Štefan Barcík

INFLUENCE OF HIGH ENERGY TREATMENT ON WEAR OF EDGES KNIVES OF WOOD-CUTTING TOOL

Belarusian State Technological University Department of Physics, Information Technology Faculty, Minsk, Republic of Belarus Belarusian State Technological University Faculty of Chemical Engineering and Technology Department of Chemistry, Electrochemical Production Technology and Materials for Electronic Equipment Minsk, Republic of Belarus Belarusian State Technological University Faculty of Forestry Engineering and Wood Technology Department of Woodworking Machines and Tools Minsk, Republic of Belarus Belarusian State Technological University Faculty of Forestry Engineering and Wood Technology Department of Material Science and Metal Technology Minsk, Republic of Belarus Technical University in Zvolen Faculty of Environmental and Manufacturing Technology Department of Machinery Control and Automation Zvolen, Slovak Republic DOI : 10.17973/MMSJ.2016_12_201683 e-mail: chayeuski@belstu.by

Optimization of the Cutting Process of Wood-Based Agglomerated Materials by Abrasive Water-Jet

Abstract This paper deals with the cutting MDF, OSB, and plywood boards by abrasive water-jet (GMA Garnet Australian, grain size 80, MESH = 0.188 mm), with a kerf width depending on the material properties and technical parameters (material thickness, cutting direction, abrasive flow, and feed speed). The entry of water-jet cutting in the longitudinal direction produces changes in the material due to lateral leads spreading the width of the cut joints by an average of 0.20 mm for MDF boards, 0.3 mm for OSB boards, and 0.17 mm for plywood. On the exit side of the material, the water has the opposite effect. In relation to the thicknesses of the material, the width of the cut joints increases. The experiment has shown that the optimum value of the feed speed is explicitly 400 mm.min-1, at which the kerf width reaches the lowest dimensions both at entry and exit, and the abrasive flow of 450 g.min-1 has been shown as optimum. Kivonat A faalapú agglomerált anyagok folyadéksugaras vágásának optimalizálása. E tanulmány az MDF, OSB és rétegelt lemezek abrazív szemcsés folyadéksugaras vágásának problémájával foglalkozik (GMA Garnet Australian, 80-as szemcseméret, 0,188 mm szitaméret), az anyagtulajdonságoktól és műszaki paraméterektől (anyagvastagság, vágási irány, szemcsekoncentráció és előtolási sebesség) függő vágásrés mérettel. A folyadéksugár longitudinális irányú belépése változásokat okoz az anyagban, mivel ez oldalirányban jobban szétteríti a vágásrés szélességét, MDF esetében átlag 0,20 mm-rel, OSB-nél átlag 0,30 mm-rel, rétegelt lemeznél pedig átlag 0,17 mm-rel. Az anyag kilépési oldalán a víz ezzel ellentétes hatást fejt ki. A vágásrés szélessége az anyagvastagsággal növekszik. A kísérletek megmutatták, hogy kimondottan a 400 mm/min előtolás az optimális, melynél a vágásrés szélessége a legkisebb a bemeneti és a kimeneti oldalon egyaránt. Szemcsekoncentráció tekintetében 450 g/min bizonyult optimálisnak.

Effect of Temperature of Heat Treatment on Energetic Intensity of Flat Milling of Picea Abies

Abstract The paper deals with the research of the influence of thermal modification temperature of spruce wood on the electric energy consumption of its face milling. Samples of spruce wood heat treated at temperatures of 160, 180, 200 and 220°C were milled at the cutting speed of 20, 40 and 60 m.s-1, the feed rate of 6, 10 and 15 m.min-1, the rake angle of 15° with the depth of the cut of 1 mm. The energy consumption was evaluated from the cutting power, which was based on the difference during milling and idle cycle. The analysis of variance showed a decrease in cutting power with an increasing temperature of thermal modification. The average cutting power value is 137.7 W at the native sample and 80.8 W at the sample treated at 220°C. The Duncan’s test of statistical significance has shown that the thermal modification has a statistically significant effect on the cutting power values.

Influence of Technological Parameters on Tool Durability during Machining of Juvenile Wood

This work examined differences encountered when machining juvenile wood vs. mature wood. Difference in the blunting of the cutting tool when processing types of juvenile and mature wood from pine (Pinus sylvestris L.) and poplar (Populus tremula L.) were studied. The experimental model process included milling at various feed (2.5 and 15 m∙min-1) and cutting speeds (pine 20 m∙s-1, poplar 30 and 60 m.s-1), at various angle geometries (rake angle, cutting edge, and clearance angle). The blunting of cutting edge was measured after milling at 100, 300, and 500 meters on milling machine with the lower spindle. The results showed that milling of juvenile wood gives a longer technical lifetime for cutting instruments than milling of mature wood.

Impact of Selected Technological, Technical, and Material Factors on the Quality of Machined Surface at Face Milling of Thermally Modified Pine Wood

The impact of technical and technological parameters on the quality of machining during milling of thermally modified pine wood (Pinus sylvestris L.) was studied. Experiments were conducted to evaluate the effects of tools (α = 30°, β = 45°, γ = 15°, 20°, and 30°), material (natural material, thermally treated at 160 °C, 180 °C, 210 °C, and 240 °C), and technological factors, such as cutting speed (20 m.min-1, 40 m.min-1, and 60 m.min-1) and feed rate (6 m.min-1, 10 m.min-1, and 15 m·min-1) on the quality of the machined surface (standard deviation of surface Ra). The roughness measurements were realized by a non-contact method using a laser. This paper aimed to highlight which one of the technological or tool factors had the greatest impact on the quality of the surface of heat-treated wood in face milling. The importance of the parameters impact on surface quality was in the following order: rake angle, feed rate, thermal treatment, and cutting speed.

INFLUENCE OF THERMAL MODIFIED PINEWOOD ON THE QUALITY OF MACHINING AT PLAIN MILLING

Article assess the effect of thermal modification on the surface roughness (Ra) after the face milling of pinewood (Pinus sylvestris) at different cutting conditions. The experiment was performed with samples modified at four temperatures (T = 160 °C, 180 °C, 210 °C and 240 °C), at three feed speed (vf = 6, 10 , 15 m.min-1), at three cutting speeds (vc = 20, 40, 60 m.s-1) and at positions of three angles (γ = 15°, 20°, 30°). The roughness measurement was executed by a non-contact method using a laser profilometer LPM 4. It was found the importance of influence of studied factors affecting the surface finish in the order: heat treatment, feed speed, cutting speed, angular geometry.