External Load on Bolt due to Internal Pressure given kb and kc Calculator

External Load Formula:

\[ P_{ext} = \Delta P_i \times \left( \frac{k_c + k_b}{k_b} \right) \]

Increase in Bolt Load (ΔPi):

Combined Stiffness (kc):

N/m

Bolt Stiffness (kb):

N/m

Tolerance:

External Load (Pext): N

1. What is External Load on Bolt due to Internal Pressure?

Definition: This calculator determines the external load acting on a pressurized cylinder bolt based on the increase in bolt load, combined stiffness of the joint, and bolt stiffness.

Purpose: It helps mechanical engineers and designers calculate the additional load on bolts due to internal pressure in pressurized systems.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ P_{ext} = \Delta P_i \times \left( \frac{k_c + k_b}{k_b} \right) \]

Where:

\( P_{ext} \) — External load on bolt (N)
\( \Delta P_i \) — Increase in bolt load (N)
\( k_c \) — Combined stiffness of joint (N/m)
\( k_b \) — Stiffness of bolt (N/m)

Explanation: The formula accounts for how the internal pressure affects the bolt load through the stiffness ratio of the joint and bolt.

3. Importance of External Load Calculation

Details: Accurate calculation ensures proper bolt sizing, prevents joint failure, and maintains pressure integrity in pressurized systems.

4. Using the Calculator

Tips: Enter the increase in bolt load (ΔPi), combined stiffness (kc), bolt stiffness (kb), and optional tolerance percentage. All stiffness values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is typical bolt stiffness range?
A: Bolt stiffness typically ranges from 1×10⁶ to 1×10⁹ N/m depending on size and material.

Q2: How is combined stiffness determined?
A: Combined stiffness includes cylinder cover, flange, and gasket stiffness values in series.

Q3: Why include a tolerance percentage?
A: Tolerance accounts for material variations and safety factors (±5% is common).

Q4: How does internal pressure affect bolt load?
A: Internal pressure creates additional tensile load on bolts through the stiffness ratio.

Q5: What units should be used?
A: Use consistent units - Newtons (N) for loads and Newtons/meter (N/m) for stiffness.