04: Torsional Stress Flashcards
What is Maximum Shearing Stress’ Components?
J - 2nd Polar Moment of Inertia (mm⁴)
d - Diameter (mm)
t - Shear Stress (MPa)
T - Torque (N × mm)
r - Radius (mm)
This is a quantity used to describe resistance to torsional deformation (deflection), in cylindrical (or non-cylindrical) objects.
2nd polar moment of inertia (J)
It is a measure of the force that can cause an object to rotate about an axis. It can be represented as the vector product of force and position vector.
Torque
What is the Equation for 2nd Polar Moment of Inertia in Solid Section Cylinder?
32 × J = π × (diameter)⁴
What is the Maximum Torsional Stress of Solid Section Cylinder?
Maximum Shearing × π × (diameter)³ = 16 × Torque
What is the Equation for 2nd Polar Moment of Inertia in Hollow Section Cylinder?
32 × J = π × [(outer diameter)⁴ - (inner diameter)⁴]
What is the Maximum Shearing Stress of Hollow Section Cylinder?
Maximum Shearing Stress × J = Torque × radius
where: radius = outer diameter ÷ 2
This is
the angular deformation in an object
due to a couple of twisting torques.
Angle of Twist
What is the Angle of Twist (in radians)?
Angle of Twist × J × Shear Modulus = Torque × Length
What is the Torsional Stiffness?
Torsional Stiffness × Length = J × Shear Modulus
or
Torque = Torsional Stiffness × Angle of Twist (in radians)
What is Torsional Rigidity?
Torsional Rigidity = Shear Modulus × J
Unit (G × m²)
What is Maximum Tensile Strength?
Maximum Stress = Maximum Tensile Stress
What is Maximum Shear Stress?
Maximum Tensile Stress = Maximum Shear Strain × Shear Modulus
or
Maximum Shear Strain = Radians
What is Power?
Power = (2 × π × number of revolutions per minute × Torque) ÷ 60
