Thermal analysis of the brake frictional lining pad

The problem and the task formulation

When the client wanted to develop the braking system, he needed our services to clarify whether the heat flow in the friction lining material exceeded the allowed limit and to determine the temperature to which the braking pad material was heated during braking.

To make heat calculations, we were given the drawings for the drum brake of the rear wheel of the 5-t weight forestry machine. The dimensions of the braking pads were determined on the basis of assemblage of the unit and the allowed pressure in the friction couple.

Problem-solving technique

Our client did not have to provide to us a detailed description of the vehicle, because we determined all initial data with the minimum information available.

First, we calculated the required dynamic scenarios and simulated behavior of the loaded machine during braking from the nominal transport velocity to the full stop, and then we created a 3D model of the entire unit. All procedures were performed under CAD/CAE/PDM. 3D modeling and FEA analysis was carried out using I-DEAS Software by EDS Company.

After that we created scenarios that simulated behavior of the rated model when heated and analyzed distribution of heat during machine stoppage. These scenarios were calculated using FEA analysis. Input heat load was varying in time depending on the braking dynamics.

After calculations, the heat load scenarios together with our recommendations were submitted to the client to take the final decision about fitness of the design.

Results

Our calculations allowed the client to make sure that the braking system secured safe braking of the forestry machine, that heat flown in the lining material did not exceed the allowed limit and that in the worst case of braking there was no overheating of the braking lining material

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Heat analysis showed that when this system is used on high-weight machines, it should be developed further and heat sink should be improved. Without our cooperation the client would have had to start production of pilot samples, make expensive stand and full-scale testing to obtain the required data and only after that he could make modifications in the design. With our help he performed the entire work within three weeks.