PARAMETERS AFFECTING THE TEMPERATURE OF THE DIAMOND CUTTING DISC WHEN CUTTING BUILDING MATERIALS

Abstract

The cutting of natural and artificial building materials is most often carried out with metal-based diamond cutting discs at cutting speeds of the order of 50-80 m/sec. The cutting process is accompanied by considerable heat release and heating of the diamond disk. At a temperature of about 600ºC, the tensile strength of a disc is reduced by a factor of 2 and graphitization of diamond grains occurs. Thus, when cutting stone and building materials with a diamond circle, the disk heating temperature should not exceed 600°C. In the work, mathematical modeling of the heating of a diamond cutting disk on a metal base was performed while cutting ceramic materials to determine the time of continuous operation to a critical temperature of 600°C. The simulation results presented in the graphs showed the dependence of the heating temperature of the disk on the diameter of the latter, the speed of rotation, the minute feed, the grain size and the thickness of the disk. Almost all elements of the cutting modes affect the disk temperature, although to a different extent. The vertical feed has the greatest influence. With an increase in the diameter of the cutting disk and a decrease in the rotational speed, the total cutting force, power and heating of the disk in 1 min. and increase with one revolution. The operating time to the critical temperature is significantly reduced. With an increase in the thickness of the cutting disk, the total force and cutting power increase. The simulation results showed that the grain size of the cutting disk significantly affects the important parameters of work. Therefore, if there are no special requirements for surface roughness, it is more profitable to work with a coarser-grained disk. According to the simulation results, it can be said that in order to ensure the maximum thermal resistance of the disk, it is necessary to choose disks with a grain size of at least 25 and work at a vertical feed rate of no more than 0.05 m/min. It is shown that by selecting appropriate process characteristics the time of continuous operation can be of the order of 10 ‒ 12 min without the use of forced cooling.