Delphi TECHNOLOGIES.

Surely every motorist heard that annoying braking noise, for example, when you drive up to the traffic light. The sound is different: a high whistle, screeching, creaking or grinding. Brake noise can be one of the first signs that with your brakes are not all right and something happens to them.

Let’s talk more about braking noise that it causes it, and how to eliminate it.

Turn to the basics. Sound, simply speaking — this vibration. Whether it is a bird tweet, an acoustic guitar or grumble — its vibrations cause air oscillation creating a sound wave. The frequency of these oscillations is determined by the speed of vibration.

The same is true when it comes to brake noise. All brake elements vibrate to one degree or another, creating sound. For the most part, this sound is not perceived by the human ear. However, when the vibration is enhanced, the brake disc starts working as a speaker, making vibration hearing. What is the result? Heard noise when braking.

Noise when braking can be caused by various problems with brake details or installation. Excessive corrosion, jamming or bending guides, partially privable cylinders, accumulated dirt and brake dust, excessive beating, uneven disk thickness or worn brake discs — all this can cause vibration between the disk and the brake block, creating braking noise.

Although the brake system itself is the most frequent source of noise, it can also occur in other nodes of the car. For example, when a vibration is created in braking in the elements of the suspension, steering, as well as in the engine mount and / or transmission elements.

Types of brake noise

Yes, there are various types of brake noise, all of them are determined by the frequency of vibration. For example, slow vibration can sound like a moan, while a faster vibration looks more like a screech. Brake noises can be systematized as follows:

• Vibrations: low-frequency vibrations below 300 Hz. Causes include a bad installation of disk brakes on the hub, damage to the disk, excessive change in the disk thickness and beating.

• VZG: medium frequency oscillations — from 300 to 5 kHz. Causes — Entering the piston of the caliper or guides, improper installation of the pads, strongly worn discs and chips of the friction material.

• Pick: high-frequency vibrations are more than 5 kHz. Usually caused by the vibration of the friction material at the time of pressed to the disk.

• Ultrasound: Very high-frequency oscillations of more than 12 kHz (often above the hearing threshold).

Sometimes noises can sound like grinding. Often it is caused by the lack of friction material pads, and the discs rub metal on metal. And the grinding may mean that a foreign body is stuck between the shoe / disc or disk / powder.

What to pay attention to?

So, you should carefully check the entire brake system, especially the pads, as they are often a good indicator of the emerging problem. Conical wear pads can signal the caliper fault. A damaged base plate suggests an excessive force attached during installation. Changing the thickness of the disk is a faithful sign of vibration.

Other signals are uneven wear of the pads, brake fluid leakage, piston damage and bringing the guide caliper.

To minimize the problems associated with brake noise, it is important to comply with the proven recommendations. They are harmful to list:

• Ensure that all corrosion, accumulated dirt and brake dust removed from the caliper.

• Always clean the open surfaces of the caliper piston before pressing the pistons. Eliminating the piston pressure and removal of old, dirty fluid, opening the pumping unit. Push the piston with a suitable tool. Never use the lever to the friction surface of the disk.

• Clean the plugs of the pads in the caliper thoroughly.

• Check the pistons, seals, anthers and sliding elements on the caliper, make sure that there are no damage, corrosion and that they are capable of sliding.

• Replace all anti-vacrem clips, springs and pins that can lose their spring properties with time or due to high braking temperature.

• Always check the disk on the minimum thickness and the beyon when installing new pads.

• Always check whether the pads are set correctly and they are located correctly in the caliper. They must be freely placed in the brackets to avoid constant contact with disks.

• Never use clamps on brake hoses. Hoses consist of several layers that give them strength. The hose may be damaged or crushed, which will lead to blocking or leakage of fluid.

• Never use lubricants based on mineral oils on details with rubber seals. This will lead to swelling seals.

And now how fights with Delphi noise

Currently, the requirements for high efficiency and reduction in the weight of modern cars led to the fact that modified materials were used in brake details and additional measures to counter vibrations were used.

So, unlike other manufacturers of the secondary market, each Delphi brake pad is made by the OE technology of the lower layer. This layer of noise absorbing friction material with a thickness of only 3 mm provides 83% less noise with vibrations above 70 dB. In addition, it works as a heat insulator and ensures the strength of the pad.

Delphi pads also have an OE configuration, neat grooves and gaskets. Installation kits comply with OE requirements, Delphi multi-layer pads, with various varieties of damping materials. The layers of these materials are accurately recovered to exercise their best qualities. Materials are carefully selected and mechanically connected, clipped and fixed with a hot way to improve noise reduction.

Based on Delphi TECHNOLOGIES