Plumbing Africa February 2019 | Page 52

50 FEATURES Geberit’s revolutionary high-rise drainage system From 20 to 22 November last year, industry professionals, the media, and executives were invited to the launch of Geberit’s groundbreaking new SuperTube system. It does this by directing the water into a swirl action around the outside of the pipe as it flows, creating a central column of air inside the drainage pipe, which serves the same function as the old ventilation pipe. In South Africa, the system has already found a home in the Acsiopolis development in Sandton, Johannesburg. By Warren Robertson The Geberit SuperTube is a revolutionary new system, designed to optimise the drainage in high-rise buildings. Effective drainage is about speed and maximising the volume of water that can be discharged from the building at any given time — this is especially important in high-rise buildings where numerous sources of drainage entering the same system means that large volumes of soiled water need to be drained efficiently. Failure to do so will result in poor drainage performance and can result in over/under pressures on the system. Traditional systems rely on a separate ventilation pipe to be laid alongside the drainage pipe to introduce air (parallel vented system) and to release pressure build-up that can slow down the rate at which water flows out of the building. With water falling directly downward, the air in the drainage system can cause dangerous over pressures, slowing down the rate at which the water flows. The new Geberit SuperTube system addresses these flow errors while eradicating the need for a separate ventilation pipe entirely, thereby saving a vast amount of space, time, and material costs in the construction of high-rise buildings. February 2019 Volume 24 I Number 12 Geberit explains that the SuperTube system allows for pipelines with consistently smaller dimensions of d110mm, which in turn means that smaller pipe ducts can be used. An additional benefit is that horizontal pipelines can be laid to a length of up to six metres without a slope to save even more space. In the SuperTube system, the outflowing water is set in rotation in the Geberit HDPE Sovent fitting, which is designed to guide the water into the stack and force it into the twisting spiral that is its hallmark. With the water twisting against the sides of the pipe, the resulting annular flow creates a stable, continuous column of air on the inside, allowing rapid discharge of water. As the water rushes downward, it is inevitable that it would meet with a change in direction or a position where it needs to flow parallel with the ground. Due to various forces, maintaining the column of air inside the annular flow is impossible and so the Geberit HDPE BottomTurn bend allows the wall of water to break using a flow divider and the annular flow to become a layered flow without disrupting the column of air. This change significantly reduces impulse losses or gains compared with conventional solutions. Changing direction back to the vertical also needs a unique solution to transform the layered flow into an annular one once again. This is done through the unique Geberit HDPE BackFlip bend, which causes the layered flow of water to swirl, allowing it to rotate through the vertical pipeline and keep the column of air intact. According to Geberit, with the Geberit SuperTube, the discharge capacity is 12ℓ/s. www.plumbingafrica.co.za