Drilling holes is one of the most common operations in the manufacture of parts. As a result, improving the efficiency of this process is an urgent task. To improve the efficiency of the drilling process, a method was developed at the Southwestern University for drilling with pre–stressed–deformed material of the workpiece, in which the sample is subjected to elastic deformation at a load that does not exceed the proportionality limit of the workpiece material, that is, when the load is removed, the dimensions of the workpiece remain the same. As part of this work, an experimental device was developed and designed to determine the limits of elasticity and proportionality of materials for subsequent drilling of workpieces in a stress–strain state. This invention will improve the automation and accuracy of measurement. An example of measurement and calculation is considered. Calculation formulas for determining the measurement error are given.

The existing methods for detecting of casting defects and their disadvantages are considered. Hydrostatic weighing method is proposed for detecting of hidden fl aws by comparing the reference and calculated densities of the casting, method for calculating of the error is recommended. The adequacy of theoretical calculations is verifi ed experimentally

The present article describes the method and devices for material elastic limits and proportionality calculation. This invention is to allow for automation and higher measurement accuracy. Formulas for calculating measurement errors are given. An example of measuring and calculating is described.

Drilling holes is one of the most common operations in the part production. Consequently, increasing the efficiency of this process is an urgent task. To improve the efficiency of the drilling process, the South- West University developed a method of drilling for pre-stressed and prestrained workpiece material, which requires a sample to be subjected to elastic strain under load not exceeding the proportionality limit of the workpiece material. That is, when the load is removed, the dimensions of the workpiece remain unchanged. The paper presents the experimental device designed to determine the axial force and torque when drilling holes in the stress-strain workpiece material. Multi-factor experiments were carried out to obtain empirical dependences of the axial force and torque arising in drilling holes in the stress-strain workpiecematerial on the process parameters.

Сверление отверстий - одна из распространенных операций при изготовлении деталей. Вследствие этого повышение эффективности данного процесса является актуальной задачей. Для повышения эффективности процесса сверления на базе Юго-Западного университета был разработан способ сверления в предварительно напряженно-деформированном материале заготовки, который подвергают упругой деформации нагрузкой, не превышающей предела пропорциональности материала заготовки. После снятия нагрузки размеры заготовки остаются прежними. Было показано, что при таком способе сверления наблюдается уменьшение осевой составляющей силы резания от 20 до 30%. Причиной этого является то, что в зону резания, а именно в зону первичных деформаций, материал заготовки будет поступать, находясь в предварительно деформированном состоянии, которое способствует насыщению кристаллической решетки обрабатываемого металла энергией. В рамках представленной работы было выполнено моделирование процесса сверления заготовок из цветных сплавов в предварительно упругодеформированном состоянии. Особый интерес при раскрытии механизма этого явления представляют исследование и описание изменения зоны предварительного упругодеформированного состояния обрабатываемого материала на различной глубине сверления. Исследование было выполнено в среде конечно-элементного анализа DEFORM-3D, которое показало, что упругодеформированное состояние обрабатываемого материала будет обеспечиваться в зоне резания на протяжении всего времени обработки Drilling holes is one of the most common operations in the manufacture of parts. As a result, increasing the efficiency of this process is an urgent task. To improve the efficiency of the drilling process, we developed a method for drilling in a pre-stress-strain material of the workpiece, which is subjected to elastic deformation by a load not exceeding the proportionality limit of the workpiece material. After removing the load, the dimensions of the workpiece remain the same. We show that with this method of drilling, a decrease in the axial component of the cutting force from 20 to 30% is observed. The reason for this is that the workpiece material will enter the cutting zone, namely the primary deformation zone, being in a pre-deformed state, which contributes to the saturation of the crystal lattice of the metal being processed with energy. Within the framework of the presented work, we carried out the modeling of the process of drilling workpieces from non-ferrous alloys in a pre-elastically deformed state. Of particular interest in the disclosure of the mechanism of this phenomenon is the study and description of changes in the zone of the preliminary elastic-deformed state of the processed material at different drilling depths. This study was carried out in the DEFORM-3D finite element analysis environment. Thus, it can be argued that the elastically deformed state of the processed material will be provided in the cutting zone throughout the entire processing time