ANALYTICAL CALCULATION OF THE MAIN PARAMETERS OF SMALL LOW RIGID CYLINDRICAL PARTS STRAIGHTENING BY TRANSVERSE BURNISHING BY FLAT PLATES

Abstract

The PURPOSE of the paper is determination of the main parameters of the straightening process of low rigid cylindrical parts by transverse burnishing by flat plates that include the permissible initial deflection of the workpiece, general deflection of the workpiece before the transverse burnishing and the degree of relative reduction. METHODS. The work uses the mathematical apparatus based on the laws of the theory of elasticity of a solid. RESULTS AND THEIR DISCUSSION. The analytical calculations resulted in the determination of the main parameters of the process of straightening cylindrical parts by transverse burnishing by flat plates. The general deflection of the workpiece before transverse burnishing depends on the width of the plate overhang, mechanical properties of material and workpiece dimensions. The ultimate initial deflection depends on the material, diameter and rigidity of the workpiece. The limiting relative reduction depends on the friction coefficient between the workpiece and flat plates. CONCLUSIONS. A scheme of transverse burnishing by flat plates is proposed for straightening of small low rigid cylindrical parts of the shaft and axle-type. The straightening is performed due to the elastic bending of the workpiece in the direction opposite to the initial residual deformation and change in the stressed state by workpiece rotation between the flat plates. The developed mathematical model provides reliable values of bending deformations that arise after the straightening of parts by transverse burnishing by flat plates. The analytical dependence for the calculated determination of the limiting initial deflection, general deflection under bending and the value of relative reduction can be recommended for practical use in industry to achieve the precision accuracy of low rigid parts of the shaft type.