ContiTech belts replace gearbox in Chinese wind turbines

HANOVER, Germany—Continental A.G.'s belting technology is helping Xinjiang Goldwind Science and Technology catch the wind.

Engineers with ContiTech, a division of Continental, combined the two timing belt technologies to develop a new belting product that allows for the rotor blades of wind turbines to be adjusted without the use of gears or hydraulics. The belts are being made at Continental's site in Dannenberg, Germany, where the company recently invested $2.5 million to help meet Goldwind's demand for 62 miles of belting each year.

The belts are based on Synchrodrive technology. To achieve a connection with the turbine's tension member, galvanized steel cords are integrated into the belt's interior and coated with polyurethane, which furnishes both the teeth and the back of the belt. Polyurethane is particularly abrasion-resistant.

Most notably, Continental said in its release, is the fabric used in the belt production.

"The fabric reduces wear and absorbs noise and also provides a much more stable structure for the timing belt. This enables us to significantly improve the belt's performance yet further," Rolf Marwede, head of Continental's Dannenberg location said in a statement. "The fabric reinforces the teeth and improves run-in behavior, which in turn, boosts efficiency. Ultimately, we have brought together two product groups to develop the ideal solution for Goldwind's application."

The belting materials are resistant to temperatures ranging between -55°C and +80°C as well as to oils, greases and fuel, according to the Continental

The company also said its belts do not need oil or lubrication, which offers an advantage for turbines that located offshore and may be difficult to maintain. This makes them especially suited in use on wind turbines located offshore, and Goldwind is one of the few companies to market turbines that use drive belts instead of gearboxes.

"There are some advantages to this," Marwede said. "For instance, the system is less complex and therefore less prone to vibrations and disturbances at the top of the nacelle. Our belts are also extremely low-wear and durable."

The partnership with Goldwind is a foundational start for Continental, which said it is focused on the development of technology to support sustainability and resource conservation in areas such as wind energy.

By the end of 2019, Continental said wind turbines with a combined output of about 650 gigawatts had been installed globally. For perspective, Continental said, about 40 gigawatts would be enough to supply electricity to every household in Germany.

China is the leader in wind energy technology, having installed power of more than 200 gigawatts.