Ostrovsky Dmitry, Shmelev Andrey
Papers # 2016 Berlin
Pre-insulated thermoplastic reinforced pipes were developed for East European heating networks with elevated operating temperatures and pressures. In contrast to monolayer plastic pipes, high modulus aramid mesh reinforcement used in thermoplastic reinforced pipes allows significantly to increase both operating temperature and pressure without pipe wall thickness increase. This made it possible to develop unique flexible pre-insulated heating pipes with up to 16 Bar operating pressure and up to 100˚C continuous operating temperature fora a range of service pipe diameters from 25 mm to 160 mm. Enveloped application boundaries of pre-insulated thermoplastic reinforced pipes open new potential market for plastic pre-insulated heating pipes, as only steel pre-insulated pipes could operate with such conditions previously.
Worldwide growing demand in high efficiency energy consumption requires wider coverage of District Heating (DH) – centralized heating of buildings connected to joint pipeline network. Flexible pre-insulated plastic pipes have proven track record in DH networks due to their high reliability and ease of use. However, conventional DH plastic pipes cannot be widely used in large City Heat (CH) networks with a big amount of connected buildings due to their application limits in working temperatures, pressures and maximum coilable diameters caused by mono-layer structure of plastic service pipes. Remaining up-to-date with polymer technology evolution, plastic pipes for DH networks have been significantly developed during the last 20 years. Thermoplastic Reinforced Service (TRS) pipes can rightly be considered as the most important step of DH plastic pipes evolution. Reinforced concept with use of high modulus Aramid mesh combined with multilayer structure consist of modern polymer materials allowed for pre-insulated plastic pipes significantly increase both operating pressures up to 16 Bar and continuous operating temperatures up to 100˚C for the whole range of coilable diameters from 25 mm to up to 160 mm. This significant change made it possible to implement all the benefits of flexible pre-insulated plastic pipes to CH networks, where only rigid preinsulated steel pipes could operate before.