HDPE( High Density Polyethylene) DWC Pipe is the new technology of pipe conveyance for sewer and drainage. The pipes are corrugated on the outer wall to increase stiffness and smooth in the inside wall for a better flow. The pipes were introduced in the East African market as a replacement for precast concrete pipes which have been used before. The pipes are a modern product of waste water and Drainage management in an eco-system that is evolving and ever-demanding due to extreme weather patterns and population pressure. DWC Pipes are manufactured from Polyethylene material which is the most stable plastic hence does not react with toxic and chemical wastes flowing in sewer as compared to other plastics. Double Wall Corrugated pipes are corrosion resistant, acids, bases and salts as compared to concrete.
The pipes are produced at a standard length of six meters (6m) compared to concrete pipes that have traditionally been casted at a maximum length of 1.2meters. This therefore means that jointing work is greatly reduced within a specified span and conversely reducing the probability of leakages within the same. The DWC pipes are lightweight compared to concrete thus reducing the amount of machinery used on site, transportation costs, easier installation thus saving in the construction time and timely delivery for projects.
More importantly, the pipes have excellent flow characteristics because they are smoother than concrete meaning that there is less drag and low tendency of turbulence at high flow. The non-stick surface almost eliminates scaling and pitting thus rendering the pipe to longer service life. HDPE generally has a lifespan of up to 50years as compared to concrete pipes which last up to 20years.
HDPE DWC pipes are majorly used in buried drainage, sewerage discharge, communication cable casing, farmland water conservancy (Canals) and other non-pressurized waste water applications. These pipes have been adopted by various agencies in the ministry of water and sanitation to address the problems of inadequate sewer infrastructure in urban areas as well as expansion into the metropolitan settlements outside the urban areas. The outcome has been positive because there is a growing access to sanitation services and more effective drainage systems than before.
In first world nations infra-red cameras are installed inside the DWC pipes to capture flow rate and volume of waste water being channeled out of municipalities. With such information, planning and improvements of waste water management in urban areas is easier since it is data driven. It is also important to note that in the case of communication cable casing, once the pipes have been installed and cables running on the inside; whenever there is an upgrade in the communication systems, old cables are retracted while new ones are placed without unearthing of road paths, cabros on walkways and road-crossings thus saving on restoration costs and preservation of existing infrastructure and less disruption to the environment.
HDPE DWC Pipes is therefore the future of safe, affordable and sustainable provision of waste water and sanitation services as anchored in Vision 2030. These pipes are manufactured by Kirin Pipes Co Limited located off Ngong road at Embulbul.
Story by Chris Mwangi, Technical Sales Manager, Kirin Pipes Co Limited.