Wheels provide a vehicle with a road coating, the transfer of traction and brake efforts. Excessive wear of tires negatively affects such characteristics as permeability, dynamism, controllability and smoothness, as well as fuel consumption and noise level. Tire condition is one of of essential factorsaffecting the safety of the car movement.
Rules road The maximum tire wear is set, which is defined as the height of the tread pattern. This parameter is set for each category of vehicles separately:
- For passenger cars and trailers it should exceed a value of 1.6 mm.
- The same indicator for winter tires, as well as all-season (marking "M + S") - not less than 4.0 mm.
- Cars used for the carriage of goods - 1.0 mm and more.
- For buses - not less than 2.0 mm.
A natural question arises how to determine the wear of tires on their own and what signs indicate the unsuitable tires to further operation. Vehicle manufacturers recommend in front of the departure to inspect all the wheels and check the pressure in them. These simple actions will help to avoid many troubles on the road.
Automotive tire wear degree: Methods of determination and effect on traffic safety
The wheel in the process of movement affects significant mechanical loads, which are caused by the following factors:
- Weight vehicle.
- Centrifugal forces from wheel rotation.
- Efforts arising from coating interaction.
The last factor is decisive, especially in our country, where the condition road roads In many areas, far from perfect. In addition to poor-quality coverage with a significant amount of holes and the elevated rubber wear cause:
- Wrong selection of tires for the season and high-speed mode.
- Unsatisfactory technical status chassis, suspension, steering mechanism and brake system.
- Overpens vehicle.
- Non-compliance with tire pressure set values.
- Driving style with frequent and intense overclocking, turns and braking.
- Violation of storage conditions seasonal rubber and installation technology.
Existing road rules directly prohibit tire operation with the following types of damage:
- The height of the pattern is less than the values \u200b\u200bprovided for this type of vehicles.
- Tire tread wear degree indicator uniform wear Appeared at the bottom of the treadmill groove.
- Tire integrity disorders: cuts and breaks: through, exposing cord and superficial.
- Deformation: swelling on the side surfaces and treadmill.
- Solid or complete tread depletion from the base.
For uneven wear Automotive tires Tire wear indicator is checked in two sections. The appearance of them indicates the unsuitability of the wheels to further use. The use of such tires can lead to a loss of vehicle management, lifeling and increasing fuel consumption. With significant damage to the construction of the tire, it is possible to complete its destruction on the go with unpredictable consequences.
The tire wear pattern says a lot about the technical condition of the car and the style of driving its owner, in particular:
- The development of outdoor running lanes indicates a long-term ride at low pressure.
- Wear with stains located in different places of the tread, directly indicates the wrong balance of the wheel and malfunction of the shock absorbers.
- The low tread height in the central part of the treadmill indicates the operation of the tires at elevated pressure.
- Wear inner Tires or Outdoor Parts Shows Wheel Installation Corners.
The diagonal production of the treadmill protector clearly demonstrates the commitment of the car owner with an aggressive driving style.
Methods of determining the degree of wear of automotive tires
The operating traffic rules directly prohibit the operation of motor vehicles with tires that are not relevant to the established requirements. How to check tire wear and not get into the unpleasant situation on the road? It is possible to do it yourself, but it is better to contact the specialists. The method of determining the degree of wear of the tread is as follows:
- Measurements are made using a special tool: depth gauge. It is possible to use a caliper and even breeding agents such as a ten-way coin as a template.
- The depth of the tread pattern with uniform wear is monitored in a separate area area, which is at least 1/12 on the size of the treadmill.
- The drawing height is determined in places with the greatest tread production. If the edge is present in the center, then the measurements are made by its edge.
With uneven wear of automotive tires, the test is performed on several sites, the total area of \u200b\u200bwhich is equal to the value specified in the first paragraph. Measurements are made at different points with the greatest work out, the smallest value is taken into account.
Monitoring the status of the tread should be entrusted by the tire-tire specialists of our autotech center, which have extensive experience in conducting such operations. Wizards not only determine the possibility of further use of tires, but also indicate possible malfunctions car. Consultations on the rules and conditions of seasonal storage of rubber will be alike.
Tires whose wear exceeded extremely valid values \u200b\u200bsignificantly reduce car handling and can cause a traffic accident. In this case, the rule should be followed: I erased the tire - the replacement of the pair, while the preserved rubber can be used as "spares".
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Federal Agency |
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NATIONAL |
GOST R. (ISO 13325: 2003) |
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With road surface
When moving in rolling
ISO 13325: 2003
Tyres - Coast-by Methods
For MEASUREMENT OF TYRE-TO-ROAD SOUND EMISSION
(MOD)
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Moscow |
Preface
Objectives and principles of standardization in Russian Federation Installed by federal law of December 27, 2002 No. 184-FZ "On Technical Regulation", and the rules for the application of national standards of the Russian Federation - GOST R 1.0-2004 "Standardization in the Russian Federation. Basic provisions "
Information about standard
1. Prepared by Open Joint-Stock Company "Research and Research Center for Control and Diagnostics of Technical Systems" (OJSC NIC KD) based on its own authentic translation of the standard specified in paragraph 4
2. Submitted by the Technical Committee on Standardization of TC 358 "Acoustics"
3. Approved and enacted by order of the Federal Agency for Technical Regulation and Metrology of December 25, 2007 No. 404-st
4. This standard is modified with respect to the international standard ISO 13325: 2003 "Tires. Measuring the noise produced by tires when interacting with the road, method of movement by rolling "(ISO 13325: 2003" Tyres - Coast-by Methods for Measurement of Tyre-To-Road Sound Emission ") by making technical deviations, the explanation of which is given in the introduction to this Standard.
The name of this standard is changed relative to the name of the specified international standard for bringing in line with GOST R 1.5-2004 (subsection 3.5)
5. Entered for the first time
Introduction
This standard has the following differences from the International ISO International Standard applied in it 13325: 2003:
In accordance with the requirements of GOST R 1.5-2004, international standards not adopted as national standards of the Russian Federation are excluded from the Regulatory Links section. The section is complemented by the following national and interstate standards: GOST 17187-81 (instead of IEC 60651: 2001), GOST 17697-72 (instead of the "Bibliography" indicated in the structural element, ISO 4209-1), GOST R 52051-2003 (instead of the specified structural element "Bibliography" ISO 3833), GOST R 41.30-99 (instead of ISO 4223-1), GOST R 41.51-2004 (instead of ISO 10844);
From subsection 6.1, information on the timing of the verification of measuring instruments is excluded, since the periodicity of calibration is established by the standards of the state system for ensuring the unity of measurements. From the same subsection, the last paragraph was excluded, since it repeats the requirements for the test site, installed in section 5;
The last phrase is excluded from A.1.7 (Appendix A). This phrase is added as a note at the end of A.1.9, at the place of the first mention of the reference speed;
From the last paragraph a.2.3 (Appendix A) the phrase is excluded "This gives the desired sound level L R.»As a duplicate first phrase of the first paragraph of the specified paragraph;
In addition, selected words changed and phrases are added, more accurately disclosing the meaning of some provisions of this standard. These changes are highlighted in text in italics.
(ISO 13325: 2003)
National Standard of the Russian Federation
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Measuring noise from tire contact Noise. Coast-by Methods for MEASUREMENT OF TYRE-TO-ROAD SOUND EMISION |
Date of introduction - 2008-07-01
1 area of \u200b\u200buse
This standard establishes the methods of measuring the noise produced by tires when interacting with the road surface when they are installed on a moving rolling vehicle (hereinafter - TC) or towed trailer, i.e. When the trailer or TC freely rolls with the engine turned off, transmission and all the auxiliary systems that are not necessary to manage TC. Insofar as noisewhen testing using the method using TCmore own tire noise, one can expect that the test method using the trailer will allow to obtain an objective assessment of its own tire noise.
This standard applies to passenger and freight. TCas they defined in GOST R 52051.. Standard is not intended to determine as a lobe of tire noise in general noise TCmoving under the action of the engine thrust and the noise level of the transport flow at a specified location point.
2. Regulatory references
This standard uses regulatory references to the following standards:
Measurements must be carried out when using frequency response BUTand temporal characteristics F.
Before starting and at the end of measurements, in accordance with the manufacturer's instruction or using a standard sound source (for example, a pistonphon), a noiseomer is calibrated, the result of which is made in the measurement protocol. The calibrator must correspond to the 1st class of software.
If the noiseomer readings obtained during calibration differ in more than 0.5 dB in the measurement series, resultstests should be considered invalid. Any deviations must be fixed in the test protocol.
Windproof screens are used in accordance with the recommendations of the microphone manufacturer.
1 - trajectory of movement; 2 - position of the microphone; BUT - BUT, IN - IN, E. - E., F. - F. - reference lines
Note - the TC movement occurs as prescribed in Appendix A, the trailer - in accordance with the Annex V.
Figure 1 - Testing and its surface
6.2. Microphones
When testing, two microphones are used, one on each side TC/ trailer. In the immediate vicinity of microphones there should be no obstacles affecting the acoustic field, and people between the microphone and the sound source. Observer or observers should be located so as not to influence the sound measurement results. The distances between the positions of microphones and the central line of movement on the test area should be equal to (7.5 ± 0.05) m. When passing the subject TC Along the midline of the movement, as shown in Figure 1, each microphone should be located at an altitude (1.2 ± 0.02) m above the surface of the test site and must be focused according to the recommendations of the noiseomer manufacturer for the conditions of the free field.
6.3. Temperature measurements
6.3.1. General provisions
Means of measurements of air temperature and the surface of the test route must have the same accuracy of at least ± 1 ° C. To measure the air temperature, infrared thermometers should not be used.
Type of temperature sensor should be specified in the test protocol.
Continuous registration can be applied through analog output. If there is no such possibility, then the discrete values \u200b\u200bdetermine temperatures.
Measuring air temperature and testing surfaces are mandatory and must be carried out in accordance with the instructions of measuring instruments. The measurement results are rounded to the nearest integer number of degrees Celsius.
Temperature measurements should accurately match the time measurement time. In both test methods (with TC and trailer) as alternative option The average value of the set of results can be used. temperature measurementsat the beginning and end of the test.
6.3.2. Air temperature
The temperature sensor is placed in a free place near the microphone, so that he can perceive the air flows, but was protected from direct solar radiation. The last requirement is provided by any shadowing screen or other similar device. In order to minimize the effect of thermal radiation of the surface on weak air flows, the temperature sensor is placed at a height of 1.0 to 1.5 m above the surface of the test site.
6.3.3. Temperature of the surface of the test site
The temperature sensor is placed in a place where it does not create interference to measure sound and its readings correspond to the temperature of the tracks of the wheels.
If a device is used in contact with a temperature sensor, then reliable thermal contact between the device and the sensor is obtained using a heat-conducting paste.
If an infrared thermometer is used (pyrometer), then height temperature Sensor Over Surfacechoose so to get a spot with a diameter of at least 0.1 m.
It is not allowed to artificially cool the surface of the test site before or during testing.
6.4. Wind speed measurements
The wind speed measurement means must provide measurement results with an error that does not exceed± 1 m / s. Wind speed measurements are carried out at the microphone height between the lines. BUT - BUT and IN - INnot further than 20 m from the midline of the movement (see Figure 1). The wind direction relative to the direction of movement is recorded in the test protocol.
6.5. Measurement speed measurements
Means of measurement speeds should ensure the results of measuring the velocity of the vehicle or the trailer with an error of no more than ± 1 km / h.
7. Meteorological conditions and background noise
7.1. Weather conditions
Measurements are not conducted under adverse weather conditions, including when the wind gusts. Tests are not carried out if the wind speed exceeds 5 m / s. Measurements are not carried out if the air temperature or test surface is below 5 ° C or air temperature above 40 ° C.
7.2. Temperature correction
Temperature correction is used only for tires C1 and C2 classes. Each measured sound level L M., dBA, corrected by the formula
L. = L M. + K.D. T.,
where L.- corrected sound level, dBA;
K. - coefficient that:
For C1 tires, C1 is minus 0.03 dBA / ° C, when the measured surface temperature of the test site is more than 20 ° C, and minus 0.06 dBA / ° C, when the measured surface temperature of the test site is less than 20 ° C;
For Class C2 tires is minus 0.02 dBA / ° C;
D. T. - The difference between the reference value of the temperature of the test site is 20 ° C and the temperature of the same surface t.during sound measurement, ° C
D. T. = (20 - t.).
7.3. Sound noise sound level
The sound level of background noise (including wind noise) must be at least 10 dBa lower than the measured sound level resulting from the interaction of the tires with the road surface. The microphone can be equipped with a windproof screen, whose influence on the sensitivity and characteristic of the microphone direction is known.
8. Tire preparation and adaptation
Test tires must be installed on the rim recommended by the tire manufacturer. The rim width must be specified in the test protocol.
Tires whose installed special requirements (hereinafter referred to as special tires) having, for example, asymmetric or directional pattern treadmust be installed in accordance with the specified requirements.
Tires and rims collected in the wheel must be balanced. Before testing tires must be running. The runoff should be equivalent to 100-kilometer mileage. Special tires Must be run in accordance with the same requirements.
Regardless of the wear of the tread, due to the bus run, the tire must have a full tread depth.
Tires of C1 and C2 classes immediately before testing should be warmed up in conditions equivalent to motion at a speed of 100 km / h for 10 minutes.
Appendix A.
(mandatory)
Method using vehicle
A.1. General provisions
A.1.1. Test vehicle
Test motor TCmust have two axes with two tested tires on each axis. TCit must be loaded to create a load on the tires in accordance with the requirements of A.1.4.
A.1.2. Wheelbase
Wheel base between the two axes of the test TC must be:
a) not more than 3.5 m for C1 tires and
b) no more than 5.0 m for C2 and C3 tires.
A.1.3. Measures to minimize influence TC For measurements
a) Requirements
1) NOT apply mudguards or other devices to protect against splashes.
2) In close proximity to tires and wheel rims, it is not allowed to install or save elements that can shield sound radiation.
3) wheel adjustment (convergence, collapse and angle of the longitudinal tilt of the swivel pivot) must be checked on empty TC and must fully comply with the manufacturer's recommendations TC.
4) Do not install additional sound-absorbing materials into wheel niches and the bottom of the body TC.
5) windows and ceiling hatch TC Must be closed during testing.
1) Elements TCwhose noise can be part of the background noise must be changed or removed. All removed S. TC Elements I. constructive changes Must be listed in the test protocol.
2) During testing, make sure that the brakes do not create a characteristic noise due to the incomplete release of the brake pads.
3) Do not use all-wheel drive four-wheeled passenger TC And trucks with reduced gearboxes on the axes.
4) The suspension state should be such that it prevents excessive decrease in clearance loaded in accordance with the requirements of the test TC. Body level control system TC relative to the surface of the road (if available) should provide the same clearance during testing, as well as the empty TC.
5) before testing TC It should be carefully cleaned of dirt, soil or sound-absorbing materials, unintentionally sticking during running.
must meet the following conditions.a) The average load on all tires must be (75 ± 5)% Li.
b) There should be no tires loaded less than 70% or more than 90% Li.
A.1.5. Tire pressure
Each tire must be pumped up to pressure (in cold tires):
where P T. - pressure in the tested bus, kPa;
P R. - Nominal pressure, which:
For standard Tire Class C1 is 250 kPa and
For the reinforced (reinforced) tire of class C1 is 290 kPa, and for the tires of both classes, the minimum pressure during testing should be P T. \u003d 150 kPa;
For tires of C2 and C3 classes, it is indicated on the sidewalls of the tire;
Q R.
A.1.6. Vehicle Movement Mode
Test TCshould approach the line BUT - BUTor IN - B. With the engine off and at the neutral position of the transmission, as accurately moving along the trajectory of the "midline of motion", as shown in Figure 1.
A.1.7. Speed \u200b\u200binterval
Test speed TCat the time of passing the microphone should be:
a) from 70 to 90 km / h for tires classes C1 and C2 and
b) from 60 to 80 km / h for C3 tires.
A.1.8. Registration of sound level
Register maximum sound levels when passing the test TCbetween lines BUT - BUT and IN - 6 in both directions.
Measurement results are recognized invalid if a too big difference is registered between the maximum and general sound levels, provided that this maximum is not reproduced at subsequent measurements at the same speed.
Note - At certain speeds, the tires of some classes may have maxima ("resonances") of the sound level.
A.1.9. Number of measurements
On each side TCperform at least four sound level measurements at the speed of the test TCabove support speed (see A.2.2) and at least four measurements at the speed of the test TC Below reference speed. Test speeds TCmust lie in the velocity interval specified in a.1.7, and should be different from support speedat approximately equal values.
Note- Support speeds are shown in A.2.2.
1/3-octave noise spectra should be measured. Time averaging must match temporary characteristic of the noisomeraF.. Noise spectra must be recorded at the moment when the sound level of the passing TC Reaches a maximum.
A.2. Data processing
A.2.1. Temperature correction
A.2.2. Support speeds
For normalization of noise relative to the speed, the following supporting speeds are used v ref:
80 km / h for C1 or C2 tires and
70 km / h for C3 tires.
A.2.3. Regulation relative to speed
Say Test Result - Sound Level L R. - get by calculating the regression line relative to all pairs of measured values \u200b\u200b(speed v I.Corrected by sound level temperature L I.) according to the formula
L. r \u003d `. L. - a ·`v.,
where ` L. - the medium-generic value corrected by temperature levels, dBA;
Where the number of terms p ³ 16 When using measurement results performed for both microphones, for this regression line;
the average speed of where
but - the tilt of the regression direct, dBA for a decade of speed,
Additionally sound level L V.for arbitrary speed v (from the consideredspeed \u200b\u200bintervals) can be determined by the formula
A.3. Test report
The test protocol must contain the following information:
b) meteorological conditions, including air temperature and test track surface for each pass;
c) the date and method for checking the compliance of the test section of the test section with the requirements of GOST R 41.51;
d) the width of the test wheel of the wheel;
e) tire details, including manufacturer name, trade name, size, Li or load capacity, speed category, nominal pressure and factory tire number;
f) manufacturer name and type (group) test TC, year model TC and information about any modifications ( constructive changes) TC Regarding sound;
g) tire load in kilograms and in percent Li for each tire test;
h) air pressure in a cold tire for each tested tire in kilopascals (kPa);
i) test speed TC past microphone;
j) maximum sound levels for each microphone for each passage;
k) The maximum sound level, dBA normalized to the reference speed and adjusted by temperature, expressed with an accuracy of one decimal sign.
Tables A.1, A.2 and A.3 show respectively form of representation necessary information For testing protocol, data test conditions of methods as using TCand using the trailer, and test results TC.
Table A.1 - Test Protocol
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Road tests of tires on noise in accordance with GOST R 52800-2007 (ISO 13325: 2003) |
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Test Protocol No.: _________________________________________________________________ |
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Tire details (trademark, model name, manufacturer): |
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__________________________________________________________________________________________ __________________________________________________________________________________________ |
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Tire manufacturer address: _____________________________________________________________ __________________________________________________________________________________________ |
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Tire size: _____________ |
Factory tire number: _________________ |
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Nominal pressure: ____________________________ |
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Tire class: (Mark one point) |
□ passenger passenger TC (C1) |
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□ freight TC (C2) |
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□ freight TC (C3) |
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Annexes to this Protocol: ____________________________________________________________ __________________________________________________________________________________________ |
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The stated sound level: ____________ DBA |
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with support speed: |
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Comments (at other speeds) _________________________________________________________ |
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Responsible for testing: _____________________________________________________ |
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Name and address of the applicant: _____________________________________________________________ __________________________________________________________________________________________ |
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Date of compilation of the Protocol: ______________________________ Signature: |
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Table A.2 - Additional data / information regarding tire tests for noise
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Table A.3 - Test Results for Motor Vehicle
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Test number |
Speed, km / h |
Direction of motion |
Sound level (without temperature correction) on the left side, dBA |
Sound level (without temperature correction) on the right side, dBA |
Air temperature, ° C |
Surface Temperature, ° C |
Sound level (with temperature correction) on the left side, dba |
Sound level (with temperature correction) on the right side, dBA |
Notes |
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The stated sound level _________ dBA |
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Note - The stated sound level value must be calculated at the support speed as a result of regression analysis after temperature correction and rounding to the nearest integer value. |
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Appendix B.
(mandatory)
Trailer use method
B.1. Traction vehicle and trailer
B.1.1. General provisions
The test complex should consist of two parts: traction TC and trailer.
B.1.1.1. Traction vehicle
B.1.1.1.1. Sound level
Sound of movement of traction TC Must be maximally reduced by applying appropriate measures (installation of low noise tires, screens, aerodynamic fairings, etc.). Ideally, the sound level traction TC. must be at least 10 dBA below the total sound level traction TC. and trailer. However, there is no need to carry out multiple measurements with traction TC. It is possible to increase the accuracy of measurements due to the lack of subtraction of the sound level of the traction TC. The required levels of levels and the calculated sound level of the tire are given in V.4.
should not change during test passages of traction TC with a trailer. To ensure a stable load during testing traction TC If necessary, load ballast.B.1.1.2. Trailer
B.1.1.2.1. Uniaxial frame trailer
The trailer must be a uniaxial frame trailer with coupling device and a device for changing the load on the tires. Tires must be tested without wings or wheeled housings.
B.1.1.2.2. Coupling length
The length of the coupling device measured from the center of the traction TC to the axis of the trailer, should be at least 5 m.
B.1.1.2.3. Width of the King
The horizontal distance measured perpendicular to the direction of movement between the middle of the contact spots of the trailer tires with the surface of the road should not exceed 2.5 m.
B.1.1.2.4. Collapse and convergence
The corners of the collapse and convergence of all tested tes under test conditions should be zero. The error for the collapse should be ± 30 "and for an angle of ± 5".
B.2.
For tires of all classes, the test load should be (75 ± 2)% of the nominal load Q R.
B.2.2. Tire pressure
Each tire must be pumped up to pressure (in cold tires)
where P T. - test pressure, kPa;
P R. - Nominal pressure, which is equal:
250 kPa for standard tires class C1;
290 kPa for Class C1 reinforced tires;
Specified on the sidewall value of pressure for tire classes C2 and C3;
Q R. - maximum load mass corresponding to Li tires;
B.3. Measurement method
B.3.1. General provisions
When conducting tests of this species, two measurement groups must be performed.
a) first test traction TC and register the measured sound levels in accordance with the method described below.
b) then conduct tests traction TC. Together with the trailer and register the total sound levels.
The audio level of the tires is calculated according to the method described in B.4.
B.3.2. Location of vehicle
Traction TC or traction TC together with the trailer should approach the line E. - E. with (muffled) engine at neutral speed with clutch off; middle line TC Must as much as possible with the central line of movement, as shown in Figure B.1.
B.3.3. Motion speed
Before entering the test zone ( E. - E. or F. - F,see Figure B.1) Traction TC It should be dispersed to a certain speed, so that the average speed of inertia TC With the engine off, together with the trailer between the lines A. - A. and IN - INthe test site was equal to (80 ± 1.0) km / h for tires of classes C1 and C2 and (70 ± 1.0) km / h for C3 tires.
B.3.4. Necessary measurements
B.3.4.1. Noise measurements
Register the maximum values \u200b\u200bof sound levels measured during the passage of tested tires between the lines A. - A. and B. - B. Testing tracks (see Figure B.1). Additionally, when the measurement zone passes, you must register the sound level values \u200b\u200bfor each microphone at a time intervals that do not exceed 0.01 s using the integration time equivalent to the time characteristic. F. Noiseomer. This data as a dependence of sound levels from time is needed for subsequent processing.
1 - trajectory of movement; 2 - reading point TC; 3 - position of the microphone; A. - A. and A " - A ", B. - B. and B " - B ", E. - E. and E " - E ", F. - F. and F " - F ", O. - O. and O " - O " - reference lines
Figure B.1 - Diagram of the test site and the location of the TC with the trailer to register the dependence of the sound level of tires from time
Measurement of the level of sound level from time starts with definition of lines A " - A " and B " - B "As shown in Figure B.1. These lines are determined by proactive distanced T. from axles of wheel trailerto the counting point of traction TC (see Figure B.1.). The reading point is a point. TCwhen crossing which lines A " - A " and B " - B " celebrate beginning and the endtime of registration sound.When passing as TC with a trailer and solitary traction TC Apply the same registration methodology sound level.
B.3.4.2. Additional measurements
During each passage, the following information is recorded:
a) ambient temperature;
b) the surface temperature of the track;
c) does not exceed the wind speed 5 m / s (yes / no);
d) whether the difference in the sound levels of the measured and background noise 10 dBA and more (yes / no);
e) the average traction rate TC Between lines A. - A. and B. - B..
B.3.5. Medium sound levels
Register changes in time of sound levels and the maximum level achieved during each passage for each microphone. The measurements continue until the five maximum sound levels recorded for each speed and for each microphone position will differ by more than ± 0.5 dBA from their average values \u200b\u200bwithout temperature correction. In accordance with 7.2, these average maximum levels and averaged time dependences should be adjusted by temperature. Then averaging the temperature-corrected values \u200b\u200bobtained for both microphones to determine the sound levels averaged over microphones and time dependence. Next, calculate the arithmetic average of two sound levels averaged over microphones for traction TC. Single and together with a trailer and write down the average sound level of the passage. Apply the same averaging technique for the level of sound level from time. In subsequent calculations use the above-mentioned values \u200b\u200bof the sound level dependences from time to time:
`L. T - average of maximum sound levels traction TC without trailer;
L. T (T) - the average value of the time dependency levels of sound traction TC without trailer;
`L. TP - the average value of the maximum sound levels in the test pass (traction TC together with the trailer);
L. T p (t) - the average value of the time dependency level of sound levels in the test pass (traction TC Together with the trailer).
B..3.6. Synchronization of temporary dependency records
When crossing traction TC lines ABOUT" - ABOUT" Together with the sound level, you must register a synchronizing pulse. This pulse should be used to accurately align the time signals in averaging and subtraction. levels.
B.3.7. Test Methods
The method of conducting tests with a trailer is to perform the following steps.
a) Preparation
1) Set the reading point on the towing TC for time synchronization.
2) Measure d T. (see Figure B.1).
3) define the position of lines E " - E ", A " - A ", ABOUT" - ABOUT", B " - B " and F " - F " On the test site of the track, as shown in Figure B.1. Install recording synchronization devices so that the sound level recording began on the line E " - E " and ended on the line F " - F ".
4) average speed Movements between lines A. - A. and B. - B. It should be equal to (80 ± 1.0) km / h for tires classes C1 and C2 and (70 ± 1.0) km / h for the C3 tires. Speed \u200b\u200bis measured on a plot from A. - A. before B. - B.which is for a tuning time sensor on towing Ts Equivalent to the plot OT A " - A "before B " - B ".
5) Install the data recorder in such a way that the recording of sound levels sequential in time was carried out on the plot from the lines E " - E " to lines F " - F " both in single and in a joint trial. Set the synchronization sensor time sequences of sound levels relative to the line ABOUT" - ABOUT" In accordance with B.3.6.
6) Check devices for measuring air temperature and wind speed.
b) Single test (traction vehicle without trailer) at least five passes
1) register the maximum sound level and change in time of the sound level in each passage and for each position of the microphone. These measurements continue until the maximum sound level at each measurement point is different from more than ± 0.5 dBA from their average value.
4) Perform steps from 1) to 3) from the beginning to the end of each test series. Test traction TC Every time the air temperature changes at 5 ° C and more.
c) joint test (trailer trailer) at least five passes
1) register the maximum sound level and change in time of the sound level in each passage and for each position of the microphone. These measurements continue until the maximum sound level is different than ± 0.5 dBA from their average value at each measurement point.
2) conduct a temperature correction of five dependences of sound levels from time and maximum sound levels within ± 0.5 dBA from their average value.
3) For these five dependences, sound levels from time to time calculate the average sound level.
See Tables B.1 and B.2.
AT 4. Definition of tire sound levels
V4.1. Accounting for the effect of the noise of the traction vehicle
Before determining the noise level of tires when moving in rolling, you must ensure the possibility of appropriate calculations. To properly calculate the noise level of tires should be a sufficient difference between sound levels measured for solitary TC, and sound levels TC with a trailer. This difference can be checked in two ways.
a) The difference of maximum sound levels of at least 10 dBA
If for both measurement points, the difference between the average sound levels TC Together with the trailer and the average value of the maximum sound levels of single traction TC It is at least 10 dBs, effective measurements can be carried out. At the same time, it is believed that all other requirements are made regarding external conditions, background noise, etc. In this special case, the noise level of the tire is equal to the average maximum level measured for TC Together with the trailer:
L. Tyre \u003d. `L. T p,
where L. TYRE - The sound level of the tire itself (i.e. the value to be determined), dBA.
b) the difference of maximum sound levels less than 10 dBA
If the difference between the average sound levels TC Together with the trailer and the average value of the maximum sound levels of single traction TC For both or one point of measurements less than 10 dBA, further calculations are needed. These calculations use corrected averages of sound levels dependences from time.
V.4.2. Calculations based on the dependences of sound levels from time
Definition sound level Tire is a difference between the averaged sound levels. TC with a trailer and solitary traction TC. To calculate this difference, the temperature corrected average value of the level of sound level is deducted from a similar value for TC with a trailer. The average of five aisles of sound levels in which the maximum sound levels differ in less than ± 0.5 dBA are calculated as described above. An example of the dependence of sound levels from time is shown in Figure B.2.
1 - traction TC; 2 - TC with trailer
Figure B.2 - Dependence of sound levels from time when driving rolled for test method using trailer
After bringing dependencies to time to the beginning of the reference relative to the line ABOUT" - ABOUT", the main parameter for the analysis is the difference between the average level dependence on the traction TC Together with the trailer and the average dependence of the level of singles TC At the same point. This difference level L. Tr - L. T is shown in Figure B.2.
If this difference is at least 10 dBA, then levels measured for traction TC with a trailer represent reliable values \u200b\u200bfor the tested tire; If this difference is less than 10 dBA, the tire sound level is calculated by the logarithmic subtraction of the sound level value for solitary TC From the value for TC Together with the trailer, as shown below. The logarithmic difference is expressed in the above and shown in Figure B.2 The average values \u200b\u200bof time dependences. Sound level to be determined L. TYRE, DBA, calculated by the formula
where L. T p - maximum sound level, dBA for test pass ( TC together with the trailer);
L. T - the sound level of the traction TC without trailer, dBA, obtained for the same position TCthat I. L. T p.
B.4.3. Sound level method
If the average value of the maximum sound levels for traction TC with a trailer for the right and left microphones exceeds the equivalent level for solitary TC not less than 10 dBA, the tire sound level is equal to the level of sound TC With a trailer (the results of the calculations are shown in Table V.5) and, therefore, the procedures for the following transfers A), b) and C) are not performed. However, if this difference is less than 10 dBA, then the following procedures perform:
a) Combine start recordingthe dependences of sound levels from time for solitary TC and TC Together with the trailer and determine the arithmetic difference levels for each time increment. Register this difference of sound levels at a level maximum point for TC with a trailer. Repeat this action for each set of test passages.
If the registered difference exceeds 10 dBA, then tire sound levels are equal to sound levels TC with a trailer.
b) if the calculated difference is less than 10 dBA and more than 3 dBA, then the sound of the tire sound is defined as a logarithmic difference between the maximum value of the level dependence of the sound level from time for traction TC With the trailer and the average value of the level of sound level from the time of singles TC At the time of time corresponding to the maximum sound level for TC with a trailer.
c) If the calculated difference is less than 3 dBA, the test results are recognized as unsatisfactory. Sound level TC It should be reduced to such a value so that the specified difference has become more than 3 dBA, which is necessary to correctly calculate the value of the tire sound level.
See Tables B.1 and B.2.
B.5. Test report
Test protocol must include the following information:
b) meteorological conditions, including air temperature and test surface for each passage;
(c) An indication of when and how the testing of the test site for compliance with the requirements of GOST R 41.51 was carried out;
d) the width of the tested tire rim;
e) tire data, including the name of the manufacturer, trademark, trade name, size, Li or load capacity, speed category, nominal pressure and factory tire number;
f) Type and Test Group TC, year model and modifications information (constructive changes) TC relative to its noise characteristics;
(g) Description of test devices with a specific indication of the length of the coupling device, the data of collapse and convergence during test load;
(h) Tire load in kilograms and in percent Li for each tire test;
i) air pressure in kilopascals (kPa) for each tire test (in cold condition);
j) the speed with which TC moving by a microphone with each pass;
k) the maximum value of the sound levels at each passage pass for each microphone;
l) the maximum sound level, dubbing normalized to the support speed and adjusted by temperature with an accuracy of one decimal sign.
Tables in B.1 and B.2 are the forms of the protocol of test results and registration of additional data regarding tire noise tests. Tables B.3, V.4, V.5, V.6 and V.7, respectively, are examples of registration of test results of traction TC, TC With a trailer, checking the suitability of test results, checking the calculations for time, the difference in the sound level and calculating the tire sound level.
Table B.1 - Test Protocol
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Test to determine the noise level from contact tires with a road surface when moving in rolling in accordance with GOST R 52800-2007 (ISO 13325: 2003) |
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Test Protocol Number: ________________________________________________________________ |
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These tires (trademark, trading sign, manufacturer): ___________________________________ __________________________________________________________________________________________ |
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Manufacturer data for commercial use of tires: _____________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ |
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Address of the manufacturer: _______________________________________________________ __________________________________________________________________________________________ |
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Tire size: _______________________________ factory number ___________________________________ |
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Nominal pressure: ___________________ |
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Tire class: (Mark one point) |
□ Easy passenger car (C1) |
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□ truck (C2) |
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□ truck (C3) |
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Annexes to this Protocol: _____________________________________________________ __________________________________________________________________________________________ |
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DBA sound level at support speed: |
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COURSE WORK
on the topic: "Study of the noise level in the area of \u200b\u200binfluence of roads"
Introduction
1 Chapter. Motor transport as a source of noise.
2 Chapter. Calculation of noise level in the area of \u200b\u200broad influence on the example of victory prospectus.
Conclusion.
List of used literature.
Appendix number 1.
Appendix number 2.
Introduction
Transportation is one of the most important components of public and economic development, absorbing a significant amount of resources and has a serious impact on the environment.
Automobile transport played a huge role in the formation of the modern nature of the settlement of people, in the distribution of long-range tourism, in the territorial decentralization of industry and service sector. At the same time, he also caused many negative phenomena: hundreds of millions of tons come to the atmosphere each year with speaking gases in the atmosphere harmful substances; The car is one of the main factors of noise pollution; Road network, especially near urban agglomerations, "eats" valuable agricultural land. Under the influence of the harmful effects of road transport, the health of people deteriorates, soils and reservoirs are poisoned, the floral and animal world suffers.
Nowadays, the impact of transport, but the environment is the most pressing and actual problem of modern society. The consequences of this impact affect not only our generation, but also may affect the future generation, if we do not take serious measures to reduce and even eliminate the effects of impact and impact.
Therefore, my goal term paper It is to show the effects of the transport and road complex on the environment, the consequences and measures to combat them.
The tasks of my course work are:
· Consideration of the impact of road transport on the environment.
· Consideration of the consequences of the effect of transport on the OS.
1 CHAPTER. Motor transport as a source of noise.
Noise - Disorder fluctuations in various physical nature, characterized by the complexity of the temporary and spectral structure.
One of the main sources of noise in the city - automobile transport, whose motion intensity is constantly growing. The highest levels of noise 90 - 95 dB are celebrated on the main streets of cities with an average intensity of motion of 2-3 thousand and more transport units per hour.
The level of street noise is caused by intensity, speed and character (composition) of the transport flow. In addition, it depends on the planning solutions (longitudinal and transverse street profile, height and density of development) and such elements of improvement, as covering the carriageway and the presence of green plantings. Each of these factors can change the level of transport noise within up to 10 dB.
The noise arising from the roadway of the highway is applied not only for the primary territory, but also deep into the residential building. Thus, in the zone of the most powerful impact of noise there are parts of quarters and microdistricons located along the highways of a citywide value (equivalent noise levels from 67.4 to 76.8 dB). Noise levels measured in residential rooms with open windows focused on the indicated highways, only 10-15 dB below.
The acoustic characteristics of the transport stream is determined by the indicators of the noise of the traffic. The noise produced by individual transport crews depends on many factors: the power and mode of operation of the engine, the technical condition of the crew, the quality of the road surface, the speed of movement. In addition, noise level, as well as the efficiency of the car, depends on the driver's qualifications. The noise from the engine increases sharply at the time of its launch and warming up (up to 10 dB). The movement of the car in the first speed (up to 40 km / h) causes an excessive fuel consumption, while the engine noise is 2 times higher than the noise created by it at the second speed.
Significant noise causes a sharp braking of the car when driving at high speed. The noise decreases markedly if the speed of movement is quenched by the engine braking until the foot brake is turned on.
Recently, the average noise produced by transport increased by 12-14 dB. That is why the problem of combating noise in the city is becoming increasingly sharp.
Measuring noise level and existing rules.
The interaction of the tire and the road produces noise that is perceived at varying degrees inside and outside the car.
From point of view ambient Of interest is caused by noise outside the car, which can be determined by:
1. Measurement of the general noise indicator
2. Measuring noise from the movement of a separate car.
The overall noise indicator is a permanent noise level for a certain period of time, which is a result from the actual noise allocation process.
There are several main methods for measuring noise when the car is moving, but none of these methods are not yet standardized.
Car manufacturers measure overall noise levels when accelerating the vehicle's movement by various tests.
Motor noise measurements are needed to approve the type of car, since this requires european standard To access the automotive industry to the European market and brutal competition in the industry.
Tire producers measure the noise level from the contact of the tire and the surface of the road for its purposes, checking the general performance features Tires under different conditions.
Road builders determine the acoustic properties of road surface surfaces, but by their methods that do not give comparable results, which could be linked to the noise produced by a moving vehicle (taking into account the type of tire and engine operation).
Thus, within the framework of these three groups, the results expressed in physical units - decibels (dB) cannot be used in one common mathematical model that could be the basis for decision making.
Vehicle.
Until now, to assess the noise produced by such a source as a vehicle, a too generalized approach was used.
In fact, this common noise can be decomposed between two main sources:
1. traction energy vehicle (engine, cardan Val., gears),
2. Contact Tires and Coatings.
W. last models Heavy vehicles dominant part of the total noise is noise from the contact of the tire and coating. Since the 60s, manufacturers of truck engines have achieved a decrease of 15 times the noise of traction energy by introducing project improvements.
However, if the overall noise of the motor vehicle is determined by standardized methods, then the standard that would suit for measuring the noise of the contact of the tire and coating the road as a part of the total noise, does not yet exist.
Interaction Tire - Road.
The contact of the moving tire and coating produces a whole spectrum of sound waves, more or less distinguishable originating due to the rolling effect of the wheel. Knowledge of the mechanism of the occurrence and distribution of these sound waves reduces the degree of their environmental impact.
Special noise measurement methods have been developed for a combination: a car cover-coating.
The components of noise sources have been identified and the effect of each of them is studied on various parameters involved in the generation and distribution of noise.
Reducing the level of rolling noise is to control the processes of its generation, distribution and absorption, which depend:
· From vehicle (weight, wheel number, vibration, body forms),
· From a tire (pressure / propagation of air under the surface of the tread, its drawing, the contact area and the clutch of the surface of the tire with the surface of the road),
· From the rolling condition (speed, torque, ambient temperature),
· From the road (surface characteristics of the coating, road clothing design, transverse profile).
When studying different noise levels from contact, the tire / coating is revealed that rolling noise:
· Significantly increases with increasing speed (3 dB + 0.2 / 0.5 dB for every 15 km / h),
· When moving at a constant speed of about 60 km / hour, the noise of rolling dominates the engine noise,
· When measured on the border of the coating varies from 3 dB, depending on whether smooth tires or medium (European types) tread tires are used,
· When measuring on the surface of the tire, the noise varies from 6 dB, depending on the design characteristics of the road (measurements were carried out on typical European main roads).
To limit noise, it is required to study the complex contact model Tire / coating, taking into account the characteristics of the coating and tires.
The effect of noise per person.
Depending on the level and nature of noise, its duration, as well as from the individual characteristics of a person, the noise can have various actions on it.
According to certificates of doctors, constant noise affects the work of many vital organs: heart, liver, digestive organs. But first of all suffers, of course, rumor. Therefore, among employees of enterprises, where the prolonged impact of noise is, as it were, an integral part of the production process, there are its own statistics of occupational diseases to which neurosensory touginess belongs. First of all, the ability to hear the drivers of heavy special equipment to hear the ability to hear risks drivers. And it is clear why: throughout almost the entire shift (and it can last 8, and 10, and 12 hours) they work under a deafening accompaniment of engines. But, for example, the compressor unit operator does not contact the "noisy" equipment, and hence he, therefore, the risk of the disease is less.
Noise, even when he is small, creates a significant burden on the human nervous system, having a psychological impact on him. This is especially often observed in human mental activities. Weak noise affects people. The reason for this may be: age, state of health, type of labor. The impact of noise depends on the individual attitude towards it. So, the noise produced by the person himself does not bother him, while a small extraneous noise can cause a strong irritating effect.
The absence of the necessary silence, especially at night, leads to premature fatigue. High level noises can appear good soil for the development of insomnia, neuroses and atherosclerosis.
Under the influence of noise from 85 - 90 dB, the hearing sensitivity at high frequencies is reduced. For a long time, people complain about malaise. Symptoms - headache, dizziness, nausea, excessive irritability. All this is the result of work in noisy conditions.
The effect of noise per person has not been the object of special studies until some. Nowadays the impact of sound, noise on the function of the body studies the whole branch of science - Audiology. It was found that noise of natural origin (the noise of the sea surf, foliage, rain, the murmur of the stream and others) have a beneficial effect on the human body, soothe it, the healing dream is visible.
Among the senses are hearing, one of the most important. Thanks to him, we are able to analyze all the variety of sounds surrounding us the external environment. The rumor is always awake, to a certain extent even at night, in a dream. It is constantly irritating for no protective equipment similar, for example, with centuries that protect eyes from light.
Ear - one of the most complex and delicate organs he perceives and very weak, and very strong sounds.
Under the influence of strong noise, especially high-frequency, irreversible changes occur in the organ of hearing.
With high noise levels, the hearing sensitivity drops after 1 to 2 years, with medium - it is found much later, after 5-10 years, that is, the reduction of hearing occurs slowly, the disease develops gradually. Therefore, it is especially important to take appropriate measures to protect against noise. Currently, almost every person exposed to the effects of noise risks to become deaf.
Even the weak sounds of infrasound can have a significant impact on humans, especially if they are long. According to scientists, it is infrasounds, which are sneakingly penetrate through the thick walls, many nervous diseases of the inhabitants of large cities are caused.
Ultrasound, occupying a noticeable place in the range of production noise, is also dangerous. The mechanisms of their action on living organisms are extremely diverse. The cells of the nervous system are particularly negatively exposed to their negative effects.
The noise is cunning, its harmful effects on the body is committed invisibly, imperceptibly. Disorders in the human body against noise almost defenseless.
Currently, doctors talk about the noise disease developing as a result of the effects of noise with a preferably leaning of hearing and nervous system.
The noise pollution in the cities is almost always local and mainly caused by means of transport - urban, railway, the concentration of which is great and in Veliky Novgorod. Already on the main highways noise levels exceed 90 dB and tend to strengthen annually by 0.5 dB, which is the greatest environmental hazard in areas of lively transport highways. According to medical studies, elevated levels of noise contribute to the development of neuropsychiatric diseases and hypertension. The fight against noise, in the central regions of cities is hampered by the density of the current development, due to which the construction of noise protection screens is impossible, expanding highways and landing of trees that reduce noise levels on roads. Thus, the most promising solutions of this problem are to reduce their own noise of vehicles (especially tram) and use in buildings overlooking the most lively highways, new noise absorbing materials, vertical landscaping of houses and triple glazing windows (with the simultaneous use of forced ventilation).
The special problem is an increase in the level of vibration in urban areas, the main source of what is transport. This problem is little studied, but it is undoubted that its value will increase. Vibration contributes to more rapid wear and destruction of buildings and structures, but the most significant thing is that it can adversely affect the most accurate technological processes. It is especially important to emphasize that the greatest damage vibration brings to advanced industries and, accordingly, its growth may have a limiting impact on the possibilities of scientific and technological progress in cities.
The acoustic irritation is urged, like the poison, accumulate in the body, is still stronger than the boring nervous system. The force, equilibrium and mobility of nerve processes changes, especially as more intense noise. The response to noise is often expressed in increased excitability and irritability covering the entire sphere of sensual perceptions. People exposed to the constant influence of noise often become difficult to communicate.
So, the noise has its destructive effect on the entire human body. His disastrous work contributes to the fact that we are almost defenseless against noise. Dazzling bright light makes us instinctively closed. The same self-preservation instinct saves us from the burn, reducing the hand from the fire or from the hot surface. But on the impact of the noise of the protective reaction in humans.
Permissible noise levels for the population.
To protect people from the harmful influence of urban noise, it is necessary to regulate its intensity, spectral composition, time of action and other parameters. In hygienic rationing, such a noise level is established as permissible, the influence of which for a long time does not cause changes in the entire complex of physiological indicators, reflecting the reactions of the most sensitive to the noise of the body systems.
The basis of hygienically permissible noise levels for the population are fundamental physiological studies on the definition of existing and threshold noise levels. Currently, noises for the conditions of urban development are normalized in accordance with the sanitary standards of permissible noise in the premises of residential and public buildings and on the territory of residential building (No. 3077-84) and construction regulations and regulations II. 12-77 "Noise Protection". Sanitary standards are required for all ministries, departments and organizations designing, building and operating housing and public buildings, developing projects for planning and building cities, microdistricts, residential buildings, quarters, communications, etc., as well as for organizations that are designing manufacturing and operating vehicles, technological and engineering equipment of buildings and household appliances. These organizations are required to provide and implement the necessary measures to reduce noise to the levels established by the norms.
One of the directions of the fight against noise is the development of state standards for means of movement, engineering equipment, household appliances, which are based on hygienic requirements for the provision of acoustic comfort.
GOST 19358-85 "External and internal noise motor vehicles. Valid levels and measurement methods "Sets noise characteristics, measurement methods and permissible levels of car noise (motorcycles) of all samples adopted on state, interdepartmental, departmental and periodic control tests. As the main characteristic of external noise, the level of sound that should not exceed for passenger cars And buses 85-92 dB, motorcycles - 80-86 dB. For internal noise, the approximate values \u200b\u200bof permissible sound pressure levels are given in octave frequency bands: sound levels are for passenger cars 80 dB, cabins or workplaces of truck drivers, buses - 85 dB, passenger premises of buses - 75-80 dB.
The sanitary standards of permissible noise determine the need to develop technical, architectural and planning and administrative activities aimed at creating the hygienic requirements of the noise regime, both in urban development and in buildings of various purposes, allow to preserve the health and performance of the population.
The movement of the car on the road canvase is not silent, due to the simplest laws of physics. Although summer tires Compared to winter, it creates less noise when contacting the wheels of the car with a road surface, however, and they provide an unpleasant sound background. Therefore, today, along with the parameters of the effects of resistance to the aquaplating and braking on a wet road for consumers, when the tire is selected, the noise factor becomes particular importance. Of course, the noise noise level is largely determined from the surface at which movement is carried out, as well as on the pressure in the rubber. If the road surface is inhomogeneous or the level of tire pressure is less than recommended, it is obvious that noise will increase significantly. However, much depends on the composition of the rubber mixture, the tread pattern and the width of the autoresine. In particular, tires made using soft rubber mixtures and possessing a relatively small stain of contact with the road fabric, no less noise. The reduced noise level ensures the smoothness of the movement and makes the control of the car more comfortable for the driver.
Despite the growing needs of consumers in reducing the autoresine noise produced, tire manufacturers activate work in this direction also for another reason. The fact is that many environmental organizations and individual states in recent years have seriously affected the problem of excessive noise on automotive tracks. For example, the European Federation for Transport and Environment (European Federation for Transport and Environment) suggested that the EU officials have suggested that it can be done to reduce the noise from road transport. According to this authoritative organization, a significant part of the noise on the road routes is not from the engine of the car, but from rubber, which is constantly in contact with the surface of the road. Already at speeds over 30 km / h for cars and 50 km / h for trucks noise from tires exceeds the noise of their engines. Given that in recent years, the demand for wide tires is increasing, this problem is becoming increasingly relevant. That is why it is expected that in the new standards of the European Commission, which should be taken into force on November 1, 2011, in addition to the clutch requirements on the wet surface and tire marking, there will be regulations by noise level. Such a state of affairs forces world manufacturers of autoresin to develop new tire models with a reduced level of noise.
How can I reduce the noise level published by the tire when contacting the road surface? The noise level is influenced by such tire parameters as a tread pattern, the design of spikes and lamellae, and the features of the rubber mixture. Each time a collision of a separate tread tread unit, the noise of a certain frequency is created, and if all blocks are the same size, the noises of the identical frequency will be created, which, in turn, leads to an increase in the overall noise level. Therefore, many manufacturers use blocks of various sizes in separate parts of the tread, due to which tire noise is distributed in a wider frequency range. Similar constructive features Autoresin allow us to reduce the overall level of noise.
Determine the level of noise and, accordingly, driving comfort helps special tire tests. As a rule, they are held together with braking tests for dry and wet surface, resistance to aquaplaning and other tests. The measurement of the noise bus is determined in the decibels, on the right and to the left of the moving car. This also registers the speed of the vehicle.
We offer your attention tests of summer tires of dimension 205/55 R16, conducted by experts of the authoritative magazine "driving". In traditional tested rubber, in addition to tests on the car handling on dry and wet asphaltThe course stability for a straight line, fuel consumption and smoothness of the stroke were tested and for the noise level of summer tires. Eleven summer tires participated in tests: Pirelli P7, Michelin Energy Saver, Nokian Hakka. H, Yokohama C. Drive AC01, Maxxis Victra Ma-Z1, Goodyear Excellence, Kumho Ecsta HM, Bridgestone Potenza Re001 Adrenalin, Continental ContipremiUmcontact 2, Toyo proxes. CF-1 and Vredestein Sportrac 3. The journal experts estimated tire noise as other indicators on a ten-billion system.
The lowest estimate in the tests on the noise level was obtained by South Korean tires Kumho. ECSTA HM - only six of ten. Such a low estimate is due to the fact that the tire tests showed a very serious common hum of the tread, the speed of up to 80 km / h, the truth, practically disappearing at a higher speed. Taking on the level of noise Last, eleventh place, the summer tires Kumho Ecsta Hm, however, for the aggregate of all parameters, some competitors could bypass and take the overall eighth place.
Some summer tires immediately received from experts from the journal an average estimate Seven out of ten. In particular, the Tires Maxxis Victra Ma-Z1, which took the last eleventh place in tests due to increased flow Fuel at any speed and sharp shocks during the passage of single irregularities, also distinguished themselves with an increased background hum. This did not interfere with even the original pattern of tire tires Maxxis Victra Ma-Z1 type "Flame". Summer tires Yokohama C. Drive AC01 When the direction of movement is changed, reinforcing sound. At a speed of 120 km / h and above clapper on the seams and other irregularities, despite the use of Micro Flexible Compound in these tires, which, according to developers, should provide a minimum noise level. Therefore, the journal experts set tires Yokohama. C. Drive AC01 Evaluation Seven out of ten. Such an assessment deserved and high-speed summer tires with asymmetric pattern Tread Potenza Re001 Adrenalin. On single irregularities, they sharply pushed the car, thumps on the transverse seams and make the appropriate background hum. Summer autoresina Continental ContipRemiumContact 2, which is characterized by a three-dimensional groove with steep and flat edges, in tests on the noise level also showed itself very medium. The background noise of these tires is increased, especially on coarse-grained asphalt. According to a good road, the Continental ContiPremiUmcontact 2 bus allow you to roll comfortably, but medium and large irregularities pass hard, making an unpleasant hum. As a result, score - seven out of ten. Summer michelin tires Energy Saver, which differs in an increased economy at any speed, displaced the change in the grain of asphalt. On dry asphalt, they caused small complaints of noise from the journal experts, for which they received an estimate of seven points. The Summer Tires of Vredestein Sportrac 3, which have become the best in testing tests and handling, in tests for noise levels also evaluated only seven points. Experts embarrassed unpleasant background hum, providing an insufficient level of comfort.
Four tire brands received from experts of the journal "driving" on eight points were the best in terms of noise. This is summer goodyear tires Excellence, the design of which includes a double-step block sequence, which provides a reduced level of noise. According to the test results rubber Goodyear. Excellence showed a low noise level and high smoothness. High evaluation of experts also deserved tires Pirelli. P7 with asymmetric tread pattern. Despite big flow fuel, these tires are different increased level Comfort. Non-traditionally quiet, they only slightly voiced the irregularities of the road surface. Finnish summer tires nokian. Hakka H, \u200b\u200bwho took the results of common tests of the honorable, third place, showed good level Comfort. Silent, comfortable tires, on the "pedestrian" speed up to 10 km / h, slightly transmit to the body to jolts from road irregularities. But if you go faster, they become softer and better rolling, almost without any noise. Estimation - eight out of ten. Finally, summer toyo tires Proxes CF-1, who came to the change of the popular model of Toyo Proxes R610, are distinguished by high acoustic comfort, which has shown during testing at noise level. After taking the final second place in terms of indicators, Toyo Proxes CF-1 tires distinguished themselves high level of comfort and low noise levels. Using cheats and codes for GTA, you can turn the game into solid pleasure
As evidenced by tests, summer tires that showed best results such important characteristicsAs manageability on the wet and dry coating, resistance to aquaplaning and course stability, may differ in high levels of noise (Vredestein Sportrac 3). While, autoresina with not the best performance and braking indicators can earn the highest noise ratings (Goodyear Excellence). It tells us that when choosing summer rubber It is necessary to navigate non-one specific characteristic, but to a whole set of indicators that include the behavior of the tires on the wet and dry road surface, exchange resistance, resistance to aquaplaning, the level of acoustic comfort and smoothness.
In connection with the next rules entered into force in the European Union in November 2012, the label indicating three main indicators: the degree of adhesion with wet and dry road coating, fuel consumption and noise levels. Many domestic manufacturers Tires followed this example and also these parameters, on the basis of which the consumer determines its preference for a particular brand and, accordingly, the models automotive tires.
Noise levels
Noise level automotive rubber The label is indicated in the form of a pictogram, which consists of three waves.
The noise level of 3 decibels means that the tire that makes the sound of 3 decibels more than another - twice as no matter. Where it follows that rubber marked with three waves noise is at least four times than rubber having one wave.
The noise of automotive tires depends largely on the type of road surface and its roughness, level, as well as from the composition of the rubber mixture and the width of the wheel.
Tires manufactured using soft rubber mixtures and having a relatively small area of \u200b\u200bcontact with the road canvase, are no less noise.
The noise level significantly affects the design of the lamellae and the presence of spikes. When a collision of a separate protector block with a road canal, sounds (noises) of a certain frequency are created. If all these blocks are the same size, the sound of the same frequency is created, which increases the background, increasing the overall amplitude of sound waves. Therefore, manufacturers create tire structures in such a way that the tread blocks are different sizes, expanding the range of sound frequencies when touched rubber with an expensive and overall noise level becomes much smaller.
What rubber is softer and quieter
Undoubtedly, much quieter winter. This is due to tread height and composition feature (including), which is much softer due to the temperature mode of use. Show intermediate (medium) results.
Noise is determined in parallel with other characteristics of automotive tires on special tests. Measurements pass on Speed \u200b\u200b80 km / h. The sound level from the tire varies from 74 dB. up to 82 dB. Such a large interval is associated with the type of tires (winter or summer) and other indicators, whether it is a tread pattern, the type of rubber mixture, the area of \u200b\u200bcontact with the road web, the level of air pressure in the wheels. First of all, these tests pass on special stands, and then tires are experiencing in real road conditions.
In early 2014, at the Pirelli polygon in Italy, testers were tested by the main world manufacturers, according to which the winner was the winner for all indicators:
In terms of noise, these tires ranked second, dividing it with Pirelli P Zero., Barum Bravuris 3HM., Kumho Solus HS51. The third place went Dunlop Sport Maxx RT and Hankook Ventus S1 EVO 2.
The winner in terms of the noise was the wheels of the Finnish manufacturer Nokian, model:
Line XL (quieter and silent tires)
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In the general ranking, these tires occupied just a sixth position. Outsiders in terms of noise turned out to be Goodyear Eagle F1. and Bridgestone Potenza S001., while trying in the overall rating of the 4th and 5th place, respectively.
Thus, prizes in the nomination "Noise level" were distributed as follows:
- Pirelli, Barum, Kumho.
- Dunlop, Hankook.
The average price per set of tires among all sizes is:
- Nokian - 26000 rubles;
- Pirelli - 50,000 rubles;
- Barum - 20000 rubles;
- Kumho - 26,500 rubles;
- Dunlop - 28000 rubles;
- Hankook - 36,000 rubles.
It is worth noting that the noise level is far from the most important and essential parameter for which it is worth choosing tires for the car. The main still is other properties, such as braking, handling, aquaplaning, clutch. The noise of rubber is one of the latter, although important characteristics, and it is desirable that this indicator be optimal, maximum with "two waves", which is quite enough for comfortable movement.
The video shows new winter tires from Nokian with silent sidewall technology.
As one race car spoke: "The only car in the world who does not need additional noise isolation is Rolls-Royce. All the others need it." Therefore, no matter how you try to choose tires with a minimum level of noise, if the car is unsatisfactory, it will decide little.
