Haldex Heavy Duty brake adjuster specification meets increased customer demands
Commercial vehicle and trailer braking systems pioneer Haldex is showcasing its innovative, new Heavy Duty (HD) specification for its brake adjuster range.
Both Haldex’s AA1, first-generation automatic brake adjuster, and its S-ABA (Self-setting Automatic Brake Adjuster) are now available in HD versions, developed in response to an increasing need for more robust parts; which has been created by EBS braking systems and automatic transmissions putting higher demands on wheel-end components than ever before, even when a vehicle is stationary.
“In the old days, you had to press the brake pedal more to get more force out,” says Patrik Käll, commercial product manager for brake adjusters. “Now EBS and automatic transmissions in stop-and-go traffic can lead to accelerated wear on brake components. This has been the driver for our new product.”
Haldex HD brake adjusters boast a rated torque of 2900Nm, which may not sound like a large increase from the standard 2600Nm, but this difference is highly significant – delivering vastly increased durability. “We have a brake adjuster now that can maintain higher torque than any other available,” says Käll. “We are unique in the market with this.” The innovation is directly addressed to specific customer demands for increased output. “For OEMs with the extra need, this has supported them fully,” says Käll.
To achieve the higher torque rating was no simple task and Haldex implemented several manufacturing advances to create the new component. “We have always hardened our castings, but with the traditional processes you only get a thin hardened layer,” says Käll. “For 2900Nm you need to have a deeper hardening process. This means it needs to be done prior to machining, because if you do deep hardening after machining it can distort the dimensions of the part.”
The new process meant that Haldex had to specify a completely new casting material and develop the new process for the hardening the brake adjuster components and the worm wheel and worm shaft. “It was a long journey, because to produce this is really not easy,” says Käll. “But now we have new material and new processes, which has raised the bar for the rated torque and increased the product lifetime. This is a huge improvement for our customers.”
Despite these internal enhancements, the HD brake adjuster maintains the same external appearance as standard models, ensuring compatibility with existing systems. This seamless integration allows customers to upgrade their brake systems without modifications
A history of innovation
The HD Brake Adjuster is the latest addition to the Haldex range, building on its long-standing reputation as a global leader in this field. The company introduced the first automatic clearance-sensing brake adjuster, the AA1, in 1968. This marked a significant improvement over manual brake adjusters, which required regular maintenance to ensure proper brake function. “With automatic brake adjusters, you always know you have the right clearance – you guarantee the gap and the braking performance,” says Käll. “Haldex actually designed the clearance principle, and the whole global brake adjuster industry is now based on this, instead of stroke."
In 1997, Haldex scored another first as it introduced the S-ABA, the only brake adjuster with a self-setting design that means it functions correctly regardless of the position of its arm. Over the years, Haldex has produced over 100 million brake adjusters, cementing its position as a market leader. The company’s products have become the global standard, with the clearance principle developed by Haldex now widely adopted.
Looking to the future, Haldex remains committed to innovation in the brake adjuster market. Despite predictions that disc brakes would completely replace drum brakes, Käll notes that drum brakes, and consequently brake adjusters, continue to play a significant role in certain applications. "Europe is running with approximately 80% disc and 20% drum,” says Käll. “Drum is used in trucks that are designed for harsh, off-road conditions and some of the fleets of trailers are still in favour of running with the drum solution.”
The HD spec for its brake adjusters highlights Haldex's ongoing commitment to performance, robustness, and reducing total cost of ownership for its customers in the commercial vehicle sector, meeting current market demands and also proving Haldex’s ability and willingness to solve new challenges in braking systems as they emerge.
