Ukutyalwa koTyalo-mali kuMacandelo eMibhobho yoShishino: Ngaba iyiXabiso

Ngokusetyenziswa kwezixhobo zokusika zesayensi kunye neendlela ezihlonitshwa lixesha, utyalo-mali yinkqubo enzima yokuvelisa evelisa ngokuthe ngqo kwaye entsonkothileyo. amacandelo emibhobho yoshishino. Usebenzisa le ndlela ichanekileyo yokuphosa, wenza iimodeli zewax ezineenkcukacha, uzigqume ngamaqokobhe odongwe, emva koko ugalele isinyithi esinyibilikisiweyo phezu kwawo ukwenza iindawo ezichaneke kakhulu ngobukhulu kwaye zinemiphetho emikhulu. Ukukwazi ukwenza iijiyometri ezintsonkothileyo, ukufezekisa ukunyamezelana okuqinileyo, kunye nokusebenza ngezinto ezahlukeneyo, ukusuka kwiintsimbi zekhabhoni eziqhelekileyo ukuya kwii-superalloys ezinqabileyo, zimbalwa zeenzuzo ezinikezelwa yi-investment casting kubavelisi abajonga iindlela zokuvelisa kwiinqununu ezibalulekileyo zemibhobho yezoshishino. Le nkqubo isusa umsebenzi omninzi ekufuneka wenziwe ngesandla, kwaye iindawo eziphuma kuyo zihlangabezana nemigangatho engqongqo yoshishino yokugcina uxinzelelo, ukuxhathisa umhlwa, kunye nokuba nesakhiwo esiphilileyo. Xa uyazi izinto ezilungileyo, ezimbi, kunye nemiba yezoqoqosho yokuphosa utyalo-mali, unokwenza ukhetho olufanelekileyo kwiiprojekthi ezifuna ukufakwa kombhobho okumgangatho ophezulu kunye nezinye iindawo ezikhethekileyo.

Izinto eziluncedo kwezobuGcisa zokuSasa uTyalo-mali

Ukuchaneka okuPhakamileyo koMda kunye noMgangatho woMphezulu

Amaxesha amaninzi, ukuphosa utyalo-mali kunokufikelela ukunyamezela kwe-±0.005 intshi kwimilinganiselo ebalulekileyo ngaphandle kwesidingo sokusika okongeziweyo. Oku kuthetha ukuba amacandelo emibhobho yoshishino ingaba nemilinganiselo echanekileyo kakhulu. Oku kuchanekile kuba inkqubo inokukopa iinkcukacha ezincinci kushicilelo lwewax yoqobo. Oku kuyivumela ukuba yenze iinxalenye ezineepaseji ezigudileyo zangaphakathi kunye neemilo ezintsonkothileyo zangaphandle ezinokuba nzima okanye akunakwenzeka ukwenza ngeendlela eziqhelekileyo zomatshini. Ubuchwephesha bokubumba iqokobhe leceramic lwenza ugqibo olungcono lomphezulu, ngoko ke ixesha elininzi kunye namanyathelo okusila kunye nokupholisha ayimfuneko kwiindlela eziqhelekileyo zokuvelisa. Imiphezulu egudileyo njenge-cast yezixhobo zemibhobho yemizi-mveliso eneempawu zokuhamba ezichanekileyo, njengemizimba yevalvu kunye nezindlu zempompo, uxinzelelo oluphantsi lwehla kunye nokugcina ingxolo incinci, enokuchaphazela indlela esebenza kakuhle ngayo inkqubo. Ukwenziwa kotyalo-mali kuqinisekisa ukuba ukunyamezelana okufanelekileyo kuhlala kuyafana kuyo yonke imveliso. Oku kwenza indibano ithembeke ngakumbi kwaye inciphisa umngcipheko weengxaki zokufakela kwiinkqubo ezibalulekileyo zemibhobho.

Ubunakho beJiyometri entsonkothileyo

Ukusebenzisa indlela yokuphosa utyalo-mali yeyona ndlela ilungileyo yokwenza iinxalenye zemibhobho yoshishino enemingxuma yangaphakathi entsonkothileyo, ii-undercuts, kunye neemilo ezinokwakheka kuka-three-dimensional eziya kufuneka zenziwe kumaqhekeza amaninzi omatshini okanye i-welding eninzi. Imijelo yokupholisa yangaphakathi, iitanki zokuhambisa ukuhamba, kunye neempawu zokulungisa ezakhelwe ngaphakathi zenza kube lula ukuphosa iinxalenye ngokuthe ngqo. Awunyanzelekanga ukuba wakhe amanyathelo okanye iindlela ezivuzayo ezinokubakho, ezinokwenza inkqubo ingathembeki kangako. Olu phawu luluncedo kakhulu kwimigca yokuhamba entsonkothileyo eyimfuneko ekusebenzeni okuphezulu kumacandelo emibhobho yoshishino ekhethekileyo njengezindlu zeiturbine, iiheader zokutshintsha ubushushu, kunye nemizimba yevalvu yesiko. Ukusika kwendabuko akukwazi ukuphatha imigca ewelayo, iindonga ezinobubanzi obuhlukeneyo, okanye iikona zangaphakathi ezibukhali. Lo matshini unako. Ngelixa usahlangabezana neemfuno zokusetyenziswa koxinzelelo oluphezulu, utyalo-mali lukwavumela ukuba wenze iindawo ezingenanto ezinobunzima obuqhelekileyo bodonga.

Ukuguquguquka kwezinto kunye neePropati zeMetallurgical

Ikhabhoni eqhelekileyo kunye neentsimbi ezingenasici, kunye neentsimbi ezikhethekileyo ezenzelwe iimeko ezinzima, zonke zingasetyenziswa kwiindlela zokuphosa utyalo-mali ukwenza. amacandelo emibhobho yoshishino. Xa kuthelekiswa neengxenye ezenziwe kunye nezinye iindlela zokuphosa, ukuchithwa kotyalo-mali kudala izakhiwo zetsimbi ezingcono kunye neenkozo ezincinci kunye nokwahlula okuncinci ngenxa yokuba indawo yokuqinisa ilawulwa. Izixhobo zemibhobho yemizi-mveliso yemisebenzi enzima kushicilelo lwemichiza, ukuveliswa kombane, kunye nemizi-mveliso yeenqwelo-moya zinokwenziwa kusetyenziswa ii-superalloys, iialloyi ze-titanium, kunye nemathiriyeli ekhethekileyo ekwaziyo ukumelana nomhlwa ezinokusetyenzwa ngempumelelo. Ngokulawula ngokuchanekileyo i-alloy makeup kunye namanyathelo okunyanga ubushushu, indlela iqinisekisa ukuba iindawo ezigqityiweyo zihlangabezana nemigangatho ethile yepropathi yomatshini yokuqina, i-ductility, kunye nokuxhathisa ukubola. Umzekelo, ukuphosa utyalo-mali kwenza kube lula ukwenza iinxalenye ezineempawu zemathiriyeli ezahlukeneyo ngaphakathi kwendawo enye, njengezixhobo eziphambili kunye neendawo ezinganxiliyo.

Uhlalutyo lwexabiso lokuSebenza

Iingqwalasela zoTyalo-mali lokuqala kunye neZixhobo

Ukuphila koqoqosho lotyalo-mali kumacandelo emibhobho yoshishino kuxhomekeke kakhulu kumthamo wemveliso kunye nokuntsonkotha kwecandelo, kunye neendleko zokuqala zezixhobo ezimele utyalo-mali lwangaphambili olubalulekileyo ekufuneka luhlawulwe kulo lonke uhambo lwemveliso. Ipatheni yesixhobo sotyalo-mali ngokuqhelekileyo ifuna ukuchaneka kwe-machining okanye ukuveliswa okongeziweyo kweepateni eziphambili, kulandelwa kuphuhliso lwezixhobo zokubumba iinaliti zokuvelisa ipateni ye-wax. Ngelixa ezi ndleko zokuqala zinokuba nkulu, ngakumbi kwiijiyometri ezintsonkothileyo, izixhobo zihlala zibonelela ngobomi benkonzo obulinganiswa kumawaka emijikelo ngokulungiswa okufanelekileyo kunye nokhathalelo. Kumacandelo emibhobho yoshishino enomthamo wemveliso odlula amakhulu aliqela amaqhekeza, ixabiso lesixhobo seyunithi nganye liya lithandeka ngakumbi xa lithelekiswa noomatshini bokwenza obunye. Ubume bemodyuli besixhobo sokubeka utyalo-mali kwakhona kwenza uhlengahlengiso loyilo kunye nokwahluka kobukhulu phakathi kweentsapho zemveliso, ukusasaza iindleko zophuhliso kwiiyantlukwano ezininzi zamacandelo kunye nokwandisa ubomi boqoqosho botyalo-mali lwezixhobo zokuqala.

Ubuchule beMveliso kunye neeMfuno zoMsebenzi

Imisebenzi yotyalo-mali yotyalo-mali kumacandelo emibhobho yemizi-mveliso idla ngokufuna abasebenzi abanezakhono ezingaphantsi xa kuthelekiswa nomsebenzi womatshini ochanekileyo, njengoko uninzi lokuchaneka komlinganiselo wakhelwe kwisixhobo kunye nenkqubo yeeparamitha kunokuxhomekeka kwisakhono namava omsebenzisi. Ubume obuzenzekelayo bezibonelelo zokuphosa utyalo-mali zanamhlanje zenza ukuba amazinga emveliso angaguquki kunye nongenelelo oluncinci lwabaqhubi, ukunciphisa iindleko zabasebenzi kunye nokuphucula ukuqikelelwa kweeshedyuli zokuhanjiswa. Amaxesha omjikelo wotyalo-mali adla ngokude kunemisebenzi elula yomatshini, kodwa ukupheliswa kokusetwa okuninzi kunye notshintsho lwesixhobo kudla ngokukhokelela ekuthelekiseni okanye ukodlula konke okuphumayo kumacandelo antsonkothileyo. Ukukwazi ukuphosa amacandelo amaninzi ngaxeshanye kwisibumba esinye siphucula ngakumbi ukusebenza kakuhle kwemveliso, ngakumbi kumacandelo amancinci emibhobho yoshishino enokuthi icwangciswe ngokucwangciswa kweqela. Iinkqubo zolawulo lomgangatho kumaziko otyalo-mali zijolise ekubekweni kweliso kwinkqubo kunye nohlalutyo lweenkcukacha-manani endaweni yokuhlolwa kwenxalenye yomntu ngamnye, ukunciphisa umsebenzi wokuhlola ngelixa kugcinwa amanqanaba angaguqukiyo omgangatho.

Ukuqwalaselwa kweendleko zoBomi

Utyalo mali amacandelo emibhobho yoshishino zihlala zineendleko eziphantsi zobomi kuba zithembeke ngakumbi kwaye zihlala ixesha elide kunokhetho olwenziwe ngezinye iindlela. Oku kungenxa yomgangatho wabo we-metallurgical ongcono kunye nokuchaneka komda. Kuba utyalo-mali lungenazo iincopho zoxinzelelo lomatshini, kwaye i-microstructure yabo ihlala ilungile, banokhuseleko olungcono lokunxiba kunye nokusebenza komhlwa kwiisetingi zenkonzo eqatha. Ukulungiswa okumbalwa kunye nezithuba ezinde zenkonzo kunceda ukwenza iindleko eziphezulu zecandelo lokuqala, ngakumbi kwiimeko apho ixesha lokuphumla libiza imali eninzi. Ngokudibanisa imisebenzi emininzi ibe yinxalenye enye, inkqubo yokuhlanganisa yenziwa lula kwaye azikho iindawo zokungaphumeleli ezinokubakho kumalungu kunye nezibophelelo, eziphucula ngakumbi ukuthembeka kwenkqubo. Iimpawu zokwenziwa komsebenzi eziphuculweyo zotyalo-mali kumacandelo emibhobho yoshishino kwizicelo ezibalulekileyo zihlala zixhasa ixabiso leprimiyamu ngexabiso eliphantsi lilonke lobunini kubomi benkonzo yecandelo.

ImiGangatho yoMgangatho kunye nezicelo zoShishino

Izatifikethi kunye neeMfuno zoVavanyo

Amacandelo ombhobho wotyalo-mali kufuneka ahambelane nemigangatho engqongqo yomgangatho kunye neemfuneko zesatifikethi ezohluka ngokuxhomekeke kwizicelo ezijoliswe kuzo kunye nokusingqongileyo kwenkonzo. Izicelo ze-aerospace zifuna ukuthotyelwa kweenkqubo zolawulo lomgangatho we-AS9100 kunye namaxwebhu amaninzi okulandelelwa kwezinto, ngelixa iinxalenye zenqanawa yoxinzelelo kufuneka zihlangabezane neemfuno zeCandelo VIII ze-ASME zoyilo, izixhobo kunye neenkqubo zokuvavanya. Inkqubo yotyalo-mali yotyalo-mali ixhasa ngokwendalo ezi mfuno zomgangatho ngokukwazi kwayo ukuvelisa izakhiwo zetsimbi kunye neempawu ezichanekileyo ezikhokelela kuvavanyo oluthembekileyo kunye neenkqubo zokuhlola. Iindlela zovavanyo ezingonakalisi ezifana novavanyo lweradiographic, ukuhlolwa kokungena kwamanzi, kunye novavanyo lwe-ultrasonic lusetyenziswa rhoqo kumacandelo emibhobho yotyalo-mali ukuze kuqinisekiswe isandi sangaphakathi kunye nokuthembeka komphezulu. Iisistim zolawulo lwenkqubo yobalo-manani zibeka iliso kwiiparamitha ezibalulekileyo kuyo yonke inkqubo yokuphosa, ivumela ukubonwa kwangaphambili kweeyantlukwano ezinokuchaphazela umgangatho wecandelo kunye nokuqinisekisa ukusebenza okungaguqukiyo kuyo yonke imveliso eqhutywayo.

Izicelo eziZodwa kunye neeMfuno zokuSebenza

Kumacandelo ombhobho wemizi-mveliso asetyenziswa kwizicwangciso ezinzima apho ukusebenza kwezinto kunye nokuzinza komzimba kubalulekile ekusebenzeni okukhuselekileyo, ukuchithwa kotyalo-mali kubaluleke kakhulu. Ukusetyenziswa kobushushu obuphezulu ekusetyenzweni kwepetroleum kunye nokuveliswa kombane, iinxalenye kufuneka zikwazi ukugcina iimpawu zazo zoomatshini kunye nemilinganiselo nokuba zifudunyezwe kwaye zipholisiwe amaxesha amaninzi, nto leyo enokuthi igqwethe iinketho ezidityanisiweyo okanye ezenziwe ngoomatshini. Kwiindawo apho iintsimbi zinokugqwala khona, udinga iialloyi ezikhethekileyo kunye nonyango lwangaphezulu. Ukwenziwa kotyalo-mali yindlela engcono yokwenza ezi zinto kunezinye iindlela. Ukusetyenziswa kwe-aerospace kunye nolwandle, apho ukunciphisa ubunzima kubaluleke kakhulu ekusebenzeni kwenkqubo epheleleyo, indlela ingasetyenziselwa ukwenza iinqununu zemibhobho ye-industrial lightweight. Ukukwazi ukwenza utyalo-mali ukwenza iimilo ezintsonkothileyo zangaphakathi zibaluleke kakhulu kumalungu afuna ukuba nezona mpawu zihamba kakuhle, njengemilomo yeiturbine kunye nobuninzi bokutshintsha ubushushu, apho ukwehla koxinzelelo kunye nokusebenza kobushushu kunefuthe elithe ngqo kwindlela esebenza kakuhle ngayo inkqubo.

Ulawulo loMgangatho kunye neeProtokholi zokuHlola

Kukho izicwangciso zolawulo olupheleleyo lotyalo-mali amacandelo emibhobho yoshishino ezigubungela inyathelo ngalinye lenkqubo yokuvelisa, ukusuka ekujongeni izinto ezifikayo ukuya kuvavanyo lokugqibela kunye nohlolo. Ngomgangatho ongaguqukiyo kunye nokufunyanwa kwangaphambili kweenguqu zenkqubo, izibonelelo zokuphosa utyalo-mali zangoku zisebenzisa iinkqubo zokulandela umkhondo eziqhubela phambili ezigcina iliso kwiiprofayili zobushushu, amazinga okugalela, kunye neepateni zokuqinisa. Ukuhlolwa kwemilinganiselo usebenzisa izixhobo zokulinganisa ukulungelelanisa kunye neenkqubo zokuskena okubonakalayo kuqinisekisa ukuba iindawo eziphosiweyo zingaphakathi kokunyamezela okufunekayo ngaphandle kokufuna ukubamba okanye ukuseta ixesha elininzi. Ukuqinisekiswa kwepropathi yoomatshini, uhlalutyo lwe-microstructure, kunye nobungqina bokwenziwa kweekhemikhali zizo zonke iinxalenye zeenkqubo zokuvavanya i-metallurgical eziqinisekisa ukuba iinxalenye ezigqityiweyo ziyahlangabezana nazo zonke iimfuno zemisebenzi ekumele ukuba yenziwe. Iinkqubo zokulandelelwa kwamaxwebhu zivumela iimpendulo ezikhawulezayo kwimiba esemgangathweni kunye nenkxaso yoqinisekiso lweemfuno zosetyenziso olubalulekileyo kumashishini alawulwayo.

isiphelo

Ukwenziwa kotyalo-mali kuvela njengendlela yokwenziwa kwezixhobo zemibhobho yemizi-mveliso, ngakumbi xa iijiyometri ezintsonkothileyo, iipropathi zemathiriyeli eziphezulu, kunye nokunyamezelana zizinto eziyimfuneko. Inkqubo inikezela ngexabiso elibalulekileyo ngokunciphisa iindleko zoomatshini, iimpawu zokusebenza eziphuculweyo, kunye nokukwazi ukuvelisa amacandelo anokuthi angenzeki okanye abize kakhulu kusetyenziswa iindlela ezizezinye zokuvelisa. Ukuzinikela kwe-RAYOUNG kumgangatho kunye nokutsha njengomthengisi wecandelo lombhobho woshishino ulungelelanisa ngokugqibeleleyo nokuchaneka kunye nokuthembeka okubonelela ngotyalo-mali kwizicelo ezibalulekileyo zombhobho.

FAQ

1. Yeyiphi imiqulu yemveliso eyenza ukuba utyalo-mali lusebenze kuqoqosho?

Utyalo-mali luba neendleko ezisebenzayo kumacandelo emibhobho yeshishini ngokuqhelekileyo kwimiqulu yemveliso engaphezu kwama-100-200 amaqhekeza, kuxhomekeke kubunzima becandelo kunye nobukhulu. Iindleko eziphezulu zokuqala zokusebenzisa izixhobo zilungiswa ngokunciphisa iindleko zokwenziwa kweyunithi nganye kunye nokupheliswa kwemisebenzi yesibini yomatshini. Kumacandelo antsokothileyo kakhulu afuna ukwenziwa ngoomatshini okubanzi, ukufakwa kotyalo-mali kunoqoqosho nakwimithamo ephantsi.

2. Unjani umgangatho wokuphoswa kotyalo-mali xa uthelekisa kumacandelo oomatshini?

Amacandelo emibhobho yotyalo-mali ephoswe kwimizi-mveliso ahlala ebonisa iipropati eziphezulu zesinyithi ngenxa yokuqina okulawulwayo kunye nezakhiwo eziziinkozo ezintle. Inkqubo iphelisa ukugxininiswa koxinzelelo ngomatshini ngelixa ibonelela ngokugqitywa komphezulu ongcono kunye nokuhambelana komda. Nangona kunjalo, ezinye ii-aplikeshini zisenokufuna umatshini olinganiselweyo wokutywina okubalulekileyo okanye uqhagamshelo oludityanisiweyo ukuze kuphunyezwe ukusebenza kakuhle.

3. Ziziphi izinto ezifanelekileyo zokutshala utyalo-mali lwamacandelo ombhobho?

Utyalo-mali luthatha zonke iialloyi zobunjineli ezisetyenziswa kumacandelo emibhobho yoshishino, kubandakanywa iintsimbi zekhabhoni, iintsimbi ezingatyiwayo, iialloyi eziphindwe kabini, ii-superalloys ezisekwe kwinickel, kunye neealloyi zetitanium. Ukukhethwa kwezinto kuxhomekeke kwiimfuno zenkonzo ezifana nobushushu, uxinzelelo, kunye nemekobume eyonakalisayo. Inkqubo ihlala ivumela ukusetyenziswa kwe-alloys ephezulu yokusebenza kuya kuba nzima ukumatshini ngoqoqosho.

4. Ngawaphi amaxesha okukhokela ekufuneka alindelwe kumacandelo otyalo-mali?

Amaxesha okukhokela aqhelekileyo kutyalo-mali oluphoswe kumashishini ombhobho aqala kwiiveki ezi-8-16 ngokuxhomekeke kubunzima, iimfuno zezinto eziphathekayo, kunye nomthamo wemveliso. Uphuhliso lwezixhobo zokuqala longeza iiveki ezi-4-8 kunikezelo lwamanqaku okuqala. Nangona kunjalo, ukukwazi ukuphosa iimilo ezintsonkothileyo ngaphandle kwemisebenzi yesibini kaninzi kukhokelela kumaxesha amafutshane okuhanjiswa xa kuthelekiswa noomatshini abahlukeneyo abafuna imisebenzi yokuseta ezininzi.

I-HEBEI RAYOUNG PIPELINE: I-Premium Industrial Pipe Components Manufacturers

Thina e-HEBEI RAYOUNG PIPELINE TECHNOLOGY CO., LTD. uyazi ukuba ukwenza i-top-notch amacandelo emibhobho yoshishino, udinga indibaniselwano yolwazi lwethu lokuvelisa kunye nokuzinikela kwethu okungapheliyo kumgangatho. Iingqiniba zethu zentsimbi, ii-reducers, kunye neeflange ziyinto yesibini nanye ngenxa yokuba singabenzi bombhobho abaziwayo behlabathi kunye nezifakelo nangenxa yokuba sidibanisa ubugcisa behlabathi lakudala kunye neteknoloji yokuvelisa. Ukuzibophelela kwethu kumgangatho othe gqolo kuboniswa yi-ISO 9001:2015 yethu yolwamkelo. Ukongezelela, iziqinisekiso zethu ze-GOST-R kunye ne-SGS zibonakalisa ukuzinikela kwethu kwimigangatho yamazwe ngamazwe. Kungakhathaliseki ukuba iprojekthi yakho ifuna ulungelelwaniso oluqhelekileyo okanye amacandelo epayipi yoshishino eyenziwe ngobunjineli ukwenzela ukusetyenziswa okuthe ngqo, iqela lethu leengcali linolwazi kunye namandla okwenza ukuba kwenzeke. Bhrawuza ukhetho lwethu olubanzi lofakelo lweprimiyamu yombhobho ukuze ufumane ezona zifanelekileyo kwiprojekthi yakho elandelayo. Qhagamshelana nathi namhlanje ku info@hb-steel.com ukuxoxa ngeemfuno zakho ezithile kwaye ufumane inzuzo ye-RAYOUNG kumacandelo emibhobho yoshishino.

Ucaphulo

1. UCampbell, J. "Incwadi eGqibeleleyo yokuCasa: IiNkqubo zokuCasa iMetal, ubuChwepheshe kunye noYilo." Uhlelo lwesi-2, eGcuwa-Heinemann, ngo-2015.

2. UJones, S. kunye noJolly, MR "Ubuchule beNkqubo yokuTyalwa kweTyalo-mali kwiCandelo lobuNjineli obuchanekileyo." Iinkqubo zeZiko leeNjineli zobuNjineli, iCandelo B: Ijenali yoMveliso wobuNjineli, vol. 235, no. 4, 2021, iphepha 589-604.

3. U-Singh, u-RP no-Kumar, A. "UVavanyo loMgangatho woTyalo-mali lwe-Cast Industrial Components: Uphononongo oluBanzi." Izinto zeMathiriyeli kunye neeNkqubo zokuVelisa, vol. 38, hayi. 2, 2023, iphepha 187-201.

4. Thompson, KL, et al. "Uhlahlelo lwezoQoqosho loTyalo-mali oluNxibelelana neNdlela ezizezinye zokuVelisa kwiiJometri eziNxibelele." Ijenali yeHlabathi yoQoqosho lweMveliso, vol. 245, 2022, iphepha 108-125.

5. UWilliams, u-DM kunye noZhang, H. "Izinto eziphathekayo kunye nokuSebenza koTyalo-mali lwe-Cast High-Temperature Alloys." Ijenali yeTekhnoloji yoLungiso lweMathiriyeli, vol. 312, 2023, iphepha 117-134.

6. URodriguez, CA "I-Technology Casting Technology: Izicelo zanamhlanje kwi-Industrial Manufacturing." Ubunjineli bokuCasa kunye neTekhnoloji, vol. 67, hayi. 3, 2023, iphepha 45-58.