Post by Muhammad Umar

Authors: Muhammad Umar, Sammar Hayat, Muneeb Ahmad Supervisor: Sir Dr Jafar Hussain Objectives Analytically select deep groove ball bearings for a stepped shaft subjected to out-of-phase gear loading. Satisfy a rigorous design life of 80x10^6 revolutions while maintaining 90% overall system reliability. Validate classical equivalent dynamic load calculations against manufacturer data using the SKF Product Select tool. Methodology Force Resolution: Resolved spatial gear forces (P_r = 0.466 P_t) across horizontal and vertical planes to calculate support reactions. Dynamic Loading: Assigned the 3.5 kN axial load to the locating bearing and calculated the equivalent dynamic bearing load (F_e = XVF_r + YF_a). Reliability Adjustment: Applied a Weibull reliability adjustment for a two-bearing series to establish the minimum basic dynamic load rating (C_{10}). Software Validation: Modeled the analytically derived specifications in SKF Product Select to evaluate fatigue life, frictional power loss, and static safety at 1000 rpm. Results Load Analysis: The classical static analysis produced equivalent dynamic loads of 7.07 kN for the floating bearing and 8.084 kN for the locating bearing. Component Selection: Standardized 55 mm bore SKF 6211 deep groove ball bearings were selected, offering a dynamic load rating of 46.2 kN, safely exceeding the 40.87 kN requirement. Validation: The SKF software precisely matched the analytical loads and projected a minimum rating life of 3110 hours, comfortably surpassing the required 1333.3-hour operational threshold