Quarry Southern Africa May 2019 | Page 35

BENEFICIATION CoreSlab MD Jaco de Bruin. and property-development markets. While the suspended- slab market is CoreSlab’s “bread and butter”, the company also manufactures lower volume systems for specialist markets. They include precast-concrete reservoir walls and roofs; grandstands for municipal sports and recreational centres; and structural systems. In Gauteng, there are many large manufacturers and a number of start-up precast companies, and the market has also felt the impacts of a decline in spending on infrastructure at national, provincial, and municipal levels. In Limpopo, CoreSlab has also felt the impacts of decline in both the civil engineering and property-development markets. However, the decision to specialise has helped the company in these very challenging conditions. Meanwhile, the bridge beam market is also fiercely competitive. There are three suppliers in the northern area, namely the Free State, Gauteng, Limpopo and the North West, as well as a number of manufacturers in KwaZulu-Natal and the Western Cape. However, the barriers to entry are high due to the cost of establishing the manufacturing plant and moulds. CoreSlab has a full engineering workshop that makes its own moulds. Challenges The biggest benefit of precast slabs is that whatever can go wrong goes wrong in the factory rather than on site, and there what is likely to go wrong is typically with concrete compaction. De Bruin describes another daily challenge of precast as the quality of the rebar. “The rebar has to be of the same quality as the concrete and so a consistent supplier is essential. Your rebar needs to fit, and the challenge is that much rebar is made by a manual process, which introduces the element of human error. In addition to quality of supply, we have a full-time fixing team on site. With precision manufacturing such as precast, even a two-degree error makes a difference in a mould. It’s never a question of rejecting it, however, but fixing it — which affects efficiency.” Weather is a challenge due to the factory being open to the elements, though the time can be made up by either working Saturdays or by steam-cure of the concrete whereby the concrete cures faster.  www.quarryonline.co.za  QUARRY SA | MAY/JUNE 2019_33