The possibility to detect potential leakage in a DH (or LTDH) system is crucial. Leakage reduces the insulating ability of the foam in the pipes. Leakage from the media pipe will also eventually find its way out of the casing and might undermine the ground. In COOL DH, plastic media pipes are used instead of the classic steel media pipes. This requires a slightly different solution to detect leakage.
New type of PE-RT pipes
The PE-RT (Poly Ethylene Raised Temperatures) pipes developed, and used in the project in Brunnshög, have been equipped with a special solution for moisture detection. This solution enables the use of plastic pipes in a District Heating system, and furthermore lower the cost for reparations as well as lower the risk of damage of the surrounding ground. The leakage detection cable in PE-RT pipes include a third alarm wire, complementing the usual pair of copper wires in ordinary district heating pipes with steel or copper media pipe. The third wire is replacing the electric conductivity of the steel pipes that the plastic pipes lack.
From the inside out, the developed PE-RT pipes with leakage detection consists of:
- Media pipe, PE-RT
- Diffusion barrier, aluminum foil
- PE-RT protection layer
- PUR Insulation
- Leakage detection, 3- wire leakage detection cable
- Outer casing with diffusion barrier
If you are interested in learning more about the new type of PE-RT pipes, please contact:
Anders Jirdén, Project Manager at Kraftringen