Outdoors Installations - UV Resistance

Use of plastic pipes outdoors, on roof-tops, for example, has many advantages to end-user and contractors alike. Plastics low weight and quick jointing make it ideal for outdoor or roof-top installations.
It is important to ensure a low stress installation and pipe routing. GF has tested PE-100 black pipe under simulated extreme outdoor conditions. The test conditioons simulate extreme day-night and winter-summer environmental conditions, as well as direct sunlight, respectively also direct UV-light. The testing focussed on measuring the amount of linear movement of plastic pipe under direct sunlight and weathering conditons. The data accumulated can then be used to ensure that the layout of the pipeline takes this linear movement into account, ensuing a stress free complete installation.  

External Commissioned Report : IKKU Karlsruhe Institute for Air-Conditioning and Refrigeration
The complete report is available for customers who would like to understand in detail the movement of plastic pipes under direct sunlight.

The conclusions are as follows:

• The results show that direct solar effect has no influence on the standard expansion and/or contraction of COOL-FIT
• There was no measurable extra movement in the COOL-FIT pipe under the solar lamps
• The COOL-FIT pipe remains homogenous (ie no breaking of the bond between PE-PUR-PE)
• The results have confirmed the theoretical assumptions made in the GF internal expansion calculation program, namely that to simulate solar gain outdoors use of maximum ambient air temperature as a variable is the best mathematical methodology  
• The results are being integrated into our in-house and customer available calculation tools. At lower operating temperatures (<0°C) the differences between theoretical and practical results (~20% delta) have been incorporated. Tests have shown that the material expansion coefficients reduce at lower temperatures, hence leading to less expansion than initially anticipated
• GF has an in-house calculation tool (COOLING Tool-Box) to calculate exactly expansion / contraction of  all plastic pipes under given set conditions. This tool is available free-of-charge via the GF homepage

GF recommends use of PE black, namely the ecoFIT system, for outdoor instalaltions under the effect of weathering and UV light. PE black contains TiO2, black pigment, which gives the raw material an inherent UV resistance and direct exposure to other weatheirng conditions, for example wind, rain, temperature fluctuatons, will have no negative effect on the raw material and pipe system.
The test results shown below, show that the quality of the pipe after 18 years of operation outdoors show no signiifcant difference to original pipe.