Comparison of the gear load capacity obtained by using standards and finite element method

Zupčanici spadaju u skupinu strojnih elemenata čija je svrha prenošenje snage i gibanja. Jedan su od najzastupljenijih strojnih elemenata unutar te skupine te njihovo konstruiranje predstavlja vrlo kompleksan inženjerski problem. Zatajenje zuba u korijenu najčešći je način zatajenja zupčanika u industriji. Zbog toga se često javlja potreba za što boljim razumijevanjem njegova nastajanja. U ovom radu su obrađene dvije metode određivanja naprezanja u korijenu zuba i određivanja zamornog vijeka zupčanika. Proračun je prvo proveden prema standardu Međunarodne Organizacije za Standardizaciju ISO 6336: Proračun nosivosti cilindričnih zupčanika s ravnim ili kosim zubima, a nakon toga numerički, metodom konačnih elemenata. Proveden je proračun nosivosti i zamornog vijeka prema standardu za slučaj sa i bez utjecaja tankog vijenca, dok su numeričke simulacije provedene za ta dva slučaja, kao i za slučaj kada se uzima u obzir trenje i centrifugalna sila.Gears are machine elements that are used to transmit power and motion. They are one of the most represented machine elements in that field and the process of designing them is a very complex engineering problem. Tooth-bending fatigue is the most common way of gear failure in the industry. For this reason, there is often a need for a better understanding of its cause. In this paper, two methods of determining the tooth root bending stress and the fatigue life of gears are discussed. According to the standard of the International Organization for Standardization ISO 6336: Calculation of load capacity spur and helical gears, and numerically, using the finite element method. The calculation of load capacity and fatigue life according to the standard was carried out in two cases, with and without the influence of a thin rim, while numerical simulations were carried out for those two cases and two additional cases, when friction and centrifugal force were taken into consideration