Indlela yoVavanyo lweMishini yezihlangu zeBrake zeCast Iron ezisetyenziswa kwiRolling Stock (Ukukhethwa kwezihlangu zeBrake zoBulukhuni)

Ukukhethwa kwezixhobo zovavanyo loomatshini kwizihlangu zebrake zesinyithi eziphothiweyo kufuneka kuhambelane nomgangatho: ICS 45.060.20. Lo mgangatho ucacisa ukuba uvavanyo lweempawu zoomatshini lwahlulwe lwangamacandelo amabini:

1. Uvavanyo lokuThatha

Kuya kwenziwa ngokuhambelana nemigaqo ye-ISO 6892-1:2019. Ubukhulu kunye nomgangatho wokucubungula iisampuli ezixineneyo kuya kuhlangabezana neemfuno ze-ISO 185:2005.

2. Indlela yoVavanyo loBulukhuni

Iza kusetyenziswa ngokuhambelana ne-ISO 6506-1:2014. Iisampuli zokuqina kufuneka zisikwe kwisiqingatha esisezantsi sebha yovavanyo edityanisiweyo; ukuba akukho bha yovavanyo, kufuneka kuthathwe isihlangu esinye sebhuleki, i-6mm ukuya kwi-10mm ibekwe ecaleni layo, kwaye ubunzima buya kulinganiswa kwiindawo zovavanyo ezi-4, ixabiso eliphakathi libe sisiphumo sovavanyo.

Isiseko seNdlela yoVavanyo loBulukhuni

I-ISO 6506-1:2014 esemgangathweni ethi “Metallic Materials – Brinell Hardness Test – Part 1: Test Method” ichaza umgaqo, iimpawu kunye neenkcazo, izixhobo zovavanyo, iisampulu, iinkqubo zovavanyo, ukungaqiniseki kweziphumo kunye nengxelo yovavanyo lovavanyo lobunzima beBrinell kwizinto zesinyithi.

2.1 Ukukhethwa kwezixhobo zovavanyo: Isivavanyeli soBulukhuni beBrinell (Esicetyiswayo Kuqala)

Iingenelo: Indawo yokugquma inkulu, enokubonakalisa ubulukhuni bezinto zesinyithi (isinyithi esixonxiweyo sinokuba nesakhiwo esingalinganiyo), kwaye iziphumo zibonakala ngakumbi.

Ifanelekile kwi-cast iron enobunzima obuphakathi nobuphantsi (HB 80 – 450), egubungela ngokupheleleyo uluhlu lobunzima bezihlangu ze-cast iron.

Lo msebenzi ulula kakhulu, kwaye imfuneko yokugqitywa komphezulu wesampuli iphantsi kakhulu (ngokubanzi iRa 1.6 - 6.3μm yanele).

2.2 Umgaqo woVavanyo loBulukhuni bukaBrinell

Lo mgaqo ungashwankathelwa ngolu hlobo lulandelayo: Ibhola elukhuni ye-alloy (okanye ibhola yentsimbi ecinyiweyo) enobubanzi obuyi-10mm icinezelwa kumphezulu wesampuli phantsi kwamandla athile ovavanyo (afana ne-3000kgf). Emva kokulinganisa ububanzi bokutsalwa, ixabiso lobunzima (HBW) libalwa ukuze lichaze amandla ezinto zokumelana nokuguqulwa kweplastiki. Inzuzo yayo ephambili ikukubonakaliswa okunamandla kweziphumo, okunokubonakalisa iimpawu zobunzima obukhulu bezinto zokwenziwa. Yindlela eqhelekileyo esetyenziswa kakhulu kuvavanyo lokusebenza kwezinto zesinyithi.

2.3 Iimpawu kunye neenkcazo zeBrinell Hardness Value

Inkcazo engundoqo yexabiso lobunzima beBrinell (HBW) yile: umlinganiselo wamandla ovavanyo (F) kwindawo yomphezulu we-indentation (A), kunye neyunithi ye-MPa (kodwa iyunithi ayiphawulwanga, kwaye kusetyenziswa ixabiso lenani kuphela). Ifomula yokubala yile ilandelayo:HBW=πD(D−D2−d2​)2×0.102×F
Apho:

U-F ngamandla ovavanyo (iyunithi: N);

U-D bububanzi be-indenter (iyunithi: mm);

u-d ngumlinganiselo ophakathi wobubanzi bokutsalwa (iyunithi: mm);

I-coefficient “0.102″ yinto yokuguqula esetyenziselwa ukuguqula iyunithi yamandla ovavanyo ukusuka kwi-kgf ukuya kwi-N (ukuba ibalwe ngqo kwi-N, ifomula ingenziwa lula).

Kuyabonakala kwifomula yokuba phantsi kwamandla ovavanyo afanayo kunye nobubanzi be-indenter, okukhona ububanzi be-indenter buncinci, kokukhona amandla ezinto zokumelana nokuguqulwa kweplastiki abe namandla ngakumbi, kwaye kokukhona ixabiso lobunzima beBrinell liphezulu; ngokuchaseneyo, ixabiso lobunzima liphantsi.

Ngokweempawu zezinto ezibonakalayo zezihlangu ze-cast iron brake (i-grey cast iron), iiparameter zovavanyo lobunzima beBrinell zihlala zilandelayo:

Amandla ovavanyo (F): Ngokubanzi, kusetyenziswa i-3000kgf (29.42kN), kwaye uphawu lobunzima oluhambelanayo yi-“HBW 10/3000″.

Qaphela: Ukuba isampuli incinci okanye izinto zithambile, amandla ovavanyo anokulungiswa (afana ne-1500kgf okanye i-500kgf) ngokuhambelana ne-ISO 6506-1:2014, kodwa oku kuya kuboniswa kwingxelo yovavanyo.