Mammoet has announced its Wind Turbine Assembly (WTA) lifting system is now ‘design ready’ and plans for it to be ready for market by early 2023.
First announced in 2017, the electric-powered WTA system has been developed as an alternative to conventional All Terrain and crawler cranes for wind turbine erection. The WTA attaches directly to a series of anchor points located at the top and bottom of a tower section using a number of clamps. Once installed it can then push itself up to the next tower section before re-attaching itself. Using the tower for support, the system can handle tower sections, blades and nacelles up to 150 tonnes – and in theory, lift them to infinite hub heights.
The company says it offers significant benefits over traditional cranes, including when it comes to transport and installation. It only requires nine trailers to be transported to the site, and only five to move between turbines, which the company claims offers 50 per cent improved relocation times.
It also weighs less and offers more a compact footprint compared with traditional cranes, resulting in the need for smaller pads and lessened ground pressures concerns. Another advantage is that it does not require additional space for installing large booms, that can measure up to 200 metres. In addition, can also operate in wind speeds up to 20m/s.
The company said: “As turbines grow, more prime movers and trailers would be needed to get crane components to site; plus, a larger surface area would need to be prepared to create suitable hardstands at each turbine location for the crane to be erected and operate on. These factors would add significant time and cost to projects.
“The answer was to reconsider how cranes supported themselves. The majority of crane components that need to be moved, mobilized and demobilized between turbines are there only to support the lifting work. They take time and money to handle and increase the weight placed on the ground by lifting equipment and therefore the hardstand required, but do not perform assembly themselves. What if they could somehow be replaced? This thinking led us to develop the Wind Turbine Assembly crane (WTA).”