The implementation standard system of polyurethane insulation pipes is based on Chinese national standards, supplemented by industry norms and international technical references, forming a multi-level and full chain technical constraint framework to ensure the compliance and reliability of products in all aspects of design, manufacturing, construction, and acceptance.

The national mandatory standard is the cornerstone of the system. The current effective and most authoritative one is GB/T 29047-2021 High Density Polyethylene External Protection Pipe Rigid Polyurethane Foam Prefabricated Directly Buried Thermal Insulation Pipe and Pipe Fittings. This standard was released in 2021 and fully replaced the 2012 version. It provides unified and mandatory requirements for the material properties, structural dimensions, physical indicators (such as thermal conductivity, closed cell rate, compressive strength), and inspection methods of working steel pipes, insulation layers, and outer protective pipes. It is the minimum technical threshold that all production enterprises must meet. Its technical indicators are directly related to engineering safety and energy efficiency, and are the legal basis for engineering acceptance and quality supervision.

As an extension of the national system, industry-specific standards support specific application scenarios. GB/T 38097-2021 Glass Fiber Reinforced Plastic Outer Sheath for Urban Heating Polyurethane Foam Prefabricated Directly Buried Thermal Insulation Pipes and Pipe Fittings specifically specifies the products using glass fiber reinforced plastic as the outer sheath, and defines its key parameters such as resin content, Babbitt hardness, corrosion resistance, etc., which is suitable for high corrosion or overhead laying environments. GB/T 37263-2018 "High density polyethylene outer protective pipe polyurethane foam prefabricated buried insulation steel plastic composite pipe and fittings" fills the technical gap of metal plastic composite fittings for steel plastic composite structures. It is worth noting that the original industry standard CJ/T 114-2000 has been replaced by the GB/T 29047 series standards due to technological iteration and is no longer used as the current effective basis.

Although international standards are not mandatory, they are widely cited as technical references. EN 14315-2:2013 Thermal insulation materials for buildings - Rigid polyurethane foam materials - Part 2: Performance requirements is a mainstream European standard, and its test methods for thermal conductivity, dimensional stability, water absorption and other aspects of polyurethane foam have been adopted by Chinese testing institutions as a supplementary basis for type inspection. Although ASTM C-591 is a standard for polyisocyanurate (PIR) materials, different from polyurethane (PUR) systems, it is used as a performance comparison reference by engineering parties under some high-temperature conditions. At present, there is no ISO standard specifically for the overall system of polyurethane insulation pipes, but relevant material standards (such as ISO 22391 for PE-RT pipes) indirectly affect the development of supporting standards in China.

The material basic standard is the underlying support of the implementation system. Although it is not directly named as the "insulation pipe standard", it is explicitly referenced by core standards such as GB/T 29047-2021. GB/T 13663 "Polyethylene (PE) Pipes for Water Supply" specifies the physical properties such as density, tensile strength, and elongation at break of HDPE outer protective pipes; GB/T 3091 "Welded Steel Pipes for Low Pressure Fluid Transport" and GB/T 9711.1 "Technical Conditions for Delivery of Steel Pipes for Petroleum and Natural Gas Industry Transport" regulate the material and manufacturing requirements of working steel pipes. These material standards ensure that the source quality of each component of the insulation pipe is controllable.

In terms of local and group standards, there are currently no special local standards for polyurethane insulation pipes in Shandong Province and Linyi City, and the technical requirements are uniformly implemented in accordance with national standards. The China Urban Water Supply and Drainage Association and other organizations have not yet released T/standards, and the technological evolution of the industry is still dominated by national and industry standards. The current system has formed a complete closed loop of "national mandatory standards as the backbone, industry specific standards as the supplement, international standards as the mirror, and material standards as the basis", supporting the long-term stable operation of heating pipelines in cold regions such as Linyi, Shandong.