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The present investigation deals with the design and shape optimization of the steel insert used in the hand brake valve to withstand the impact load during brake off condition. This hand brake valve is used in the vehicles for parking brake application. It consists of a steel insert with a helical coil spring for locking and unlocking of a lever during brake on and off condition. Also a torsion spring with a cam mechanism is used for opening and closing of a hand brake valve. When the lever is locked the flexible elastic object (torsion spring) stores the mechanical energy when it is twisted. When it is unlocked (braking off) it exerts a force (actually torque) in the opposite direction, proportional to the angle it is twisted. During the braking off condition the steel insert gains the angular velocity from the stored mechanical energy of the torsion spring.

The present investigation deals with the failure load prediction during the wrong procedure of unlocking the hand brake valve. The design of the hand brake valve top cover should have adequate strength such that the driver cannot move the lever without lifting the sleeve during brake off condition. The objective of this work is to design the top cover with higher strength such that it requires more load during wrong procedure of unlocking the valve. In this study, the nonlinear analysis is conducted (which includes three types of nonlinearities namely material, geometry and contact) in order to study the strength of the top cover during abuse condition. The design adequacy of the top cover is estimated by elasto plastic analysis. The maximum load carrying capacity of the top cover is determined from Force Vs Deformation plot which is good in agreement with the experimental results. Various design iterations are carried out to propose the appropriate design.

Leveling valves are typical pneumatic flow control valves which are fitted in the vehicle chassis to supply or deplete air pressure in the bellows so as to maintain the chassis always in a horizontal position, under the loaded or unloaded condition of vehicle or trailer. Therefore it is necessary to study the flow rate of air for different operating angles of leveling valve corresponding to the vehicle load. Filters are provided, one at the upstream and two at the downstream in order to prevent dust from entering into the valve and bellows. All flow control valves have an inherent flow characteristic that defines the relationship between ‘valve opening’ and flow rate under constant pressure conditions. Hence Computational Fluid Dynamics (CFD) can be utilized as a useful design tool to optimize the flow area of leveling valve and also to study the difference in pressure between upstream and downstream of a filter in order to push the fluid through the filters.