NEWS

Introduction to Polyurethane Insulated Steel Pipe

Release time:

2023-06-26 14:21

Polyurethane insulated steel pipes, also known as insulated direct buried pipes, are divided into outer polyethylene inner polyurethane insulated pipes, steel sleeve steel insulated pipes, outer iron sheet inner polyurethane insulated pipes. They are made of outer and inner polyurethane to provide insulation for the liquid conveyed by the steel pipes.

Construction characteristics

1. Reduce project costs

According to relevant departments' calculations, the dual pipe heating pipeline can generally reduce project costs by about 25% and 10%.

2. Low heat loss and energy conservation

The thermal conductivity of high-temperature prefabricated directly buried insulation pipes is: λ= 0.013-0.03kcalm · h · oC, which is much lower than other commonly used pipeline insulation materials in the past and has a good insulation effect. Moreover, its water absorption rate is very low, about 0.2kgm2.

The reason for low water absorption is that the closed cell rate of polyurethane foam is up to 92%. The low thermal conductivity and low water absorption, combined with the insulation layer and high-density polyethylene or fiberglass protective shell with good waterproof performance on the outside, have changed the traditional "wet cotton jacket" situation of heating pipelines laid in trenches, greatly reducing the overall heat loss of heating pipelines. The heat loss of the heating network is 2%, which is less than the international standard requirement of 10%.

3. Anti corrosion, good insulation performance, and long service life

Due to the polyurethane insulation layer tightly bonded to the outer surface of the steel pipe, high-temperature prefabricated directly buried insulation pipes isolate the infiltration of air and water, and can play a good anti-corrosion role. At the same time, its foam pores are all closed, and its water absorption is very small. The high-density polyethylene shell and fiberglass shell both have good anti-corrosion performance. Therefore, the outer skin of the working steel pipe is difficult to be corroded by external air and water.