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Bolt Size Formula:
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The bolt size formula calculates the minimum required bolt diameter based on applied torque and material shear stress. This ensures bolts are properly sized to withstand mechanical loads without failure.
The calculator uses the bolt size formula:
Where:
Explanation: The formula calculates the minimum bolt diameter required to safely transmit the applied torque without exceeding the material's shear stress limit.
Details: Proper bolt sizing is critical for structural integrity, safety, and reliability in mechanical systems. Undersized bolts can lead to catastrophic failures, while oversized bolts add unnecessary weight and cost.
Tips: Enter torque in Newton-meters (Nm) and shear stress in Pascals (Pa). Both values must be positive numbers. The result will be the minimum required bolt diameter in meters.
Q1: What units should I use for this calculation?
A: Use consistent SI units: torque in Newton-meters (Nm), shear stress in Pascals (Pa), and the result will be in meters (m).
Q2: How do I determine the appropriate shear stress value?
A: Shear stress depends on the bolt material. Consult material specifications or engineering handbooks for appropriate values based on your application.
Q3: Does this formula account for safety factors?
A: No, this formula provides the theoretical minimum diameter. Always apply appropriate safety factors based on your specific application requirements.
Q4: Can I use this for both metric and imperial bolts?
A: The formula is unit-agnostic, but you must maintain unit consistency. Convert all inputs to consistent units before calculation.
Q5: What other factors should I consider when selecting bolts?
A: Consider thread type, material compatibility, environmental conditions, preload requirements, and installation method in addition to diameter.