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Braking system components generally are safety critical products. Commercial vehicles braking systems are of highly safety critical as they pose a serious threat to life and property. Therefore, a system must be designed and validated to minimize the effects of component failure of these portfolios of products. In order to avoid accidents due to brake failures, this paper mainly focuses on analysis of loss of pneumatic fluid pressure in the components of the braking systems. Leakage of pneumatic fluid pressure through the sealing in braking system is one of the major reasons for the failure of the brakes in the vehicles. The aim of the present study is to simulate the lab failure and improve the design using finite element analysis. Also, the optimized design is validated by experimentally. A finite element model is developed in Ansys Workbench to study the behavior of the sealing ring under assembly conditions.

In recent days, the usage of disc brake is increased acutely in commercial vehicle applications apart from the passenger vehicles. The main advantage of using disc brake is reducing the stopping distance, temperature and wear between the disc and pad. During the braking, kinetic energy of the vehicle is converted into thermal energy due to the friction between disc and pad. To maintain the temperature between the disc and pad is critical for the overall performance of the disc brake and safety of the vehicle. The process of vehicle braking is a dynamically thermal structure coupling problem which is complex in nature. In this study, temperature between the disc and pad is determined using Finite Element Analysis for two different pad configurations. As per recent vehicle norms by the government the axle load is increased by 20 % which requires increased braking force and will leads to high temperature in the disc pad interface.

Lift axle is essentially provided in commercial vehicles to increase the vehicle’s load-carrying capacity. The axle is lowered in the case of a high payload and the load is evenly distributed among the wheels both on fixed axles and the lift axle. This ability to lift the axle implies better maneuverability in turns, better fuel consumption, and less wear and tear on the tires and brake shoes. Also, it will reduce the damage to the road surfaces. This lowering and lifting of the lift axle are controlled by a series of valves together called the Lift Axle Control System (LACS). This LACS must consider the vehicle load condition, the ignition state, and gear state to decide if the axle must be lifted or lowered. This paper deals with the modeling and simulation of the LACS system at the vehicle level and optimize the design for the respective desired design solution.

Generally the brake system products are mounted on chassis with brackets which are subjected to dynamic loads due to road undulations. Exhaust brake is used to restrict the engine exhaust flow passage and thereby creates a back pressure in the engine for reducing the engine speed. This in turn reduces the vehicle speed. This is widely used in the vehicles operating in the hilly areas. This product is mounted on the exhaust passage and the air cylinder sub-assembly which actuates the exhaust brake is mounted on a bracket. Automotive industries perform durability tests on vehicles to reduce the failure on end-user environment. An assembly which has cleared the durability test got failed on addition of a spring into the assembly. The inclusion of spring is for enhancing the performance of the overall assembly.

Reliable sealing solutions are extremely important in commercial vehicle industry because sealing failures can cause vehicle breakdown, damage of equipment or even accident, incurring expenses that are substantially higher than the costs of just replacing the damaged seals. Consequently, new seal designs must be experimentally verified and validated before they can be implemented. In this study, Mooney - Rivlin hyper elastic material model is used to simulate the sealing behavior during dynamic conditions. The seal under study is a large diameter lip seal made of Neoprene® rubber (NBR) A finite element model to study the response of the seal under dynamic conditions was developed. The analysis took into account the mating parts dimensions and the lip seal parameters. Three designs were proposed and verified. The seal design is optimized using non-linear FEA and validated. Results include contact pressure, deflection and strain experienced by the seal during actuation.

Pneumatic valves are widely used in heavy commercial vehicles’ air braking systems. These valves are mainly used in the braking system layout to maintain the vehicle stability during dynamic conditions. Rubber components are inevitable in valves as a sealing element, and it is very difficult to predict the behavior due to its nonlinear nature. Basically, this valve efficiency is defined in terms of performance and response characteristics. These characteristics are determined in the concept stage itself using 1D simulation software. AMESim software has a variety of elements to use in a unique way for performance and response behavior prediction. For pneumatic valves, 1D analysis is an effective method and it gives good correlation with actual test results. During the modelling of pneumatic valves, some of the contacts between rubber and metals are controlled by various parameters such as damping, contact stiffness and desired phase angle.