- #1
tthree
Please bear with me, I am trying to design a shaft that will be under torsion. I do not know the diameter of the shaft and I would like to be able to calculate it by the things that I do know about the system.
There's a 15HP 3 Phase motor running at 85RPM [there's a gearbox]
This will be putting out 1255Nm of torque.
I have medium carbon steal with these mechanical properties:
Mechanical Properties Metric English Comments
Hardness, Brinell 201 - 269 201 - 269
Hardness, Rockwell C 13.8 - 27.6 13.8 - 27.6
Tensile Strength, Ultimate 686 MPa 99600 psi
Tensile Strength, Yield 490 MPa 71100 psi
Elongation at Break 17 % 17 %
Reduction of Area 45 % 45 %
Modulus of Elasticity 205 GPa 29700 ksi Typical steel
Poissons Ratio 0.29 0.29 Typical steel
Machinability 55 % 55 % Based on AISI 1212 steel as 100% machinability
Shear Modulus 80.0 GPa 11600 ksi Typical steel
Impact 8.0 8.0 kg(f)/cm²
Leaving off safety factor for now, just for simplicity sake.
My question is; can I calculate the the diameter of the shaft based on the above information? What I can say so far is:
T = 1.255x10^6Nmm
G = 80GPa
Hz = 1.42
RPM = 85
If so how can I do it?
There's a 15HP 3 Phase motor running at 85RPM [there's a gearbox]
This will be putting out 1255Nm of torque.
I have medium carbon steal with these mechanical properties:
Mechanical Properties Metric English Comments
Hardness, Brinell 201 - 269 201 - 269
Hardness, Rockwell C 13.8 - 27.6 13.8 - 27.6
Tensile Strength, Ultimate 686 MPa 99600 psi
Tensile Strength, Yield 490 MPa 71100 psi
Elongation at Break 17 % 17 %
Reduction of Area 45 % 45 %
Modulus of Elasticity 205 GPa 29700 ksi Typical steel
Poissons Ratio 0.29 0.29 Typical steel
Machinability 55 % 55 % Based on AISI 1212 steel as 100% machinability
Shear Modulus 80.0 GPa 11600 ksi Typical steel
Impact 8.0 8.0 kg(f)/cm²
Leaving off safety factor for now, just for simplicity sake.
My question is; can I calculate the the diameter of the shaft based on the above information? What I can say so far is:
T = 1.255x10^6Nmm
G = 80GPa
Hz = 1.42
RPM = 85
If so how can I do it?