The TRIDEC steering system type TR is a mechanical steering system used primarily in heavy distribution transport, such as tank semi-trailers, tippers and gravel trailers. A TR system enables you to steer 1 to 3 axles mechanically, possibly in combination with several rigid axles. The sys-tem is mainly used on flat semi-trailers, but can also be used on semi-trailers with a gooseneck.

The system consists of a fifth wheel plate (which replaces the usual fifth wheel) and an axle mounting frame, which are connected to one another by the steering rods. The TR fifth wheel plate has a king pin and a steering wedge that are automatically locked in the fifth wheel on the prime mover when the trailer is hitched. When the prime mover is turned, the turntable plate in the fifth wheel plate turns with it via the steering wedge thanks to the fixed connection. The steering rod transmits the steering motion via the bearing journal at the top of the turntable plate to the steering transfer lever, from where two steering rods drive the axle mounting frame on the rear axle. If several axles need to be steered, the steering motion is transmitted from the rear axle to the axles in front by means of rods.

The steering rods consist of one part and are fastened at the front and back by steering ball joints. Thanks to this solid connection, the steering motion is transmitted very directly and there is no play on the system. This connection also ensures that the axle cannot be steered in any way other than by the motion of the prime mover. This means that rutting and other external factors do not adversely affect the vehicle's stability.

The TRIDEC TR system is a low-maintenance system. Maintenance is limited to lubricating the turntables a few times a year and testing just a few bolt connections. This is possible because high-quality materials and a durable construction are used. The steering rod bearings patented by TRIDEC, for instance, are entirely maintenance-free, thereby lengthening the trailer's service life. The turntables are sealed using a special seal and are mounted with special shear-resistant bolts, making it no longer necessary to check these bolts. In addition, all lubricating points are centralised at a single, easily accessible point.

Thanks to a unique patented design of the fifth wheel plate and the axle mounting frame, the entire system can easily be removed from below. This saves you a great deal of time during service and renders a floor hatch in the bodywork unnecessary. All TRIDEC products are custom-built, though because standard components are used wherever possible in our systems spare parts are always available.

TRIDEC has an advanced engineering department which is responsible for the entire technical preparation and processing of your order. By means of specially developed software, a turning circle calculation can be made that simulates the road behaviour of your trailer when cornering. Interference checks and construction recommendations provide you with a customised system for your chassis. This gives you a system with the perfect combination between optimum steering and maximum reduction of friction.


Gümaş Otomotiv Sanayi ve Ticaret A.Ş.
Taksim Cad. No:33/A 34437,
Taksim - İstanbul

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