Subdrainage pipes, helically corrugated and perforated, are supplied in standard 6 m. length sections ( 4 m. or 9 m. lengths can be order). The diameter goes from 15 cm. to 80 cm. .
CHANEL-DUCTS
The circular chanel-ducts are used for the collection and drainage of the surface waters, particularly for slopes and road embankments. They are obtained by assembling plates.
