South and Southeast Asia Brake Conference and Exhibition 2020

Fundamentals of Brake design

Prof. Dr. John David Fieldhouse - Advisor to Industry

Software development has progressed to a state where the engineer needs to input only base information and the result is provided by an appropriate program. This is excellent for time savings within the industry but a complaint by many senior engineers is that new recruits can readily operate the programs but rarely understand the fundamentals driving that program. As such they are not able to modify, develop or “tune” it to suit the differing needs of a company and indeed “add to” or move towards optimizing a brake design. More important is that there is a blind faith in the answer with little recognition of potential issues – NVH being at the forefront of many braking problems.

This presentation will consider the important aspects of brake design – brake sizing, load transfer & brake balance, electronic braking distribution (EBD), ABS, thermal aspects& NVH. There will be consideration given towards electric braking including energy recovery systems. It is expected that a case study of a tractor/semi-trailer will serve to demonstrate the difficulties of brake design when the load magnitude and position is generally unknown. Such situations demand a common approach (a standard) but this tends to existing problems not being addressed – trailer slew, jackknifing and rollover.

On emissions of brakes

George Ostermeyer - Professor Institute of Dynamics and Vibrations

The process of vehicle emission reduction had a long time only the engine in focus. With the new emissions standards, the engine emissions are lower than the emissions generated by abrasion of tires and brakes. Consequently, R & D now turn to the brake missions. In many places now objectified measurement standards for brake particle emissions will be developed.

An analytical approach evolves from the boundary layer dynamics of brake pads, which reveals more and more the central role of wear for the emergence of friction and emission dynamics.

The talk will concentrate on European activities in measurement and show some new research activities in emission generation by friction in brakes.

Ingredient Variability and Its Effect on Friction Materials Performance

Eros Sales - Global Friction Application director, ITT Motion Technologies

Friction materials generally may contain up to 20 different ingredients. Considering that each raw material has its intrinsic variability, the effects that the variability can generate on the final product are evident if there are no well defined strict tolerances on the characteristics under control.

The ingredients used for the preparation of friction material (NAO or Low Met or Semi Met) can be divided in few categories: binders, metals, fibers, fillers, abrasives and lubricants. Tolerances are defined based on laboratory analysis and technical papers of the suppliers. Each ingredient has a specific role and can modify the characteristics of the final product. Density, porosity and compressibility can be influenced by phenolic resin variability, while friction level can be modified by different lubricant / abrasives ratio.

Mechanical strength depends on fiber type and content (metallic, inorganic and organic). The control of the incoming batch of raw materials is mandatory to maintain under control all the characteristics of the friction material and prevent issues in the market.