SKF Developed The ModulD Wheel-end for Commercial Vehicles

SKF Developed The ModulD Wheel-end for Commercial Vehicles SKF has developed the ModulD wheel-end for commercial vehicles as part of a joint project with Haldex. The system incorporates a caliper brake with dual-discs and combines high torque and lightweight characteristics due to the use of compact SKF hub units. SKF developed a tailor-made integrated slim-line hub unit for use in the wheel-end. The ModulD solution incorporates a hub unit of extremely slim design that offers a precisely adjusted interplay between the bearing, grease and seals. The dual discs are positioned on the toothwork of the integrated hub, interlocked, with five specially designed springs permitting lateral displacement to ensure wear compensation and clearance. They also ensure that the contact between the hub and disc does not become too close, to avoid excessive heat dissipation in the hub.The disc virtually floats on the hub, keeping noise to a minimum.The low thermal stress on the hub results in long hub life and, at the same time, means less strain for the tyres. The new brake concept also offers retrofit potential with customers able to use the old axle and its journal; the hub is suitable for nearly all journals if the bearing unit bore diameter ranges between 80 and 105mm.The brake itself is extremely versatile, too.For 572mm wheels, Haldex uses discs brakes that are 533mm in diameter.The result is a weight-optimised solution that saves up to 90kg per triple-axle suspension. Using the same hub and clamping unit but a 495mm disc, the Haldex modular concept also enables the construction of a fixed caliper brake for 195mm wheels, which is ideal for applications where minimising weight is crucial.Compared with conventional 572mm wheel ends, it reduces the weight per axle by as much as 35kg. The SKF-Haldex wheel end weighs about 15% less than current conventional solutions, which typically weigh some 25kg per axle.The system is also suitable for heavier clamping torques. With a robust design and fitted with a dual disc, the fixed caliper brake is capable of providing clamping torques of up to 35kNm for use with future generations of vehicles. The wheel end has been designed for one million kilometres of maintenance-free operation.When the discs are worn down, they can easily be drawn off the axles as soon as the wheel flange has been dismounted and the locking device opened.The pads can also be easily replaced from overhead without having to dismount the wheel flange or other components.