Sizing & Pipe Expansion – Aquatechnik UK

Sizing & Expansion

Sizes available:

Aquatechnik’s Multi-layer pipe is available in lengths (4m) and coils (50m and 100m) in sizes:

16mm, 20mm, 26mm, 32mm, 40mm, 50mm, 63mm & 75mm

Expansion:

Any pipe, whether manufactured in plastic or metal, elongates when the temperature of the conveyed fluid increases (linear thermal expansion). Linear expansion creates mechanical stresses that may damage the system if not adequately contained.

Polymeric pipe has a greater linear thermal expansion than metallic, but they develop lower mechanical stress. The beauty of multi-layer pipe is that it behaves very similarly to its metal counterpart with it being a plastic-metal composition. The intermediate adhesives that bind the multi-layer pipe impose the elongation of the aluminium to the plastic layers, ensuring the linear thermal expansion behaves similarly to that of metal pipe.

Linear thermal expansion is calculated using the following formula:

DL = expansion (mm)

a = coefficient of linear thermal expansion (see table below)

L = length of pipeline (m)

Dt = change in temperature (°C)

For a handy reference, refer to the table to the left. It shows the linear thermal expansion values for pipes with lengths between 0.5 and 10 linear metres, with Dt between 10 and 80°C for the Aquatechnik multi-layer pipe range.

Clamping of pipe

When compared with other multi-layer systems, the pipe expansion benefits of Aquatechnik often improve clamping distances. The table to the left highlights the spacing required at different temperatures.