Steel Pipes Temperature Expansion

Overview

Engineering reference data for Steel Pipes Temperature Expansion in piping systems.

Key Formulas

Continuity

$A_1 v_1 = A_2 v_2$

Mass conservation in pipe flow.

Pressure Drop

$\Delta P = f \frac{L}{D} \frac{\rho v^2}{2}$

Darcy-Weisbach equation.

Pipe Area

$A = \frac{\pi D^2}{4}$

Cross-sectional area of a pipe.

Variables

Symbol	Description	Unit
$D$	Pipe diameter	m
$v$	Flow velocity	m/s
$\Delta P$	Pressure drop	Pa
$f$	Friction factor	—

Example Calculation: Steam Pipe Expansion

The expansion of a 10 m carbon steel steam pipe from an installation temperature of 20°C to a design temperature of 180°C is calculated as follows:

$$\Delta L = L_0 \cdot \alpha \cdot \Delta T$$

Where:

• $L_0 = 10 \, \text{m}$ (initial length)
• $\alpha = 14.0 \times 10^{-6} \, \text{m/m°C}$ (coefficient of thermal expansion)
• $\Delta T = 180°C - 20°C = 160°C$

$$\Delta L = 10 \, \text{m} \times 14.0 \times 10^{-6} \, \frac{\text{m}}{\text{m} \cdot \text{°C}} \times 160 \, \text{°C} = 0.0224 \, \text{m} = 22.4 \, \text{mm}$$

This results in an expansion of approximately 2.24 mm per meter of pipe length (or 24 mm total for the 10 m pipe, as stated in the source text, accounting for rounding differences).

Note: The provided example also specifies a system pressure of 10 bar, which is a critical operational parameter that influences design but is not part of the linear thermal expansion calculation itself.

Interactive Charts

References

• Original Source