1. What Is Shaft Diameter Under Torsion?

The shaft diameter under torsion calculation determines the minimum diameter required for a solid circular shaft to safely transmit torque without exceeding the allowable shear stress. This is crucial in mechanical engineering design for power transmission systems.

2. How Does The Calculator Work?

The calculator uses the torsion formula for solid circular shafts:

Where:

• \( d \) — Shaft diameter (m)
• \( T \) — Applied torque (N·m)
• \( \tau \) — Allowable shear stress (Pa)
• \( \pi \) — Mathematical constant pi (approximately 3.14159)

Explanation: This formula is derived from the torsion equation for solid circular shafts, ensuring the maximum shear stress does not exceed the material's allowable limit.

3. Importance Of Shaft Diameter Calculation

Details: Proper shaft sizing is essential for mechanical system reliability, preventing failure due to torsional stress, and ensuring efficient power transmission in rotating machinery.

4. Using The Calculator

Tips: Enter torque in Newton-meters (N·m) and allowable shear stress in Pascals (Pa). Ensure both values are positive numbers for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What Is The Torsion Formula Based On?
A: The formula is derived from the torsion equation for circular shafts, considering the polar moment of inertia and maximum shear stress distribution.

Q2: What Are Typical Shear Stress Values For Common Materials?
A: Steel: 40-60 MPa, Aluminum: 20-30 MPa, Brass: 35-45 MPa. Always consult material specifications for exact values.

Q3: Does This Formula Apply To Hollow Shafts?
A: No, this formula is specifically for solid circular shafts. Hollow shafts require a different calculation considering inner and outer diameters.

Q4: What Safety Factors Should Be Considered?
A: Engineering applications typically use safety factors of 1.5 to 3.0, depending on the application criticality and load variations.

Q5: How Does Shaft Length Affect The Calculation?
A: This formula calculates diameter based on shear stress only. For long shafts, deflection and critical speed may also need consideration.