Nuburyo bwo kwangirika kwangirika kwimiyoboro idafite ibyuma, imiyoboro yicyuma yashyizwe mubidukikije byo mu nyanja irashobora kwangirika muburyo butandukanye mubuzima bwabo buteganijwe.Iyi ruswa irashobora gukurura imyuka ihumanya ikirere, igihombo cyibicuruzwa nibishobora guteza ingaruka.Abashoramari ba Offshore hamwe nababikora barashobora kugabanya ibyago byo kwangirika mugaragaza ibikoresho bikomeye byumuyoboro kuva mugitangira kugirango barwanye ruswa.Nyuma yibyo, bagomba gukomeza kuba maso mugihe basuzumye imirongo yatewe inshinge, imirongo ya hydraulic na impulse, hamwe nibikoresho hamwe nibikoresho kugirango barebe ko ruswa idahungabanya ubusugire bwimiyoboro yashizweho cyangwa guhungabanya umutekano.
Ruswa yaho irashobora kuboneka kumahuriro menshi, amato, amato hamwe nu miyoboro yo hanze.Iyi ruswa irashobora kuba muburyo bwo gutobora cyangwa kwangirika, kimwe muricyo gishobora kwangiza urukuta rw'imiyoboro kandi bigatuma amazi arekurwa.
Ibyago byo kwangirika byiyongera uko ubushyuhe bwimikorere ya porogaramu bwiyongera.Ubushuhe burashobora kwihutisha iyangirika rya firime irinda passiyo ya oxyde yo hanze, bityo igateza imbere.
Kubwamahirwe, gutobora ahantu hamwe no kwangirika biragoye kubimenya, bigatuma bigorana kumenya, guhanura, no gushushanya ubu bwoko bwa ruswa.Bitewe nizi ngaruka, ba nyiri platform, abakora nabashinzwe kugena bagomba kwitonda muguhitamo ibikoresho byiza byumuyoboro kugirango babisabe.Guhitamo ibikoresho numurongo wabo wambere wo kwirinda ruswa, kubwibyo rero ni ngombwa cyane.Kubwamahirwe, barashobora gukoresha igipimo cyoroshye cyane ariko cyiza cyane cyo kurwanya ruswa yaho, Piting Resistance ihwanye numubare (PREN).Iyo hejuru ya PREN agaciro k'icyuma, niko irwanya kurwanya ruswa.
Iyi ngingo irareba uburyo bwo kumenya ibibyimba byangirika hamwe nuburyo bwo guhitamo uburyo bwo gutoranya ibikoresho bya peteroli na gazi yo mu mahanga hashingiwe ku gaciro ka PREN.
Kwangirika kwiherereye biboneka ahantu hato ugereranije no kwangirika muri rusange, bikaba bisa neza hejuru yicyuma.Gutobora no gutobora bitangira kuboneka kuri 316 ibyuma bitagira umuyonga mugihe firime yo hanze ya chromium ikungahaye kuri pasiporo ya oxyde yicyuma yatanyaguwe no guhura namazi yangirika, harimo namazi yumunyu.Ibidukikije byo mu nyanja bikungahaye kuri chloride, kimwe nubushyuhe bwo hejuru ndetse no kwanduza hejuru yigituba, byongera amahirwe yo kwangirika kwiyi firime.
Gutobora Kwangirika bibaho iyo firime ya passivation ku gice cyumuyoboro isenyutse, ikora imyenge mito cyangwa ibyobo hejuru yumuyoboro.Ibyobo nk'ibyo birashoboka gukura uko amashanyarazi agenda akomeza, bitewe nuko icyuma kiri mu cyuma gishonga mugisubizo munsi yumwobo.Icyuma gishongeshejwe noneho kizakwirakwira hejuru yurwobo hanyuma gihindurwe kugirango kibe oxyde cyangwa ingese.Mugihe urwobo rwimbitse, reaction ya electrochemic reaction irihuta, ruswa ikiyongera, ibyo bikaba byaviramo gutobora urukuta rw'imiyoboro kandi biganisha kumeneka.
Imiyoboro irashobora kwibasirwa cyane niba isura yinyuma yanduye (Ishusho 1).Kurugero, ibyanduye biva mubikorwa byo gusudira no gusya birashobora kwangiza passivation oxyde ya pisine, bityo bigakora kandi byihuta.Ni nako bigenda mu guhangana gusa n’umwanda uva mu miyoboro.Byongeye kandi, uko ibitonyanga byumunyu bigenda bishira, kristu yumunyu itose ikora kumiyoboro irinda igice cya oxyde kandi ishobora gutera umwobo.Kugira ngo wirinde ubwo bwoko bwanduye, komeza imiyoboro yawe uyisukure buri gihe n'amazi meza.
Igicapo 1. 316 / 316L umuyoboro wibyuma udahumanye wanduye aside, saline, nibindi bibitswemo birashobora kwibasirwa cyane.
ruswa.Mubihe byinshi, gutobora birashobora gutahurwa byoroshye nuwabikoresheje.Nyamara, kwangirika kwa crevice ntabwo byoroshye kubimenya kandi biteza ibyago byinshi kubakoresha n'abakozi.Ubusanzwe bibaho kumiyoboro ifite itandukaniro rito hagati yibikoresho bikikije, nk'imiyoboro ifashwe ahantu hamwe na clamp cyangwa imiyoboro ipakiye neza kuruhande.Iyo ubwonko bwinjiye mu cyuho, uko igihe kigenda gihita, hashyizweho umuti wa ferric chloride ferricique (FeCl3) ukomoka kuri chimique (FeCl3), utera kwangirika kwicyuho (Ishusho 2).Kubera ko ruswa yangirika bitewe na kamere yayo byongera ibyago byo kwangirika, ruswa ishobora kwangirika ku bushyuhe buke cyane kuruta gutobora.
Igishushanyo 2 - Kwangirika kwa Crevice birashobora gutera imbere hagati yumuyoboro nuyoboro (hejuru) nigihe iyo umuyoboro ushyizwe hafi yandi masura (hepfo) bitewe no gushiraho imiti ikaze ya chimide ya chloride ferric mu cyuho.
Kwangirika kwa crevice mubisanzwe bigereranya gushira mbere mu cyuho cyakozwe hagati yigice cyumuyoboro na cola yunganira.Ariko, kubera ubwiyongere bwa concentration ya Fe ++ mumazi imbere yamenetse, umuyoboro wambere uba munini kandi munini kugeza utwikiriye ibice byose.Ubwanyuma, ruswa ishobora kwangirika gutobora umuyoboro.
Ibice byinshi byerekana ibyago byinshi byo kwangirika.Kubwibyo, clamp clamp izengurutse igice kinini cyumuzenguruko usanga ishobora guteza ibyago kuruta clamp zifunguye, bigabanya ubuso bwo guhuza imiyoboro na clamp.Abatekinisiye ba serivise barashobora gufasha kugabanya amahirwe yo kwangirika kwangirika cyangwa kunanirwa mugukingura buri gihe ibikoresho no kugenzura imiyoboro ya ruswa.
Gutobora no gutobora birashobora gukumirwa muguhitamo icyuma gikwiye kugirango kibe cyihariye.Abasobanuzi bagomba gukoresha umwete muguhitamo ibikoresho byiza byo kuvoma kugirango bagabanye ingaruka zo kwangirika, bitewe nibikorwa bikora, imiterere yimikorere, nibindi bihinduka.
Gufasha abadondora guhitamo ibikoresho byabo, barashobora kugereranya PREN indangagaciro zibyuma kugirango bamenye ko barwanya ruswa.PREN irashobora kubarwa uhereye kuri chimie ya alloy, harimo chromium (Cr), molybdenum (Mo), hamwe na azote (N), nkibi bikurikira:
PREN yiyongera hamwe nibirimo ibintu birwanya ruswa ya chromium, molybdenum na azote muri alloy.Ikigereranyo cya PREN gishingiye ku bushyuhe bukomeye bwo gutobora (CPT) - ubushyuhe bwo hasi cyane aho ibyobo bibera - ku byuma bitandukanye bitagira umwanda bitewe n’ibigize imiti.Byibanze, PREN ihwanye na CPT.Kubwibyo, indangagaciro za PREN zerekana hejuru yo guhangana.Ubwiyongere buke muri PREN buhwanye no kwiyongera gake muri CPT ugereranije na alloy, mugihe kwiyongera kwinshi muri PREN byerekana iterambere ryinshi mubikorwa hejuru ya CPT yo hejuru cyane.
Imbonerahamwe 1 igereranya indangagaciro za PREN kubintu bitandukanye bikunze gukoreshwa mu nganda za peteroli na gaze hanze.Irerekana uburyo ibisobanuro bishobora kunoza cyane kurwanya ruswa muguhitamo imiyoboro ihanitse.PREN yiyongera gato kuva 316 SS ikagera kuri 317 SS.Super Austenitike 6 Mo SS cyangwa Super Duplex 2507 SS nibyiza kubikorwa byunguka.
Nikel nyinshi (Ni) yibanze cyane mubyuma bidafite ingese nabyo byongera ruswa.Nyamara, nikel irimo ibyuma bitagira umwanda ntabwo biri muburinganire bwa PREN.Ibyo ari byo byose, akenshi ni byiza guhitamo ibyuma bidafite ingese hamwe na nikel yo hejuru, kuko iki kintu gifasha gusubirana hejuru yerekana ibimenyetso byerekana ruswa.Nickel ituza austenite kandi ikarinda martensite mugihe yunamye cyangwa gushushanya ubukonje 1/8 umuyoboro ukomeye.Martensite nicyiciro cya kirisiti itifuzwa mubyuma bigabanya ubukana bwibyuma bitangirika kwangirika kwangirika hamwe na chloride iterwa no guhagarika umutima.Nikel irenze byibuze 12% muri 316 / 316L ibyuma nabyo birakenewe kubisabwa ingufu za gaze ya hydrogen.Nibura byibuze nikel isabwa kuri ASTM 316 / 316L ibyuma bidafite ingese ni 10%.
Ruswa yaho irashobora kugaragara ahantu hose mumiyoboro ikoreshwa mubidukikije.Nubwo bimeze bityo ariko, gutobora birashoboka cyane mubice bimaze kwanduzwa, mugihe ruswa ishobora kwangirika ahantu hafite icyuho gito hagati yimiyoboro nibikoresho byo kuyishyiraho.Ukoresheje PREN nkibanze, uwatanze ibisobanuro arashobora guhitamo icyiciro cyiza kugirango agabanye ingaruka zubwoko ubwo aribwo bwose.
Ariko, uzirikane ko hari izindi mpinduka zishobora kugira ingaruka zo kwangirika.Kurugero, ubushyuhe bugira ingaruka kumurwanya wibyuma bidafite ingese.Ibihe bishyushye byo mu nyanja, ibyuma bya super austenitis 6 molybdenum cyangwa super duplex 2507 imiyoboro idafite ibyuma bigomba kwitabwaho cyane kuko ibyo bikoresho bifite imbaraga zo kurwanya ruswa ndetse no guturika kwa chloride.Kubihe bikonje, umuyoboro wa 316 / 316L urashobora kuba uhagije, cyane cyane niba hari amateka yo gukoresha neza.
Abashoramari ba Offshore hamwe nababikora barashobora kandi gufata ingamba zo kugabanya ibyago byo kwangirika nyuma yo gushyirwaho igituba.Bagomba guhora bafite isuku kandi bagahora baterwa namazi meza kugirango bagabanye ibyago byo gutoboka.Bagomba kandi kuba abatekinisiye babungabunga bafungura clamp mugihe cyo kugenzura bisanzwe kugirango barebe ko ruswa yangirika.
Mugukurikiza intambwe zavuzwe haruguru, ba nyir'ibikorwa n'ababikora barashobora kugabanya ibyago byo kwangirika kw'imiyoboro hamwe no gutemba bifitanye isano n'ibidukikije byo mu nyanja, kuzamura umutekano no gukora neza, no kugabanya amahirwe yo gutakaza ibicuruzwa cyangwa ibyuka bihumanya.
Brad Bollinger is the Oil and Gas Marketing Manager for Swagelok. He can be contacted at bradley.bollinger@swagelok.com.
Ikinyamakuru cy’ikoranabuhanga rya peteroli, ikinyamakuru cyamamaye cy’umuryango w’abashoramari ba peteroli, gitanga ibisobanuro byemewe n’ingingo zerekana iterambere mu ikoranabuhanga rigezweho, ibibazo bya peteroli na gaze, namakuru yerekeye SPE n’abanyamuryango bayo.