Rubber and plastic foam cold insulation and plastic coated steel pipes for overhead cold insulation pipes are mainly used for pipes below normal temperature. By covering the outside with cold insulation materials, the transmission of external heat to the inside of the pipe is reduced, and the surface temperature is kept above the dew point, so as to prevent external surface condensation. This measure not only helps to maintain the temperature stability of the medium inside the pipeline, avoid condensation or freezing, but also reduces energy loss to a certain extent