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16-12-2013, 04:23 AM
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MINIMISING THE FACTORS THAT CAUSE BRAKE NOISE, VIBRATION AND HARSHNESS.


Bendix General CT pads are designed to minimise the two key factors that cause brake noise, vibration and harshness (NVH). This ensures that you get great braking performance, with no noise and negligible dust. These 2 key factors are ‘excitation’ and ‘response’.


What is Excitation?


Excitation is created when two surfaces are rubbed together, think fingernails scratching a blackboard, a bow across a violin string – and yes, a brake pad clamping on a rotor. Most brake pads use abrasive friction to slow the vehicle but with Bendix General CT it’s cohesive friction. Bendix General CT brake pads are made using patented Ceramic Technology, an ultra premium ceramic formulation. The Bendix General CT pads transfer a thin film of friction material to the rotor surface. The braking force is achieved by continuously breaking the adhesive bonds between the brake pad and the friction film on the rotor. Cohesive friction is a powerful yet mild process that creates almost no brake dust and less NVH excitation than the aggressive abrasion action of traditional friction materials used by others in the marketplace.


What is Response?


Response is what happens when the braking system experiences friction excitation and the brake pads, rotor, calliper and suspension vibrate and resonate creating sound waves – remember the blackboard screech? Brake Squeal is the result of friction material rubbing on the rotor which causes the rotor and other components including the pad to vibrate. This vibration causes the rotor to act like a speaker.


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Bendix General CT is engineered to minimise vibration response.


The advanced ceramic formulations used in Bendix General CT have a high level of internal damping to absorb vibration and reduce sonic frequency vibrations before they turn into sound. On some parts a rubber and fibreglass composite gasket on the back plate provides additional damping.


The pad geometry, including slots, chamfers, back plate thickness and spigot hole arrangement, is designed to avoid resonant vibration frequencies.


In Bendix General CT we use geometric adjustments which can tune away resonance, eliminating brake squeal.


In most cases geometric tuning is achieved by starting with the OE pad design and fine tuning it in our laboratory. To develop customised geometry specific to the Bendix General CT material formulation the Bendix Product Engineering Laboratory uses a $1.3 million brake noise dynamometer, noise test vehicles and advanced NVH analysis tools. This facility is unique to Bendix and no other friction supplier has this in Australia.


By minimising the NVH excitation and controlling the response, Bendix General CT achieves true noise, vibration and harshness control so your customers will get the benefits of a smoother, quieter and cleaner operation.


For more information, visit www.bendix.com.au (http://clixtrac.com/campaign/?14124)