ANALYSIS OF METHODS FOR ASSESSING THE STRENGTH OF STRUCTURAL MATERIALS OF WORKING ELEMENTS OF GRINDING MACHINES IN TERMS OF CRACK RESISTANCE
DOI:
https://doi.org/10.32718/agroengineering2025.29.141-144Keywords:
working element, grinding machine, beam sample, welded joints, deformationAbstract
This text provides a concise review of the components of grinding machines and the primary methods of grain grinding. It discusses the factors that contribute to the wear and failure of these components. Additionally, it outlines methods for assessing the strength of structural materials and their welded joints using beam specimens with a lateral crack, evaluated under cantilever and three-point loading conditions according to the crack resistance criterion (CR).
An analysis of the methods of cantilever bending of a beam with a lateral concentrator at the stage of fatigue crack initiation under an asymmetric cycle is carried out under the condition of cantilever bending of a beam specimen with a lateral concentrator, or three-point bending of such a specimen with a lateral concentrator in the seam, which is installed in the base and fastening unit. The value of K1 is obtained in the case of arbitrary e and a constant force P, respectively. It can be used to determine the functional characteristic of crack resistance K1s according to the described scheme of cantilever deformation of a beam with a lateral crack near the pinch point.
The strength of butt welded joints was assessed, and the schemes of three-point bending of a beam specimen with a lateral crack in the metal of the vertical weld of the butt welded joint were considered according to the strength criterion K1c. The determination of K1c of the weld metal of the welded joint was carried out when this weld and the crack in it are perpendicular to the base of the beam specimen.
Analysis of the proposed methods for determining the SIF according to the schemes of cantilever and three-point bending of beam specimens with a lateral crack in the material of the base of the specimen or the weld of the welded joint, respectively, are effective tools for ranking the strength of structural materials and their welded joints in the manufacture of parts of the working elements of grinding machines.
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