A comprehensive range of Durodrain unplasticised polyvinyl chloride (uPVC) pipes valued at R4.4-million has been supplied by water reticulation, drainage pipe and fitting systems manufacturer DPI Plastics to the City of Matlosana, in the North West, for its R16-million sewerage upgrade project.

DPI Plastics was commissioned by the appointed contractor to supply more than 4.3 km of 560-mm-, 500-mm-, 400-mm- and 160-mm-diameter pipes to the upgrade project, located in the town of Jouberton.

DPI Plastics product manager Renier Snyman notes that the order for the 560 mm Durodrain pipes is, to date, the largest-diameter locally manufactured sewerage pipe supplied to a project.

“The larger bore ensures that greater volumes of sewage are conveyed in gravity sewers. “This improves efficiency, compared with 500 mm sewer pipes, which were, until recently, the largest size locally available.

“I am confident that demand for larger-bore sewerage pipes will continue, as they provide an excellent balance in terms of durability, efficiency and affordability,” he explains.

The pipeline was upgraded and expanded owing to an increase in population in the area. Varying diameters were required to meet flow-rate requirements.

The supply project began in April 2014 and was completed four months later, in line with specified budgets and deadlines.

The pipes were delivered in 6 m lengths in varying arrangements: 328 lengths of 560 mm pipe; 166 lengths of 500 mm pipe; 176 lengths of 400 mm pipe; and 58 lengths of 160 mm pipe.

DPI Plastics is also the only local manufac-turer able to produce 630 mm uPVC sewer pipes, owing to its Krauss Maffei extrusion line, which can produce up to 22 t/d of South African National Standards-approved polyvinyl chloride (PVC) piping products.

Snyman says PVC is a more cost-effective material, with a longer life expectancy, compared with industry-standard steel, concrete and high-density polyethylene, which are often prone to corrosion damage caused by methane and chemicals over time.

“PVC boasts a smooth inside wall, which results in a low-friction coefficient, thereby ensuring resistance to algae growth, which is a common cause of blockage in sewerage systems,” he says, adding that integral joints with rubber seals result in effective sealing and resist root ingress.

Another major advantage of the Durodrain range is that it employs best-practice PVC methods, as the pipes are manufactured in ISO 9001-accredited factories that reduce wastage by recycling materials. These accredited factories also ensure the responsible use of additives and stabilisers and a reduced carbon footprint, compared with alternative materials and manufacturers.

Snyman adds that PVC is considerably lighter than steel or concrete. “This means that pipes can be transported more efficiently by truck, which reduces fuel consumption and improves turnaround times. The lightweight characteristics of the pipes also ensure that on-site installation times are dramatically improved,” he concludes.