Prefabricated directly buried heat preservation pipe is a steel pipe which is processed by heat preservation technology and ensures that the internal temperature and surface temperature of the working steel pipe meet or meet the service requirements under the action of different working environments and external media.

Insulation pipe is widely used in liquid and gas transmission network, chemical pipeline heat preservation engineering, petroleum, chemical, central heating heating network, central air conditioning and ventilation pipeline, municipal engineering, etc.

Underground polyurethane foam insulation pipe

In order to reduce the heat dissipation from the pipeline to the soil, a thermal insulation composite layer is added on the outside of the pipeline for medium and small-diameter heat transfer crude oil or heating pipelines.Common insulation material is rigid polyurethane foam plastic, the applicable temperature is -185 ~ 120℃.To increase the strength of the soft material, a layer of high-density polyethylene is placed over the insulation to form a composite structure to prevent groundwater from seeping into the insulation.

The outer surface of the steel tube was shot blasting and derusting treatment and corona treatment of the outer tube surface were carried out with the high pressure polyurethane foaming equipment to improve the bonding performance of the heat preservation tube.The insulation layer is made of rigid polyurethane foam with a density of 60kg/m3 to 80kg/m3, which fully fills the gap between the steel tube and the casing and has a certain bonding strength, so that a solid whole is formed among the steel tube, the outer casing and the insulation layer.Polyurethane foam has good mechanical properties and thermal insulation properties, usually can withstand temperature of 120℃, through modification or combination with other thermal insulation materials can withstand temperature of 180℃.