Reasons for the widespread use of pre-fabricated directly-buried insulation pipes

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This post was last edited by Direct-Buried Insulated Pipes on 2015-10-13 at 14:26. Reasons for the widespread use of prefabricated direct-buried insulated pipes: 1. Reducing project costs – For double-pipe heating systems, this can reduce project costs by around 25% when a fiberglass coating is used, and by about 10% when a high-density polyethylene coating is used. 　　2. It has low heat loss, thus saving energy. The thermal conductivity of high-temperature pre-fabricated directly-buried insulation pipes is λ=0.013–0.03 kcal/m·h·°C, which is much lower than that of other insulation materials commonly used in the past; as a result, the insulation efficiency is improved by 4 to 9 times. Furthermore, its water absorption rate is very low, at around 0.2 kg/m2. The low water absorption rate is due to the high closed-cell content of the polyurethane foam, which is around 92%. The low thermal conductivity and low water absorption, combined with an insulating layer and a high-density polyethylene or fiberglass protective shell with excellent waterproof properties, change the situation in which heating pipes laid in traditional trenches are like being wrapped in wet cotton coats. This reduces the overall heat loss of the heating pipes; the heat loss in the heating network is 2%, which is less than the international standard of 10%. 3. Polyurethane insulation pipes have good corrosion resistance, excellent insulating properties, and a long service life. Buried insulation pipes provide excellent corrosion protection, as the rigid polyurethane foam insulation layer adheres tightly to the outer surface of the steel pipe, preventing the infiltration of air and water. Pre-fabricated directly-buried insulated pipes have their foam pores closed, resulting in very low water absorption. High-density polyethylene housings, fiberglass-reinforced plastic, and polyurethane foam insulation pipe housings all possess excellent corrosion resistance, insulation properties, and mechanical strength. Therefore, the outer surface of the working steel pipe is hardly susceptible to erosion by external air and water. As long as the water quality inside the pipe is properly managed, steel-clad steel steam insulation pipes can maintain their performance effectively. According to foreign sources, polyurethane insulation pipes have a service life of over 50 years, which is 3 to 4 times longer than that of traditional pipes laid in trenches or installed in an overhead manner by manufacturers. 4. Foreign manufacturers of polyurethane-insulated prefabricated pipes, as well as those who produce pipes for underground installation, equip these pipes with leak detection systems; should a leak occur somewhere in the pipe, it is detected through these detection systems. This allows the precise location of water seepage or leaks in the insulated pipes, as well as the extent of the leakage, to be displayed on specialized testing instruments. This enables the personnel responsible for detecting leaks to address the problematic sections promptly, thereby ensuring the safe operation of the heating pipeline network.