Terminal tractor-trailers (TT) are among the commonest types of equipment found at container terminals. The history of tractor-trailers began at the inception of containerization, when road trucks were modified to better suit conditions at container terminals. TT engines were modified for additional stresses to support ‘stop and go’ type operations, a shorter wheel base and increased steering angles made them more manoeuvrable and capable for precise trailer spotting, and ‘open corner’ trailer design allowed access to install or remove twist locks while a container was still on the trailer.
The concepts for tractor-trailers and road trucks, however, are the same:
- The vehicle comprises prime mover (tractor) and towing trailer
- The vehicle is powered by a high-speed diesel motor and a gearbox selected for the speed and torque required
The Automotive terminal-trailer (ATT), introduced by Gaussin, SA (France), breaks from both of these principles:
The ATT is self-propelled and equipped with a power pack, mounted under the trailer frame. A lightweight cabin is mounted directly on the front axle, while the vehicle requires only two axles. Length of the trailer is 45’ and maximum load is 60t.
The ATT doesn’t have a high-speed motor and a gearbox, instead it has a hydraulic engine which draws power from the diesel engine. The diesel engine itself starts and stops using newly developed hydraulic technology, called HERO.
Furthermore, the ATT is also the latest generation in hydraulic vehicles with fully integrating hydraulic technology. In this configuration, the ‘full’ hydraulic system replaces the conventional drive train with a hydraulic drive train and eliminates the need for a transmission and transfer case. With the ATT, the energy is transferred directly to the wheels by hydraulics.
We should note that Gaussin did not develop this technology overnight. Gaussin has manufactured hydraulic industrial trailers in the past, but it took years of new research and development and a number of new patents to produce this versatile vehicle for container terminals.
The intent of the following analysis is to evaluate objectively the benefits of the system and to outline how terminal operators can capitalise on strengths and exploit benefits of this new technology. As the baseline for the comparison, we are using a typical tractor-trailer system with 45’ terminal trailer, connected to a tractor via a fifth wheel.