A New Type of Pre-Insulated Bonded Pipe

The present paper introduces the structural form of PE-RT pre-insulated pipes (PE-RT used as service pipes) for use as a substitute for steel pre-insulated pipes (steel pipe used as service pipes). The technical advantages of the PE-RT pre-insulated pipes when used in district heating are also illustrated. For pipes with the same diameter, length, and flow-rate, the pressure drop and transportation energy consumption for both steel pre-insulated pipes and PE-RT pre-insulated pipes are analyzed. If PE-RT pre-insulated pipes are used in the secondary network of Taiyuan (capital city of Shanxi, China) district heating, up to 10.44 million kilowatt-hours of energy could be saved at the circulating pump in only one heating period. If implemented throughout the country, 0.44 billion kilowatt-hours (equivalent to 54 thousand tons of standard coal) could be saved. In addition, the change could reduce the emission of CO₂ by about 135,000 tons, SO₂ by about 3,240 tons, and N_xO by 2,030 tons. Moreover, the yearly share expenses of PE-RT pre-insulated systems are much lower than those of steel pre-insulated systems in their service life.