THERMAL EXPANSION IN PPR PIPES

Thermal expansion in PP-R (Polypropylene Random Copolymer) pipes, including Glassfiber reinforced and Aluminium foil reinforced types, is a crucial aspect of their application in plumbing systems. PP-R pipes, like all plastic pipes, are subject to more significant expansion and contraction due to temperature changes compared to metal pipes. The linear thermal expansion coefficient (α) for standard PPR pipes is 0.15mm/m?°K .

This coefficient means that for every degree Celsius change in temperature, a meter of PP-R pipe will expand or contract by 0.15 mm.

The formula to calculate thermal expansion is:

ΔL=L×α×ΔT

Where:

ΔL = Change in length (mm)

L = Original length of the pipe (m)

α = Linear expansion coefficient? (0.15 mm/m ?°K?for PP-R)

ΔT = Temperature change (°C "Celsius" or?°K "Kelvin"?)

However, for Glassfiber reinforced and Aluminium foil reinforced PP-R pipes, the thermal expansion is significantly reduced due to the added materials:

Glassfiber Reinforced PPR Pipes: The addition of glass fibers reduces the linear expansion coefficient, improving dimensional stability under temperature changes. This makes them more suitable for hot water lines where temperature variations are significant. (α = 0.035 mm/m ?°K)

Aluminium Foil Reinforced PPR Pipes: These pipes have an aluminium layer, which greatly reduces thermal expansion. The aluminium layer acts as a barrier, improving the pipe's strength and reducing expansion and contraction. They are ideal for systems requiring high dimensional stability. (α = 0.030 mm/m ?°K)