1. Ncaj bevel iav yog qhov yooj yim tshaj plaws bevel iav.Kev ua haujlwm yog yooj yim, tab sis qhov tseeb kis tau tus mob tsis zoo, thiab qhov sib kis tam sim ntawd tsis raug.Nws tsuas yog kis tau raws li kev hloov pauv ntawm kev coj ua, thiab qhov kev xav tau ceev thiab kis tau tus mob tsis nruj., xws li nqa thiab txo qis ntawm lub rooj ua haujlwm ntawm tus nyuj lub taub hau planer, kev ua haujlwm ncej, thiab lwm yam, haum rau lub koom haum uas tsis tshua muaj siab.Rau

2. Lub zog ntawm cov kauv bevel iav yog qhov zoo tshaj plaws, thiab cov kev ua haujlwm tsis zoo hauv txhua yam yog qhov zoo tshaj plaws.Muaj ib txheej ntawm kauv bevel iav nyob rau hauv lub tsav ncej thiab lub rear qag ntawm lub tsheb.Nws cov haujlwm yog raws li nram no:
Qhov zoo: lub zog kis tau tus mob siab, tsis muaj kev sib txhuam tsis sib haum, qhov tseeb ntawm qhov sib kis tam sim ntawd, qhov sib kis loj loj, thiab tshwj xeeb tshaj yog tsim rau kev sib kis ceev.
Tsis zoo: tus nqi ntau lawm.Vim yog qhov tseem ceeb ntawm kev tsim khoom thiab kev teeb tsa, nws yog qhov nyuaj rau kev nkag siab qhov zoo tshaj plaws coincidence degree, thiab nws yuav tsum ua kom du.Qhov zoo tshaj plaws yog roj da dej smoothness.
 
3. Helical bevel iav yog ib hom kev hloov kho ua los ntawm spur bevel iav.Piv nrog rau cov iav bevel ncaj nraim, qee qhov tsis xws luag tau raug txhim kho, xws li: qhov sib kis ntawm lub sijhawm tam sim no kuj yog qhov tseeb dua, qhov tseeb ntawm qhov kis tau tus mob siab dua, thiab qhov kis tau tus mob yog siab dua li ntawm cov iav ncaj ncaj.Txhawm rau muab nws yooj yim, kev sib kis yog me ntsis yooj yim dua li cov iav bevel ncaj, tab sis cov qib meshing yuav zoo tshaj vim yog cov khoom tsim.Nws yog haum rau qhov ceev tsis dhau siab.Lub koom haum yuav tsum ua kom du.