Abstract
Single row, angular contact, spherical roller bearings were designed, analyzed, and tested to study their feasibility in a high speed (1.15 million DN) spiral bevel input pinion application. A mathematical formulation, modeling the mechanics of internal motions, load and stress distributions, lubricant flow, sliding friction, heat generation and heat transfer, was developed to analyze the bearing performance and predict operating characteristics. An interactive computer program, capable of running on a DOS PC, was then developed to solve the bearing model for the given parameters of geometry, materials, loads, and speed. The computer program, named SASHBEAN (Sikorsky Aircraft Spherical Roller High Speed Bearing ANalysis), also provided the capability of “lumped capacity” thermal analyses of the bearing and its supporting mechanical system. Six test bearings, conforming to a 216 cylindrical roller bearing OD (140 mm) and ID (80mm), were manufactured using Carpenter Pyrowear® Alloy 53 steel rings. Both conventional (with steel rollers) and hybrid (with silicon nitride rollers) configurations were built and tested under different setup conditions of loads (radial and axial), speed, and lubrication. Excellent correlation was found between the full scale test data and the computer analyses results. The analysis also provides an excellent comparison of the performance characteristics of an hybrid bearing with those of an “all steel” bearing for this high speed transmission application.