The ring stiffness of
HDPE double-wall corrugated pipe is the core indicator to measure its compressive performance. It is usually expressed in SN (Stiffness Number) and the unit is kN/m ². Common grades include SN4, SN8, SN12.5, SN16, etc. The larger the value, the stronger the compressive ability of the pipe. 1. Ring stiffness grade and meaning SN4: It can withstand a pressure of 4 kN per square meter and is suitable for light-load environments such as sidewalks and green belts. SN8: It can withstand a pressure of 8 kN per square meter and is suitable for non-motor vehicle lanes and small vehicle traffic areas. SN12.5/SN16: It can withstand a pressure of 12.5 kN or 16 kN per square meter and is suitable for heavy-duty vehicle roads, municipal trunk roads and other heavy-duty scenarios. 2. How to choose the appropriate ring stiffness? Buried depth: Shallow burial (2 meters): SN4 or SN8 is optional. Deep burial (3 meters): SN12.5 or higher grade needs to be selected. External load: Frequent areas of vehicle rolling: SN8 and above are preferred. No external load: SN4 can meet the demand. Soil conditions: Soft soil: Higher ring stiffness is required to prevent pipe deformation. Solid soil: The grade can be appropriately reduced. 3. The practical significance of ring stiffness Ring stiffness directly affects the service life and safety of pipes. For example:
In municipal drainage projects, SN8 pipes can withstand the pressure of conventional construction machinery; in farmland irrigation, SN4 pipes are sufficient to cope with soil side pressure. 4. Precautions National Standard: Domestic HDPE double-wall corrugated pipe implements GB/T 19472.1-2019 standard. When purchasing, you need to confirm that the product meets the corresponding ring stiffness grade. Construction Specifications: Backfill soil needs to be layered and tamped to avoid local stress concentration; pipeline foundation should be flat to reduce the risk of uneven settlement.
If you need professional selection suggestions or high-quality HDPE double-wall corrugated pipe (such as AD HDPE double-wall corrugated pipe series), please contact Hubei AD Building Materials Co., Ltd.: 173-9998-9993 to get customized solutions.