsiva iyo isina njodzi Unit 1 valve. NRC yaitaridzika zvakanaka pachiitiko ichi. Kwete chete iyo NRC yakatungamira Exelon kunzvimbo yakachengeteka yeLaSalle Unit 1, asi NRC yakakurudzirawo indasitiri yese kugadzirisa nyaya iyi pasina kunonoka kusingaite. NRC yakapa chiziviso che2017-03 kuvaridzi vefekitori musi waChikumi 15, 2017, maererano nekukanganisa kwedhizaini yeAnchor Darling kaviri disc gedhi vharafu uye kugumira kweiyo valve performance monitoring nhungamiro. NRC yakaita nhevedzano yemisangano yeruzhinji neindasitiri uye vamiriri vevashambadzi vevharuvhu padambudziko nemhinduro dzaro. Imwe yemhedzisiro yekudyidzana uku ndeyekuti indasitiri yakanyora akateedzana nhanho, chirongwa chekugadzirisa chine chinangwa chekupedzisira pasati papfuura Zvita 31, 2017, uye kuferefetwa kwekushandiswa kweAnchor Darling kaviri disc gedhi mavharuvhu muUS simba renyukireya. zvinomera. Ongororo inoratidza kuti angangoita 700 Anchor Darling double disc gedhi mavharuvhu (AD DDGV) anoshandiswa mumagetsi emagetsi enyukireya muUnited States, asi mavharuvhu 9 chete ndiwo ane hunhu hwepamusoro / hwepakati njodzi, mavharuvhu akawanda ane sitiroko. (Mavhavha akawanda ane-single-stroke, nokuti basa ravo rekuchengetedza nderokuvhara kana rakavhurwa, kana kuzarura kana rakavharwa. Mavharuvhu akawanda anogona kunzi akavhurika uye akavharika, uye anogona kuvhurwa uye kuvharwa kakawanda kuti aite basa rawo rekuchengetedza.) indasitiri ichine nguva yekuwanazve kutadza kwayo kubva mukukunda, asi iyo NRC inoratidzika kunge yakagadzirira kuona yakakodzera uye inoshanda mhedzisiro kubva pane iyi nyaya. Tumira SMS "SCIENCE" ku662266 kana kunyoresa pamhepo. Bhalisa kana kutumira SMS "SAYENSI" ku662266. Mari yeSMS uye data inogona kubhadharwa. Mavara anomira kubuda. Hapana chikonzero chekutenga. Mitemo nemamiriro. © Union of Concerned Scientists Isu tiri 501 (c) (3) sangano risina purofiti. 2 Brattle Square, Cambridge MA 02138, USA (617) 547-5552