Development of High Performance Hemi-Spherical Plain Bearings, Applied for Miter Gates

摘要

This paper will discuss the development of a self-lubricating, maintenance-free hemispherical plain bearing as an alternative to conventional greased bronze bearings which can pose an environmental hazard. The bearing was developed at the request of the Panama Canal Authority, which was seeking to reduce downtime and eliminate the use of grease in more than 90 miter gates along its 80 km waterway. The performance advantages and environmental benefits of the new bearing will be discussed from the enduser’s perspective. The design process began with the collection and analysis of application design and performance data. This together with details of a standard test procedure defined by ACP, USACE and Powertech helped define the project and product performance objectives. House of Quality methodology was used to translate this Voice of the Customer information into internal product language. This process identified the need for a new polymeric material and novel design concept. The proposed hemispherical design and complex load interactions made engineering calculations difficult, so computer-aided design and analysis techniques were used for structural evaluation of the concept. The resulting bearing features a matrix of PTFE lubricant plugs covering approximately 75% of the bearing surface area, compared with typical maximum coverage of 30% in traditional plugged bronze bearings. This enhanced design provides extremely low friction and demonstrates that high-performance, self lubricating bearings can reduce the cost of ownership and make a meaningful contribution toward environmental protection.