Pipeline insulation is widely used in liquid and gas transmission pipeline network, chemical pipeline insulation engineering petroleum, chemical industry, central heating pipeline network, central air conditioning ventilation pipeline, municipal engineering and so on. High-temperature prefabricated directly buried thermal insulation pipe is a kind of directly buried prefabricated thermal insulation pipe with good thermal insulation performance, safe and reliable heating and low engineering cost. It effectively solves the problems of heat preservation, sliding lubrication and waterproofing of exposed pipe ends of prefabricated directly buried heat preservation pipes for high-temperature heat transfer in urban central heating 130℃-600℃. High-temperature prefabricated directly buried insulation pipe not only has advanced technology and practical performance that traditional trench and overhead laying pipeline can't match, but also has remarkable social and economic benefits, and is also a powerful measure for heating and energy saving. The high-temperature prefabricated directly buried insulation pipe adopts directly buried heating pipeline technology, which indicates that the development of heating pipeline technology in China has entered a new starting point.
Thermal insulation materials for pipelines mainly include: rock wool, high temperature resistant glass wool, aluminum silicate, microporous calcium silicate, composite silicate, pipeline bracket, heat shrinkable tape, polyurethane composition, etc.
The following are the technical indicators of several main auxiliary materials:
1, numerical volume density of aluminum silicate technical index project 80- 130 operating temperature
2. Standard numerical density of high temperature resistant glass wool technical index project GB5480.3- 1985 50-80 Operating temperature GB11835-89-120-400 Thermal load contraction temperature GB/T10294 50.
3. The technical index of microporous calcium silicate is 170-270, the compressive strength is 0.40-0.80, the flexural strength is 0.20-0.30, the maximum service temperature is 1000- 1050, and the thermal conductivity is 0.048-0.056.
1, reducing the project cost. According to the calculation of Hebei Juqing Pipeline and relevant departments, the double-pipe heating pipeline can generally reduce the project cost by about 25% (using FRP as protective layer) and 10% (using high-density polyethylene as protective layer).
2. Low heat loss and energy saving.