Iityhubhu zentsimbi ezingenamthungo kwizibiyeli zoxinzelelo oluphantsi naphakathi (GB3087-2018) zikumgangatho ophezulu wekhabhoni yesakhiwo sentsimbi yentsimbi eshushu-isolwe ngokubanda (iqengqelekisiwe) iityhubhu zentsimbi ezingenamthungo, ezisetyenziselwa ukuvelisa imibhobho yomphunga eshushu kakhulu, imibhobho yamanzi abilayo kwizakhiwo ezahlukeneyo zeebhoyila ezinoxinzelelo oluphantsi naphakathi kunye nemibhobho yomphunga eshushu kakhulu, imibhobho yomsi emikhulu, imibhobho emincinci yomsi kunye nemibhobho yezitena ze-arch kwiibhoyila ze-locomotive.

Iziphelo zombhobho wensimbi kufuneka zibe yi-perpendicular kwi-axis yepayipi yensimbi, kwaye i-burrs kufuneka isuswe.GB3087umbhobho wentsimbi eqhelekileyo wenziwe ngokubanzi ngentsimbi eyi-10, 20 eshushu eqengqelekayo okanye ebandayo eqengqelekayo ekumgangatho ophezulu wekhabhoni yesakhiwo, idla ngokufuneka.uxinzelelo lwamanzie, ukuqhwanyaza, ukuvutha, ukucabakunye nezinye iimvavanyo zokuqinisekisa umgangatho wemveliso kunye nokusebenza.