Ma protocol osiyanasiyana oyesera (Brinell, Rockwell, Vickers) ali ndi njira zoyendetsera polojekiti yomwe ikuyesedwa.Mayeso a Rockwell T ndi oyenera kuyang'ana machubu a khoma la kuwala podula chubu motalika ndikuyesa khoma kuchokera mkati mwake osati m'mimba mwake.
Kuyitanitsa chubu kuli ngati kupita kumalo ogulitsa magalimoto ndi kuyitanitsa galimoto kapena galimoto. Lero, zosankha zambiri zomwe zilipo zimalola ogula kusintha galimotoyo mosiyanasiyana - mitundu ya mkati ndi kunja, phukusi lamkati, masitayelo akunja, zosankha za powertrain, ndi makina omvera omwe amafanana ndi dongosolo la zosangalatsa zapanyumba.
Kuonjezera pa miyeso, ndondomekoyi imatchula mankhwala ndi zinthu zingapo zamakina monga mphamvu zochepa zokolola (MYS), mphamvu zowonongeka kwambiri (UTS), komanso elongation yochepa isanalephereke.
Yesani kuyitanitsa galimoto ndi chikhalidwe chimodzi ("Ndikufuna galimoto yokhala ndi makina opangira magetsi") ndipo simudzafika patali ndi wogulitsa.Ayenera kudzaza fomu yoyitanitsa ndi zosankha zambiri.Pipe ndizomwezo - kuti apeze chitoliro choyenera chogwiritsira ntchito, wopanga chitoliro amafunikira zambiri kuposa kuuma kokha.
Kodi kuuma kumakhala bwanji kovomerezeka m'malo mwa makina ena? Mwinamwake kudayamba ndi wopanga chitoliro. Chifukwa kuyesa kuuma kumakhala kofulumira, kosavuta, ndipo kumafuna zida zotsika mtengo, ogulitsa machubu nthawi zambiri amagwiritsa ntchito kuyesa kuuma kuyerekeza machubu awiri.
Kuuma kwa chubu kumayenderana bwino ndi UTS, ndipo monga lamulo la chala chachikulu, maperesenti kapena kuchuluka kwa magawo ndizothandiza pakuyerekeza MYS, kotero ndikosavuta kuwona momwe kuyezetsa kuuma kungakhalire projekiti yoyenera pazinthu zina.
Komanso, mayesero ena ndi ovuta.Ngakhale kuyesa kuuma kumatenga mphindi imodzi kapena kuposerapo pamakina amodzi, MYS, UTS ndi kuyezetsa elongation kumafuna kukonzekera kwachitsanzo ndi ndalama zazikuluzikulu za labotale.Monga kufananiza, zimatenga masekondi kuti woyendetsa chubu ayese kuuma ndi maola kuti katswiri wazitsulo azitha kuyesa kuyesa kolimba sikovuta.
Izi sizikutanthauza kuti opanga mapaipi opangidwa ndi makina sagwiritsa ntchito kuyesa kuuma. Ndi zotetezeka kunena kuti anthu ambiri amatero, koma chifukwa amayesa kubwereza ndi kubwerezabwereza ndi kubwerezabwereza pazida zawo zonse zoyesera, amadziwa bwino zofooka za mayeso.
Chifukwa chiyani muyenera kudziwa za MYS, UTS ndi elongation yocheperako? Amawonetsa momwe chubu idzakhalira pakusonkhana.
MYS ndi mphamvu yochepa yomwe imayambitsa kusinthika kosatha kwa zinthuzo.Ngati muyesa kupindika waya wowongoka (monga chovala cha malaya) pang'ono ndikumasula kupanikizika, chimodzi mwa zinthu ziwiri chidzachitika: chidzabwerera ku chikhalidwe chake choyambirira (chowongoka) kapena chidzakhala chopindika.Ngati chikadali chowongoka, simunadutse MYS.Ngati idakali yopindika, mwadutsa.
Tsopano, gwiritsani ntchito pliers kuti mutseke malekezero onse a waya.Ngati mungathe kung'amba waya mu zidutswa ziwiri, mwadutsa UTS.Mumayika zovuta zambiri pa izo ndipo muli ndi mawaya awiri kuti muwonetse mphamvu zanu zopambana zaumunthu.Ngati kutalika koyambirira kwa waya ndi mainchesi 5, ndipo kutalika kwawiri pambuyo pa kulephera kumawonjezera mpaka 6 mainchesi, waya woyezetsa wa 2 inchi wotambasulidwa mkati mwa 2 inchi. mfundo yolephera, koma zilizonse - lingaliro la waya wokoka likuwonetsa UTS.
Zitsanzo zachitsulo za photomicrograph ziyenera kudulidwa, kupukutidwa, ndi kuziyika pogwiritsa ntchito njira ya acidic pang'ono (kawirikawiri nitric acid ndi mowa (nitroethanol)) kuti njere ziwoneke.100x magnification amagwiritsidwa ntchito poyang'ana njere zachitsulo ndikuzindikira kukula kwa mbewu.
Kuuma ndi kuyesa momwe zinthu zimayankhira kukhudzidwa.Tangoganizirani kuika kachidutswa kakang'ono ka chitoliro mu vise ndi nsagwada zowonongeka ndi kutembenuza nsagwada kuti zitseke.Kuphatikiza pa kupukuta chubu, nsagwada za vise zimasiyanso zozungulira pamwamba pa chubu.
Umu ndi momwe kuyesa kuuma kumagwirira ntchito, koma sikuli kovuta kwambiri.Kuyesaku kumakhala ndi kukula kwake kolamuliridwa ndi kukakamizidwa kolamuliridwa.Makani awa amasokoneza pamwamba, kupanga indentation kapena indentation.Kukula kapena kuya kwa indentation kumatsimikizira kuuma kwachitsulo.
Pakuwunika chitsulo, mayeso olimba omwe wamba ndi Brinell, Vickers, ndi Rockwell. Iliyonse ili ndi sikelo yake, ndipo ena ali ndi njira zingapo zoyesera, monga Rockwell A, B, ndi C. Pa mapaipi achitsulo, ASTM Specification A513 imanena za mayeso a Rockwell B (ofupikitsidwa ngati HRB kapena RB). Mayeso a Rockwell B amayesa kusiyana kwa chitsulo chodzaza ndi 16- ⁄ chitsulo cholowetsa m'mimba mwake yaing'ono 16- ⁁ chitsulo cholowera pang'ono. katundu wa 100 kgf. Chotsatira chodziwika bwino chachitsulo chofatsa ndi HRB 60.
Asayansi azinthu amadziwa kuti kuuma kumayenderana ndi UTS.Chifukwa chake, kuuma kopatsidwa kungathe kuneneratu UTS.Momwemonso, opanga ma chubu amadziwa kuti MYS ndi UTS ndi zokhudzana.Kwa chitoliro chowotcherera, MYS nthawi zambiri imakhala 70% mpaka 85% ya UTS.Kuchuluka kwake kumadalira ndondomeko yopangira chubu.Kulimba kwa HRB 0s0 PS 600 Square pounds, UTS 600 paundi ) ndi MYS ya 80%, kapena 48,000 PSI.
Chitoliro chodziwika bwino cha chitoliro pakupanga kwakukulu ndizovuta kwambiri.Kuphatikiza ndi kukula kwake, injiniyayo ankakhudzidwa ndi kufotokozera chitoliro cha welded electric resistance welded (RW) mkati mwa njira yabwino yogwirira ntchito, zomwe zingayambitse kuuma kwakukulu kwa mwina HRB 60 kupeza njira yake pa chigawo chojambula.
Choyamba, kuuma kwa HRB 60 sikumatiuza zambiri.Kuwerenga HRB 60 ndi nambala yopanda malire. Zomwe zimayesedwa ndi HRB 59 ndizofewa kuposa zomwe zimayesedwa ndi HRB 60, ndipo HRB 61 ndizovuta kuposa HRB 60, koma ndi zochuluka bwanji? malo (kuyezedwa patali poyerekeza ndi nthawi), kapena UTS (kuyezedwa mu mapaundi pa inchi lalikulu).Kuwerenga HRB 60 sikumatiuza chilichonse chodziwika.Ichi ndi katundu wa zinthu, koma osati katundu wakuthupi.Chachiwiri, kuyesa kuuma sikuli koyenera kubwereza kapena kuberekanso.Kuwunika malo awiri pa chitsanzo choyesera,Kuwerengera kumakhala kofupikitsa kuwerengera kwakukulu kwa malo ena. ndi chikhalidwe cha mayesowo.Pamene malo ayesedwa, sangathe kuyezedwa kachiwiri kuti atsimikizire zotsatira.Kubwereza kuyesa sikutheka.
Izi sizikutanthauza kuti kuyezetsa kuuma kumakhala kovuta.M'malo mwake, amapereka chitsogozo chabwino cha UTS yazinthu, ndipo ndi mayeso ofulumira komanso osavuta.
Chifukwa chitoliro "chabwinobwino" sichimafotokozedwa bwino, pakafunika, opanga zitoliro nthawi zambiri amachichepetsa mpaka pamitundu iwiri yazitsulo zomwe zimagwiritsidwa ntchito kwambiri mu ASTM A513: 1008 ndi 1010.
Mwachitsanzo, chubu imafotokozedwa kuti ndi yofewa ngati MYS ndi yochepa komanso kutalika kwake ndipamwamba, zomwe zikutanthauza kuti zimagwira ntchito bwino kwambiri, zowonongeka ndi zowonongeka kusiyana ndi chubu chofotokozedwa ngati cholimba, chomwe chimakhala ndi MYS yapamwamba kwambiri komanso yotsika kwambiri.
Elongation palokha ndi chinthu china chimene chimakhudza kwambiri chitoliro applications.Tubes ndi elongation mkulu akhoza kupirira kumakoka mphamvu;zipangizo zokhala ndi elongation yochepa zimakhala zowonongeka kwambiri ndipo motero zimakhala zovuta kwambiri kulephera kwamtundu wa kutopa.
Chifukwa chiyani makina amachubu amasiyana kwambiri?Choyamba, kapangidwe kake ndi kosiyana.Chitsulo ndi njira yolimba yachitsulo ndi kaboni ndi ma aloyi ena ofunikira.Kusavuta, tidzangothana ndi magawo a carbon pano.Maatomu a carbon amalowa m'malo ena mwa maatomu achitsulo, kupanga mawonekedwe a chitsulo.ASTM 1008 ndi gawo la 1% lokhala ndi gawo lapadera la 0% lokhala ndi gawo lapadera la 0% lokhala ndi gawo lapadera la 0%. imapanga zinthu zapadera pamene mpweya wa carbon muzitsulo ndi wotsika kwambiri.ASTM 1010 imatchula mpweya wa carbon pakati pa 0.08% ndi 0.13%.
Chachiwiri, chitoliro chachitsulo chikhoza kupangidwa kapena kupangidwa ndikukonzedwanso m'njira zisanu ndi ziwiri zosiyana zopangira.ASTM A513 yokhudzana ndi kupanga mapaipi a ERW imatchula mitundu isanu ndi iwiri:
Ngati mankhwala a zitsulo ndi machubu opangira machubu alibe mphamvu pa kuuma kwa chitsulo, ndi chiyani?Kuyankha funso ili kumatanthauza kusanthula zambiri.
Tsatanetsatane wa njere zomwe zimapanga chitsulo ndi yankho loyamba.Chitsulo chikapangidwa pa mphero yachitsulo choyambirira, sichimazizira mu chipika chachikulu chokhala ndi chinthu chimodzi.Chitsulocho chikazizira, mamolekyu achitsulo amapangidwa mobwerezabwereza (makhiristo), mofanana ndi momwe ma snowflakes amapangidwira.Makristali akapangidwa, amaphatikizana m'magulu otchedwa mbewu, mbale yomaliza imamera monga mbewu, pepala lomaliza kapena zitsulo zomaliza. s zimatengeka ndi njerezo. Zonsezi zimachitika pamlingo wa microscopic chifukwa kukula kwake kwa chitsulo kumakhala pafupifupi 64 µ kapena 0.0025 mainchesi m'lifupi. Ngakhale njere iliyonse ndi yofanana ndi yotsatira, iwo sali ofanana. Amasiyana pang'ono kukula kwake, maonekedwe ndi mpweya wa carbon. Kulumikizana pakati pa njere kumatchedwa malire a tirigu.
Kodi muyenera kuyang'ana patali bwanji kuti muwone mbewu zowoneka bwino? Kukula kwa 100x, kapena masomphenya a 100x aumunthu, ndi okwanira. Komabe, kungoyang'ana zitsulo zosagwiritsidwa ntchito nthawi 100 mphamvu sizimawululira zambiri.Chitsanzocho chimakonzedwa ndi kupukuta chitsanzo ndi kupukuta pamwamba ndi asidi (kawirikawiri nitric acid ndi mowa) wotchedwa nitroethanol eti nitroethanol
Ndi njere ndi zitsulo zawo zamkati zomwe zimatsimikizira mphamvu ya mphamvu, MYS, UTS ndi elongation yomwe chitsulo chingathe kupirira chisanalephereke.
Masitepe opangira zitsulo, monga kugudubuzika kotentha ndi kozizira, amaika kupsinjika mumpangidwe wambewu;ngati asinthiratu mawonekedwe, izi zikutanthauza kuti kupsinjika kumawononga njere. Njira zina zopangira, monga kukulunga zitsulo kukhala zomangira, kuzimasula, ndi kusokoneza njere zachitsulo kudzera mu chubu (kupanga ndi kukula kwa chubu). Kuzizira kujambula chubu pa mandrel kumapangitsanso kupanikizika pazinthu, monga momwe zimakhalira kupanga masitepe monga mapeto a kupanga ndi kupindika. Kusintha kumatchedwa dislocation structure
Masitepe omwe ali pamwambawa amachepetsa ductility yachitsulo, yomwe ndi mphamvu yake yolimbana ndi zovuta (kukoka-kutsegula) kupsinjika.Chitsulo chimakhala chosasunthika, chomwe chimatanthawuza kuti ndi chotheka kusweka ngati mukupitirizabe kugwira ntchito. amapangidwa mosavuta pansi pa kupsinjika maganizo - ndi ductile - yomwe ndi mwayi.
Konkire imakhala ndi mphamvu zopondereza kwambiri koma ductility yochepa poyerekeza ndi konkire.Zinthuzi zimatsutsana ndi zitsulo.Ndicho chifukwa chake konkire yomwe imagwiritsidwa ntchito pamisewu, nyumba ndi misewu nthawi zambiri imakhala ndi rebar.Chotsatira chake ndi mankhwala omwe ali ndi mphamvu za zipangizo ziwiri: pansi pa zovuta, zitsulo zimakhala zolimba, ndipo pansi pa kupanikizika, konkire.
Panthawi yogwira ntchito yozizira, pamene ductility ya chitsulo imachepa, kuuma kwake kumawonjezeka.Mwa kuyankhula kwina, idzaumitsa.Malingana ndi momwe zinthu zilili, izi zingakhale zopindulitsa;komabe, zingakhale zovuta chifukwa kuuma kumafanana ndi brittleness.Ndiko kuti, pamene chitsulo chimakhala cholimba, chimakhala chochepa;chifukwa chake, ndizotheka kulephera.
Mwa kuyankhula kwina, sitepe iliyonse ya ndondomeko imagwiritsa ntchito ductility ya chitoliro.Imakhala yovuta pamene gawolo likugwira ntchito, ndipo ngati liri lolimba kwambiri ndilopanda phindu.Kulimba ndi brittleness, ndipo chubu chophwanyika chikhoza kulephera pamene chikugwiritsidwa ntchito.
Kodi wopanga ali ndi njira iliyonse pankhaniyi? Mwachidule, inde. Njirayi ndiyosavuta, ndipo ngakhale sizodabwitsa, ili pafupi ndi matsenga momwe mungapezere.
M'mawu a layman, annealing amachotsa zotsatira zonse za kupsinjika kwa thupi pazitsulo.Mchitidwewu umatenthetsa zitsulo ku kupsinjika maganizo kapena kutentha kwa recrystallization, potero kuchotsa kusokonezeka.Kutengera kutentha kwapadera ndi nthawi yomwe imagwiritsidwa ntchito popanga annealing, ndondomekoyi imabwezeretsanso zina kapena zonse za ductility.
Kuziziritsa ndi kuziziritsa koyendetsedwa kumalimbikitsa kukula kwa tirigu. Izi ndi zopindulitsa ngati cholinga chake ndikuchepetsa kuwonongeka kwa zinthu, koma kukula kosalamulirika kwa njere kumatha kufewetsa chitsulo mochuluka, kupangitsa kuti zisagwiritsidwe ntchito pazantchito zake.
Kodi tiyenera kusiya kuuma specifications?
Komabe, si mayeso enieni oyenerera (kuvomereza kapena kukana) zinthu. Kuphatikiza pa kuuma, opanga nthawi ndi nthawi ayenera kuyesa kutumiza kuti adziwe zinthu zina zoyenera, monga MYS, UTS, kapena kutalika kochepa, malingana ndi kugwiritsa ntchito chubu.
Wynn H. Kearns is responsible for regional sales for Indiana Tube Corp., 2100 Lexington Road, Evansville, IN 47720, 812-424-9028, wkearns@indianatube.com, www.indianatube.com.
Tube & Pipe Journal inakhala magazini yoyamba yoperekedwa kuti itumikire mafakitale azitsulo zazitsulo mu 1990.Today, imakhalabe buku lokhalo ku North America loperekedwa ku makampani ndipo lakhala gwero lodalirika la chidziwitso kwa akatswiri a chitoliro.
Tsopano ndi mwayi wofikira ku mtundu wa digito wa The FABRICATOR, mwayi wosavuta kuzinthu zamakampani.
Magazini ya digito ya The Tube & Pipe Journal tsopano ikupezeka bwino, ikupereka mwayi wosavuta kuzinthu zofunikira zamakampani.
Sangalalani ndi mwayi wofikira ku STAMPING Journal ya digito, yomwe imapereka kupita patsogolo kwaukadaulo kwaposachedwa, machitidwe abwino kwambiri komanso nkhani zamakampani pamsika wopondaponda zitsulo.
Sangalalani ndi mwayi wofikira kukope la digito la The Additive Report kuti mudziwe momwe zopangira zowonjezera zingagwiritsire ntchito kupititsa patsogolo magwiridwe antchito ndikuwonjezera phindu.
Tsopano ndi mwayi wofikira ku mtundu wa digito wa The Fabricator en Español, mwayi wosavuta kuzinthu zamakampani zamtengo wapatali.