The application of PERT pipes in building hot and cold water piping in my country has developed rapidly, and the raw materials have also seen further development. In 2002, the industry standard "Heat-resistant Polyethylene (PE-RT) Piping Systems for Hot and Cold Water" was published. However, at that time, the industry standard referenced the German standards "Heat-resistant Polyethylene (PE-RT) Piping – General Quality Requirements" and "Heat-resistant Polyethylene (PE-RT) Piping – Dimensions," both of which were based on the performance indicators of Type I PE-RT materials. With the development of materials, the performance indicators of Type II PE-RT materials are now far superior to those of the first generation. The international standard ISO 22391 "Heat-resistant Polyethylene (PE-RT) Piping Systems for Hot and Cold Water" has also been revised and updated, adding requirements for Type II PE-RT pipes.
With the development of materials, PE-RT pipes have been upgraded to PE-RT Type II pipes, which are divided into three types according to their different comonomers:
1. Ethylene and octene copolymer - heat-resistant polyethylene (C2+C8);
2. Ethylene and hexene copolymer - heat-resistant polyethylene (C2+C6);
3. Ethylene and butene copolymer - heat-resistant polyethylene (C2+C4)
The newly launched (PE-RT Type II pipe) material is suitable for industrial and civil building hot and cold water piping systems, drinking water systems, pre-buried heating pipes, floor radiant heating systems, and high-temperature ground source heat pump systems, especially in northern regions where it is used in secondary pipe networks of urban heating systems - PE-RT Type II prefabricated direct-buried insulated pipes.
