Wyniki wyszukiwania - BazTech

1

Crossing axes of workpiece and tool at grinding of the circular trough with variable profile

Kalchenko V., Yeroshenko A., Boyko S.

Acta Mechanica et Automatica

|

2018

|

Vol. 12, no. 4

281--285

EN

In the article the method of grinding with crossed axes of the tool and the workpiece got further developed. The work discloses a method of processing details having an external surface with a profile in the form of an arc of a circle of variable radius (for example, rolls of pipe rolling mills). The particular three-dimensional geometric models of the processing, shaping and profiling of abrasive wheels have been developed. A method for controlling the grinding process, which ensures the removal of allowances along equidistant curves has been offered. The developed method of grinding provides a constant depth of cutting according to the coordinate of profile processing. This is achieved at the expense of the synchronous inclination of the wheel and its insertion by the size of the allowance. The diameter of grinding wheel affects on the maximum angle of orientation of the wheel has been proven. It has been shown that increasing the diameter of the abrasive wheel has led to a slight decrease in value orientation angle.

2

Increasing of energy efficiency of spindles with fluid bearings

Fedorynenko D., Sapon S., Boyko S., Urlina A.

Acta Mechanica et Automatica

|

2017

|

Vol. 11, no. 3

204--209

EN

Promising ways of energy efficiency gain of spindles with fluid flow bearings are offered. New design of journal hybrid flow bearing which contains spherical bearing pockets and adjustable valves with relay control system is offered to improve energy efficiency of spindle units of machine tools. To reduce power losses of fluid bearings at high speed special lubrication based on water with integrated system of corrosion protection is offered. Results of theoretical research of energy consumption of grinding machine tool with a new design of spindle hybrid bearings are presented. Power losses of the spindle unit with both new design and base design of journal bearings are assessed. Effectiveness of new design of spindle hybrid bearings at high operating speeds is shown.

3

Determination of cutting forces in grinding with crossed axes of tool and workpiece

Kalchenko V., Yeroshenko A., Boyko S., Sira N.

Acta Mechanica et Automatica

|

2017

|

Vol. 11, no. 1

58--63

EN

In the work the analysis of existent methods of determination of local and general forces of cutting at polishing of surfaces with a type as the arc of circumference is given. The dependence for determination of speed polishing and method for determination of thickness of the cut away layer on condition of equality of the tricked into and taken off volumes of material are offered. The method of determination of cutting forces, which takes into account cutting and deforming grain, is suggested. The method of determining the thickness of a cutting layer of one of the cutting edge, from the condition that the volume of material that is brought and is cut in each local point of contact spots has been proposed. The proposed method takes into account the compliance of the processing system and the discontinuity of the abrasive surface of the tool. By experimental way upper limits of thickness cutting layer when using different abrasive materials for a wide range of cutting speeds have been obtained.

4

Accuracy of spindle units with hydrostatic bearings

Fedorynenko D., Sapon S., Boyko S.

Acta Mechanica et Automatica

|

2016

|

Vol. 10, no. 2

117--124

EN

The work is devoted to the research ofprecision regularities in a spindle unit by the trajectory of the spindle installed on hydrostatic bearings.The mathematical model of trajectories spindle with lumped parameters that allows to define the position of the spindle with regard the simultaneous influence of design parameters, geometrical deviations ofform, temperature deformation bearing surfaces, the random nature of operational parameters and technical loads of hydrostatic bearings has been developed. Based on the results of numerical modeling the influence of shape errors of bearing surface of hydrostatic bearing on the statistical characteristics of the radius vector trajectories of the spindle by varying the values rotational speed of the spindle and oil pressure in front hydrostatic bearing has been developed. The obtained statistical regularities of precision spindle unit have been confirmed experimentally. It has been shown that an effective way to increase the precision of spindle units is to regulate the size of the gap in hydrostatic spindle bearings. The new design of an adjustable hydrostatic bearing, which can improve the accuracy of regulation size gap has been proposed.

5

The search of spatial functions of pressure in adjustable hydrostaticradial bearing

Fedorynenko D., Boyko S., Sapon S.

Acta Mechanica et Automatica

|

2015

|

Vol. 9, no. 1

23--26

EN

The analysis of spatial functions of pressure considering the geometrical deviations and the elastic deformation of conjugate surace have been considered. The analysis of spatial functions of pressure is performed by the finite element method. The difference of the size of pressure in a tangential direction of a pocket of a support under various service conditions has been investigated. A recommendation for improving of operational characteristics in regulated hydrostatic radial bearing has been developed.