With a length of 100 meters and an accuracy of 10 mm, how are the “big windmill” blades made?

As the temperature gradually drops, various regions enter the peak of electricity consumption throughout the year. According to data from the National Energy Administration, at present, my country's installed capacity of renewable energy has exceeded 50% of the total installed capacity, and the installed capacity scale continues to achieve new breakthroughs.
The reporter recently learned from Gansu Province that Gansu Province's proportion of new energy installed capacity and power generation are both second in the country. The power supply structure is changing from "fossil energy-based to large-scale renewable energy-based" to achieve clean energy production. Among them, the northwest wind that often blows in winter plays a big role.
In Gansu, the unique geographical location allows the wind to form a "narrow channel effect" in the Hexi Corridor. The country's first 10 million kilowatt-level wind power base is located in the Hexi Corridor. There is also the country's largest onshore wind power equipment manufacturing base with the most complete industrial chain. In the cold winter, the demand for energy increases rapidly, and the green energy industry in the Hexi Corridor of Gansu is running at full capacity.
Jiuquan Economic and Technological Development Zone has an annual production capacity of 2,450 sets of wind turbine blades. In order to transport large parts such as wind turbine blades more conveniently, a new toll station has been set up on the highway. The lane closest to the side is super wide and super high, which can accommodate blades up to 150 meters long. The lane entering the toll station is also the width of three ordinary lanes, which allows the trucks pulling the blades to turn normally. The toll station is expected to open this month, and the wind turbine parts produced here are continuously arriving all over the country. In the winter Hexi Corridor, countless "white giants" stand on the vast Gobi Desert. Blades are important parts of wind turbines and can be more than 100 meters long.
CCTV reporter Jiao Jian: The main materials such as fiberglass, continuous felt, and balsa wood will be laid in different positions of the wind turbine blades with a precision of 10 mm according to the requirements of the design drawings. In the end, the root thickness of the wind turbine blade will reach 70 layers. Wind turbine blades are made of composite materials, and the weight of a blade is about 30 tons. The higher precision of the layering can not only control the weight and save costs, but also better fit the different loads required at different positions of the blades.