COMBINED EXTRUSION OF GLASSES WITH A CONICAL BOTTOM. METHODOLOGY FOR CALCULATING TECHNOLOGICAL PARAMETERS OF FREE EXTRUSION AT INITIAL DEFORMATION BY BENDING

All geometric formulas necessary for designing the process of extrusion of glasses with a conical bottom are obtained. Further, the obtained formulas will be used to develop scientifically based methods for calculating technological operations of free and constrained extrusion. The substantiation of the use of the wellknown methods of A. L. Vorontsov, developed for extrusion of glasses with a punch with a flat end, for calculating the deformed state of the workpiece is given.

PRINCIPLES OF APPROACH TO DETERMINATION OF TECHNOLOGICAL ELEMENT BASE FOR AUTOMATION OF MACHINING PRODUCTION PREPARATION THROUGHOUT CYCLE

The use in the practice of design works of technological preparation of production (CCI) of parameters of design quality of the main elements of integration of the design (checkpoint) element base prevents transition of CCI to information technology of automation of a certain level of solution of problems of practice throughout its cycle. This is manifested, in particular, in the fact that during the change of technological operations of transformation along their route, as well as between the stages of CCI and checkpoint, information and logical links of knowledge are objectively interrupted. When determining a continuous, flexible algorithm in the technology of automation of solving problems of CCI practice, significant difficulties arise. Concepts of existing knowledge were often not up-to-date, which hampered automation – a fast communication system was needed. The primary basis of automation is the formalization of knowledge. Insufficient formalization of knowledge (the content is descriptive) leads to the use of inefficient dialogue technologies, the work of which is organized with reference information in the electronic form of its display. To overcome these difficulties, the structure of the CCI knowledge base in its hierarchy is proposed for seven levels of basic objects of various types, it is based on formalized approaches. Knowledge objects are focused on the consistent and continuous solution of CCI practice throughout its cycle. The structure of all knowledge objects is based on its own technological element base, which is organic for CCI. Only on such an elementary basis can the main target functions of CCI be realistically achieved in solving the problems of its practice on their possible set.

Combined EXTRUSION OF GLASSES WITH A CONICAL BOTTOM. METHODOLOGY FOR CALCULATING TECHNOLOGICAL PARAMETERS OF CONSTRAINED EXTRUSION AT INITIAL DEFORMATION BY BENDING

The methodology for calculating the energy-power and deformation parameters of the process of constrained extrusion of glasses with a conical bottom part, starting with the bend of the workpiece. The extrusion of both non-hardening and hardening material is considered. In the latter case, the account of the hardening of the extruded material is described in detail. The above formulas allow us to determine such important parameters of the stamping process as total and specific deforming force, maximum pressure on the die wall, and an increase in the yield stress.

ALGORITHM FOR CALCULATING THE SURFACE ROUGHNESS PARAMETERS OF A PART MADE USING ADDITIVE TECHNOLOGY

The calculated dependences for determining the surface roughness parameters of a part made by selective laser fusion from materials that are certified and widely used in the aircraft engine industry are presented. A comparison of the values of the height parameters of the roughness obtained by calculation and on the basis of the experiment is presented. On the basis of the presented dependencies, a calculation algorithm is developed, which is the basis of the software for calculating on a computer.

IDENTIFICATION OF DEFECTS SIZES EDDY-CURRENT CONTROl

A method is proposed for identifying the size of defects during eddy testing, which reduces the zones of uncertainty caused by errors in calculation and experiment. In order to reduce the uncertainty, as a criterion for comparing the theoretical and experimental dependences of the signal on the defect, one can use the difference in minimization of the squares of the deviation of the corresponding dependences. Using the method of simulating the signal of an eddy current transducer (ECP) from a defect, experiments were carried out in order to verify the method for identifying a characteristic size, a defect, with subsequent calculation of the customer’s risk.

SWINGING OF THE LOAD ON THE TOWER CRANE AND PROBLEMS OF FIXING THE OSCILLATORY MOVEMENTS OF THE LOAD

The article considers the issues associated with the swinging of the load on the flexible suspension, the mechanical scheme of movement of trolley with load on the flexible suspension is represented, the processes start traveling mechanism of the trolley on a tower crane are investigated, the substantiation for the application of safety devices with the registration parameters fixed (register) load-swing is given, presented models of technical solutions to commit (register) load-swing.

ASSESSMENT OF THE STABILITY OF CARBON FIBER TO THE ACTION OF TRANSVERSE LOADS TAKING INTO ACCOUNT TIME AND CLIMATE FACTORS

The relevance of research in the development of physical methods for increasing the stability of products made of polymer composite materials (PCM) to the influence of environmental factors, taking into account its duration, is shown. The influence of exposure of carbon fiber samples on an epoxy matrix in the natural conditions of the climate zone of Saratov on the change in the limit stresses of three-point bending was studied. Comparative tests of samples premodified in a microwave electromagnetic field with a frequency of 2.45 GHz with an energy flux density (17…18)×104 µw/cm2 were performed. It is shown that the influence of environmental factors leads to a decrease in the limit stresses by (3,7…10,4) % depending on the exposure. Modification of carbon fiber in the cured state in the microwave electromagnetic field reduces the negative influence of the external environment by reducing the strength by (44.3…73) %. It was found that the strengthening effect of microwave modification increases with increasing exposure from 6 % to 11.5 % under the accepted experimental conditions, while the uniformity of the bending strength values in the batch increases significantly, which is manifested in a decrease in the coefficient of variation of limit stresses by (70.2…77.8) %. Functional dependencies in the form of 2nd-order polynomials are obtained, allowing with confidence (98…99) % predict the stability of products made of modified carbon fiber during long-term operation under the influence of environmental factors.

ODEL OF THE SHAPE OF THE CUTTING EDGES OF SPECIAL HOB CUTTERS FOR PROCESSING SHAPED HELICAL SURFACES

The article is devoted to the design process of a special hob cutter for processing helical surfaces, as well as the methodology for studying the shape of cutting edges using modern control and measuring equipment and the development of a model that allows one to study the effect of the number of regrinds on the shape of the processed surface.

MIXING PROCESSES AND EQUIPMENT. CONSTRUCTION MIXTURES AND MIXTURES FOR MANUFACTURING CONSTRUCTION MATERIALS. LECTURE 9

The article presents materials of Lecture 9 Theory of carrying and lifting, construction and road vehicles and equipment, which describes mixing machines, concrete mixtures, their dosage, quality and homogeneity. The process of concrete mixing and energy aspects of its production are described. The data on mixers used for producing mortars and clay suspensions are presented. The design of a special mixer for producing polystyrene-silicate mineralized granules and the production technology for hollow silicate spheres based on the working process of a special mixer are described.

COMBINED EXTRUSION OF GLASSES WITH A CONICAL BOTTOM. METHODOLOGY FOR CALCULATING TECHNOLOGICAL PARAMETERS OF THE TRADITIONAL PROCESS OF CONSTRAINED EXTRUSION

The methodology for calculating the energy-power and deformation parameters of the traditional process of constrained extrusion of glasses with a conical bottom part, including preliminary obtaining by molding the outer conical section of the bottom part of the product and the subsequent reverse extrusion of the glass with an internal cavity of the required geometry, is presented. The extrusion of both non-hardening and hardening material is considered. In the latter case, the account of the hardening of the extruded material is described in detail. The above formulas allow us to determine such important parameters of the stamping process as total and specific deforming force, maximum pressure on the die wall, and an increase in the yield stress.