How to divide HDPE double-wall corrugated pipe into S1 and S2

In the selection of HDPE double-wall corrugated pipes, the terms S1 and S2 are often encountered. For many users, how to accurately distinguish them is the key to ensure the quality and applicability of the project. As a professional pipe manufacturer, AD Pipeline will explain the difference and identification method of HDPE double-wall corrugated pipes S1 and S2 in detail for you.

First of all, we need to make it clear that S1 and S2 are the common names for two different ring stiffness grades of HDPE double-wall corrugated pipes. Ring stiffness is an important indicator to measure the ability of pipes to resist external pressure, and is directly related to the buried performance of pipelines. In simple terms, the ring stiffness grade corresponding to S1 is usually SN4, that is, it can withstand the pressure of 4 kN per square meter; while the ring stiffness grade corresponding to S2 is SN8, that is, it can withstand the pressure of 8 kN per square meter. This is the core difference between the two.

So, in practical applications, how to distinguish between S1 (SN4) and S2 (SN8)? The most direct way is to check the product logo. HDPE double-wall corrugated pipes produced by regular manufacturers, such as those produced by AD pipes, will be clearly marked on the outer wall of the pipe with information such as product model, specification, ring stiffness grade (such as SN4 or SN8). When purchasing, users only need to carefully check the code or label on the surface of the pipe to clearly distinguish whether it is S1 or S2 level.

Secondly, from the perspective of performance and application scenarios, the S1 (SN4) grade HDPE double-wall corrugated pipe, due to its relatively low ring stiffness, is usually suitable for some occasions where the pipe ring stiffness is not high, such as ordinary municipal drainage, building community drainage, farmland irrigation, etc. In these scenarios, the external pressure on the pipe is relatively small. The S2 (SN8) grade HDPE double-wall corrugated pipe has higher ring stiffness and can withstand greater external pressure, so it is more suitable for projects with large burial depth, high soil pressure, and may withstand vehicle loads or special load-bearing requirements, such as main road drainage, drainage in heavy vehicle traffic areas, and industrial wastewater discharge, which require more stringent pipeline strength and stability.

In addition, in terms of the structure and weight of the pipe, the S2 (SN8) pipe of the same specification usually has a thicker wall or a more optimized crests and troughs structure design than the S1 (SN4) pipe to ensure its higher ring stiffness. Therefore, under the same pipe diameter, the weight of the S2 pipe will also be slightly heavier than that of the S1 pipe. However, this needs to be comprehensively judged in combination with the production process and product design of the specific manufacturer, and cannot be used as the only basis for discrimination. The most reliable thing is to check the product logo.

In summary, to distinguish the S1 and S2 of HDPE double-wall corrugated pipes, the most fundamental thing is to look at their ring stiffness grades (SN4 corresponds to S1, SN8 corresponds to S2), and confirm through the product logo. Understanding their differences, users can choose the appropriate grade of HDPE double-wall corrugated pipe according to specific engineering design requirements, buried depth conditions, external loads and other factors to ensure the safety, stability and cost-effectiveness of the project. When purchasing, it is recommended to choose a strong and reputable brand like AD Pipeline to ensure that the quality and performance of the product meet the relevant standards.