For the train axle, you are to design the shaft, select suitable bearings and determine appropriate dimensions for disk brakes mounted onto the shaft. For this, you must calculate and/or determine the...

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For the train axle, you are to design the shaft, select suitable bearings and determine appropriate dimensions for disk brakes mounted onto the shaft. For this, you must calculate and/or determine the following: · The loads and stresses in the axle to determine the minimal required diameter in the critically loaded section(s) of the shaft – draw a Free-Body Diagram (FBD) for all shear forces, bending moments and torsion occurring; the FBD must be part of your submission. · The selection of suitable ball or roller bearings that is able to run for 5,000 hours under the occurring loading conditions (assuming an average speed of travel of 60km/h travel of the train). · You do not need to design the brake rotor in all detail, but you are to determine a suitable major diameter and contact diameter (average) for the pads. · Beyond this, you must ensure deflections in the shaft at the critical diameter(s) not to become too great. Also show that the shaft will not fatigue under the given conditions with appropriate reliability. You may make reasonable simplifications (FS and brake force for instance may be neglected for fatigue life). · The technical drawing of the shaft should visualize separate shoulders for each set of machine elements mounted onto it and must follow AS1100. · Explain all choices for diameters, sizes, etc. and your overall approach briefly as outlines above. Use the following parameters: Globally, the standard track gauge is 1435mm (that is the distance between the tracks; The profile width of the track for a wheel to run on is just under 70mm – the width of the part of the wheel running on the track should be larger (within reason) than this. The diameter of the wheel, at the running surface is 750mm, the total width of the wheel should not exceed 100mm – use the figure below as reference. · The shaft is made from ’normalized’ steel AISI 1095. · Assume a mass of the train acting on this axle of 5000 Kg. You should expect an occasional, additional shock loading due to bumps of 20% (assume this to be ‘moderate’ shock in your calculations). · The normal force FN that acts on the brake rotor through the brake pads cannot exceed 15kN. Assume the train to be in motion when the maximum brake force is applied. Yet, you are to ensure that under the maximum brake force, the wheels of the train will just not fully block. · You may choose the position of bearings and disk rotors on the shaft yourself, but the bearings should be placed closer to the wheels than the brake rotors. The shaft is to be symmetrical. · All other relevant design parameters have to be decided by yourself using the information provided in the unit’s textbook and lecture material. Be sure to mention sources for values, dimensions, etc. for calculations whenever applicable. You may neglect: · The vibration and critical speed of the shaft system. · Notches, fillets, etc. for axial securing and mounting of the wheels, bearings and brake rotors. · The designing of the brake rotor – determining the average radius where the brake pads act on the rotor will suffice. · The specific definition of the surface qualities (e.g. roughness) or fits in different sections of the shaft. Bonus points: · Calculate the amount and rate of emerging heat in the brake system that has to be dissipated for your specific set up of the brake system. · if you can make reasonable and well-argued suggestions for the surface qualities required (give values for averaged surface roughness and fits) for relevant sections of the shaft. · · FBS is the resulting brake force from FN – select suitable materials for brake pad and brake rotor and coefficient of friction resulting from this pairing. · FS is the force acting on the wheel in motion that acts against the resulting brake. · FL refers to the radial bearing reaction forces; assume an additional axial force component of 20% of the radial forces (which occurs when cornering, for instance).