Change in External Load on Bolt due to Pressure Inside Cylinder Calculator

Formula:

\[ \Delta P_i = P_b - P_l \]

Resultant load on pressurized cylinder bolt:

Initial Preload Due to Bolt Tightening:

Tolerance:

Increase in Bolt Load of Cylinder (ΔPi):

1. What is Change in External Load on Bolt?

Definition: This calculator determines the variation in bolt load caused by internal pressure in a cylinder, accounting for initial preload.

Purpose: It helps engineers analyze how internal pressure affects bolt loading in pressurized systems.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ \Delta P_i = P_b - P_l \]

Where:

\( \Delta P_i \) — Increase in bolt load (N)
\( P_b \) — Resultant load on bolt under pressure (N)
\( P_l \) — Initial preload from bolt tightening (N)

Explanation: The change in bolt load is the difference between the loaded and preloaded states.

3. Importance of This Calculation

Details: Proper bolt load analysis prevents joint failure, maintains sealing integrity, and ensures safety in pressurized systems.

4. Using the Calculator

Tips: Enter the resultant bolt load, initial preload, and tolerance percentage (default ±5%). All values must be ≥ 0.

5. Frequently Asked Questions (FAQ)

Q1: Why include a tolerance percentage?
A: Tolerance accounts for measurement uncertainties and material variations in real-world applications.

Q2: What's a typical preload value?
A: Preload is typically 60-75% of bolt proof load, but consult engineering standards for specific applications.

Q3: When would this calculation be negative?
A: If internal pressure reduces bolt load below preload, indicating joint separation risk.

Q4: How is resultant bolt load determined?
A: Through pressure-area calculations or direct measurement in tested assemblies.

Q5: Does this account for gasket compression?
A: No, for gasketed joints, additional calculations for gasket behavior are needed.