Umthelela empilweni yokubumba

(1) Ukunemba kwendlela eqondisayo yokubumba. Ukuqondisa okunembile nokunokwethenjelwa, ukunciphisa ukugqokwa kwezingxenye zomsebenzi wesikhunta, ukugwema umthelela wokungakwazi ukubumba kanye ne-concave isikhunta, ikakhulukazi igebe elingashayi mkhuba nelincane elishiyayo, ukufa okuhlanganayo nokufa okuqhubekayo kwesiteshi kuyasebenza kakhulu. Ukuze kuthuthukiswe impilo yesikhunta, ukwakheka kumele kususele kuhlobo lwenqubo nokunemba kwezingxenye, ukukhetha okulungile kwefomu lokuqondisa nokunemba kwendlela eqondisayo.

(2) Amapharamitha wejometri ofile (i-convex, concave die). Ukwakheka kwesikhunta se-convex ne-concave, i-clearance clearance kanye ne-fillet radius hhayi nje kunethonya elikhulu ekwakhekeni kwengxenye yokugwazwa, kepha futhi kunomthelela omkhulu ekugqokeni nasekusebenzeni kwempilo yokubumba. Isibonelo, ukucaciswa okufanako kwesikhunta kuthinta ngqo ikhwalithi yokungabinalutho nempilo yokubumba. Ngezidingo zokucacisa okuphezulu, inani legebe elincane kufanele likhethwe kumklamo; ngaphandle kwalokho, igebe lingandiswa ngokufanele ukuze kuthuthukiswe impilo yesikhunta.