1. Structural Form
Pipe fittings: Steel pipe fittings, PERT pipe fittings, PE pipe fittings, etc.
Insulation Material: Hard polyurethane foam plastic; Leak Alarm Line: During the manufacturing of high-temperature pre-fabricated buried insulation pipes, an alarm line is embedded in the insulation layer close to the steel pipe. In the event of a leak in any part of the pipeline, the alarm line transmits the signal, triggering an alarm on a dedicated detection instrument, which displays the exact location and extent of the leakage. This enables quick notification to maintenance personnel to address the leaking section and ensure the safe operation of the heating network.
Outer sheath: Made of high-density polyethylene outer sheath, glass fiber outer sheath, galvanized iron sheet, etc.

2. Applicable Range
Polyurethane pre-insulated buried pipe fittings are suitable for heating and cooling of liquids and gases at temperatures not exceeding 150°C and pressures not exceeding 2.5Mpa. Steel sleeve steel pre-insulated buried pipe fittings are suitable for heating and cooling of liquids and gases at temperatures not exceeding 350°C and pressures not exceeding 2.5Mpa.

3. Standard of Execution
High-Density Polyethylene (HDPE) Outer Sheath Polyurethane Foam Pre-fabricated Direct Burial Insulation Pipe (GB/T 29047-2012)
High-Density Polyethylene Outer Sheath Polyurethane Foam Pre-Fabricated Direct Burial Insulation Pipe (CJ/T 114-2000)
Integrally Pre-insulated Pipe System for Underground Geothermal Networks – Insulating Pipes Comprising a Working Steel Pipe, Polyurethane Insulation, and Polyethylene Sheath (EN253-2003).
"Technical Conditions for Pre-fabricated Direct Burial Steam Insulation Pipes for Urban Heating (CJ/T200-2004)"
"Technical Code for Pre-fabricated Direct Burial Steam Pipeline for Urban Heating (CJJ104-2005)"

4. Service Life
The product can be continuously used for 30 years under normal operating conditions.