1. As buried pipelines, insulation must be carried out when the buried depth exceeds the freezing line.
2. When the steel wire mesh skeleton composite pipe is buried in the frozen soil area, insulation measures must be taken, and the buried depth is not less than 0.5m. When crossing the road, the buried depth must be greater than 0.8m.
Three, when the steel wire mesh skeleton composite pipe in the indoor and outdoor laying, it is likely to freeze, insulation measures should be taken.
4. When the hot water pipe is plainly applied or not directly buried, it should be kept warm. At the same time, steel wire mesh skeleton composite pipe conveying water temperature is not higher than 45℃. When pipes may condense and affect the environment, an anti-condensation insulation layer should be installed.
Five, when the steel wire mesh skeleton composite pipe needs heat preservation, should be based on the length of the pipeline, water temperature, environmental temperature, water supply time and the performance of the insulation material, accurate calculation, determine the thickness of the insulation material layer.
Matters needing attention:
The operating temperature of hot water pipe is low, the heat loss is small, and the heat capacity of water is large, so the temperature drop of hot water is small, and generally not calculated according to the allowed temperature drop condition. When the nominal outer diameter of PSP pipe is greater than or equal to 315mm, it is recommended to calculate large heat loss.
When the insulation layer occupies a large proportion in an investment or the process allows, the insulation layer thickness can be calculated according to the allowable temperature drop. At this point, the insulation layer thickness of steel wire mesh skeleton plastic composite pipe is slightly less than that of steel pipe, but it should be checked whether the heat loss is in line with the provisions of GB4272;
For outdoor laying and seasonal operation, the outdoor ambient temperature Ta is the average of the daily average temperature over the years. When the process is required, take the external ambient temperature Ta according to adverse conditions.
Directly buried in the soil, when the buried depth of the pipe center is greater than two times of the pipe insulation outer diameter, the ambient temperature is the natural temperature of the soil buried deep in the pipe center; When the buried depth of the center of the pipe is less than two times of the insulation diameter of the pipe, the ambient temperature can be used as the natural temperature of the surface soil. It is recommended that the pipeline be buried more than 4 times of the outer diameter of the insulation layer.
