# Steel Pipes - Calculating Thermal Expansion Loops

## Calculating and sizing steel pipe thermal expansion loops.

The expansion loop is a common way to absorb temperature expansion and contraction in steel pipes. Expansion loops can be fabricated from standard pipes and elbows.

Approximate Expansion Capacity (mm) | |||||
---|---|---|---|---|---|

Nominal Pipe Size (mm) | Width of Expansion Loop - w - (m) | ||||

0.5 | 1.0 | 1.5 | 2.0 | 2.5 | |

25 | 35 | 130 | |||

32 | 25 | 100 | 210 | ||

40 | 20 | 70 | 150 | ||

50 | 65 | 125 | 200 | ||

65 | 50 | 100 | 150 | 220 | |

80 | 40 | 75 | 125 | 190 | |

100 | 35 | 65 | 115 | 150 | |

### U-Bends Expansion Compensator Calculator

#### Metric Units

This calculator can be used to calculate required width and height of an U-bends expansions compensator.

*S - Length of expanding pipe (m)*

* Expansion coefficient (10 ^{-6} m/m ^{o}C) *

* Initial temperature ( ^{o}C)*

* Final temperature ( ^{o}C)*

* Outside diameter of pipe (mm)*

#### Imperial Units

*S - Length of expanding pipe (ft)*

* Expansion coefficient (10 ^{-6} in/in ^{o}F) *

* Initial temperature ( ^{o}F)*

* Final temperature ( ^{o}F)*

* Outside diameter of pipe (in)*

The U-loops calculation is based on equation

*w = 0.015 (dl D) ^{1/2} (1)*

*where *

*w = width of loop (m)*

*dl = α dt S = temperature expansion (m)*

*α = temperature expansion coefficient (m/m ^{o}C)*

*dt = temperature change ( ^{o}C)*

*S = length of expanding pipe (m)*

*D = diameter of pipe (m)*

The offset of the loop is *2 w*. The length of the loop is *5 w.*

### Z-Bends Expansion Compensator Calculator

#### Metric Units

This calculator can be used to calculate required offset in a Z-bends expansions compensator.

*S - Length of expanding pipe (m)*

* Expansion coefficient (10 ^{-6} m/m ^{o}C) *

* Initial temperature ( ^{o}C)*

* Final temperature ( ^{o}C)*

* Outside diameter of pipe (mm)*

#### Imperial Units

*S - Length of expanding pipe (ft)*

* Expansion coefficient (10 ^{-6} in/in ^{o}F) *

* Initial temperature ( ^{o}F)*

* Final temperature ( ^{o}F)*

* Outside diameter of pipe (in)*

### L-Bends Expansion Compensator Calculator

#### Metric Units

This calculator can be used to calculate required offset in a Z-bends expansions compensator.

*S _{max} - Length of longest expanding leg (m)*

* Expansion coefficient (10 ^{-6} m/m ^{o}C) *

* Initial temperature ( ^{o}C)*

* Final temperature ( ^{o}C)*

* Outside diameter of pipe (mm)*

#### Imperial Units

This calculator can be used to calculate required offset in a Z-bends expansions compensator.

*S _{max} - Length of longest expanding leg (ft)*

* Expansion coefficient (10 ^{-6} in/in ^{o}F) *

* Initial temperature ( ^{o}F)*

* Final temperature ( ^{o}F)*

* Outside diameter of pipe (in)*

The L-loop calculation is based on equation

*L = 0.063 (dl D) ^{1/2} (2)*

*where *

*L = length of loop (m)*