Thermal Expansion Calculator
How much a bar, rail or pipe grows when its temperature rises.
Results
Elongation
5.7600
mm
Length
12.005760
m
What this tool does
Coefficients are entered in millionths per kelvin: about 12 for steel, 23 for aluminium, 17 for copper and 10 for concrete. A twelve-metre steel beam warming by forty degrees grows almost six millimetres, which is exactly why expansion joints exist.
Formula
ΔL = α × L₀ × ΔT
Variables
| Symbol | Meaning | Unit |
|---|---|---|
l | Original length | m |
al | Ratio | 1/K ×10⁻⁶ |
dt | Temperature change | K |
DL | Elongation | mm |
LF | Length | m |
Worked example
- Original length12 m
- Ratio12 1/K ×10⁻⁶
- Temperature change40 K
- Elongation5.7600 mm
- Length12.005760 m
Limitations
- For work that must comply with a standard or be signed off, check the result against the applicable code and have it reviewed by a qualified engineer.
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.