Burst Pressure Study in Damaged Hydraulic Rigid Brake Pipes on Passenger Cars 2019-36-0001
Hydraulic brake pipes are responsible for fluid flows and as consequence the proper functionality of the most important safety system in passenger vehicles. Even so, this component has no much development since it was applied in the 1930s. In fact, the brake pipes can be particularly vulnerable components, being mainly in an exposed condition under the vehicle and near of components with relative movement. Externally it needs to survive a wide range of environmental conditions whereas internally it must withstand pressurized brake fluid. Brake pipes failures is an obvious safety hazard. Using simulations with car body, burst and corrosion bench test and multiple linear regression, this paper attempts to present, basing the pipes lifetime in the burst bench test, how the pipes are really vulnerable or not to damages caused by interference with other components, corrosion or even in frequent abrasion. As well as pipes behavior during interference, how such as corrosion in spot exposed regions degrades the pipes, how such as quantity, type and bending location influence the lifetime, which are the most relevant damage factors, how the damage usually occurs on vehicles, and specify an equation capable of projecting burst pressure considering the damage dimensions as variables. This paper shows the most vulnerable regions and pipes diameter most affected, clarify how the bends impact on the pipes lifetime and defines a equation able to correlate a pipe lifetime prediction based on the damage dimensions.