Hidden troubles of wind turbine quality 2

Problem l. Production capacity surplus shall inevitably lead to the price war of wind turbine set similar to that of color TV and refrigerator, therefore, resulting in the price and profit decline of wind power manufacturing products. Take tower flange for an example, the average profit margin of products is currently just about 5%. For some excellent enterprises, they can also achieve the development of enterprises with certain production scale and reJatively high market share through technoIogy innovation and favorable cost control abilityI however, for the small scale enterprises got involved late without independent research and development capabilities, they can only earn profits reIying on loosing quality control and process management, and adulteration. Such as raw material control, tower flange is the important Supporting and connecting component for wind power generator set. It suffers from the effects of bitter cold or torrid heat and extreme temperature difference as weIl as the impact of complicated wind alternating load, therefore, it must seIect steel ingot or continuous casting round billet after refining and vacuum degassing but not continuous casting sIab for raw materials since defects of continuous casting slab are normally at the middle Iayer of the thickness direction and hard to remove after forgjng and heat treatment. AIthough using continuous casting slab reduces the costs, it buries hidden troubles of quality and safety for the long-term stable operation of generator set. For another example, not strictIy perform heat treatment process and shorten heating -up and heat preservation time in order to reduce heat treatment costs, although costs falls but it makes the forged thick grain thin through heat treatment, gets small uniform pearlitic structure and e1iminates the stress, which makes it hard to meet requirements of mechanical properties, results in internal stress remaining in the tower flange constantly releasing over time, makes the deformatIon of fIange, may leads to local concave or convex of tower and brings risks to normal run of the generator set.