


Vol 36, No 9 (2016)
- Year: 2016
- Articles: 20
- URL: https://journal-vniispk.ru/1068-798X/issue/view/14002
Article



Plates in hydraulic presses with ohmic heaters
Abstract
The thermal calculation of plates in hydraulic presses with ohmic heaters permits the determination of the heater parameters and their configuration in the plate so as to minimize the temperature difference over the plate’s working surface. Determination of the surface power of the heater is considered by an analytical method (for axisymmetric systems) and by finite-element analysis (for systems of arbitrary configuration).



Automated machining of turbine blades
Abstract
A design method is proposed for automated processes used in the manufacture of gas-turbine blades. As an example, the manufacture of stator blades for a gas turbine is considered. A multifunctional numerically controlled grinding machine is used in the example.






Stress and strain concentration in weld-joint flaws
Abstract
Finite-element modeling is used to investigate the stress–strain state at the tip of a blunt weld-seam flaw. A multifactorial experiment yields formulas for the concentration coefficients and the stress and strain gradients in elastic and plastic deformation regions of the local zone.



Thermal distribution in the PTFE–steel frictional pair
Abstract
Research on the wear of a PTFE–18Kh2N4MA steel pair indicates that the heat-distribution coefficient calculated from the Sharron formula for the polymer is too low. The transfer of polymer to the steel must be taken into account in determining that coefficient.



Burnishing with wear-resistant mineral–ceramic and hard-alloy indenters
Abstract
Means of increasing the wear resistance of burnishing tools with mineral–ceramic and hard-alloy indenters are considered. Indenter designs that optimize the cost and quality of burnishing by means of a rigidly attached tool are discussed.



Dynamic stability of band saw machines
Abstract
The eigenfrequencies of the flexural–torsional vibrations of band saw blades and the limits of the instability regions are determined as a function of the tool parameters and the operating conditions. Analytical equations describing the dynamic stability regions of the plane form of the band saws are obtained.



Behavior of heat-resistant alloys and titanium alloys on cutting
Abstract
The properties of heat-resistant alloys used for the manufacture of compressor blades are analyzed. The optimal cutting speeds for titanium alloys and heat-resistant alloys are determined. The dependence of the plastic strain and chip formation on the cutting speed in the broaching of such alloys is established.






Automated 3D modeling of working turbine blades
Abstract
A method of automating geometric construction in the Siemens NX system is considered. In UG/Open GRIP interactive programming language, programs are written for modeling the structural elements of an uncooled working turbine blade. The programs are combined in a user application that creates 3D CAD models 70–90% more quickly than traditional NX tools.



Automated management of manufacturing orders
Abstract
Resource management in order-based manufacturing production may be organized in terms of the preliminary, planned, and actual cost of products. Approximate calculation of the preliminary cost of individual items (orders) is ineffective. That considerably impairs plant economics. The preliminary, planned, and actual cost of products may be calculated by means of methods and models incorporated in software for an integrated automated information system at a manufacturing enterprise, which has already performed well in Russia.












Recursive model of the blunting of an abrasive grain
Abstract
An algorithmic model is proposed for calculating the blunting area of an abrasive grain in grinding. The model permits prediction of the blunting of an abrasive tool in a broad range of operating conditions. It is recursive: the nonlinear feedback with respect to the blunting area itself is taken into account. The model permits prediction of the performance of abrasive tools in different conditions. That is especially important in manufacturing today.






Influence of the wire EDM conditions on the cut width
Abstract
The influence of the conditions of wire electric-discharge machining (EDM) on the cut width in the machining of 09G2S steel is experimentally investigated. The relation between the cutting power and the cut width is obtained. It is shown that, with reduction in the power, more thermal energy is concentrated at the machined section of surface, the probability of secondary spark discharges increases, and consequently the cut width increases.



Optimizing the high-speed drilling of small-diameter holes by core flat drills
Abstract
A model is developed for optimization of the high-speed drilling of small-diameter holes by core flat drills. Thanks to the structure of the model, the problem reduces to optimization of the process under constraints associated with optimization of the bit’s structure and geometry.





