Car Noise Guide: How to identify tire noise in car noise

Tire noise. The general tire noise is mainly composed of three parts:

air noise caused by the air flow between the tire tread gap and the air disturbance around the tire;

Tire vibration noise caused by the vibration of the carcass and tread parts;

Road noise caused by uneven road surfaces.

Tire noise is inevitable, even if you change to the so-called low tire noise tires have no effect, the key is to look at the sound absorption and sound insulation effect of the vehicle itself, now the new car firewall below 300,000 is basically not sound absorption and sound insulation, resulting in engine sound and tire noise through the dashboard, chassis fenders into the car.

Solution: Tire noise is generally caused by tire and tread vibration or tread and ground friction impact, and with fenders, fenders.

The vibration of other components is amplified and transmitted into the car, so our solution to reduce tire noise can be solved by attaching sound insulation materials to the doors, door edges, above the wheel arc, fenders and chassis.

Wind noise. Wind noise refers to the pressure of the oncoming wind in the process of high-speed driving of the car has exceeded the sealing resistance of the door into the car, the faster the driving speed, the greater the wind noise (mainly through: the four-door sealing gap, including the overall thin steel plate generation and transmission).

When the sound is transmitted into the car, if there is no sound-absorbing and sound-insulating material to absorb and block, the noise will continue to refract and overlap to form a resonant sound.

Solution: Wind noise is formed because the pressure of the wind exceeds the sealing resistance of the door, so strengthening the sealing resistance is the most direct and fundamental solution, and the door sealing strip and inner sealing strip can solve this problem very well.

The tightness of the car is still very important, what should we pay attention to when choosing a car weatherstrip?

The elasticity of the sealing strip.

Greater elasticity and flexibility enhance the sealing effect and increase the service life of the sealing strip.

3M adhesive backing. The sealing strips produced by regular manufacturers are made of 3M adhesive, which has strong adhesion and can be firmly pasted without adhesives.

Waterproof slots. High-quality seals are equipped with waterproof grooves to increase waterproof performance.

Smell. The sealing strip produced by regular rubber is shiny, no obvious odor, non-toxic and harmless. If there is a clear odor, car owners should be cautious, after all, the air quality in the car has been emphasized.

Issue. In fact, the "whole body" of the car is a source of noise, and when the car is noisy, it is necessary to find out the different noises on the car in a targeted manner, so as to prescribe the right medicine. There are four sources of general car noise:

Engine noise, tire noise, noise in the air, and noise caused by body structure.

Tire noise: tire noise is the vehicle at high speed, the tire and the road friction generated, depending on the road conditions to determine the size of the tire noise, the worse the road conditions, the greater the tire noise, in addition to the asphalt pavement and the concrete pavement produced by the tire irritability is very different.

If the tire noise is too large, you should check the tire tread, whether you gnaw the tire, if you gnaw it, it is a four-day stupid wheel alignment problem, just do it, if you don't gnaw, the noise is still big, then change the tire + do fender sound insulation, you can use silent tires, the noise will be less.

Tire noise is generally composed of three parts: one is the air noise composed of the air flow between the tire pattern gap and the air disturbance around the tire, and the other is the tire vibration noise caused by the vibration of the carcass and the tread part; The third is the noise caused by the uneven road surface, and the friction between the tread and the ground when driving on the potholed road.

<> "How to Diagnose Noise Problems in Cars?"

When your car makes all sorts of noises, it means that you should repair your car in some way, or your car will break down. Engine noise, road noise, and tire noise are all structure-borne noise, and its main production is vibration, and the most reasonable solution is to control vibration. Adding a damping plate and a sound-absorbing pad can solve road noise and tire noise well.

However, car maintenance is quite expensive, so the first thing you should do is identify the fault, check and fix simple problems. Learn to recognize the noise of your car, then find and check if the car parts are working properly.

Tap the engine with a hammer and listen for the sound it makes, check the fuel tank to see if the valve or camshaft is worn. This is what you have to do as a repairman.

Close the valve when igniting and listen for the tempering.

Feel the stability of your car when accelerating. Fuel with a high octane rating is burned to the engine.

Refer to your car's owner's manual to find your car's power steering belt. When turning the steering wheel, with a screech, adjust the power steering belt until it fits snugly against the pulley.

Refer to your car's owner's manual to find your car's fan belt. When you're speeding up your car, if you hear a screeching sound, it's time to replace your fan belt.

When you hear your car's engine hissing, it means that the hose inside your engine is leaking. If you can find a specific location for the breach, you can find a temporary remedy.

When you hear a scream when you brake, your car's brake pads are worn out and need to be replaced.

Of course, it is different, and the noise produced by different materials of tires is not the same. Tire noise is one of the main car noise, car tire noise is due to the car in the process of driving, the tire and the ground contact friction, in the friction will inevitably produce noise. When the car is moving very fast, tire noise will also increase, which is unavoidable.

When we are driving on potholes, the tire noise of the car will be especially severe, and not only the tire noise, but we will also hear the shaking of other parts on the chassis of the car, which can make people feel very irritated.

Therefore, we can see that car tire noise is unavoidable, although it cannot be avoided, but we can alleviate tire noise to a certain extent. For example, we can choose those silent tires with more detailed textures, so that their tire noise will be a little lower than that of other ordinary tires.

In addition, we can also glue a layer of cotton cloth to the inside guard of the tire, which is very useful for reducing tire noise. In fact, tires will more or less form a certain amount of noise when running, so we can slow down when driving, so as to reduce tire noise.

The noise of car tires is a small problem, and it is a big problem when the wheels make abnormal noise, and if we can't eliminate the hidden dangers in time, it will bring very big safety hazards. When the tire crackles, most of the tires are pierced with nails or gravel, when we hear this sound, we must send it to the repair shop for repair in time.

The life of car tires is generally about eight years, or the tires need to be replaced once after driving about 80,000 kilometers. However, there is no unified standard answer for tire life, which has a lot to do with the degree of wear and tear of the tire. And some car owners often drive through some places with poor road conditions, which is very damaging to car tires.

During driving, the noise generated by the suspension system of the car and the noise generated by the tires are transmitted to the vehicle through the chassis. The noise generated by different suspension methods, different tire brands, different tire patterns, and different tire pressure is also different.

Noise from car tires. Different. The quality of the tires is not the same as the hardness and softness.

Tire noise: The noise caused by the friction between the tire and the road surface.

After the car starts, there is a clangling noise in the engine box Not small or big After stepping on the clutch, this noise disappears This sound sometimes has and sometimes does not Please give me an analysis of what is wrong? Clutch release bearings?

It is simply impossible to eliminate it completely, and it can only be weakened by finding a way. The engine working noise is the engine will have, the high-quality engine is finely made, the design is reasonable, the vibration is small, the muffler system performance is good, such an engine, the sound is small, and the sound insulation of the engine compartment is also good. Poor quality engine production accuracy is low, some parts are unreasonable in design, large movement, muffler performance is not good, vehicle engine compartment sound insulation is poor, such a car engine noise is large, common in pure domestic cars.

Tire noise, the use of high-quality tires, you can effectively reduce the driving noise of tires on paved roads, such as Michelin, Shiqiao, Continental and other international brand tires, all have tires with low tire noise as the selling point, this "silent" effect is derived from excellent design and high-quality rubber. The road tire noise tires, such as off-road tires, all-round tires, snow tires will produce relatively large tire noise when driving on the road due to the different use of different focuses, of course, miscellaneous, unreasonable design, poor quality tires, there will also be relatively large tire noise. Road noise and tire noise have some relationship, but now it is mostly understood that tires and different quality and process road surface produce different noise, so in the case of a certain tire performance, the more delicate the surface of the road surface, the less noise.

Wind noise, this is due to the car driving, air flow and impact on the body of the noise, this problem consists of two parts, one is whether the body shape design can more effectively control the wind noise, the other is how the overall sound insulation performance of the car body, the shape design is reasonable, the sound insulation performance of the car, at the beginning of the design and forming, may have to be repeatedly tested in the wind tunnel, or use the computer simulation wind tunnel system to test the wind resistance of the car body, there is a very reasonable design concept and rigorous work attitude is the key. Just ask, how many domestic cars have done or have considered doing wind tunnel testing. How does sound work out?

Vibration, the car engine starts running, driving on the road, these will have movement, vibration and friction, so how can there be no sound? Therefore, these "noisy" sounds can only be reduced, not eliminated.

1. Engine noise.

In addition to the mechanical sound emitted by the engine block, it also includes the air intake system noise, that is, the high-speed gas enters the cylinder through the air filter, intake pipe, and valve, and during the flow process, a strong aerodynamic noise is generated. Engine noise is mainly transmitted into the cockpit from the fire barrier and the front floor of the cab.

2. Tire noise.

The general tire noise is mainly composed of three parts:

1) It is the air noise caused by the air flow between the tire pattern gap and the air disturbance around the tire.

2) It is the tire vibration noise caused by the vibration of the carcass and tread part.

3) It is the road noise caused by the uneven road surface.

3. Air noise.

1) Wind noise is the noise caused by the pressure change caused by the separation of the air flow around the body.

2) Air leakage, or suction sound, is the noise generated by the interaction between the inhalation of the cab and the body gap and the airflow around the body.

3) Other noises, including cavity resonance, etc.

4. Body structure-borne noise.

It is mainly affected by two factors.

1) It is the vibration transmission mode of the body structure.

2) It is the noise generated by the metal components on the body due to the vibration generated by the action of the inside and outside.

The noise in the car is mainly caused by the noise of mechanical components such as the engine (engine noise), the friction sound between the tires and the ground (road noise), the collision and friction sound caused by the car breaking through the air curtain (wind noise), and the sound of the external environment entering the car (such as the sound of a large container truck roaring by). .It is composed of internal noise caused by vibration of cockpit interior panels and other components.

The noise in the car is mainly low-frequency noise (250Hz --500Hz), which is extremely penetrating and is also a difficult part of acoustic sound insulation technology to deal with.

Surveys show that motor vehicle noise accounts for urban traffic noise. The propagation of vehicle noise is closely related to the number of roads and the size of traffic measurements. In a city with narrow pathways and high-rise buildings on both sides, the noise reflects back and forth, making it even more noisy.

The same noise source sounds 5-10 decibels louder on the street than in the open ground. Among motor vehicles, the noise of heavy vehicles such as trucks and buses is 89-92 decibels, while the noise of light vehicles such as cars and jeeps is about 82-85 decibels. The speed of the car also has a great relationship with the noise level, the faster the speed, the louder the noise, the speed of the vehicle is increased by 1 times, and the noise is increased by 6-10 decibels.

Bottom AThe underfloor is not well insulated, which makes it easy to transmit road noise to the cockpit. Many low-to-mid-range cars have only a few shock-absorbing rubber sheets and a small number of sound-absorbing blankets installed on the chassis of the factory.

b.Poor assembly of the suspension system, loose assembly, or aging and faulty fittings do not effectively reduce vibration.

c.The thickness of the sheet metal process and the iron sheet used in the whole vehicle is not enough. Tire AThe sound of the tires rubbing against the ground during driving is transmitted into the cockpit from the wheel arches.

b.Vibration noise caused by uneven road surfaces is transmitted into the cockpit. Doorpost ADue to poor assembly or resonance with the car body.

b.The gap in the door post causes wind noise at high speeds.

c.The cavity inside the door pillar causes resonance with the body. Primer AThe noise and vibration of the engine is transmitted into the cockpit through the firewall.

b.Under the instrument panel, the noise of the road from the firewall into the cockpit. Roof The roof sheet metal is too thin, causing resonance with the body. Assembly Various noises caused by poor assembly or design, such as common loose screws and aging of shock-absorbing rubber pads.

To carry out sound insulation modification for your car, the owner needs to first understand the main noise of the car** and the degree of noise impact felt when driving, and then choose a noise reduction construction plan according to your needs.