Wheelift Systems introduced its self-propelled trailers (SPT) in capacities up to 100 tons. They were developed for in-plant operation in congested, confined areas and in narrow intersecting aisles. Highly maneuverable, the Wheelift SPTs feature computerized independent steering, on-center rotating front axles, remote control operation, low-profile design, and on-board power generation. Each SPT has two on-center rotation, electronically steered and driven independent axle assemblies on the front end. At the rear are two fixed-direction rocker beam–mounted axle assemblies that each has lateral articulation capability to ensure fully equalized load sharing.
The trailers are powered by a 480 V, 3-phase AC, LP gas engine generator. A shore power back-up option is offered. While the SPTs can be built to a wide range of capacities and dimensions, the pictured 100-ton unit has an overall length of 21 feet, is 8 feet wide, and has a deck height of 27 inches. (http://www.selfpropelledtrailers.com)