Investigation of Cutting Performance of a Circular Saw Blade Based on ANSYS/LS-DYNA

The circular saw blade is widely applied in rock processing; its cutting performance significantly impacts rock processing. Therefore, the numerical simulation model of rock cutting with the flexible circular saw blade has been established to investigate the effects of cutting parameters on the stress and cutting force of circular saw blade, and the damage and stress of rock in the circular saw blade cutting into rock vertically at constant feed speed and rotation speed. The research results indicate that the stress of the saw blade and rock rises with the increase of feed speed and rotation speed of the saw blade. Furthermore, the rock damage and the cutting force of the circular saw blade increase with the increasing feed speed and decrease with increasing rotation speed. The circular saw blade cutting force, vertical force, and horizontal force increase with the rising distance between the double circular saw blade. However, the axial force decreases. The research results of cutting hard rock with the flexible circular saw blade can aid in the optimization of cutting parameters and improve cutting efficiency.

IMPROVING THE PERFORMANCE OF MINERAL CERAMIC BLADE CUTTING TOOLS

The article considers the possibility of improving the performance of mineral-ceramic cutting plates by removing most of the defects on their working surface due to the formation of functional surface layers by ion-vacuum treatment. A model of a surface-hardened layer for VOK-60 type ceramics is proposed. Based on the configuration model of the substance, chemical elements are selected for modifying the surface layer of ceramics. The results of laboratory and production tests that showed an increase in the performance of ceramic plates after implantation by at least two times are presented.

Effect of thermal modification temperature of spruce wood on cutting parameters during circular saw blade cutting

Effect of thermal modification temperature of spruce wood on cutting parameters during circular saw blade cutting. The work examines the effect of temperature on energetical parameters (specific cutting resistance and cutting force) when cutting heat-treated wood of Norway spruce (Picea Abies) by a circular saw. The test samples were heat-treated at 160°C, 180°C, 200°C and 220°C. One sample was not heat treated and was used as a reference sample. In comparison with the theoretical assumptions, the influence of temperature on the cutting force and specific cutting resistance was confirmed. With increasing temperature of modification, the specific cutting resistance and cutting force decreased. The reduction of value of cutting force is related to changes in the chemical structure of the wood components, weight and density loss due to the increasing temperature of modification.

Modeling of Non-Stationary Processes When Cutting Hard-to-Process Materials

In the conditions of high-speed processing of parts of complex configuration, with a large end and longitudinal length, from hard-to-work steels and alloys, it is difficult to ensure the wear resistance of the cutting tool in the aisles of one technological passage. To ensure the appropriate quality indicators of the surface layer, it is impossible to replace a worn-out cutting tool. In connection with the above, the problem of ensuring the operability (wear resistance) of the cutting tool is acute. The results of theoretical and experimental studies of contact phenomena in blade cutting based on the thermodynamics of non – equilibrium processes and from the standpoint of self-organization of the tribosystem are presented. the developed thermodynamic model of blade processing with variable cutting modes (non-stationary) allows to minimize the wear of the cutting tool and generally increase production efficiency by accelerating the drive of the main movement of the metal-cutting machine.

Modeling of Thermophysical Phenomena When Cutting with Coated Tools

The results of computer simulation of thermophysical phenomena in the contact zone during blade cutting of metals with multi-layer composite wear-resistant coatings that ensure the adaptability of the cutting wedge to friction conditions are presented. On-site experimental studies of the cutting temperature during turning with various coatings, structural-phase analysis of the surface layer of the cutting tool to explain the mechanism of formation of secondary structures with a shielding effect – the effect of selforganization.

pH-RESPONSIVE WOOD SLICES FOR THE CONTINUOUS SEPARATION OF LIGHT OIL/WATER/HEAVY OIL TRIPHASE MIXTURES

Light oil/water/heavy oil triphase mixtures are common in industrial wastewater, while nearly all separation materials with superwettability can only separate biphase mixtures of light oil/water or/and heavy oil/water. Here, a balsa wood slice with superhydrophilic/superoleophilic property in air was fabricated by a blade-cutting and ethanol-treating process. Therefore, the slice could be dually prewetted with both water and oil and thus showed underwater superoleophobic and underoil superhydrophobic properties without any further chemical modification. Such a slice showed underoil superhydrophobicity in nonbasic environment while transition into underoil superhydrophilicity under basic condition. Combining with the porous structure possessed by wood designed to transport liquids, this superwettability of the treated wood slice could be leveraged in the continuous separation of light oil/water/heavy oil triphase mixtures only driven by gravity with a high permeation flux and separation efficiency. After each separation, the slice was easily recovered by washing with acidic solution, and it could be recycled up to 15 times without any loss of pH responsibility. During repeated cycling separation, the slice exhibited excellent separation stability.

Hydrostatic Bandsaw Blade Guides for Natural Stone Cutting Applications

Bandsaws either use fibre or ceramic block or sealed bearings as blade guides. This works well for cutting metals, wood and plastics. However, highly abrasive particles generated while cutting stones, settle between the contacts of the blade and the guides causing wear and premature failure. Hydrostatic guide system as presented in this work, is a contactless blade guiding method that uses force of several pressurized water jets to keep the blade cutting in a straight line. For this investigation, cutting tests were performed on a marble block using a galvanic diamond coated bandsaw blade with the upper roller guides replaced by hydrostatic guides. The results show that the hydrostatic guides help to reduce the passive force to a constant near zero in contrast to the bearing guides. This also resulted in reduced surface roughness of the stone plates that were cut. Additionally, it has also been shown that using hydrostatic guides the bandsaw blade can be tilted to counter the bandsaw drift. This original research work has shown that the hydrostatic guide systems are capable of replacing and in fact perform better than the state of the art bearing or block guides specially for stone cutting applications.

MODELING OF THERMOPHYSICAL PHENOMENA

The results of the computer modeling of thermophysical phenomena in the contact zone during blade cutting of metals with multi-layer composite wear-resistant coatings are presented. These results ensure the adaptability of the cutting wedge to friction conditions. In-situ experimental studies of the cutting temperature during turning with various coatings and structural-phase analysis of the surface layer of the cutting tool were carried out to explain the mechanism of formation of secondary structures with a shielding effect - the self-organization effect.