Vol 45, No 6 (2016)

The spatial vibrations of a pipeline relative to the horizontal axis passing through the supports have been considered. The pipe contains transportable fluid and is surrounded by a viscous continuous medium. The Coriolis inertial forces, the Archimedes buoyant force, the forces of viscous resistance, and the forces related to the acceleration of the lateral motion of the pipe in the surrounding medium have been taken into account. The vibrations of the pipe occur under the action of variable internal pressure that varies according to the harmonic law. The vibration regimes are analyzed with respect to the particular values of the parameters.

The problem of the structural synthesis of a mechanism for converting rotational motion into reciprocating rotary motion has been considered. In accordance with the synthesis conditions and the found solutions, a planetary mechanism with elliptical gears has been proposed and its kinematic analysis has been performed. It has been shown that the rocking angle and the asymmetry factor of the working stroke of the mechanism depend on the selection of the eccentricities of elliptical gears.

A methodical approach and program for calculating the kinetics of flat crack extension with an arbitrary front configuration in the spatial elements of constructions have been developed. The technique creates possibilities to estimate cyclical growth and changes in the front configuration at an arbitrary distribution of stresses. The experimentally calculated method of estimating the crack dimensions has been stated. The example of calculating a crack in the pipeline in the presence of residual stresses and taking into account T stresses is presented.

The shear strength of plasma-sprayed electroinsulating Аl₂O₃ coating has been determined for blanket modules of a thermonuclear reactor in a friction couple with 316L(N)-IG steel and BrAZhNMts9-4-4-1 bronze. An analysis of the experimental and calculated data on the influence of shear stresses on the electric insulation of blanket modules has revealed the need to decrease the coefficient of friction to permissible level [f] = 0.28 in the range of contact pressures Р = 3–500 MPa.

One of the most promising methods of manufacturing axisymmetric parts of gas turbine engines is local deformation on specialized rolling mills. To design this class of manufacturing operations and equipment, it is effective to use physical and numerical modeling. The article has provided the method and results of physical and numerical finite-element modeling of local deformation process of a detail of a cone-with-cylinder type made of EI962–Sh chromium steel. Analyses of the energy-power parameters of the technical process and the possibility of the destruction of a part during the deformation process have been carried out.

The article presents the results of an experimental test of the automatic system to control the adjustment and maintenance of resonance oscillations of a mechanical system. The oscillations of the mechanical system are excited under rotation of unbalanced rotors of two AC induction motors. The operation of the control system is based on the measurement of the phase shift between the oscillations of the mechanical system and the exciting force.