1. What is Flange Bolt Torque?

Flange bolt torque is the amount of rotational force applied to a bolt to achieve proper clamping force in a flange connection. Proper torque is critical for creating leak-proof seals in piping systems.

2. How Does the Calculator Work?

The calculator uses the flange bolt torque equation:

Where:

• \( Clamp\ Load \) — Desired clamping force (pounds)
• \( Diameter \) — Bolt diameter (inches)
• \( K \) — Torque coefficient (dimensionless)
• 12 — Conversion factor to ft-lb

Explanation: The equation calculates the torque needed to achieve a specific clamping force based on bolt size and friction characteristics.

3. Importance of Proper Torque

Details: Correct bolt torque ensures proper sealing without damaging flanges or bolts. Under-torque can cause leaks while over-torque can damage threads or cause bolt failure.

4. Using the Calculator

Tips: Enter clamp load in pounds, diameter in inches, and K factor (typically 0.15-0.25 for lubricated bolts). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical K factor value?
A: For dry, unlubricated bolts, K is typically 0.2. For lubricated bolts, K can range from 0.15 to 0.18.

Q2: How does bolt material affect torque?
A: Different materials have different friction coefficients which affect the K factor. Always use manufacturer-recommended values.

Q3: Why is torque measured in ft-lb?
A: Foot-pounds is the standard unit for torque in imperial systems, representing rotational force.

Q4: Should I use this for critical applications?
A: For critical flanges, always follow specific engineering specifications and procedures.

Q5: How often should torque be checked?
A: In critical applications, torque should be verified after initial assembly and periodically during service.