Is there a difference in the water pressure bearing capacity of PE pipes of different diameters?

In the application of PE pipes, many people will be concerned about a question: Is there a difference in the water pressure bearing capacity of PE pipes of different diameters? The answer is yes, but this difference is not simply determined by the size of the diameter, but by a combination of factors.

First of all, we need to clarify that the water pressure bearing capacity of PE pipes is mainly expressed by its nominal pressure (PN), which is the maximum working pressure that the pipeline can safely transport at room temperature. Generally speaking, the nominal pressure of PE pipes has multiple grades, such as PN1.0, PN1.6, PN2.0, etc. The larger the value, the stronger the pressure bearing capacity.

So, what is the relationship between the diameter and the nominal pressure? Under normal circumstances, under the same material grade and wall thickness conditions, there is no direct positive or negative correlation between the diameter of PE pipes and the water pressure bearing capacity. That is to say, it is not that the larger the diameter, the lower the pressure bearing capacity, or the smaller the diameter, the higher the pressure bearing capacity. For example, the same PE pipe of PN1.6 grade, the small diameter pipe of dn20 and the large diameter pipe of dn315, their nominal pressure is the same, and the upper limit of the water pressure that can be withstood in theory is the same.

But why do different diameter PE pipes feel different pressure bearing capacity in practical applications? This is mainly because in the design and production, different diameter PE pipes will match the corresponding wall thickness and nominal pressure according to their common application scenarios. For example, small-diameter PE pipes are often used in branch pipes with relatively high pressure requirements such as household water supply and small irrigation, and may choose higher nominal pressure specifications; while large-diameter PE pipes are more used in municipal water supply trunk pipes, sewage, etc. The design pressure will be determined comprehensively according to factors such as conveying distance and flow rate, not necessarily lower than small-diameter pipes, and may also choose different PN values due to different needs.

The key factors affecting the water pressure tolerance of PE pipes are actually the properties of the material itself (such as the strength of different grades of materials such as PE80 and PE100), the thickness of the pipe wall, and the production process. The higher the material grade, the thicker the pipe wall, the stronger the structural strength and internal pressure resistance of the pipeline, and the greater the water pressure it can withstand. Even for PE pipes of the same diameter, if the wall thickness is different, the nominal pressure will be significantly different.

Therefore, when selecting PE pipes, it is not possible to judge their water pressure bearing capacity solely based on the diameter, but should focus on the nominal pressure (PN value), material grade and wall thickness of the pipeline. PE pipe products that meet the design requirements should be selected according to the actual working pressure, medium characteristics and laying environment and other factors to ensure the safe and stable operation of the pipeline system. If there is any doubt about the specific selection, it is recommended to consult professional pipeline technicians or refer to relevant product standards and design specifications.