Iiprotokholi zovavanyo ezahlukeneyo (uBrinell, uRockwell, uVickers) zineenkqubo ezithile zeprojekthi evavanywayo. Uvavanyo lweRockwell T lufanelekile ekuhloleni iityhubhu zodonga olukhanyayo ngokusika ityhubhu ngobude kunye nokuvavanya udonga ukusuka kububanzi bangaphakathi kunobubanzi bangaphandle.
Uku-odola ityhubhu kufana nokuya kwindawo yokuthengisa iimoto uze u-odole imoto okanye ilori. Namhlanje, iindlela ezininzi ezikhoyo zivumela abathengi ukuba benze ngokwezifiso imoto ngeendlela ezahlukeneyo - imibala yangaphakathi neyangaphandle, iipakethe zokuhlobisa zangaphakathi, iindlela zokulungisa ngaphandle, ukhetho lwe-powertrain, kunye nenkqubo yesandi ephantse ilingane nenkqubo yokuzonwabisa yasekhaya. Ngenxa yazo zonke ezi ndlela, usenokungoneliseki yimoto eqhelekileyo, engenamsebenzi.
Iipayipi zentsimbi zinjalo kanye. Zineenketho ezininzi okanye iinkcukacha. Ukongeza kwiimilinganiselo, iinkcukacha zidwelisa iipropati zeekhemikhali kunye neenkampani ezininzi ezifana namandla amancinci okuvelisa (MYS), amandla okuqina aphezulu (UTS), kunye nokwandiswa okuncinci ngaphambi kokuba kufe. Nangona kunjalo, uninzi kushishino—iinjineli, iiarhente zokuthenga, kunye nabavelisi—zisebenzisa iindlela ezimfutshane zoshishino ezifuna ukusetyenziswa kombhobho “oqhelekileyo” odibeneyo kwaye zichaza uphawu olunye kuphela: ubulukhuni.
Zama uku-odola imoto ngophawu olunye (“Ndifuna imoto enothumelo oluzenzekelayo”) kwaye awuyi kufikelela kakhulu kumthengisi. Kufuneka agcwalise ifomu yoku-odola eneendlela ezininzi. Ipayipi yiloo nto kanye – ukuze afumane ipayipi efanelekileyo yesicelo, umenzi wepayipi udinga ulwazi olungaphezulu kunobunzima nje kuphela.
Ukuqina kuba njani indawo eyaziwayo kwezinye iimpawu zoomatshini? Mhlawumbi kwaqala ngomvelisi wepayipi. Ngenxa yokuba uvavanyo lokuqina lukhawuleza, lulula, kwaye lufuna izixhobo ezingabizi kakhulu, abathengisi beetyhubhu badla ngokusebenzisa uvavanyo lokuqina ukuthelekisa iityhubhu ezimbini. Ukuze benze uvavanyo lokuqina, konke abakudingayo bubude obugudileyo bepayipi kunye nesitendi sovavanyo.
Ukuqina kwetyhubhu kuhambelana kakuhle ne-UTS, kwaye ngokomthetho, iipesenti okanye uluhlu lweepesenti luluncedo ekuqikeleleni i-MYS, ngoko ke kulula ukubona indlela uvavanyo lokuqina olunokuba yi-proxy efanelekileyo kwezinye iimpawu.
Kwakhona, ezinye iimvavanyo zinzima kakhulu. Nangona uvavanyo lobunzima luthatha umzuzu omnye okanye ngaphezulu kumatshini omnye, uvavanyo lwe-MYS, i-UTS kunye nolwandiso lufuna ukulungiswa kwesampulu kunye notyalo-mali olukhulu kwizixhobo zelebhu ezinkulu. Ukuthelekisa, kuthatha imizuzwana embalwa ukuba umqhubi we-tube mill enze uvavanyo lobunzima kunye neeyure kwingcali ye-metallurgical ukwenza uvavanyo lokutsalwa. Akunzima ukwenza uvavanyo lobunzima.
Oku akuthethi ukuba abavelisi beepayipi abachwepheshayo abasebenzisi uvavanyo lobunzima. Kukhuselekile ukuthi uninzi lwabantu luyakwenza oko, kodwa ngenxa yokuba benza uvavanyo lokuphindaphinda kunye nokuphindaphinda kuzo zonke izixhobo zabo zovavanyo, bayazi kakuhle imida yovavanyo. Uninzi lusebenzisa uvavanyo lobunzima beetyhubhu njengenxalenye yenkqubo yokuvelisa, kodwa abalisebenzisi ukulinganisa iimpawu zeetyhubhu. Olu luvavanyo lokupasa/lokungaphumeleli nje.
Kutheni kufuneka wazi nge-MYS, i-UTS kunye nobude obuncinci? Zibonisa indlela ityhubhu eza kusebenza ngayo xa ihlanganiswa.
I-MYS yeyona nto incinci ebangela ukuguquka okungapheliyo kwezinto. Ukuba uzama ukugoba ucingo oluthe tye (njenge-hanger yejazi) kancinci uze ukhulule uxinzelelo, enye yezinto ezimbini iya kwenzeka: iya kubuyela kwimeko yayo yokuqala (ithe tye) okanye iya kuhlala igobile. Ukuba isathe tye, awukadluli kwi-MYS. Ukuba isagobile, uyigqithisile.
Ngoku, sebenzisa iipliers ukubopha omabini amacala entambo. Ukuba ungayikrazula intambo ibe ziingceba ezimbini, ungaphezulu kwe-UTS yayo. Ubeka uxinzelelo olukhulu kuyo kwaye uneengcingo ezimbini zokubonisa umzamo wakho ongaphezu kwamandla omntu. Ukuba ubude bokuqala bentambo buyi-intshi ezi-5, kwaye ubude obubini emva kokusilela budibanisa ukuya kwi-intshi ezi-6, intambo yolulwa nge-intshi e-1, okanye i-20%. Uvavanyo lokwenyani lobude lulinganiswa ngaphakathi kwe-intshi ezi-2 ukusuka kwindawo yokusilela, kodwa nantoni na - ingcamango yentambo yokutsala ibonisa i-UTS.
Iisampulu ze-photomicrograph zentsimbi kufuneka zisikwe, zicolwe, kwaye zikrolwe kusetyenziswa isisombululo esincinci se-asidi (ngesiqhelo i-nitric acid kunye notywala (i-nitroethanol)) ukuze kubonakale iinkozo. Ukwandiswa kwe-100x kudla ngokusetyenziswa ukuhlola iinkozo zentsimbi kunye nokuchonga ubungakanani beenkozo.
Ukuqina luvavanyo lwendlela izinto ezisabela ngayo xa zichaphazeleka. Khawucinge ngokufaka umbhobho omfutshane kwi-vise enemihlathi egobileyo uze ujike i-vise ivaleke. Ukongeza ekusitheliseni ityhubhu, imihlathi ye-vise ikwashiya ukuxinana kumphezulu wetyhubhu.
Yindlela olusebenza ngayo uvavanyo lobunzima, kodwa alukho nzima kangako. Olu vavanyo lunobungakanani bempembelelo elawulwayo kunye noxinzelelo olulawulwayo. La mandla aguqula umphezulu, nto leyo eyenza ukugoba okanye ukugoba. Ubungakanani okanye ubunzulu bokugoba bumisela ubunzima besinyithi.
Ukuvavanya intsimbi, uvavanyo lobunzima oluqhelekileyo yiBrinell, Vickers, kunye neRockwell. Ngayinye inesikali sayo, kwaye ezinye zineendlela ezininzi zovavanyo, ezifana neRockwell A, B, kunye neC. Kwimibhobho yentsimbi, i-ASTM Specification A513 ibhekisa kuvavanyo lweRockwell B (olufinyeziweyo njenge-HRB okanye i-RB). Uvavanyo lweRockwell B lulinganisa umahluko ekungeneni kwentsimbi ngebhola yentsimbi enobubanzi obuyi-1⁄16-intshi phakathi komthwalo omncinci wangaphambi kokufakwa kunye nomthwalo oyintloko oyi-100 kgf. Isiphumo esiqhelekileyo sentsimbi ethambileyo eqhelekileyo yi-HRB 60.
Izazinzulu zezinto ziyazi ukuba ubunzima buhambelana ngqo ne-UTS. Ke ngoko, ubunzima obuthile bunokuqikelela i-UTS. Ngokufanayo, abavelisi beetyhubhu bayazi ukuba i-MYS kunye ne-UTS zihlobene. Kwipayipi edibeneyo, i-MYS idla ngokuba yi-70% ukuya kwi-85% ye-UTS. Ubungakanani obuchanekileyo buxhomekeke kwinkqubo yokwenza ityhubhu. Ubunzima be-HRB 60 buhambelana ne-UTS yeepawundi ezingama-60,000 nge-intshi yesikwere (PSI) kunye ne-MYS engama-80%, okanye i-48,000 PSI.
Eyona nkcazelo ixhaphakileyo yepayipi kwimveliso ngokubanzi bubunzima obukhulu. Ukongeza kubungakanani, injineli yayixhalabele ukucacisa umbhobho we-welded electric resistance welded (ERW) ngaphakathi koluhlu olusebenzayo, olunokubangela ubunzima obukhulu obunokuthi bufumaneke kwi-HRB 60 kumzobo wecandelo. Esi sigqibo sodwa sikhokelela kuluhlu lweepropati zokugqibela zoomatshini, kubandakanya ubunzima ngokwabo.
Okokuqala, ubunzima be-HRB 60 abusixeleli okuninzi. Ukufundwa kwe-HRB 60 linani elingenamlinganiselo. Izinto ezivavanywe nge-HRB 59 zithambile kunezinto ezivavanywe nge-HRB 60, kwaye i-HRB 61 inzima kune-HRB 60, kodwa zingaphi? Ayinakulinganiswa njengomthamo (olinganiswa ngee-decibels), i-torque (elinganiswa ngeeponti-feet), isantya (elinganiswa kumgama ohambelana nexesha), okanye i-UTS (elinganiswa ngeeponti nge-intshi yesikwere). Ukufunda i-HRB 60 akusixeleli nto ithile. Le yimpawu yezinto, kodwa ayisiyompawu ebonakalayo. Okwesibini, uvavanyo lobunzima alufanelekanga ukuphinda okanye ukuphinda. Ukuvavanya iindawo ezimbini kwisampuli yovavanyo, nokuba iindawo zovavanyo zisondelelene, kudla ngokubangela umahluko omkhulu kufundo lobunzima. Ukudibanisa le ngxaki luhlobo lovavanyo. Emva kokuba indawo ilinganisiwe, ayinakulinganiswa okwesibini ukuqinisekisa iziphumo. Ukuphinda uvavanyo akunakwenzeka.
Oku akuthethi ukuba uvavanyo lobunzima alunamsebenzi. Enyanisweni, lubonelela ngesikhokelo esihle se-UTS yesixhobo, kwaye luvavanyo olukhawulezayo nolulula ukulwenza. Nangona kunjalo, wonke umntu obandakanyeka ekuchazeni, ekuthengeni nasekuveliseni iityhubhu kufuneka aqonde imida yazo njengepharamitha yovavanyo.
Ngenxa yokuba umbhobho "oqhelekileyo" awuchazwanga kakuhle, xa kufuneka, abavelisi bemibhobho badla ngokuwunciphisa ukuya kwiintlobo ezimbini zemibhobho yentsimbi kunye nemibhobho ezisetyenziswa kakhulu ezichazwe kwi-ASTM A513: 1008 kunye ne-1010. Kwanasemva kokuphelisa zonke ezinye iintlobo zeetyhubhu, amathuba ngokweempawu zoomatshini zezi ntlobo zimbini zeetyhubhu avulekile kakhulu. Enyanisweni, ezi ntlobo zeetyhubhu zinoluhlu olubanzi lweempawu zoomatshini zalo naluphi na uhlobo.
Umzekelo, ityhubhu ichazwa njengethambileyo ukuba i-MYS iphantsi kwaye ubude bayo buphezulu, oko kuthetha ukuba isebenza ngcono xa itsalwa, ijika kwaye isetiwe kunetyhubhu echazwe njengeqinileyo, ene-MYS ephezulu kunye nobude obuphantsi. Oku kufana nomahluko phakathi kwentambo ethambileyo neqinileyo, efana nee-coat hangers kunye nee-drill.
Ukwandiswa ngokwako yenye into enefuthe elikhulu kwizicelo ezibalulekileyo zemibhobho. Iityhubhu ezinobude obuphezulu zinokumelana namandla okuxinana; izinto ezinobude obuphantsi zibuthathaka ngakumbi kwaye ngoko ke zisengozini yokusilela okuyingozi kohlobo lokudinwa. Nangona kunjalo, ukwanda akunxulumananga ngokuthe ngqo ne-UTS, eyona nto iphambili yoomatshini enxulumene ngqo nobunzima.
Kutheni iimpawu zoomatshini zeetyhubhu zahlukile kangaka? Okokuqala, ukwakheka kweekhemikhali kwahlukile. Intsimbi sisisombululo esiqinileyo sesinyithi kunye nekhabhoni kunye nezinye ii-alloys ezibalulekileyo. Ukuze kube lula, siza kujongana neepesenti zekhabhoni kuphela apha. Iiathom zekhabhoni zithatha indawo yezinye zeeathom zesinyithi, zenze isakhiwo sekristale sentsimbi. I-ASTM 1008 yiklasi eyintloko equka konke enomxholo wekhabhoni ukusuka kwi-0% ukuya kwi-0.10%. I-Zero linani elikhethekileyo kakhulu elivelisa iimpawu ezikhethekileyo xa umxholo wekhabhoni kwintsimbi uphantsi kakhulu. I-ASTM 1010 ichaza umxholo wekhabhoni phakathi kwe-0.08% kunye ne-0.13%. Ezi mahluko azibonakali zikhulu, kodwa zikhulu ngokwaneleyo ukwenza umahluko omkhulu kwenye indawo.
Okwesibini, umbhobho wentsimbi unokwenziwa okanye wenziwe uze emva koko ucutshungulwe kwiinkqubo ezisixhenxe ezahlukeneyo zokuvelisa. I-ASTM A513 enxulumene nemveliso yombhobho we-ERW idwelisa iintlobo ezisixhenxe:
Ukuba ukwakheka kweekhemikhali zentsimbi kunye namanyathelo okuvelisa ityhubhu akunampembelelo kubulukhuni bentsimbi, yintoni? Ukuphendula lo mbuzo kuthetha ukuphonononga iinkcukacha. Lo mbuzo ubuza eminye imibuzo emibini: Zeziphi iinkcukacha, kwaye zisondele kangakanani?
Iinkcukacha malunga neenkozo ezenza intsimbi yimpendulo yokuqala. Xa intsimbi yenziwe kwindawo yokuqala yokugaya intsimbi, ayipholi ibe yibhloko enkulu enesici esinye. Njengoko intsimbi iphola, iimolekyuli zentsimbi zihlela ngokweepateni eziphindaphindayo (iikristale), ngendlela efana nendlela iikhephu ezibumba ngayo. Emva kokuba iikristale zenziwe, zihlangana zibe ngamaqela abizwa ngokuba ziinkozo. Njengoko ukupholisa kuqhubeka, iinkozo ziyakhula kwaye zakheke kulo lonke iphepha okanye ipleyiti. Iinkozo ziyayeka ukukhula njengoko iimolekyuli zentsimbi zokugqibela zifunxwa ziinkozo. Konke oku kwenzeka kwinqanaba le-microscopic kuba ubungakanani obuqhelekileyo beenkozo zentsimbi bumalunga ne-64 µ okanye i-0.0025 intshi ububanzi. Nangona inkozo nganye ifana nelandelayo, ayifani. Ziyahluka kancinci ngobukhulu, ukujongwa kunye nomxholo wekhabhoni. Unxibelelwano phakathi kweenkozo lubizwa ngokuba ngumda weenkozo. Xa intsimbi ingaphumeleli, umzekelo ngenxa yokudinwa, idla ngokusilela kwimida yeenkozo.
Umele ujonge kude kangakanani ukuze ubone iinkozo ezibonakalayo? Ukwandiswa okuphindwe kayi-100, okanye umbono womntu ophindwe kayi-100, kwanele. Nangona kunjalo, ukujonga nje intsimbi enganyangwanga izihlandlo ezili-100 amandla awabonisi nto ingako. Isampulu ilungiswa ngokupolisha isampulu kwaye ikrole umphezulu nge-asidi (ngesiqhelo i-asidi ye-nitric kunye notywala) ebizwa ngokuba yi-nitroethanol etchant.
Ziinkozo kunye nelathisi yazo yangaphakathi ezimisela amandla empembelelo, i-MYS, i-UTS kunye nobude intsimbi enokumelana nabo ngaphambi kokuba yonakale.
Amanyathelo okwenza intsimbi, anjengokuqengqeleka kwentsimbi eshushu nebandayo, afaka uxinzelelo kwisakhiwo sengqolowa; ukuba atshintsha imo ngokusisigxina, oku kuthetha ukuba uxinzelelo luyayitshintsha ingqolowa. Amanye amanyathelo okucubungula, anjengokugquma intsimbi ibe yi-coils, ukuyivula, kunye nokuguqula iinkozo zentsimbi nge-tube mill (ukuze yenze ityhubhu ibe nobukhulu bayo). Ukutsala ityhubhu ebandayo kwi-mandrel kukwabeka uxinzelelo kwizinto, njengoko kunjalo nangamanyathelo okuvelisa anjengokugquma nokugqiba. Utshintsho kwisakhiwo sengqolowa lubizwa ngokuba yi-dislocations.
La manyathelo angentla anciphisa ukuqina kwentsimbi, okukuko ukukwazi kwayo ukumelana noxinzelelo lokutsalwa (ukutsalwa-ukuvulwa). Intsimbi iba buthathaka, nto leyo ethetha ukuba isenokuphuka ukuba uqhubeka usebenza kuyo. Ukwandiswa kwentsimbi yenye yeendawo zokuqina kwentsimbi (ukuqina kwentsimbi yenye). Kubalulekile ukuqonda ukuba ukusilela kudla ngokuvela ngexesha loxinzelelo lokutsalwa, kungekhona uxinezeleko. Intsimbi ayimelani kakhulu noxinzelelo lokutsalwa ngenxa yomthamo wayo ophezulu wobude. Nangona kunjalo, intsimbi itshintsha ngokulula xa ixinezelekile – yi-ductile – nto leyo eyinzuzo.
Ikhonkrithi inamandla aphezulu okuxinwa kodwa inamandla amancinci xa ithelekiswa nekhonkrithi. Ezi mpawu zichasene nezo zentsimbi. Yiyo loo nto ikhonkrithi esetyenziselwa iindlela, izakhiwo kunye neendlela zokuhamba ngeenyawo idla ngokufakelwa i-rebar. Isiphumo iba yimveliso enamandla afana nezinto ezimbini: xa iphantsi koxinzelelo, intsimbi inamandla, kwaye xa iphantsi koxinzelelo, ikhonkrithi.
Ngexesha lokusebenza ngokubandayo, njengoko ukuguguleka kwentsimbi kuncipha, ubulukhuni bayo buyanda. Ngamanye amazwi, iya kuqina. Ngokuxhomekeke kwimeko, oku kunokuba luncedo; nangona kunjalo, kunokuba yingozi kuba ubulukhuni bulinganiswa nokuqhekeka. Oko kukuthi, njengoko intsimbi isiba nzima, iya isiba buthathaka kancinci; ke ngoko, kunokwenzeka ukuba ingasebenzi.
Ngamanye amazwi, inyathelo ngalinye lenkqubo lisebenzisa ezinye zeendlela eziguquguqukayo zombhobho. Kuba nzima ngakumbi njengoko inxalenye isebenza, kwaye ukuba inzima kakhulu ayisebenzi. Ukuqina kukubuthathaka, kwaye umbhobho obuthathaka unokungaphumeleli xa usetyenziswa.
Ngaba umenzi unazo naziphi na iindlela kule meko? Ngamafutshane, ewe. Olo khetho luyatshisa, kwaye nangona lungengomlingo kangako, lusondele kakhulu kumlingo kangangoko unako.
Ngokwendlela eqhelekileyo, ukuqhoboshela kususa zonke iziphumo zoxinzelelo lomzimba kwisinyithi. Le nkqubo ifudumeza isinyithi ukuya kubushushu bokunciphisa uxinzelelo okanye ukuphinda sifumane ubushushu, ngaloo ndlela isusa ukuqhawuka. Ngokuxhomekeke kubushushu obuthile kunye nexesha elisetyenzisiweyo kwinkqubo yokuqhoboshela, inkqubo ngaloo ndlela ibuyisela inxalenye okanye yonke indlela eguquguquka ngayo.
Ukuqhoboshela nokulawula ukupholisa kukhuthaza ukukhula kweenkozo. Oku kuluncedo ukuba injongo kukunciphisa ukuqhekeka kwezinto, kodwa ukukhula kweenkozo okungalawulwayo kunokuyithambisa kakhulu isinyithi, nto leyo eyenze ukuba ingasetyenziswa ngendlela ebekiweyo. Ukumisa inkqubo yokuqhoboshela yenye into ephantse ibe ngumlingo. Ukuqhoboshela kubushushu obufanelekileyo ngesixhobo sokuqhoboshela esifanelekileyo ngexesha elifanelekileyo kwenza inkqubo iyeke ngokukhawuleza ukuze kufumaneke iipropati zokubuyisa intsimbi.
Ngaba kufuneka siyilahle inkcazo yobunzima? Hayi. Iimpawu zobunzima zibaluleke kakhulu njengendawo yokubhekisa xa kucaciswa imibhobho yentsimbi. Umlinganiselo oluncedo, ubunzima yenye yeempawu ezininzi ekufuneka zichazwe xa kuodolwa izinto zetyhubhu kwaye zihlolwe xa zifunyenwe (kwaye kufuneka zirekhodwe kunye nokuthunyelwa ngakunye). Xa ukuhlolwa kobunzima kusemgangathweni wokuhlola, kufuneka kube namaxabiso esikali afanelekileyo kunye noluhlu lolawulo.
Nangona kunjalo, ayilovavanyo lokwenyani lwezinto ezifanelekileyo (ukwamkela okanye ukwala). Ukongeza kubulukhuni, abavelisi kufuneka bavavanye ukuthunyelwa ngamanye amaxesha ukuze babone ezinye iimpawu ezifanelekileyo, ezifana ne-MYS, i-UTS, okanye ubuncinci bokwandiswa, kuxhomekeke ekusetyenzisweni kwetyhubhu.
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.
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