Q3A A shaft is used to transfer power from a gear transmission to propel an air-propeller....

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Q3A A shaft is used to transfer power from a gear transmission to propel an air-propeller. The steady state torque is 159.15 Nm at a nominal operating speed of 6000 rpm. In a preliminary design, the shaft material is chosen to be AISI 4130 steel (annealed heat treatment, ground surface finish, Sut = 560 MPa, Sy = 361 MPa). The lateral load is estimated to be 1200 N. The axial load effect is small can be ignored. The mean torque can be calculated using the power and the rotational speed. For simplicity, the shaft axial dimensions are chosen. Only the shaft diameters remain to be the design parameters everywhere. For practical considerations, the required shoulder sizes, where applicable, are also given. Considering the possibility of moderate shock and moderate overload, a safety factor of 2.5 is recommended for the shaft against yield and fatigue failures. The gear is to be mounted to the shaft through standard key and keyway. Design diameters d, d, r and D in accordance with the DE-Langer-Gerber failure criteria for yield and fatigue based on the identified critical location. For your consideration, the fillet radius is taken to be about 1/4 of the step size. Comment on the criticality of the gear side of the shoulder. You must take at least one complete iteration to meet the requirements for strengths and geometric constrains at the shoulders. If a satisfactory design cannot be achieved in one iteration, point out clearly what to do next to meet all requirements, but do not carry out any further iterations due to time constraints. Use the attached charts for the stress concentration of shaft at the key location with key in place, the stress concentration in connection with bending of filleted round shaft, the stress concentration in connection with torsion of filleted round shaft. For simplicity, use the fatigue notch sensitivity of 1 for both normal and shear stresses. Use the attached table a reference for keyway sizing and choice of a fillet radius. The keyway depth is half of the key height. Sketch of the propeller shaft A min shoulder of 10 mm for helical gear mounting A min shoulder of 5 mm for bearing mounting di Prop load torque 15 L 225 D Fillet radius r A min shoulder of 5 mm for bearing mounting R 30 Critical location keyway .15 200 All linear dimensions are in mm. Detailed view of the shaft Q3A A shaft is used to transfer power from a gear transmission to propel an air-propeller. The steady state torque is 159.15 Nm at a nominal operating speed of 6000 rpm. In a preliminary design, the shaft material is chosen to be AISI 4130 steel (annealed heat treatment, ground surface finish, Sut = 560 MPa, Sy = 361 MPa). The lateral load is estimated to be 1200 N. The axial load effect is small can be ignored. The mean torque can be calculated using the power and the rotational speed. For simplicity, the shaft axial dimensions are chosen. Only the shaft diameters remain to be the design parameters everywhere. For practical considerations, the required shoulder sizes, where applicable, are also given. Considering the possibility of moderate shock and moderate overload, a safety factor of 2.5 is recommended for the shaft against yield and fatigue failures. The gear is to be mounted to the shaft through standard key and keyway. Design diameters d, d, r and D in accordance with the DE-Langer-Gerber failure criteria for yield and fatigue based on the identified critical location. For your consideration, the fillet radius is taken to be about 1/4 of the step size. Comment on the criticality of the gear side of the shoulder. You must take at least one complete iteration to meet the requirements for strengths and geometric constrains at the shoulders. If a satisfactory design cannot be achieved in one iteration, point out clearly what to do next to meet all requirements, but do not carry out any further iterations due to time constraints. Use the attached charts for the stress concentration of shaft at the key location with key in place, the stress concentration in connection with bending of filleted round shaft, the stress concentration in connection with torsion of filleted round shaft. For simplicity, use the fatigue notch sensitivity of 1 for both normal and shear stresses. Use the attached table a reference for keyway sizing and choice of a fillet radius. The keyway depth is half of the key height. Sketch of the propeller shaft A min shoulder of 10 mm for helical gear mounting A min shoulder of 5 mm for bearing mounting di Prop load torque 15 L 225 D Fillet radius r A min shoulder of 5 mm for bearing mounting R 30 Critical location keyway .15 200 All linear dimensions are in mm. Detailed view of the shaft