CUTTING POWER DURING LENGTHWISE MILLING OF THERMALLY MODIFIED OAK WOOD

摘要

The paper presents experimental results of cutting power of thermally modified and non-modified hardwood of Summer oak (Quercus robur) during lengthwise milling. The process of heat treatment was performed in the atmosphere of superheated steam, at temperature 210 degrees C. Cutting power was determined during milling of the radial surface of modified and non-modified samples. It was calculated as the difference of power consumption by a milling machine during wood machining and at idling. Several cutting regimes were tested by combining different values of rotation speed, feed speed, rake angle and constant cutting depth a(e) = 1 mm. The values of cutting power are approximately the same at the kinematic angle of the tool head gamma = 15 degrees, 30 degrees; there are bigger differences for gamma = 20 degrees. The decline of cutting power in the thermally modified (210 degrees C) oak wood machining compared to natural oak wood is 21.7% divided by 22.2% at the cutting speed v(c) = 40 m.s(-1).