Ka Whakaroahia te Ora e te Rautaki Whakahaere Mekameka AFC, ka Ārai hoki i te Wā Whakamutu Kāore i Whakaritea
mekameka kerika taea te whakapai, te whakakore rānei i tētahi mahi. Ahakoa te nuinga o ngā maina pakitara roa e whakamahi ana i te mekameka 42 mm, neke atu rānei, i runga i ā rātou kawe mata ārai (AFC), he maha ngā maina e whakahaere ana i te 48-mm, ā, ko ētahi e whakahaere ana i te mekameka tae atu ki te 65 mm te rahi. Ka taea e ngā diameter nui ake te whakaroa i te roa o te mekameka. He maha ngā kaiwhakahaere pakitara roa e tumanako ana kia neke atu i te 11 miriona tana me ngā rahi 48-mm, tae atu ki te 20 miriona tana me ngā rahi 65-mm i mua i te whakakorenga o te mekameka. He utu nui te mekameka i roto i ēnei rahi nui engari he pai te utu mēnā ka taea te keri i tētahi panera katoa, e rua rānei, me te kore e kati nā te pakaru o te mekameka. Engari, mēnā ka pakaru te mekameka nā te whakahaere hē, te whakahaere hē, te aroturuki hē, nā ngā āhuatanga taiao rānei ka puta ai te pakaru waikura ahotea (SCC), ka raru nui te maina. I roto i tēnei āhuatanga, ka kore he utu mō taua mekameka.
Mena kāore te kaiwhakahaere taiepa roa e whakahaere ana i te mekameka pai rawa atu mō ngā āhuatanga o te maina, mā te kati ohorere ka taea te whakakore i ngā penapena utu i kohia i te wā o te tukanga hoko. Nō reira, me aha te kaiwhakahaere taiepa roa? Me aro nui rātou ki ngā āhuatanga motuhake o te papaanga, ā, me whiriwhiri marie i tētahi mekameka. I muri i te hokonga o te mekameka, me whakapau e rātou he wā me te moni tāpiri e tika ana hei whakahaere tika i te haumitanga. Ka taea e tēnei te utu nui.
Ka taea e te whakamahana te whakanui ake i te kaha o te mekameka, te whakaiti i tōna pakarukaru, te whakamamae i ngā ahotea o roto, te whakanui ake i te ātete ki te kakahu, te whakapai ake rānei i te ngāwari o te mekameka ki te miihini. Kua noho te whakamahana hei momo toi ataahua, ā, he rerekē i ia kaihanga ki ia kaihanga. Ko te whāinga he whiwhi i te taurite o ngā āhuatanga whakarewa kia pai ai te mahi a te hua. Ko te mekameka whakapakeke rerekē tētahi o ngā tikanga matatau e whakamahia ana e te mekameka Parsons, kei reira te karauna o te hononga mekameka e noho uaua tonu ana ki te ātete ki te kakahu, ā, ki te ngawari ake ngā hononga, ka whakanui ake i te pakari me te ngāwari o te mahi.
Ko te pakeketanga ko te kaha ki te ātete i te kakahu, ā, e tohuhia ana e te tau pakeketanga Brinell mā te tohu HB, mā te tau pakeketanga Vickers rānei (HB). He tino ōrite te tauine pakeketanga Vickers, nō reira, he waru ngā wā he pakeke ake te rauemi 800 HV i te mea he pakeketanga 100 HV. Nō reira, ka whakaratohia he tauine pakari mai i te rauemi ngawari ki te rauemi tino mārō. Mō ngā uara pakeketanga iti, tae atu ki te 300, he rite tonu ngā hua pakeketanga Vickers me Brinell, engari mō ngā uara teitei ake, he iti ake ngā hua Brinell nā te whakapōturitanga o te kōhao pōro.
Ko te Whakamātautau Pānga Charpy he ine i te pakarukaru o tētahi rauemi ka taea te tiki mai i tētahi whakamātautau pānga. Ka tapahia te hononga mekameka ki te pūwāhi whakarewa o te hononga, ka whakatakotoria ki te ara o te pendulum e piu ana, ko te kaha e hiahiatia ana hei whati i te tauira ka inehia mā te whakaiti i te piu o te pendulum.
Ko te nuinga o ngā kaihanga mekameka e penapena ana i ētahi mita o ia ota puranga kia taea ai te whakahaere i te whakamātautau whakangaro katoa. Ko ngā hua whakamātautau katoa me ngā tiwhikete ka tukuna tahitia me te mekameka, e tukuna ana i roto i ngā takirua ōrite 50-m. Ka tuhia hoki te roa i te kaha whakamātautau me te roa katoa i te whati i roto i tēnei whakamātautau whakangaro.
Te Mekameka Tino Pai
Ko te whāinga he whakakotahi i ēnei āhuatanga katoa hei hanga i te mekameka tino pai, tae atu ki ēnei mahi e whai ake nei:
• Te kaha kume teitei ake;
• He ātete teitei ake ki te pakaru o ngā hononga o roto;
• Te ātete nui ki te kino o te sprocket;
• He ātete nui ake ki te pakaru martensitic;
• Te pakari kua whakapaitia;
• Te roa o te ora mō te ngenge; me
• Te ātete ki te SCC.
Heoi, kāore he otinga tino tika kotahi, engari he maha ngā huarahi hei whakatau. Ka hua ake he ahotea toenga nui i te pūwāhi hua teitei, engari ki te honoa ki te pakeketanga teitei hei whakanui ake i te ātete ki te kakahu, ka heke anō hoki te pakari me te ātete ki te waikura ahotea.
Kei te whai tonu ngā kaihanga ki te whakawhanake i te mekameka ka roa ake te oma, ā, ka ora i ngā āhuatanga uaua. Ka whakakahangia e ētahi kaihanga te mekameka kia pai ai te mahi ki ngā taiao waikura. Ko tētahi atu kōwhiringa ko te mekameka COR-X, he mea hanga mai i te koranu vanadium, nickel, chromium, me te molybdenum kua patenttia hei whawhai ki te SCC. Ko te mea e motuhake ai tēnei otinga ko te ōrite o ngā āhuatanga waikura ātete-aukati puta noa i te hanganga whakarewa o te mekameka, ā, kāore tōna whai huatanga e rerekē i te wā e memeha haere ana te mekameka. Kua whakamātauhia e COR-X te whakanui ake i te roa o te mekameka i roto i ngā taiao waikura, ā, tata kore rawa e pakaru nā te waikura ahotea. Kua whakaūhia e ngā whakamātautau ka piki ake te kaha pakaru me te mahi mā te 10%. Ka piki ake te pānga o te notch mā te 40%, ā, ka piki ake te ātete ki te SCC mā te 350% ki te whakaritea ki te mekameka noa (DIN 22252).
Tērā ētahi wā kua oma te mekameka COR-X 48 mm i te 11 miriona tana, kāore he pakaru e pā ana ki te mekameka i mua i te whakakorenga. Ā, ko te whakaurunga tuatahi o te mekameka OEM Broadband e Joy i te maina BHP Billiton San Juan i whakahaere i te mekameka Parsons COR-X i hangaia i te UK, e kiia ana i kawe i te 20 miriona tana mai i te mata i roto i tōna oranga.
Mekameka Whakamuri hei Whakaroa i te Ora o te Mekameka
Ko te tino take o te pakaru o te mekameka ko te nekehanga o ia hononga poutū e hurihuri ana i tōna hononga whakapae e tata ana i a ia e tomo ana, e puta atu ana hoki i te poroka taraiwa. Ka hua ake hoki tēnei i te pakaru nui ake o tētahi papa o ngā hononga i a rātou e hurihuri ana i roto i te poroka, nō reira ko tētahi o ngā huarahi tino whai hua ki te whakaroa i te roa o te ora o tētahi mekameka kua whakamahia ko te hurihuri, te huri rānei i te 180º hei whakahaere i te mekameka ki te taha ke. Mā tēnei ka mahi ngā mata "kāore i whakamahia" o ngā hononga, ā, ka iti ake te pakaru o te rohe hononga, ā, ka roa ake te ora o te mekameka.
Nā te maha o ngā take, ka kore e ōrite te uta o te kaikawe, ka kore e ōrite te kakahu o ngā mekameka e rua, ka tere ake te kakahu o tētahi mekameka i tētahi atu. Mā te kore e ōrite te kakahu, te totoro rānei o tētahi, o ngā mekameka e rua rānei, pērā i ngā huihuinga takirua o waho, ka kore e ōrite ngā rerenga, ka kore rānei e tika te hikoi i a rātou e haereere ana i te poroka taraiwa. Tērā pea ka ngoikore tētahi o ngā mekameka e rua. Mā tēnei pānga kore taurite ka raru te mahi, ka nui rawa te kakahu me te kino pea o ngā poroka taraiwa.
Te Whakapūmautanga Pūnaha
Me whai kaupapa whakapūmau me te tiaki pūnaha kia taea ai te whakahaere i te tere o te kakahu o te mekameka i muri i te tāutanga, kia taea ai te whakaroa i ngā mekameka e rua nā te kakahu i tētahi tere e taea ai te whakahaere, ā, kia rite tonu hoki.
I raro i tētahi kaupapa tiaki, ka ine ngā kaimahi tiaki i te pakaru o te mekameka me te taumahatanga, ka whakakapia te mekameka ina neke atu i te 3%. Hei mārama ki te tikanga o tēnei nui o te pakaru o te mekameka, me mahara ko te pakaru o te mekameka he 3% te roa, ka piki ake te roa o te mekameka ki te 12 m mō ia miro. Ka whakakapia hoki e ngā kaimahi tiaki ngā porotiti me ngā mīhini tango mekameka ina pakaru, ina pakaru rānei ēnei, ka tirohia te pouaka miihini me te taumata hinu, ā, me whakarite, i ngā wā katoa, kia mau tonu ngā pūtu.
He maha ngā tikanga kua whakapumautia mō te tatau i te taumata tika o te pēhanga, ā, he aratohu tino whai hua ēnei ki ngā uara tīmatanga. Heoi, ko te tikanga tino pono ko te tirotiro i te mekameka i a ia e wehe atu ana i te pīkau taraiwa ina mahi ana te AFC i raro i ngā āhuatanga kawenga katoa. Me kite te mekameka he iti noa te ngoikore (e rua ngā hononga) i a ia e wehe atu ana i te pīkau taraiwa. Ina puta he taumata pēnei, me ine, me tuhi, me whakatakoto hoki te pēhanga mō te heke mai hei taumata whakahaere mō taua mata. Me tango tonu ngā pānui pēhanga i ia wā, ā, me tuhi te maha o ngā hononga kua tangohia. Mā tēnei ka whakatūpato wawe mō te tīmatanga o te kakahu rerekē, te kakahu nui rawa rānei.
Me whakatika, me whakarerekē rānei ngā rerenga piko i te wā tonu. Ka whakaitihia te mahi a te kaikawe, ā, ka taka pea te pae i waho o te reihi o raro, ka peke ki runga i te whīra, ka pakaru ai ngā mekameka, te whīra, me ngā pae rerenga.
Me tūpato tonu ngā kaiwhakahaere pakitara roa ki ngā mīhini whiri mekameka kua pakaru, kua tawhito hoki, nā te mea ka waiho pea te mekameka ngoikore kia noho tonu i roto i te porotiti, ā, ka hua ake pea he aukati, he pakaru rānei.
Ka Tīmata te Whakahaere Mekameka i te Wā Tāutanga
Kāore e taea te whakanui rawa i te hiahia mō tētahi rārangi mata tika. Mēnā he rerekē te āhua o te mata, tera pea ka rerekē te āhua i waenga i ngā mekameka mata-taha me ngā mekameka taha-kōpiko, ā, ka kore e ōrite te mau. He nui ake te tūponotanga ka puta tēnei i runga i te mata hou i te mea kei roto ngā mekameka i te wā "whakaurunga".
Kia puta rā anō te tauira kakahu rerekē, kāore e taea te whakatika. He maha ngā wā ka kino haere tonu te rerekētanga me te mau o te mekameka ngoikore, ka nui ake te ngoikore.
Mā te arotake i ngā tau ka kitea ngā pānga kino o te oma me te rārangi mata ngoikore e arahi ana ki ngā rerekētanga nui o te taha mō ngā whakapūmautanga taha. Hei tauira, he pakitara roa 1,000-putu te roa me te mekameka AFC 42-mm e tata ana ki te 4,000 hononga i ia taha. Mā te whakaae ka puta te tango i te whakarewa pakaru hononga i ngā pito e rua o te hononga. E 8,000 ngā pūwāhi o te mekameka e pakaru ai te whakarewa i ngā pēhanga hononga i a ia e peia ana, e wiri ana i te mata, e pāngia ana e te uta ru, e pāngia ana rānei e te whakaeke waikura. Nō reira, mō ia 1/1,000-inihi o te pakaru ka puta he 8 inihi te pikinga o te roa. Ko tētahi rerekētanga iti i waenga i te reiti pakaru o te taha mata me te taha gob, i puta mai i ngā taumahatanga kore taurite, ka tere te whakanui ake ki tētahi rerekētanga nui o te roa o te mekameka.
Mā te rua o ngā whakapūtanga i te porotiti i te wā kotahi ka arahi pea ki te pakaru nui o te kōtaha niho. Nā te ngaronga o te tūranga pai i roto i te porotiti taraiwa tēnei, ka taea ai e te hononga te paheke ki runga i ngā niho taraiwa. Ka tapahia e tēnei mahi paheke te hononga, ā, ka piki ake hoki te tere pakaru o ngā niho porotiti. Kia whakapumautia hei tauira pakaru, ka taea anake te tere ake. I te tohu tuatahi o te tapahi o te hononga, me tirotirohia ngā porotiti, ā, me whakakapi mēnā e tika ana, i mua i te pakaru o te mekameka i te kino.
Ki te nui rawa te pēhanga mekameka, ka nui rawa te pakaru o te mekameka me te porotiti. Me whakatū ngā pēhanga mekameka ki ngā uara e ārai ana i te hanga o te mekameka ngoikore rawa i raro i te kawenga katoa. Mā ēnei āhuatanga ka taea te "peke atu" i ngā pae waruwaru me te mōrearea o te pakaru o te porotiti hiku nā te hononga mekameka i a ia e wehe atu ana i te porotiti. Ki te nui rawa te pēhanga, e rua ngā tūponotanga e kitea ana: te nui rawa o te pakaru i waenga i ngā hononga o te mekameka, me te nui rawa o te pakaru o ngā porotiti taraiwa.
Ka taea e te taumahatanga mekameka nui te whakamate
Ko te tikanga noa ko te whakahaere i te mekameka kia tino kikī rawa. Ko te whāinga kia tirohia tonutia te piko me te tango i te mekameka ngoikore mā te rua ngā hononga. Mēnā neke atu i te rua ngā hononga, ka tohu he tino ngoikore te mekameka, ki te tangohia rānei ngā hononga e whā, ka nui rawa te piko ka puta he pakaru nui i waenga i ngā hononga, ā, ka tino whakaiti i te roa o te ora o te mekameka.
Ki te pai te tūnga o te mata, kaua te uara o te pēhanga i tētahi taha e neke atu i te kotahi tana i te uara o tērā taha. Mā te whakahaere mata pai ka taea te pupuri i tētahi rerekētanga kia kaua e neke atu i te rua tana puta noa i te roanga o te mahi a te mekameka.
Ka taea te tuku i te roa haere o te mekameka nā te kakahu o ngā hononga (e kiia hētia ana ko te "totoro mekameka") kia eke ki te 2%, me te whakahaere tonu me ngā pīkau hou.
Kāore he raruraru o te nui o te pakaru o ngā hononga mēnā ka pakaru ngātahi te mekameka me ngā pīkau, ā, ka mau tonu te hototahitanga. Heoi anō, ka whakaitihia te kawenga pakaru o ngā mekameka me te ātete ki ngā kawenga ru e te pakaru o ngā hononga.
Ko tētahi tikanga māmā mō te ine i te pakaru o ngā hononga ko te whakamahi i tētahi caliper, e ine ana i ngā wāhanga piko e rima, ka tāpirihia ki te tūtohi roa o te mekameka. Ko te tikanga, ka whakaarohia ngā mekameka kia whakakapia ina neke atu i te 3% te pakaru o ngā hononga. Kāore ētahi kaiwhakahaere tiaki matatika e pai kia neke atu i te 2% te roa o tā rātou mekameka.
Ka tīmata te whakahaere pai o te mekameka i te wā tāutanga. Mā te aroturuki kaha me ngā whakatikatika mēnā e tika ana i te wā e whakatōngia ana te mekameka ka roa te ora, ka kore he raruraru.
(Me te manaakitanga oEllton Longwall)
Wā tuku: Hepetema-26-2022
