The main characteristics of a micro-slotted drainage pipe are that it collects excess water and evacuates it. For the first function, it is necessary that they have slots such that ground water can enter the pipe along the entire drainage line; while for evacuation, it is necessary that the pipe has a sufficient cross-section that it is free of occlusions and that it is laid with a slope such that the water can transit.
In rainwater drainage pipes, collection is ensured by the slots in the pipe itself. The slots in a micro-slotted pipe can be arranged around the entire circumference (at 360°), or only on the top (at 220°), allowing the bottom surface to collect water as it is free of slots. The width of the slots is crucial to the purpose of a drainage pipe: it must be narrow enough to prevent large particles from entering the pipe, which could result in clogging, quickly rendering the drainage function ineffective. While the slots must also need to be wide enough to allow water to flow out fairly quickly. It has been found that the ideal slot width of a drainage pipe is 2 mm.
The slots can be perpendicular to the pipe or longitudinal or diagonal to the axis of the pipe. With slotted pipes, the slotting must be in the corrugation groove so that the two peaks of the corrugation prevent the surrounding material from obstructing the slot. The combination of the thickness together with the length of the perforation allows the slotted drainage pipe to act as a filter, thereby separating the water from the suspended silt-soil.
Polieco produces different types of corrugated drainage pipe: