This sheet is a very simple and quick way to calculate linear thermal expansion in typical metal piping materials. Also valid for non-piping components of the same type of materials.
Linear thermal expansion occurs when materials expand or contract as a result of temperature changes. To calculate the linear thermal expansion of a metal pipe, you'll need to know the pipe's initial length, the material's coefficient of linear thermal expansion, and the change in temperature.
The formula for linear thermal expansion is:
ΔL = L0 * α * ΔT
ΔL = Change in length due to thermal expansion (inches, mm) L0 = Initial length of the pipe (inches, mm) α = Coefficient of linear thermal expansion (inches/inch/°F, mm/mm/°C) ΔT = Change in temperature (°F, °C)
Coefficients of linear thermal expansion (α) for some typical metal piping materials are:
- Carbon steel: 6.5 x 10^-6 inches/inch/°F (11.7 x 10^-6 mm/mm/°C)
- Stainless steel: 9.6 x 10^-6 inches/inch/°F (17.3 x 10^-6 mm/mm/°C)
- Copper: 9.3 x 10^-6 inches/inch/°F (16.6 x 10^-6 mm/mm/°C)
- Aluminum: 13 x 10^-6 inches/inch/°F (23.4 x 10^-6 mm/mm/°C)
Please note that these coefficients are approximate and can vary depending on the specific alloy, manufacturing process, and temperature range.
To calculate the linear thermal expansion, follow these steps:
- Determine the initial length (L0) of the pipe.
- Determine the change in temperature (ΔT).
- Identify the coefficient of linear thermal expansion (α) for the specific metal pipe material.
- Plug the values into the formula and calculate the change in length (ΔL).
Calculate the linear thermal expansion of a 100-foot-long carbon steel pipe when the temperature increases by 50°F (28°C).
L0 = 100 ft (initial length) ΔT = 50°F (change in temperature) α = 6.5 x 10^-6 inches/inch/°F (coefficient of linear thermal expansion for carbon steel)
ΔL = L0 * α * ΔT ΔL = 100 ft * (12 inches/ft) * (6.5 x 10^-6 inches/inch/°F) * 50°F ΔL ≈ 0.39 inches
The carbon steel pipe would expand approximately 0.39 inches due to the temperature increase.
Full download access to any calculation is available to users with a paid or awarded subscription (XLC Pro).
Subscriptions are free to contributors to the site, alternatively they can be purchased.
Click here for information on subscriptions.