District Heating > How a heat supply network operates  

How a heat supply network operates

In a heat supply network, thermal energy can be transported many kilometres by a producer to a consumer. Transport of this heat energy ensues via strongly insulated piping systems.

Purified water is generally used as a formation fluid, due to its roughly specific heat capacity. Hot water is transported to the consumer via the flow line. There, heat is extracted from the water through a heat exchanger and the water stays in the pipes. The cooled water then flows back to the heat generator via the return line, where it is once again heated. The heat supply network therefore constitutes a closed cycle system.

Pre-insulated pipes are exclusively used for such a piping system. This means that the insulation has already been provided by the manufacturer of the pipes and they only need to be installed on site. It has been shown that this has resulted in a reduction of manufacturing and installation costs as well as an improvement in the level of insulation and the effectiveness of the heat supply network.

Pipes with an outer casing of polyethylene (PE) and insulation of polyurethane rigid foam (PUR) have proven to be the best technical and economical choice in this case. Combined with a long service life and long-term maintenance-free use of the pipes, in addition to cost-efficient installation on a bed of sand, the operation of expansive networks is made possible.

The exact configuration of the pipes varies according to the temperature of the water and the on-site requirements. Within a range of up to 140°C, rigid pre-insulated pipes are mostly used.

For low temperatures, flexible piping systems, which are delivered on reels, can be used as an alternative in order to save on investment costs. As an example, flexible pipes can be used as a medium pipe made from one of the following materials:

isoplus have been producing pre-insulated pipes in the most modern of production facilities for over thirty-five years and are one of the leading manufacturers in Europe.

Our expertise is complemented by a comprehensive range of services. This has made isoplus a reliable partner in business to many companies in Europe.