Mukuwona 'stellite' pajambula ndipo chinthu choyamba chomwe chimabwera m'maganizo ndi 'cholimba, chosavala, chodula'. Ndiwo pamwamba. Nkhani yeniyeni imayamba mukayesa kuyiyika pamakina, kuwotcherera, kapena kuyambitsa kuponya komwe sikumang'ambika pansi pazovuta zake zamkati. Pali malingaliro olakwika omwe amadziwika kuti chifukwa ndi superalloy yochokera ku cobalt, mwanjira ina yake ndi yunifolomu yamatsenga. M'malo mwake, kusiyana pakati pa mpando wa valavu ya Stellite 6 womwe umatenga zaka khumi ndi womwe umatha chaka chimodzi nthawi zambiri umatsikira ku luso lazoyambira ndi kuthira ndi kutentha kwapambuyo-kutulutsa - tsatanetsatane wazinthu zambiri zogulira zinthu zimawonekera kwathunthu.
Kuthamangitsa Conundrum: Zonse Zili mu Chakudya
Investment casting ndiye kupita ku zovuta Zigawo za stellite alloy, monga turbine blade zisindikizo kapena zida zapampu zovuta. Koma ndi Stellite, malo osungunuka kwambiri komanso mawonekedwe amadzimadzi ndi lupanga lakuthwa konsekonse. Ndikukumbukira pulojekiti yopangira zolimbitsa thupi - zomwe zimapangidwira kupanga chimanga chambewu kuti chiteteze kutopa kwamafuta. Chiphunzitsocho chinali chomveka, koma mchitidwewo unali maloto owopsa a kung'ambika kotentha. Nkhani sinali kapangidwe ka aloyi; chinali njira yolowera ndi yokwera. Tinayenera kuchoka pamapangidwe a mabuku kupita ku chakudya chokulirapo, chotentha kwambiri kuti tithandizire kuchepa kwamphamvu kwa alloy. Sitolo yomwe imagwiritsidwa ntchito popangira zitsulo kapena faifi tambala nthawi zambiri imachepetsa izi, zomwe zimatsogolera ku shrinkage porosity yomwe sitingathe kuizindikira popanda kuyesa kowononga. Ndiko komwe zaka zambiri zachidziwitso chachinsinsi, monga zomwe mungapeze kwa akatswiri ngati Qingdao Qiangsenyuan Technology (QSY), zimakhala zosakambitsirana. Iwo akhala akuyendetsa nkhungu za zipolopolo kwa zaka 30; iwo mwina awona mtundu uliwonse wa shrinkage chilema ndipo ali ndi ndondomeko zosinthidwa kupewa izo.
Chithandizo cha kutentha ndi luso lina lakuda. Njira zochiritsira ndi kukalamba kwa magiredi oumitsa mvula ngati Stellite 21 ndizofunikira. Koma nthawi yokhotakhota yotentha yomwe mumapeza kuchokera kuzinthu zakuthupi? Iwo ndi poyambira. Kuzungulira kwenikweni kumayenera kuwerengera makulidwe a gawo lanu lenileni. Thupi la valve yokhuthala ndi manja a khoma lopyapyala lidzachita mosiyana kwambiri mu ng'anjo yomweyi. Ndawonapo magawo akutuluka ndi kuuma koyenera koma kusokoneza kulimba chifukwa sitoloyo idatsatira maphikidwe a generic. Chotsatira? Gawo lomwe limadutsa QC koma limalephera muutumiki nthawi yake isanakwane. Mufunika wogulitsa yemwe amamvetsetsa zitsulo, osati kungotsatira tchati cha kutentha.
Ndiye pali zopangira athandizira. Sikuti onse 'stellite' amapangidwa mofanana. Zomwe zimagwiritsidwanso ntchito, kuwongolera zinthu (monga kaboni ndi silicon), komanso mawonekedwe a master alloy ingot amatha kukhudza kutayika ndi zomaliza. Wokondedwa wodalirika adzafufuza zomwe asungunula ndikutha kukambirana zotsatira za, mwachitsanzo, 0.5% vs. 0.4% za carbon zomwe zikufunikira pa ntchito yanu yomwe mukufuna kuti musawonongeke ndi machinability.
Machining: Kumene Zida Zimapita Kukafa (Ngati Simusamala)
Ngati mukuganiza kuti makina opanda banga ndi ovuta, Aloyi a stellate ndi ligi yosiyana. Chiwopsezo cha kuuma kwa ntchito ndi chodabwitsa. Kudulira kopepuka, kosamala nthawi zambiri kumatha kuvulaza kwambiri kuposa kuvulaza, kumagwira ntchito molimba komanso kupangitsa kuti kudutsako kukhale kovuta kwambiri. Chinyengo ndi kulowa pansi pa ntchito-yolimba wosanjikiza nthawi yomweyo. Izi zikutanthauza makhazikitsidwe okhwima, osagwedezeka konse, komanso kugwiritsa ntchito magalasi abwino, akuthwa a carbide opangidwira ma aloyi otentha kwambiri. Kuyika kwa Ceramic kapena CBN kumatha kugwira ntchito kuti amalize, koma mtengo wake ndi wokwera ndipo ndi wopepuka.
Kuzizira ndikofunikira, koma osati chifukwa chomwe ambiri amaganiza. Ndizochepa pa kuziziritsa komanso zambiri zamafuta ndi kuchotsa chip. Dongosolo lozizira kwambiri, logwiritsa ntchito zida limafunikira pakubowola kapena mphero. Cholinga chake ndi kuteteza chip kuti chisawotchere mpaka kumapeto, komwe ndi njira yofulumira yopita ku kulephera kwa zida zoopsa. Dry Machining? Ziyiwaleni. Mungotulutsa kutentha kwambiri komwe kumawonjezera gawo lapansi lomwe lili pansi pa kudula kwanu.
Taphunzira izi movutikira pagulu la Stellite 12 zokutira pamitengo ya valve pachipata. Kusindikizaku kunkafuna kutsirizitsa bwino pamwamba pa m'mimba mwake yosindikizira. Kuyesa kwathu koyamba ndi lathe wamba wa CNC ndi choziziritsira madzi osefukira kudapangitsa macheza ndi malo ong'ambika. Yankho silinali lachangu RPM kapena jiometry yosiyana yoyika yokha. Tidayenera kusintha ndondomeko yonseyi: kutembenuka movutikira, kenako kuchotsera kupsinjika (inde, ngakhale mutapanga makina), kenako kumaliza kugaya kuti mufotokozere. Chowonjezeracho chinawonjezera mtengo ndi nthawi, koma inali njira yokhayo yopezera bata ndi kumaliza. Apa ndipamene wogulitsa ndi Integrated CNC makina ndi chidziwitso chazitsulo chimapulumutsa mutu. Amadziwa kuti ndondomekoyi ndi yofunika kwambiri monga njira yopangira zida.
The Welding ndi Overlay Minefield
Kuyang'ana molimba ndi ndodo ya Stellite kapena waya ndikofala, koma kusungunula ndiko kupha mwakachetechete. Ngati chitsulo choyambira (kawirikawiri chitsulo cha kaboni kapena chosapanga dzimbiri) chisungunuka kwambiri ndikusakanikirana ndi chitsulo chowotcherera cha Stellite, mumatsitsa matrix a cobalt ndi chitsulo. Izi zimachepetsa kwambiri kuuma kotentha komanso kukana dzimbiri. Njira yabwino ndi njira yochepetsera pang'ono ngati PTA (Plasma Transferred Arc) kapena laser cladding. Ngakhale ndi izi, kuwongolera parameter ndi chilichonse. Kutentha kwambiri, ndipo mukungopanga aloyi yachitsulo-cobalt yamtengo wapatali, yotsika mtengo.
Ndayang'ana magawo omwe amafunikira 3mm Stellite 6 zokutira, ndipo wosanjikiza bwino, wosasunthika anali wosakwana 1mm atapanga makina. Gawolo likhoza kutha pang'onopang'ono pa moyo woyembekezeredwa. Kukonzekeraku kunaphatikizapo kuwongolera mwamphamvu kwa ma arc voltage, kuthamanga kwaulendo, ndi kuchuluka kwa chakudya cha ufa. Ndi njira yomwe imafuna zolemba ndi kubwereza, osati kungomva kwa wowotcherera.
Post-weld heat treatment (PWHT) ndi malo ena ovuta. Pazigawo zomwe zimafunikira kuti zitsimikizike zitsulo zoyambira (monga zigawo zokhala ndi kukakamiza), kuzungulira kwa PWHT kumatha kukulitsa zopindika za Stellite, kuzifewetsa. Nthawi zina mumayenera kuvomereza kunyengerera kapena kupanga chigawocho kuti malo a Stellite agwiritsidwe ntchito pambuyo pa PWHT yayikulu, yomwe imawonjezera zovuta. Palibe yankho langwiro, kusinthanitsa kocheperako koyipa kokha pazantchito.
Kulephera kwenikweni kwapadziko lonse: Mlandu wa Galvanic Corrosion
Nthawi ina tidaperekako mikono ya Stellite 21 ya pampu yamadzi am'nyanja. Nkhani anasankhidwa zabwino cavitation kukokoloka kukana. Iwo analephera mochititsa chidwi m’miyezi, osati chifukwa cha kuvala, koma chifukwa cha kubowola kwakukulu. Chifukwa chake? Anawalowetsa m'nyumba yazitsulo zosapanga dzimbiri. M'madzi a m'nyanja electrolyte, tinapanga selo lalikulu la galvanic. Stellite wolemekezeka kwambiri (cobalt-based) adakhala ngati cathode, ndipo nyumba zosapanga dzimbiri zosapanga dzimbiri zinakhala anode yoperekera nsembe, kuthamangitsa dzimbiri lake. Phunzirolo linali lankhanza: kusankha zinthu sikungachitike popanda kanthu. Muyenera kuganizira malo onse ochitira msonkhano - madzi, kutentha, komanso, makamaka, zipangizo zina zomwe zimagwirizanitsidwa. Wothandizana naye wabwino amafunsa mafunso amtundu uwu, osati kungovomereza kusindikizidwa kwa gawo limodzi.
Ichi ndichifukwa chake kugwira ntchito ndi katswiri wazinthu zambiri kumakhala komveka. Kampani ngati Mtengo wa QSY, yomwe imagwira ntchito zonse, kuyambira chitsulo chopangidwa ndi nickel mpaka zitsulo za nickel, imatha kuwona zovuta izi msanga. Zomwe amakumana nazo m'mabanja azinthu zimawapatsa malingaliro ochulukirapo azovuta zomwe sitolo ya alloy imodzi ingaphonye.
Kukonzekeraku kunaphatikizapo kukonzanso mawonekedwewo ndi zokutira zotchingira ndikusintha kulolerana koyenera. Zinali kukonzanso kwamtengo wapatali komwe kukanatha kupewedwa ndi kuwunika kwapatsogolo kopanga kupanga. Tsopano, nthawi zonse timafunsa kuti: Kodi zimakhudza chiyani, ndipo chilengedwe ndi chiyani?
Sourcing ndi China Factor
Tiyeni tikhale othandiza. Zambiri zigawo za alloy stellite kusaka kumabweretsa ku China, chifukwa cha mtengo wa cobalt yaiwisi komanso njira zogwirira ntchito. Mantha nthawi zonse amakhala osasinthasintha. Chosiyanitsa chachikulu si dziko, ndi kukhwima kwa magwiridwe antchito a maziko enieni. Mufunika umboni wa kayendetsedwe ka kayendetsedwe kake: machitidwe ovomerezeka a kusungunula, ma chart ovomerezeka a kutentha kwa batch iliyonse, ndi NDT yolimba (monga ma FPI a ming'alu ya pamwamba pazigawo zovuta).
Webusaiti ngati tsngtaocnc.com ikuwonetsa mbiri yakale yogwira ntchito (zaka 30+) ndikuyang'ana kwambiri zipolopolo ndi kuponya ndalama. Kukhala ndi moyo wautali mu niche iyi ndi chizindikiro. Zikuwonetsa kuti ayenda pamapindikira ophunzirira pazitsulo zachinyengo ndipo asungabe luso lopanga mapatani ndi ma metallurgist omwe amafunikira. Mayeso enieni ali muzokambirana zawo zamakono. Kodi angakambirane za kutentha kusanayambe kutentha kwa Stetellite 1 mpaka 410 zosapanga dzimbiri? Kodi angapangire makina otsatizana a mphete yopyapyala ya Stellite 3? Mayankho awo ku mafunsowa amakuuzani zambiri kuposa satifiketi iliyonse.
Pamapeto pake, mbali zopambana za Stellite zimachokera ku kuchitira aloyi molemekeza zovuta zake. Sizitsulo zamtengo wapatali. Pamafunika ubale wa symbiotic pakati pa wopanga, metallurgist, ndi wamakina. Cholinga chake ndikukulitsa katundu wake wodabwitsa popanda kugonjetsedwa ndi zovuta zake zopanga. Ogulitsa omwe amapeza izi ndi omwe adadutsa pamoto-kwenikweni ndi mophiphiritsira-wa ng'anjo yoponyera ng'anjo ndi malo opangira makina, ndipo ali ndi njira zothandizira, nthawi zina zovuta, zowonetsera.
