Refine Your Search

Topic

Search Results

Standard

Brake Insulator Damping Measurement Procedure

2024-08-12
CURRENT
J3001_202408
This procedure is applicable to modes from 500 Hz and 13000 Hz. The parameters measured with this procedure are defined as the damping factor, ξ, for the first nine vibration modes of the beam. The measurement will be done in free-free conditions and with temperature.
Standard

Brake Insulator Design Guidelines

2024-02-26
WIP
J3317
This document applies to shims only and will outline insulator design guidelines for improved manufacturability, cost and optimized product performance (Durability, bondability…)
Standard

Brake Insulator Damping Measurement Procedure

2023-06-19
HISTORICAL
J3001_202306
This procedure is applicable to modes from 500 and 13,000 Hz. The parameters measured with this procedure are defined as the damping factor, ξ for first nine vibration modes of the beam. The measurement will be done in free-free conditions and with temperature.
Standard

Inertia Dynamometer Brake Squeal Noise Test Procedure for Vehicles without Regenerative Systems

2022-10-07
CURRENT
J2521_202210
The SAE J2521 procedure applies to high-frequency squeal noise occurrences for on-road passenger cars and light trucks below 4540 kg of GVWR. The procedure incorporates high-temperature and low-temperature test matrixes but does not fully account for the effects of the environment on brake squeal. For this test procedure, squeal occurs when the peak noise level is at least 70 dB(A) between 1.25 kHz and 16 kHz for tests using full suspension corners or full axle assemblies or between 2 kHz and 16 kHz for brakes not using a full suspension corner. Before using this recommended practice for chassis dynamometer testing, review in detail the specifics related to at least (a) instrumentation, including in-cabin microphones, (b) threshold levels for noise detection, (c) temperature control priority between the front and rear axles, (d) vehicle loading and load distribution, (e) cooling air and environmental conditioning, and (f) detailed nomenclature and labeling of channels and sensors.
Standard

Verification of Brake Rotor and Drum Modal Frequencies

2022-09-08
CURRENT
J2933_202209
This document describes standard test methods, analysis methods, and reporting methods for measuring the resonant modes of automotive disc brake rotors and drums for design/development and production verification of these components.
Standard

Disc and Drum Brake Dynamometer Low-Frequency Noise Test Procedure

2021-01-27
CURRENT
J3002_202101
This test procedure outlines the necessary test equipment (test fixture, dynamometer, data acquisition system, etc.) and test sequence required to test for low-frequency brake noise (200 Hz to 1.25 kHz) on a brake noise dynamometer. It is intended to complement SAE J2521, which focuses on high-frequency brake squeal. This RP applies to passenger cars and light trucks with a gross vehicle weight rating below 4536 kg. Before using this RP for heavier vehicles, consult and agree with the test requestor and the testing facility.
Standard

Automotive Disc Brake Pad Natural Frequency and Damping Test

2020-12-18
CURRENT
J2598_202012
This procedure is applicable to brake pad modes between 500 Hz and 16 kHz. The parameters measured with this procedure are defined as the first three natural frequencies, fn (n = 1, 2, 3), and the corresponding loss factors, η.
Standard

Taxonomy and Guidelines for Design, Fabrication, and Installation of Brake NVH Fixtures for Inertia Dynamometer Testing

2020-05-22
CURRENT
J3152_202005
This IR defines a general taxonomy (classification) of the most common fixture designs. This IR provides guidelines for design, fabrication, and installation to improve the way tests repeat, reproduce, and correlate to vehicle conditions. The different types of fixtures in this IR (including their preloading) apply to single-ended brake inertia dynamometer NVH testing, with a frequency range between 1.25 kHz and 16 kHz (per SAE J2521). This IR applies to passenger car and light trucks with a gross vehicle weight rating of 4536 kg or below. This IR does not address other sources of variability such as (a) test procedure itself, (b) environmental conditions, (c) dynamometer design, including its NVH test chamber, (d) data collection and data analysis methods, and (e) part-to-part, batch-to-batch, and design-level variation for brake and suspension hardware.
Standard

Friction Material Elastic Constants Determination through FRF Measurements and Optimization

2019-11-20
CURRENT
J3013_201911
This SAE Standard specifies necessary procedures and control parameters in estimating anisotropic elastic constants of friction material based on pad assembly FRF measurements and optimization. It is intended to provide a set of elastic constants as inputs to brake NVH simulation, with the objective of ensuring pad assembly vibration correlation between simulation and measurements.
Standard

Brake Dynamometer Squeal Noise Test Procedure for Regenerative Systems

2019-09-19
WIP
J3211
The SAE J3211 procedure applies to brake squeal evaluation using single-ended inertia dynamometers for friction couples used on vehicles with regenerative braking systems. This RP applies to squeal noise occurrences for on-road passenger cars and light trucks with a gross vehicle weight rating of 4536 kg or below. The procedure incorporates aspects related to (a) minimum inertia dynamometer capabilties, (b) fixture requirements and setup, and (c) test sequences with emphasis on brake temperatures, brake pressure profiles, and strategies to represent brake blending.
Standard

Automotive Brake Noise and Vibration Standard Nomenclature

2017-12-20
CURRENT
J2786_201712
This document defines various vehicular noises and vibrations that are attributed to being created by the foundation brake components of the vehicle, particularly on passenger cars and light trucks. These definitions cover both disc and drum brakes. The frequency ranges from near zero Hz (tactile sensations) all the way up to 17 kHz, or the upper limit of normal hearing. These noises and vibrations may either directly radiate off the brake system or provide the excitation energy that causes other vehicle components to react.
Standard

Automotive Vehicle Brake Squeal Test Recommend Practice

2017-07-24
CURRENT
J2625_201707
This procedure is applicable to squeal type noise occurrences for passenger car and light truck type vehicles that are used under conventional operating conditions. For the purposes of this test procedure, squeal is defined as occurring between 900 and 18 000 Hz.
Standard

Brake Insulator Damping Measurement Procedure

2016-04-20
HISTORICAL
J3001_201604
This procedure is applicable to modes from 500 and 13,000 Hz. The parameters measured with this procedure are defined as the damping factor, ξ for first nine vibration modes of the beam. The measurement will be done in free-free conditions and with temperature.
Standard

Brake Rotor Thickness Variation and Lateral Run-Out Measurements

2015-10-02
WIP
J3111
The scope of this recommended practice is to establish definitions and recommended methods for the measurement of lateral run-out and disc thickness variation in the laboratory and vehicle for passenger cars and light duty trucks up to 4546 kg gross vehicle weight. This recommended practice will breakdown the instrumentation (sensors and sizes), test setup, and data processing.
Standard

Disc and Drum Brake Dynamometer Squeal Noise Test Procedure

2013-04-11
HISTORICAL
J2521_201304
The SAE J2521 procedure is applicable to high frequency squeal noise occurrences for on-road passenger car and light trucks below 4,540 kg of GVWR. The procedure incorporates high temperature and low temperature test matrixes, but does not fully account for the effects of the environment on brake squeal. Much research is currently underway in this area and can potentially be incorporated in future revisions. For the purposes of this test procedure, squeal is defined as peak noise levels equal to or above 70 dB(A) between 1.25 kHz and 16 kHz for tests using a full suspension corners or full axle assemblies, or between 2 kHz and 16 kHz for brakes not using a full suspension corner.
Standard

Friction Material Elastic Constants Determination through FRF Measurements and Optimization

2012-10-09
HISTORICAL
J3013_201210
This SAE Standard specifies necessary procedures and control parameters in estimating anisotropic elastic constants of friction material based on pad assembly FRF measurements and optimization. It is intended to provide a set of elastic constants as inputs to brake NVH simulation, with the objective of ensuring pad assembly vibration correlation between simulation and measurements.
Standard

Automotive Disc Brake Pad Natural Frequency and Damping Test

2012-07-16
HISTORICAL
J2598_201207
This procedure is applicable to brake pad modes between 500 Hz. and 16 kHz. The parameters measured with this procedure are defined as the first three natural frequencies, fn (n=1, 2, 3), and the corresponding loss factors, η.
Standard

Verification of Brake Rotor Modal Frequencies

2011-03-01
HISTORICAL
J2933_201103
Provide description of standard test methods, analysis methods, and reporting methods for measuring the resonant modes of automotive disc brake rotors and drums for purpose of design and production verification of these components.
Standard

Brake Insulator Damping Measurement Procedure

2011-02-04
HISTORICAL
J3001_201102
This procedure is applicable to modes between 1500 and 15 000 Hz. The parameters measured with this procedure are defined as the damping factor, ξ for first three bending modes of the beam. The procedure will focus on bending modes only.
X