
Denver Colorado headquartered Keystone Tower Systems and GE Renewable Energy have announced a major milestone in the development of tapered spiral welding with the installation of the first commercial spiral-welded wind tower on a 2.8 MW GE turbine. The tower was manufactured at Keystone’s factory in Panhandle in Pampa in Texas.
Keystone is now ramping up production of spiral welded towers, with additional deliveries targeted for Q1 of 2023. The first product is an 89-meter tall spiral welded tower for the GE 2.8-127 turbine, designed to be used interchangeably with GE’s conventional 89 meter tall tower. The spiral tower has received a component certification from TÜV NORD for a 40-year lifetime. Keystone and GE have also collaborated on a tower design for the GE’s 3 MW turbine platform and have signed a multi-year supply agreement for spiral towers from Keystone’s Pampa factory.
Keystone has adapted spiral welding to accommodate the tapered diameter, variable wall thickness, and high manufacturing quality required for wind turbine towers. A single machine completes the joining, rolling, fit-up, welding and severing of a tower section, resulting in continuous production of steel tower shells. Because it is a high throughput, compact system, tapered spiral welding provides economic benefits when operated in a factory setting, and can also be readily mobilized for temporary operations on-site for onshore supply or port-side for offshore supply.
Keystone’s tapered spiral welding process brings the speed, quality, and consistency of automated manufacturing to wind tower manufacturing. Keystone designs and builds its own custom spiral welding manufacturing equipment. The manufacturing process is designed to utilize coil steel, enabling a new segment of highly efficient domestic steel mills to supply into the wind industry.
Panhandle factory was built at an idled facility that formerly made drilling equipment for the oil and gas industry. When at full capacity the factory will be capable of producing approximately 1GW of towers per year. While this first factory is in a fixed location, Keystone is also developing mobile factories capable of building taller towers directly at the wind site, as detailed in the US Department of Energy’s May 2022 publication, “How Spiral Welding is Revolutionizing Wind Turbine Manufacturing.”