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%.
Tyre Mileage (km) in distribution haulage
Fuel Saving from BPW self-steering axle in proportion to mileage - here taking the example for distribution haulage
Tyre Consumption on a three-axle vehicle over 100 000 km, used in distribution haulage
The BPW self-steering axle guarantees compliance with the turning-circle regulations, even when the first axle is lifted
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)