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 NxO 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.