PU direct-buried insulated pipe is formed by tightly combining the carrier pipe that conveys the medium, a rigid PU foam insulation layer, and an HDPE outer jacket, with supports and alarm devices in the insulation layer. A prominent advantage of PU direct-buried insulated pipe over other insulation materials is its good thermal insulation: heat loss is only 25% of that of conventional pipe, so long-term operation can save a large amount of energy and significantly reduce energy costs.

　　PU direct-buried insulated pipe has strong waterproofing and corrosion resistance, requires no additional trench, and can be buried directly underground or in water. Construction is simple and fast, and overall cost is low.

　　PU direct-buried insulated pipe has a service life of 30–50 years; correct installation and use keep network maintenance costs extremely low. It also offers good corrosion and impact resistance at low temperatures and can be buried directly in permafrost.

　　Today, black-jacketed direct-buried LSAW pipe introduces two direct-burial methods for PU direct-buried insulated pipe: one-time compensation direct burial and no-compensation direct burial.

　　1. Uncompensated direct-buried laying method for PU direct-buried insulated pipe: Uncompensated direct-buried laying of PU direct-buried insulated pipe uses the frictional resistance between the soil and the outer jacket to fix the pipeline. Compensators, fixed supports, pipe fittings, sliding supports, etc. need not be installed on the pipeline.

　　2. One-time compensation direct-buried laying method for PU direct-buried insulated pipe: This method uses a compensator to offset part of the total deformation generated by the pipeline under the design temperature difference, so that compressive and tensile stresses are essentially balanced, thereby reducing tensile or compressive deformation stress in the pipeline. One-time compensators are suitable for pipelines with operating temperature ≤120°C and operating pressure ≤1.6 MPa, and have a service life of more than 30 years.

　　That concludes the above introduction to methods relating to black-jacketed direct-buried LSAW pipe and PU direct-buried insulated pipe. We hope it is helpful. Follow us for more industry news. https://www.sdhpgy.com