Better through the bends
The LL self-steering axle is the economic miracle of all the BPW axles. It shows off its strengths particularly when tight manoeuvring is required in delivery and distribution haulage. Thanks to its greater manoeuvrability on corners and when making turns, you benefit from more straightforward vehicle handling, less tyre wear and lower fuel consumption - over a mileage of 100,000 kilometres that adds up to the impressive amount of approx. 1,000 litres of fuel and more than 4 tyres per vehicle. Just work that out for your entire fleet!
Function of the self-steering axles: LL stands for "load-dependant steering stabilisation" and it describes the unique functional principle of the BPW self-steering axle. Conventional steering axle designs require steering stabilisers powered from an external source - this is not the case with the BPW self-steering axle. The axle beam and axle stub are connected to undulating thrust washers via steering pivots. When driving straight ahead (zero position), the undulations in the thrust washers keep the wheels on track. The weight of the vehicle presses the undulating contours of the upper and lower thrust washers together. The wheels remain stable in the correct forwards position. When the semitrailer follows the tractor unit through a bend, the wheel castor ensures the wheels turn in accordance with the curve radius (the thrust washers slide over one another).
The frictional resistance changes according to the load on the axle. As a result, a steering angle (of 8° to 27°, depending on the vehicle type) is established according to the load, and solely by mechanical control. The drag link connecting the wheels uses a steering lock to prevent the wheels from steering when the vehicle reverses. The steering axle means that the unit corners better and follows the same track as the tractor unit almost identically. The lateral tyre forces arising are optimally distributed between all the axles, for example in a 3-axle vehicle. As every axle experiences significantly lower lateral tyre forces, the mileage of the front axle increases by up to 50% - whereas the rear axle mileage increases by up to 70%.
BPW LL self-steering axles - Features and benefits
- For axle loads from 6.4 t to 14 t
- Versions with disc or drum brake
- Lightest self-steering axle
- Steering stabilisation solely load-dependent
- Significantly lower and more even tyre wear: save more than 4 tyres over 100,000 kilometres
- Significantly lower fuel consumption: up to 1,000 litres over 100,000 kilometres
- Greater manoeuvrability, reduced transport space requirement, fewer expensive incidents of tyre damage
- Less strain on the body, frame and road
- Exact tracking when changing lanes
- Particularly recommendable with the 44 tonnes regulation*
- Simplified installation thanks to optional 3-D trailing arms, no retracted frame required
- Permitted ratio of rigid axles to steering axles 1:1 (also applies with a lifted first axle of a tri-axle suspension)
- Higher resale value
- Cataphoretic dip-coating with zinc-phosphating
*44 tonnes regulation according to § 34 (6) of the German Road Traffic Regulations (StVZO): ,,When an articulated vehicle (...) is transporting (...) a 40 foot ISO container, the gross weight rating is not allowed to exceed 44tonnes subject to the regulations for axle loads and single vehicles."