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Bolt Torque to Clamping Force Formula:
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The bolt torque to clamping force formula calculates the clamping force generated by a bolt when a specific torque is applied. This relationship is fundamental in mechanical engineering for designing bolted joints and ensuring proper fastening.
The calculator uses the formula:
Where:
Explanation: The formula shows that clamping force is directly proportional to the applied torque and inversely proportional to both the torque coefficient and bolt diameter.
Details: Accurate clamping force calculation is crucial for ensuring joint integrity, preventing bolt failure, and maintaining proper sealing in mechanical assemblies. Under-torquing can lead to joint separation, while over-torquing can cause bolt stretching or failure.
Tips: Enter torque in Newton-meters (Nm), torque coefficient (typically between 0.15-0.25 for standard bolts), and bolt diameter in meters. All values must be positive numbers.
Q1: What is a typical torque coefficient (K) value?
A: For standard unlubricated steel bolts, K is typically between 0.15-0.25. Lubricated bolts may have values as low as 0.10.
Q2: Why does bolt diameter affect clamping force?
A: Larger diameter bolts have a greater lever arm, meaning less force is generated for the same applied torque compared to smaller diameter bolts.
Q3: How accurate is this calculation?
A: The calculation provides a theoretical estimate. Actual clamping force can vary due to factors like surface finish, lubrication, and thread condition.
Q4: Can this formula be used for all bolt types?
A: While the basic relationship holds for most bolts, specialized fasteners may have different torque-tension relationships that require manufacturer-specific formulas.
Q5: What units should I use for this calculation?
A: Use consistent SI units: torque in Newton-meters (Nm), diameter in meters (m), which will give force in Newtons (N).