Umunyururu wa moto ukorwa n'iki?

(1) Itandukaniro rikomeye riri hagati y’ibikoresho by’icyuma bikoreshwa mu bice by’umunyururu mu gihugu no mu mahanga riri mu byuma by’imbere n’inyuma. Imikorere y’ibyuma by’umunyururu isaba imbaraga nyinshi zo gukurura no gukomera bimwe na bimwe. Mu Bushinwa, 40Mn na 45Mn muri rusange bikoreshwa mu nganda, naho 35 ibyuma ntibikunze gukoreshwa. Imiterere y’ibinyabutabire by’ibyuma bya 40Mn na 45Mn ni binini kurusha iby’ibyuma byo mu mahanga bya S35C na SAEl035, kandi hari ubugari bwa 1.5% kugeza kuri 2.5% ku buso. Kubwibyo, ibyuma by’umunyururu bikunze kugira ikibazo cyo kuvunika vuba nyuma yo kuzimya no gushyushya bihagije.
Mu gihe cyo gupima ubukana, ubukana bw'ubuso bw'icyuma gifunga nyuma yo kuzimya buba buri hasi (munsi ya 40HRC). Iyo ubunini bw'urukuta rw'ubuso bumaze kwangirika, ubukana bushobora kugera kuri 50HRC, ibyo bizagira ingaruka zikomeye ku mutwaro muto w'icyuma gifunga.
(2) Inganda zikora ibikoresho by’abanyamahanga muri rusange zikoresha S35C na SAEl035, kandi zikoresha amatanura agezweho yo mu mukandara ukomeza gukoreshwa. Mu gihe cyo kuvura ubushyuhe, hakoreshwa ikirere gikingira mu kuvura no kongera gukoresha umwuka. Byongeye kandi, hashyirwaho uburyo bukomeye bwo kugenzura ibikorwa by’aho hantu, bityo amasahani y’iminyururu ntakunze kubaho. Nyuma yo kuzimya no gushyushya, havuka kuvunika nabi cyangwa ubukana buke bw’ubuso.
Isuzuma rya metallographic rigaragaza ko hari imiterere myinshi ya martensite nziza isa n'urushinge (hafi 15-30um) ku buso bw'icyuma nyuma yo kuzimya, mu gihe igice cy'imbere ari imiterere ya martensite isa n'umurongo. Mu gihe cy'ubugari bwa plate imwe y'icyuma, umutwaro muto wo gukurura nyuma yo gukonjesha uba munini kuruta uw'ibicuruzwa byo mu gihugu. Mu bihugu by'amahanga, plates zifite ubugari bwa 1.5mm zikoreshwa muri rusange kandi imbaraga zo gukurura zikenewe ni >18 kN, mu gihe plates zo mu gihugu muri rusange zikoresha plates zifite ubugari bwa 1.6-1.7mm naho imbaraga zo gukurura zikenewe ni >17.8 kN.

(3) Bitewe n’uko ibikenewe ku bice by’iminyururu ya moto bikomeje kunozwa, inganda zo mu gihugu no mu mahanga zikomeje kunoza icyuma gikoreshwa mu gukora iminyururu, amaboko n’imizingo. Umutwaro muto wo gukurura cyane cyane imbaraga zo kwangirika k’umunyururu bifitanye isano n’icyuma. Nyuma y’uko inganda zo mu gihugu no mu mahanga ziherutse guhitamo icyuma cya 20CrMnTiH nk’igikoresho cyo gukurura aho kuba 20CrMnMo, imbaraga zo gukurura umunyururu ziyongereyeho 13% kugeza kuri 18%, kandi inganda zo mu mahanga zakoresheje icyuma cya SAE8620 nk’igikoresho cyo gukurura umunyururu n’amaboko. Ibi nabyo bifitanye isano n’ibi. Imyitozo yagaragaje ko ari uko gusa kunoza icyuho kiri hagati y’umunyururu n’amaboko, kunoza uburyo bwo gutunganya ubushyuhe n’amavuta, ubushobozi bwo kwangirika n’imbaraga zo gukurura umunyururu bushobora kunozwa cyane.
(4) Mu bice by'umunyururu wa moto, icyapa cy'imbere n'agasanduku, icyapa cy'inyuma n'agasanduku byose bifatanye hamwe n'aho bihurira, mu gihe icyapa n'agasanduku bifatanye neza. Guhuza ibice by'umunyururu bigira ingaruka zikomeye ku kudashira kw'umunyururu no ku mutwaro muto wo gukurura. Dukurikije ibihe bitandukanye byo gukoreshwa n'imitwaro y'ibyangiritse by'umunyururu, ugabanyijemo urwego rutatu: A, B na C. Icyiciro cya A gikoreshwa mu gutwara ibintu biremereye, byihuta cyane kandi by'ingenzi; Icyiciro cya B gikoreshwa mu gutwara ibintu muri rusange; Icyiciro cya C gikoreshwa mu guhindura ibikoresho bisanzwe. Kubwibyo, ibisabwa mu guhuza ibice by'umunyururu wa Class A birakomeye cyane.