Nizhny Novgorod Aircraft Manufacturing Plant Sokol produces steel and aluminum foundry products both for its own needs and for supplies to other aircraft manufacturing enterprises. Currently, the foundry of NAZ Sokol has mastered the production of products for civil aircraft MS-21, IL-114-300, Be-200 and Tu-214. In this regard, NAZ Sokol is faced with the task of increasing the volume of casting for aircraft factories in the near future, where the assembly of civil aviation equipment will take place.
The quality of the future casting depends on many factors: the correctness of the development of design documentation, the quality of the charge material, compliance with the operating modes of the equipment, compliance with the requirements of the technological process. That is why the quality control of manufactured products begins with the input control of the initial charge materials, the molding mixture, checking the geometric dimensions of the tooling and continuous monitoring of the operating modes of the equipment.
The processes of steel and aluminum casting are among the most complex, expensive and energy–consuming production processes associated with a large amount of pre-production work. In order to obtain high-quality products, it is necessary to carry out continuous control of production at all its stages. For example, in the manufacture of aluminum casting, the parameters of the molding and core mixture, its physico-mechanical properties, gas permeability, the absence of impurities and scale in them, the calcination temperature and the holding time are controlled. During the melting process, gas saturation samples are monitored, and when casting parts, samples are cast separately to control the chemical composition, mechanical tests, and metallographic analysis, which are performed for each melting. Then the castings are heat treated, during which the time and temperature of the castings in the furnace are continuously monitored. After heat treatment, the castings are sent for luminescence control, which allows to identify surface defects, and radiographic control, which allows to identify internal defects in the castings.
 |
| Quality control of casting at the aircraft factory. |
| Source: uacrussia.ru |
Next, the master of the production site visually and with the help of measuring tools checks the geometric dimensions of the parts, fills out the necessary documents and presents the products to the Bureau of Technical Control (BTK) for acceptance. The BTK controller verifies the correctness of the documentation, verifies that the part meets the requirements of the design and technological documentation and makes a mark on the shelf life of the product. Only after that, the batch of finished products from the foundry is sent further along the production chain, or shipped to the customer.
Classical casting technologies are gradually being complemented by new additive technologies. In the near future, it is planned to purchase 3D printers for printing molds with sand and plastic. The drawings of the parts are complemented by 3D models that allow you to quickly create the necessary equipment. And the use of digital control and measuring machines makes it possible to obtain a complete comparison of the geometric parameters of the resulting casting of its 3D model, thereby ensuring control of the entire surface of the product.
