Testing of brake discs, brake drums, friction pads and brake shoes

Testing of braking systems and brake components

LBOSMAL Testing Laboratory provides compreherake shoe and brake lining testing, as well as complete brake system testing, including testing according to UN Regulation No. 90 (UN R90 / ECE R90).

Testing is performed using specialised laboratory facilities, including the full-scale LINK Model M3000 Brake Dynamometer, which enables functional, effectiveness, friction, wear, durability and NVH testing of disc and drum brakes.

We perform testing according to UN type-approval regulations, SAE, ISO and JASO standards, OEM specifications, as well as customer-specific test procedures and individually agreed test programmes.

BOSMAL has over 50 years of experience in brake system testing, combining laboratory and bench testing with testing performed on complete vehicles.

ASK ABOUT BRAKE SYSTEM TESTING

UN Regulation No. 90 covers, among others:

• replacement brake discs,
• replacement brake drums,
• replacement brake lining assemblies,
• replacement drum-brake linings.

BOSMAL performs testing in support of the type-approval process according to UN Regulation No. 90, using laboratory test equipment, brake dynamometer facilities and – where required by the applicable procedure – complete test vehicles.jne, dynamometr hamulcowy oraz – w zakresie wymaganym przez odpowiednią procedurę – pojazdy badawcze.

The detailed test programme depends on the type of component, its application, vehicle category and the applicable requirements of UN Regulation No. 90.

Depending on the specific case, the scope may include:

• inertia dynamometer testing among others: Thermal Fatigue, High load, Alternative performance,
• geometric and dimensional analysis,
• chemical composition and material,
• mechanical properties,
• vehicle testing.

The applicable scope and test methodology are determined individually according to the component and the required type-approval procedure.

ASK ABOUT UN REGULATION NO. 90 TESTING

BOSMAL performs testing according to SAE J2707 – Wear Test Procedure on Inertia Dynamometer for Brake Friction Materials.

The procedure defines inertia dynamometer testing used to characterise wear rates of automotive service brake friction materials, particularly:

• disc brake pads,
• brake shoes and linings.

Testing provides controlled and repeatable laboratory conditions for evaluating the behaviour of friction materials and analysing the influence of operating parameters on wear.

SAE J2707 testing can support:

• comparison of different friction materials,
• assessment of design variants,
• product benchmarking,
• friction material and component development,
• validation of new solutions,
• analysis of wear depending on operating conditions.

BOSMAL performs testing according to SAE J2522 – Inertia Dynamometer Disc and Drum Brake Effectiveness Test Procedure, commonly known in the industry as AK-Master.

The procedure is used to evaluate brake friction material effectiveness under defined braking conditions and to assess its behaviour as key operating parameters change.

The test programme considers the influence of parameters including:

• brake pressure,
• speed,
• temperature,
• braking sequences,
• heating and cooling conditions.

SAE J2522 provides repeatable conditions for comparing friction materials and can support:

• new product development,
• friction material selection,
• comparison of alternative designs,
• design validation,
• quality evaluation,
• component benchmarking.

LINK Model M3000 Brake Dynamometer

The LINK Model M3000 enables full-scale testing of disc and drum friction brakes within a wide range of functional, performance and durability test programmes.

Components and systems tested can include:

• brake pads,
• brake shoes and linings,
• brake drums,
• solid brake discs,
• ventilated brake discs,
• brake discs of different designs and materials,
• brake calipers,
• complete brake assemblies,
• conventional hydraulic brake systems.

The facility enables operating conditions to be reproduced for a wide range of vehicle applications – from passenger cars and SUVs to light commercial vehicles.

Inertia and Driving Condition Simulation

The LINK M3000 enables dynamic inertia simulation over a broad range, allowing test conditions to be matched to different vehicle types and brake system configurations.

Precise control of rotational speed, brake pressure, temperature and cooling conditions enables both standardised test procedures and customer-specific development programmes to be performed.

Data Acquisition

During testing, the system can record and analyse in real time parameters including:

• braking torque,
• rotational speed,
• linear speed,
• deceleration,
• brake pad or shoe temperature,
• brake disc or drum temperature,
• brake pressure,
• acceleration,
• fluid displacement,
• actual inertia,
• cooling air temperature,
• cooling air humidity,
• cooling air velocity,
• DTV – Disc Thickness Variation,
• sound pressure level,
• noise peak frequency,
• noise peak duration.

Signals can be recorded at sampling rates of up to 1000 Hz.

BOSMAL can also support the analysis and interpretation of test results and the comparison of different friction materials, component designs and brake configurations.

Video Acquisition and NVH Testing

The test chamber is equipped with a video acquisition system enabling the tested brake assembly to be recorded during the test.

Testing can also include simultaneous acquisition and analysis of:

• brake noise,
• vibration,
• acoustic event frequency,
• acoustic event duration.

Parametry stanowiska LINK Model M3000

The LINK M3000 is equipped with a Static Torque System, a low-speed, high-torque drive system designed for testing brake behaviour at very low rotational speeds.

The system can be used for:

• static brake breakaway testing,
• static torque testing,
• creep behaviour evaluation,
• creep/groan and related low-speed brake phenomena.

System capability:

• braking torque up to 5650 Nm,
• rotational speed up to 18 rpm.

The LINK M3000 enables brake tests to be performed under humid and wet operating conditions, including direct water application to the tested brake assembly.

The Water Spray System can be used to evaluate brake behaviour under conditions representative of exposure to water or wet-road operation.

Maximum water flow:

up to 7 l/min.

BOSMAL Testing Laboratory performs a broad range of tests on brake friction components and their mating parts.

Brake Discs

We test, among others:

• solid brake discs,
• ventilated brake discs,
• brake discs of different designs,
• brake discs manufactured from different materials,
• brake discs intended for different vehicle categories.

The scope can include assessment of:

• brake effectiveness,
• interaction with the friction material,
• thermal behaviour,
• resistance to high loads,
• thermal fatigue and cracking,
• wear,
• durability,
• DTV – Disc Thickness Variation,
• NVH – Noise, Vibration and Harshness.

Brake Drums

Brake drums and their associated friction components can be tested under controlled laboratory conditions reproducing representative operating loads.

Testing can include evaluation of:

• effectiveness,
• friction characteristics,
• wear,
• thermal loading,
• durability.

Brake Pads

Brake pad testing can include:

• friction characteristics,
• coefficient of friction,
• brake effectiveness,
• wear,
• behaviour at different temperatures,
• influence of pressure and speed,
• resistance to mechanical and thermal loading,
• NVH testing,
• shear testing,
• compressibility testing,
• hardness testing,
• dimensional inspection.

Brake Shoes and Linings

Testing of brake shoes and drum-brake linings can include assessment of:

• friction characteristics,
• effectiveness,
• wear,
• durability,
• mechanical properties,
• dimensional conformity.

BOSMAL performs bench pressure testing of brake system components to assess leak-tightness, durability and resistance to pressure loads.

The scope includes, among others:

Pressure Pulsation Testing

Brake system components can be subjected to repeated pressure changes according to a defined load profile or customer-specific procedure.

Pressure pulsation testing enables assessment of component behaviour under long-term cyclic loading representative of service conditions.

Burst Pressure Testing – Burst Test

Hydraulic destructive testing used to determine a component’s resistance to increasing pressure up to:

• failure,
• permanent deformation,
• loss of leak-tightness,
• rupture.

Leak-Tightness Testing

Leak-tightness testing of components and connections used in braking systems can be performed according to project requirements, applicable procedures or customer specifications.dnie z wymaganiami określonego projektu lub procedury.

BOSMAL performs brake system testing on complete vehicles, enabling braking performance to be assessed under actual vehicle operating conditions.

The scope includes:

• vehicle braking performance testing,
• component mountability and fitment testing,
• development testing,
• testing in support of vehicle type approval.

Vehicle Braking Performance Testing

Testing can include:

• braking distance measurement,
• deceleration measurement,
• brake system response time measurement,
• force measurement and other braking process parameters,
• service braking system testing,
• secondary braking system testing,
• parking braking system testing,
• assessment of the ability to hold a vehicle stationary on a gradient.

Vehicles tested can include:

• passenger cars,
• commercial vehicles and trucks,
• trailers,
• semi-trailers,
• vehicles equipped with hydraulic braking systems,
• vehicles equipped with pneumatic braking systems.

Testing can be performed according to applicable requirements including:

• UN Regulation No. 13,
• UN Regulation No. 13-H,
• UN Regulation No. 90.

Contactless methods can also be used to measure vehicle speed and distance.

BOSMAL performs mechanical testing of brake system components to evaluate their material, structural and functional properties.

Parking Brake Functionality and Durability Testing

Testing involves cyclic operation of a mechanical parking brake under defined loading conditions.

The test can be used to evaluate:

• correct system operation,
• mechanism durability,
• changes in parameters over the service-life cycle,
• resistance to repeated operation.

Shear Testing

Measurement of the force required to separate the friction material from its backing plate or supporting component.

The test provides information on the strength and quality of the bond between the friction material and its structural support.

Compressibility Testing

Assessment of the deformation of friction material under a defined compressive load representative of brake caliper actuation.

Hardness Testing

Hardness measurements of brake system components can be performed using:

• Vickers,
• Brinell,
• Rockwell methods.

Dimensional and Geometric Measurements

Dimensional and geometric inspection of braking system components and verification of conformity with:

• technical drawings,
• design requirements,
• customer specifications.

BOSMAL operates a system designed to perform controlled testing of mechanical parking brakes by applying a defined force to the brake cable.

The system enables:

• functional parking brake testing,
• cyclic testing,
• durability testing,
• controlled reproduction of parking brake actuation.

System parameters:

• maximum force: 3.3 kN,
• force application rate: up to 2600 N/s.