PRODUCT R&D
BRAKE HOSES Bendix explains that brake hoses might be a small component, but they have a big job When thinking about braking systems, hoses are likely to be well down the list in terms of the components that immediately come to mind for most people. Although brake hoses may not have the same prominence as other components such as brake pads, disc brake rotors, calipers or even the brake master cylinder, the humble brake hose is actually one of the most regulated components of a vehicle. This gives an indication of how critically important brake hoses are to the overall performance of a braking system. In a nutshell, brake hoses are responsible for carrying brake fluid from a vehicle’s brake lines – which are fixed to the car or truck’s underbody – on the last part of the fluid’s journey to the brake calipers which of course are located at the wheels. The fact that there’s wheel movement going on as part of the suspension assembly as well as for steering, means that brake hoses need to flexible yet tough.
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Australian Automotive Aftermarket Magazine July 2022
Another reason they need to be robust is because the brake fluid travels through under high pressure once the brake is applied and the brake master cylinder comes into play. Brake fluid is non compressible, so the pressure that’s generated at the pedal is maintained to deliver the necessary braking force to safely bring a vehicle to a standstill. In order to maintain this pressure, the hose must retain its original shape. It is no surprise then that the regulations and testing that govern the manufacture of brake hoses is strict.
In fact, the testing benchmarks are set in such a way that they are unlikely to ever be replicated in real world driving conditions
Brake hose standards To meet governing DOT and SAE J1401 standards, brake hoses must pass the following tests: • Burst pressures – must withstand water pressure of 4,000 psi for two minutes. • Whip testing – must endure being continually bent for 35 hours under pressure. • Tensile testing – hose assembly must withstand a pull of 325 pounds (approx.
