New possibilities for thermal cycling testing
In district heating, plastic jacket pipes are mostly used in the distribution networks. These are designed for transporting hot water at 120 °C permanently and up to 140 °C for short periods. In the case of plastic casing pipes, the carrier pipe, among other things, is made of steel due to its temperature resistance. These steel pipes are welded together. In addition to the conventional material-to-material connection, i.e. welding, mechanical connection systems are now also being used, especially in the smaller nominal diameter range (DN20 -DN100).
In general, the materials used for district heating networks have evolved: In addition to the classic steel service pipe, plastic pipe systems are now being used more and more frequently. These must then permanently withstand temperatures of up to 80 °and up to 95 °C at peak. Applus+ IMA Dresden is involved in the standardization of new types of products, including new test procedures, to enable the necessary qualifications and certifications. Latest developments lead to continuous operating temperatures of 90 °C and short-term temperatures of up to 115 °C for plastic pipe systems.
And this is exactly what the pipe system experts at Applus+ IMA Dresden can now test. For this purpose, a new and unique test facility has been put into operation which can now perform thermal cycling tests between 20 and 140 °C (previously maximum 95 °C). The new test facility also covers a maximum pressure range of 25 bar (previously 10 bar), so that the system suitability and durability of the mechanical or force-locking connections can also be verified for the plastic casing pipe systems already mentioned.