Prototypes of a new bearing called the Mega-tonne, which is designed for 45-tonne axleloads, have been completed and will soon start trials with operators in Australia.

"Customers also want more reliable bearings," Mr Jay Monaco, vice-president of global engineering with Amsted Rail, told IRJ at Railway Interchange. "The Mega-tonne can work with an AAR Class G axle, and with minor modifications to the sideframe pedestal, we can accommodate this larger bearing."

The next phase to move from 40 to 45-tonne axleloads involves developing an appropriate bogie. "It is quite a challenge to produce a 45-tonne axleload bogie because all the equipment is larger and needs more space," says Monaco. "Wagons are also becoming lighter but the loads are getting heavier which affects dynamic performance, and we also need good curving performance.

"Our Super Service Ride Master bogie will act as the platform for the new 45-tonne bogie," says Monaco. "We have produced special suspension springs for it and made new castings. These are now going through structural and dynamic tests to AAR standards to validate the design and we should be ready to start field trials by the end of the year."