Construction World January 2018

The common belief that one release agent can be used for any application is far from the truth. We have release agents specifically manufactured for insitu concrete and for the precast concrete industry whether you are casting large stormwater pipes or small decorative items. When purchasing the correct release agent for your site a few things need to be considered. Firstly, is the finish to be off-shutter or will the concrete be plastered or painted. Secondly, what type of formwork will you be using: shutterply, steel forms or resin faced boards are a few of the options available. Wax based release agents, such as A.Shak’s AS7, are best for shutterply as it helps preserve the boards for future use. Superstrip is best for off-shutter applications and when using fiberglass coffers, the only release agent to use would be 3B Grease as this is a heavy-duty release agent that won’t run off the coffer before the concrete is poured. The release agent options for the precast industry are very specific to the manufacturing process of the plant. A.Shak manufactures products which are suitable for large scale operations where stripping times are critical and steam curing of the product requires that the release agent does not evaporate under high temperatures. It manufactures bond breakers for stack casting, which is normally cast on site, and where the surface finish of the product needs to be off-shutter. The decorative concrete industry in South Africa is quite diverse and the company supplies its release agents to a variety of specialists in this industry. From large to small yards all using different types of moulds in their manufacturing processes, something as small as the additives or pigments which they use, can dictate which release agent works best. Very often the small precast items are cast in natural rubber or silicone rubber moulds and to ensure longevity of these moulds, a non-solvent based product is recommended. A. SHAK prides itself on its technical back-up service which is available to advise on not only which is the correct release agent to be using but also to assist by training staff on how to apply the release agents correctly.  Concrete. A. SHAK has become the market leader and experts in this field with a technical team that can assist in recommending the correct release agent, whatever your application to ensure a quality finish to your concrete. Specialised release agents A.SHAK was established in 1958 to supply the construction industry with specialised release agents for the varied applications that are required for stripping formwork from

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CONSTRUCTION WORLD JANUARY 2018