What is the minimum bending radius when bending and laying PE pipes?

PE pipe is widely used in water supply and drainage, gas transportation and other fields because of its excellent flexibility and corrosion resistance. In the actual laying process, due to the complex terrain or design requirements, it is often necessary to bend the PE pipe. At this time, it is very important to master the minimum bending radius of the PE pipe, which is directly related to the safety, service life and construction efficiency of the pipeline system.

The so-called minimum bending radius refers to the minimum inner radius of the bending arc of the PE pipe in the bending state. If the bending radius is too small, it will lead to excessive stress inside the pipe, which may cause the pipe wall to stretch and thin, crack, and even affect the pressure bearing capacity and structural integrity of the pipeline. On the contrary, too large bending radius may increase the construction difficulty and cost, and cannot adapt to the complex construction environment. The minimum bending radius of

PE pipe is not a fixed value, it mainly depends on the nominal outer diameter (DN) of the pipe and the specification series of the pipe (such as SDR value, that is, the standard size ratio, which is the ratio of the nominal outer diameter to the nominal wall thickness). Generally speaking, the larger the outer diameter of the pipe, the larger the minimum bending radius; the larger the SDR value (that is, the thinner the pipe wall), the more stringent the requirements for the bending radius.

In industry standards and practical engineering applications, a reference range is usually given. For example, for the PE water supply pipe of SDR11 series, at room temperature (about 20 ° C), the minimum bending radius is about 12.5 times the nominal outer diameter of the pipe; for the PE water supply pipe of SDR17.6 series, the minimum bending radius is about 25 times the nominal outer diameter of the pipe. Special attention should be paid to the fact that this is only a general reference value. The specific value should be subject to the product manual or relevant design specifications provided by the pipe manufacturer. There may be differences in the minimum bending radius of pipes from different manufacturers and different grades (such as PE80, PE100).

In actual construction, in order to ensure that the bending laying of PE pipes meets the requirements, the following points should be paid attention to: First, before bending, the product parameters of the pipe should be carefully checked to clarify its minimum bending radius. Secondly, the bending operation should be carried out slowly and evenly, and the use of violent force bending should be avoided to prevent pipe damage. For larger diameter PE pipes, special pipe bending tools or preheating (temperature and time need to be controlled to avoid overheating damage to the pipe) can be used to assist bending, but the degree of bending needs to be strictly controlled. In addition, the bent pipe should be fixed to prevent rebound and ensure that its bending radius in the working state is not less than the specified value.

If the terrain conditions of the construction site cannot meet the minimum bending radius requirements of the PE pipe, it should be considered to change the pipeline direction by connecting pipe fittings, such as using elbows. It is strictly forbidden to bend the PE pipe to less than its minimum allowable bending radius in order to accommodate the terrain, so as not to leave safety hazards.

In short, accurately grasp the minimum bending radius of the PE pipe when bending and laying, is an important link to ensure the quality of PE pipeline engineering. Construction personnel should fully understand the relevant standards, combined with specific product characteristics and site conditions, scientific construction, to ensure the safe and stable operation of the pipeline system.