Massive mould for wind turbine blades

ONE of the largest moulds for composite production ever used in South Africa has been installed at Isivunguvungu Wind Energy Converter in Cape Town.

With its two halves weighing a whopping 44 tons, the mould is to be used for the production of 50m wind turbine blades.   Each blade will weigh approximately 12 tons, with the glass fibre reinforcement and resin each constituting about half that.

The mould was built in China for Gurit of Switzerland, a leading global supplier of advanced composite materials for the wind energy market.    Gurit supplies both infusion and prepreg blade technology as well as all the relevant materials needed for building composite blades.

Isivunguvungu (Zulu for ‘big storm’) Wind Energy is the brainchild of Dr Michael Kast, whose was previously involved in composite boat manufacture (he designed the yacht ‘Broomstick’ which won the Cape-to-Rio race in 1993).   Kast has been engaged in the wind energy sector for the past 10 years and managed to assemble the group behind the Isivunguvungu venture, which plans to manufacture about three of the blades a week.    About 125 layers of glassfibre are used for each half of the blade and laid up in the mould, with the resin then added by vacuum infusion.

The halves are then joined with an adhesive supplied via a Dopag dispensing system.

Daunting specs are the order of the day here: at maximum rpm, the tip of the blade will revolve at around 300kph.   At optimum performance, each turbine will generate about 2.5 megawatts of power a day.

Isivunguvungu operates from a large warehouse in the Cape Town harbour, where it will be supplying the wind energy market from.  

www.i-wec.co.za

www.gurit.com