The corrugated sewer system pipe can be installed in various applications, each with its own requirements. Over the years, pipe manufacturers have developed variations on the classic pipe to enable the product to adapt to various installations.
GROUND WITH OCCASIONAL PRESENCE OF WATER
In some cases, corrugated pipes have to be laid in soils where there is occasionally groundwater, the level of which fluctuates throughout the year. If the pipe has not been laid properly, such water can seep from outside into the pipe.
To overcome this problem, a hydro-expanding gasket was devised, which increases in volume when it comes into contact with liquids and occupies the entire space between the pipe corrugations and the inner wall of the coupler. It is not a replacement for the normal jointing system but should be added to the standard gaskets supplied with the pipe. The hydro-expanding gasket should be placed in the groove between the second and third rib of the pipe to stop seepage or leakage at the points where the pipes are connected.
The hydro-expanding gasket supplied by Polieco is called No Loss: it is a synthetic rubber joint with added polymers.
STEEP SLOPING TERRAIN
Italy is characterised by the presence of mountains and hills. There are many steep sloping areas where it is necessary to install a drainage system. In this type of installation, the effluent inside the pipes can reach high velocities, which can obviously increase the abrasion phenomenon in the pipeline as well as create overpressure in the end downstream manhole.
In order to facilitate the installation of corrugated pipes also in mountainous areas, a double-wall corrugated pipe was designed where the inner wall is also corrugated. The internal corrugation, in fact, allows for the slowing of the flow of water inside it, greatly reducing the risks described above.
The ideal pipe for this type of application presented by Polieco is the Slow Motion corrugated pipe, part of the Ecopal sewer system range.
CLEAR SPACE
Italian legislation identifies clear spaces, i.e. those areas where there are aquifers or areas around aqueduct wells that could be contaminated if polluting effluents were to spill into the subsoil. In these areas, one must foresee the possibility of a spill and ensure that it does not pollute the soil.
Thus, double-pipe systems were developed. The system consists of the installation of two concentric pipes separated by transverse collars or spacer strips placed on the outer wall of the inner pipe. A double gasket is inserted on the inner pipe to provide a greater watertight seal. In the event of leaks or ruptures, this system prevents soil pollution as waste water remains trapped between the two pipes.