Pipe manufacturer Inkulu Plastic Pipes has added a new high-density polyethylene (HDPE) structured wall pipe product range to its offering.

Inkulu Plastic Pipes sales and marketing manager Faize Gafoor tells Engineering News that the company can now manufacture and supply HDPE structured wall pipe which the company is branding the Gabykulu structured wall pipe – ranging from 300 mm to 1 500 mm, with a ring stiffness of 2 kN/m2 and 8 kN/m2.

This lightweight engineered pipe is useful in various gravity and non-pressure applications in the municipal, industrial, road construction, rehabilitation and marine pipeline applications.

“We introduced the new range in June last year during tough economic circumstances, but we decided to do it in expectation of an eventual increase in demand from infrastructure projects, and contractors need to be aware that we have the products they need,” Gafoor explains.

The Gabykulu product is highly abrasion resistant, tolerant of ground movement and will not corrode or deteriorate when it comes into contact with various substances.

These pipes are also characterised by their natural flexibility, which enables them to adjust to different loading conditions, vibrations, stresses and soil movements, without damage to the pipes.

Gafoor says the HDPE structured wall pipe represents the latest advancements in material and manufacturing technology, and that it is considered the frontrunner in replacing traditional pipe system materials.

For example, the HDPE structured wall pipe typically weighs less than 10% of an equivalent concrete pipe while boasting high degrees of chemical resistance to most industrial and domestic wastes. HDPE piping is also five times more abrasion resistant than concrete, and has a life span of up to 100 years.

Other benefits include the pipe’s virtually being leak proof and easy to install, with good weldability.

The Gabykulu structured wall pipes are manufactured in accordance with SANS 21138, and meet the requirements of the ISO 9001:2015 quality management system.

To join the pipes, the Inkulu low-pressure coupling –a rubber-lined steel coupling – is used. The coupling is designed to be a dedicated and simple, cost-effective method of joining large-diameter HDPE structured wall pipe for sewer applications.

New Extrusion Machine

The company also installed a new extrusion machine capable of extruding solid wall HDPE pipes of up to 1 200 mm in diameter at up to 16 bar. Inkulu Plastic Pipes is the first in the country to manufacture this diameter.

HDPE pipe has a high resistance to chemicals, abrasion and corrosion, in addition to decay-resistant properties. It has become the preferred material for the mining industry in slurry applications, as well as for clean drinking water reticulation systems.

“We noticed that consulting engineers are increasingly using 1 200-mm-diameter pipe in their designs, which is why we invested in the new extrusion machine,” Gafoor explains, adding that continuous development in infrastructure across Africa justifies the decision. “About 40% of Inkulu Plastic Pipes’ business derives from Africa.

He claims that this makes the company the only local manufacturer capable of extruding HDPE solid wall pipes of that size. Previously, pipes of that size had to be imported from Europe.

“To have this size available means that bulk water lines, for example, can be constructed in a larger size, which is the kind of thing needed to advance South African infrastructure,” Gafoor says.

Although projects in which the new machine would be used were sparse after the outbreak of Covid-19, Inkulu Plastic Pipes upgraded the machine to extrude pipes as small as 400 mm in diameter. When originally bought, the machine could reach a minimum size of only 630 mm.

“We have had continuous work for the smaller sizes, from 400 mm to about 710 mm,” he explains.

The machine primarily services the infrastructure market – such as bulk water main line upgrades – although Gafoor says the company has enjoyed significant interest from the mining and agriculture sectors.