Portfolio Project

• Design of Railway Axle

• Apr 2019 - Jul 2019

The objective of this project is to make an assessment of a Railway axle subjected to loads. Initially, studied the effect of the loads acting on the system due to the masses in motion, then, the ones of the loads due to the braking system. By applying the superposition principle to the two cases, identified the most stressed section in the axle and ensured that the railway axle is not going to plasticize by verifying that the evaluated equivalent stress in the critical section is lower than the yield strength of the Axle material. Secondly, assessment is focused on the assembly of Wheel and Axle, the corresponding objective is carried out by employing the shrink-fit method, in which the wheel is pre-heated to 30-40% of the melting temperature of the material [Due to this process, in atomic-level covalent bonds become weaker in Fe-atom, as a result slipping between two atomic-planes occurs] thermal-expansion phenomenon incurs. Then, the Axle which is at atmospheric temperature is manoeuvred carefully into a Wheel specified location and allowed to cool down to room temperature. As a result, a strong bond between the Axle and Wheel is formed, the corresponding phenomenon is referred to as “Shrink-fit”. The corresponding assessment is conducted in three ways, i.e initially by considering the “Airy’s Formulation”, “Grammel’s Method” & finally by utilising a commercial FEM tool (Abaqus software). Finally, the Fatigue assessment is carried out in two approaches, i.e. Local & Global approaches. Both approaches are carried out by considering all internal force fields acting on the Shaft, critical section is identified by considering where maximum force fields are occurring which is at the left-wheel position. In conclusion, the corresponding stress fields are determined, from this evaluation, made conclusions by considering the stresses induced in the axle due to Bending-moment and Torsional-moment. Appropriate, influential factors are employed by considering, Fatigue-concentration-factor concerning the Notch-geometry next to the left wheel position, along with Dimensional-effect, Surface-factor.

• Design of Hydraulic Cylinder

• Apr 2019 - Jul 2019

Aim of this investigation is the evaluation of stress and strain fields in an internally pressurized hydraulic cylinder. Experimental measurements, analytical approach and numerical models built in Abaqus software (Two types of approximations were considered during the assessment) are adopted and their results are then compared. Stress concentration factor is also predicted via numerical models and the gap with the theoretical, expected values were detailed.

• Design of Pressure Vessel

• Apr 2019 - Jul 2019

Pressure-vessel is a container designed to hold gases or liquids which are substantially at higher Pressure & temperature. Without appropriate design considerations, fully-desired-functioning of the vessel can be attained by considering the safety and limitations of the vessel component. Design parameters that play a substantial role in the reliability and durability of the vessel component are “Maximum-safety-operating-pressure”, “Maximum-safety-operating-temperature”, “Safety-factor”, “Corrosion-resistance to the working environment”. With an appropriate selection of the “Non-Destructive-Testing” (NDT) tool, RELIABILITY of the entire system can be conducted such as Ultrasonic-testing, Radiography. Moreover, NDT is the final phase of the design process, before this, by employing “Finite element-method” comprehensive-design analysis of the system is carried out by considering the above-mentioned design parameters. Application of pressure-vessel is extensive, such as; Transport and storage of fluids for industrial and medical applications; Fire-extinguisher; Methane-gas-storage. By considering these aspects into account, Design assessment for a pressure vessel used for storing a pressurized gas in a cylindrical-shell with hemispherical-ends is comprehensively carried out. Comprehensive assessment is divided into three-stages, i.e. “Static assessment of the structure”, “Fatigue-assessment of the structure”, “Assessment and validation of analytical - solution with FEA solution” & Finally, assessment of Crack propagation is conducted.