Iombriller, S., Eiras, D., and Souza, M., "Methodology for Developing and Validating Air Brake Tubes for Commercial Vehicles," SAE Technical Paper 2012-36-0272, 2012, doi:10.4271/2012-36-0272.
The pneumatic air brake system for heavy commercial trucks is composed by a large number of components, aiming its proper work and compliance with rigorous criteria of vehicular safety. One of those components, present along the whole vehicle, is the air brake tube, ducts which feed valves and reservoirs with compressed air, carrying signals for acting or releasing the brake system.In 2011, due to a lack of butadiene in a global scale, the manufacturing of these tubes was compromised; as this is an important raw material present on the polymer used so far, PA12.This article introduces the methodology of selecting, developing and validating in vehicle an alternative polymer for this application. For this purpose, acceptance criteria have been established through global material specifications, as well as bench tests and vehicular validation requirements.The possible alternative materials have been tested under different chemical, mechanical and thermal conditions, also respecting specific characteristics on heavy commercial vehicles application. In addition, static, dynamic and cyclic aging tests were performed in order to simulate its performance through the entire life of the vehicle. The analysis of parameters such as cost, assembly impact, handling and storing in assembly line and serviceability were also evaluated along the study.A PA6.10 material was validated considering performance material standards, assembly line conditions and Brazilian commercial trucks application.