24–32 tonne Canefield locomotive final drive improvement

Wilmar Sugar has 20 Baldwin B-B locomotives ranging in mass from 24 t to 32 t and the Australian sugar industry has an additional 25. The first to enter service was the 26 t KILRIE in June 1972. Since then, the loads being hauled by the Baldwin locomotives have increased, to ensure an adequate supply of cane to the sugar mills, as their crushing rates have increased. This load increase has taken its toll, particularly on the drivelines which include the final drives. Each Baldwin B-B locomotive has two driving and two driven final drives. Current typical service life for the Baldwin locomotive final drives between rebuilds is not acceptable. Furthermore, the final drives have now been rebuilt many times and have surpassed their design service life. This is reflected in their increasing maintenance costs and in-service failures. An option for continuing to operate the range of Baldwin B-B locomotives, is to replace their current final drives. Following extensive global driveline specialist enquiries to identify a suitable commercially available solution, or part solution, it became apparent that it was necessary to undertake a first-principles approach to custom design the final drives for the specific duty. This process has prompted the reassessment of the current range of designs for the final drives. Evaluation of the driving and driven final drive duty requirement for the 24–32 t application against internationally recognised engineering standards determined that the current design final drives were not appropriate for the current duty. The design process for the revised final drives identified several reliability concerns for the current designs, with the expected duty requirement. One alternative to obtain an improved service life for the current designs is to reduce the load limits for the range of Baldwin locomotives in service. An alternative approach is to design final drives capable of sustaining the required service loads. A benefit that could be realised with this approach is that one driving and one driven final drive could be designed to fulfil the duty requirement of the 24–32 t application, minimising spares requirement and inventory cost. This paper presents the reliability concerns identified with the current final drives and the process adopted to revise the design to overcome cost and reliability concerns for the 24–32 t application. An additional outcome of this process, is that a driving and a driven final drive design has been realised that can be integrated into new locomotive designs to replace the current 0-6-0 locomotives.