Ngā Tikanga Whakarewa Nikara mō te Ahumahi Matūriki
Ka whakahaerehia te umanga matū hinu i raro i ngā āhuatanga uaua: te pāmahana teitei, te pēhanga teitei, me te pānga ki ngā mea waikura pērā i te pūhaumāota, te whanariki, te H₂S, te CO₂, me ngā momo matū waikawa. I roto i ēnei taiao, ko te whiriwhiri rauemi te mea nui hei whakatau i te pono o ngā taputapu tukatuka. He whānuitia te whakamahinga o ngā konganuku nikara (te nikara me ōna koranu) nā te mea he ātete pai ki te waikura, he pumau ki te pāmahana teitei, me te kaha ki te ātete ki te pakaru waikura ahotea. Heoi, ka taea anake te whakatutuki i ēnei painga mēnā ka whakahaerehia te tukanga whakarewa mā te whakamahi i te tikanga tika, nā te mea ka taea e te whakarewa te whakarerekē i te hanganga moroiti o te rauemi, ka puta ai ngā pakaru wera, te porosity, ka whakaiti rānei i te ātete waikura i roto i te rohe whakarewa.
1. Te tūranga o ngā konukōre nikara i roto i ngā matū hinu
Ko ngā koranu nikara pērā i te Nikara 200/201, Monel (Ni-Cu), Inconel (Ni-Cr-Fe), Incoloy, me Hastelloy (Ni-Mo-Cr) e whakamahia whānuitia ana i roto i ngā whakawhiti wera, ngā pou whakatō, ngā tauhohenga, ngā paipa tukatuka, ngā taputapu tango whanariki, me ngā pūnaha e mahi ana ki ngā waikawa me ngā pūhaumāota. Hei tauira, he pai te ātete waikura o ngā koranu Ni-Cr i ngā pāmahana teitei, ko ngā koranu Ni-Mo ia he tino pai ki te whakaiti i ngā taiao me ētahi otinga waikawa. Ko te whakarewa i ēnei koranu me pupuri tonu te hanganga huānga o te koranu kia mau tonu te ātete waikura pai rawa atu.
2. Ngā wero motuhake i roto i te whakarewa nikara
I te nuinga o te wā, he iti ake te kawe wera o ngā koranu nikara i te maitai waro, ā, he nui ake te tauwehenga o te whakawhānui wera. Nā tēnei huinga ka nui ake te kukū wera i roto i te wāhi whakarewa, ā, ka piki ake pea te hē. Hei tāpiri, he tairongo ētahi koranu nikara ki:
– Te pakaru wera (te pakaru totoka) nā te wehenga o ngā huānga i ngā rohe o te kōpaka i te wā e totoka ana te konganuku whakarewa.
– Ko te poke, te makuku, te hau rānei e mau ana ka puta ai te porousness.
– Te whakaaweawe, te whakaiti rānei i te ātete ki te waikura ā-rohe mēnā kāore i te tika te tukanga whakarewa, inā koa i runga i ētahi koranu.
– Ka taea e te poke o te rino/waro mai i ngā taputapu mahi maitai te whakararu i te ātete ki te waikura, inā koa i roto i ngā taiao matū kaha.
Nō reira, ko te whakahaere i te horoi, te kōwhiringa whakakī, me ngā tawhā wera te mea matua.
3. Kōwhiringa tukanga whakarewa: GTAW, GMAW, SMAW, me SAW
Ko ētahi o ngā tukanga whakarewa noa mō ngā koranu nikara i roto i ngā matū hinu ko:
a) GTAW (TIG)
Ko te GTAW te tikanga pai rawa atu mō ngā putanga pakiaka paipa, te mahi tika, me te rauemi angiangi. Ko ōna painga ko te whakahaere wera pai me ngā whakarewa ma. He maha ngā wā ka whakamahia te whakamarumaru hau argon parakore; i ētahi whakamahinga, ka taea te tāpiri i te herium hei whakapai ake i te urunga.
b) GMAW (MIG) me te GMAW pāorooro
He pai te GMAW mō te tere ake o te whakaputa, inā koa i roto i te hanganga awheawhe. Ka āwhina te aratau pulsed ki te whakaiti i te wera e uru mai ana me te tauhiuhi, me te whakapai ake i te mana whakahaere i ngā tūranga whakarewa uaua. Me penapena me te whakahaere tika i te waea whakarewa kia kore ai e poke.
c) SMAW (whakarewa hiko)
He māmā noa iho ngā taputapu e whakamahia whānuitia ana te SMAW mō ngā whakatikatika i te mara. Heoi anō, me whakahaere ngā mōrearea o te kohi hauwai me te whakaurunga o te para mā te whiriwhiri tika i ngā hiko, ngā tikanga tunu hiko, mēnā e tika ana, me ngā tikanga horoi i waenga i ngā paparanga.
d) IA
He whai hua te SAW mō ngā pereti matotoru me ngā whakarewa roa, pērā i ngā oko pēhanga, i ngā anga rānei. Me tika te whiriwhiri i te rere me te waea kia mau tonu ai te ātete waikura e hiahiatia ana i roto i te hanganga whakarewa whakarewa.
4. Te whakarite rauemi me te horoi mata
He nui te pānga o te whakarite mata ki te angitu o te whakarewa koranu nikara. Ko ngā mahi noa i roto i te umanga matū hinu ko:
– Te tango hinu me te whakamahi i te whakarewa e tika ana hei tango i te hinu/ngako.
– Horoia te waikura mā te whakamahi i tētahi paraihe kowiri tira motuhake (kaua e whakamahi i tētahi paraihe maitai waro).
– Te whakamahinga o ngā taputapu motuhake: me whakatapua ngā huri, ngā kōpae whakakikorua, me ngā paraihe ki ngā rauemi nikara/waikura kore hei ārai i te whakawhiti parahanga.
– Te whakahaere i te taunga me te āputa kia rite tonu hei whakaiti i te tūponotanga o te korenga o te hanumi, te tahunga rānei.
Ahakoa ngā poke iti noa, ka taea e rātou te whakapūpū i te poroustanga me te whakaiti i te kounga o te pīrere whakarewa.
5. Te kōwhiringa o te konganuku whakakī me te hototahitanga
Kaua te kōwhiringa whakarewa whakakī e whakawhirinaki anake ki te kaupapa "he rite te rauemi ki te rauemi". I roto i te mahi matū hinu, he maha ngā wā ka tīpakohia ngā whakakī hei whakapai ake i te ātete ki te pakaru me te waikura. Ngā tauira o ngā kaupapa whānui:
– Whakamahia he whakakī he ātete pai ki te pakaru wera, ā, he hanganga hoki e tautoko ana i te whakapakeketanga pumau.
– Mō te whakarewa rerekē (hei tauira, mai i te koranu nikara ki te kowiri tira, te koranu maitai rānei), ka whiriwhiria he whakakī nikara motuhake e kaha ana ki te tu atu ki te rerekētanga o te whānui wera me te whakaiti i ngā raruraru waimeha.
– Me whakarite kia tutuki te whakakī i ngā paerewa AWS/ASME e tika ana, ā, kia tutuki hoki i ngā whakaritenga o te kaupapa.
I roto i ngā whakamahinga maha, he nui ake te pānga o te waikura i te kaha kume, nō reira ko te kōwhiringa whakakī e pā ana ki te wheako ratonga me ngā taunakitanga waehere.
6. Te whakahaere i te whakauru wera, te whakamahana i mua, me te pāmahana i waenga i te whakawhiti
Kāore e hiahiatia he whakamahana nui mō ngā koranu nikara pērā i ētahi maitai koranu, engari he mea nui tonu te whakahaere i te pāmahana:
– Mā te nui rawa o te wera e whakauru mai ka whānui ake te HAZ (rohe e pāngia ana e te wera), ka nui ake te hē, ka nui ake hoki te tūponotanga o te wehewehenga ka puta ai ngā kapiti wera.
– Me ārai i te pāmahana o waenganui i te ara kia kaua e tino tiketike rawa, kia whakahaeretia ai te hanganga moroiti me te ātete ki te waikura.
– He maha ngā tikanga maha-haerenga me ngā tautuhinga iahiko/ngaohiko pumau e whakamahia ana i runga i ngā pereti matotoru hei pupuri i te kounga.
Ko ngā tawhā tika ka whakatauhia mā te WPS (Welding Procedure Specification) ā, ka whakamatautauria mā te PQR (Procedure Qualification Record).
7. Ngā tikanga whakarewa hei whakaiti i ngā hapa
Ko ētahi tikanga mahi e whakamahia ana mō te whakarewa nikara mō ngā matū hinu:
– He pai ake ngā piripiri aho i te whatu whānui, hei pehi i te wera e uru mai ana, hei whakaiti hoki i te wehewehe.
– He mea tino nui te horoi i waenga i ngā paparanga, inā koa i roto i te SMAW me te SAW, hei ārai i te whakaurunga o te paru.
– Mana tīmata-mutu: me whakakī tika te rua kia kore ai e pakaru te rua.
– Te whakamuri i te whakarewa paipa GTAW (me te argon) kia kore ai e waikura te pūtake pakiaka.
– Te whakamahi i te hau tiaki kounga teitei, me te whakarite kia kore he turuturu e puta ai te waikura, te porosity rānei.
8. Te maimoatanga wera i muri i te whakarewa (PWHT) me ngā whakaaro whakarewa
Kāore e hiahiatia ana he PWHT mō ngā koranu nikara katoa. I roto i te nuinga o ngā wā, ka taea e te PWHT te whakaoho i te maturuturunga iho o ētahi wāhanga, ka taea ai te whakaiti i te ātete ki te waikura, te pakari rānei, i runga i te momo koranu. Nō reira:
– Ka mahia anake te PWHT ina hiahiatia e te waehere (ASME) e te hoahoa rānei, ina hiahiatia rānei e tētahi rauemi.
– Me whai whakaaro te aromatawai i te mōrearea o te maturuturunga iho o te warowaihā/whakarewa ki te pāmahana ratonga me te taiao waikura.
– Mō ētahi whakamahinga, ka hiahiatia pea te whakamahana i roto i te otinga, te maimoatanga wera motuhake rānei, engari ka mahia tēnei i roto i tētahi whare e tika ana, ā, i runga anō i ngā whakaritenga rauemi.
9. Te tirotiro, te whakamātautau me ngā paerewa i whakamahia
I roto i ngā matū hinu, ko te whakarewa i ngā rauemi nikara e whai ana i te ASME Wāhanga IX mō ngā tikanga me ngā tohu a te kaiwhakarewa, me te ASME Wāhanga VIII (ngā oko pēhanga) me te B31.3 rānei (ngā paipa tukanga). Ko ngā tikanga tirotiro noa ko:
– VT (Whakamātautau Tirohanga) hei tirotiro i te āhua o ngā pīri, te tapahi raro, te taupatupatu.
– He whai hua te PT (Whakamātautau Whakauru Wai) mō te kimi i ngā kapiti mata o ngā rauemi kore-ferromagnetic.
– RT/UT hei kite i ngā hapa ā-roto pērā i te pūngao, te korenga o te hanumi, te whakaurunga rānei o te para.
– Tērā pea ka hiahiatia ētahi atu whakamātautau pēnei i te ine i te ferrite (mēnā e tika ana), te whakamātautau pakeke, te whakamātautau waikura rānei, i runga i te ratonga.
He mea tino nui anō hoki te kounga o ngā tuhinga (WPS, PQR, WPQ, te whai i ngā rauemi, te tau wera) i roto i ngā kaupapa matū hinu.
10. Whakamutunga
Ko ngā tikanga whakarewa nikara mō te umanga matū hinu me tino piri ki te horoi, te whiriwhiri tukanga me te whakakī, me te whakahaere i te whakauru wera. He tino pai te mahi a ngā koranu nikara i roto i ngā taiao waikura me te pāmahana teitei, engari ko tō rātou aro ki te poke me te pakaru wera me tino hoahoa me te whakahaere i ngā tikanga whakarewa. Mā te whakatinanatanga tika o te WPS, te whakahaere tawhā, ngā tikanga whakarewa tika, me ngā tirotiro tino tika i runga anō i ngā paerewa ASME, ka taea e ngā hononga whakarewa nikara te whakatutuki i te pono mō te wā roa me te whakaiti i te mōrearea o te rahunga nui o ngā taputapu i roto i ngā whare matū hinu.
Ki te hiahia koe, ka taea e au te whakarite i tēnei tuhinga kia hangarau ake mā te whakauru i ngā tauira o te WPS (te awhe o te au/ngaohiko, te momo hau ārai, te whakawhiti mōrahi), te arotahi rānei ki tētahi koranu motuhake pērā i te Inconel 625, te Hastelloy C-276 rānei.
