Generation and compression testing of spherical wood bodies

Abstract

ABSTRACT Spherical wood bodies included in the various objects or assemblies may be subjected to compression forces. On the other hand, there are several methods of obtaining spherical wood bodies by removing the material in chips. It is of interest, as such, to develop research that highlights the compression behavior of spherical wood bodies obtained as a result of the application of cutting processes. A machining method was selected taking into account the available research conditions. The selected machining method is based on the use of a rotary tubular drill and which performs a feed movement along a direction perpendicular to the workpiece rotation axis. Spherical bodies obtained from beech and ash were tested in compression using a factorial experiment with three independent variables at two levels of variation. The values of the compression force at which the cracking of the spherical wood bodies occurs were determined. The results of the experimental tests were mathematically processed. An empirical mathematical model was established to highlight the influence exerted by the wood material, the diameter of the spherical body, and the direction of the compression efforts to the direction of the wood grains on the force value from the moment of cracks.