WOOD RESEARCH Volume 61, Number 3, 2016
Mariusz Reczulski

The system wood chipping in disc chipper – problems of uniformity of chips length

The system wood chipping in disc chipper Carthage-Norman in industrial plant in Poland was investigation, because there were problems with obtaining homogeneous length of chips. The knife height, wedge angle of knife, clearance angle (pull-in angle), spout angle, average log diameter and construction parameters of chipper have been measured. These parameters were used to determine analytical of average length of chips in the studied disc chipper – Carthage-Norman. Model in Matlab/Simulink for the computation of the chip theoretical length was used. Also carried out the calculation and simulation to determine the maximum and minimum length of chips that can theoretically occur while cutting wood in the studied chipper. Finally, the theoretical lengths of wood chips and the actual lengths produced during cutting were compared.

WOOD RESEARCH Volume 63, Number 2, 2018
Mariusz Reczulski

Optimization of the clearance angle in industrial disc chipper

Wood chips used for chemical pulp must be of relatively uniform size. The penetration of the pulping chemicals and thus the cooking time, is considerably determined by chip length. The clearance angle (pull-in angle) is a significant parameter of the knife positioning in the disc chipper, that affects the length of the chips.” In many production plants, this angle is wrong set depending on the diameter of the chipped wood. This causes problems in obtaining the appropriate length of the chips. The disc chipper in one of the industrial plants in Poland was investigated because it produced chips with smaller lengths from the assumed. This also included the numerical calculations to optimize the clearance angle. In the disc chipper, the variability of the clearance angle (α) along the cutting edge of the knife (helical knives) gives the possibility of improving the quality of the wood chips. Simulations to determine the variability of the clearance angle on the radius of the disc of chipper assuming the continuity of cutting wood in the chipper was also performed.

WOOD RESEARCH Volume 66, Number 4, 2021
Kidung Tirtayasa Putra Pangestu, Wayan Darmawan, Dodi Nandika, Imam Wahyudi, Lumongga Dumasari, and Hiroshi Usuki

Performance of coated tungsten carbide in milling composite boards

The purpose of this research was to analyze the performance (wear resistance, surface roughness, chip formation, and noise level) of AlCrN, TiN, and TiAlN coated tungsten carbides in cutting composite boards. The composite boards of wood plastic composite, laminated veneer lumber, and oriented strand board were cut by the coated tungsten carbide tools in a computer numerical control router. The results show that the differences in structure among the composite boards resulted in the difference in clearance wear, chip formation, surface roughness, and noise level phenomenon. The abrasive materials in wood plastic composite generated the highest clearance wear on the coated carbide tools tested. TiAlN coated carbide tool provided better wear resistance, smoother composite boards surfaces, and lower noise levels.

WOOD RESEARCH Volume 65, Number 6, 2020
Mariusz Reczulski

Optimization of cutting speed and clearance angle in the disc chipper

The wood chipping system in a disc chipper Carthage-Norman was studied. The study showed many operational problems related to obtaining chips of different length in the process of wood chipping. Excessive amount of fines and pin fractions were produced in the chipper. The reason for this was the too high cutting speed of the logs and the wrong clearance angle in the chipper. The actual and optimal distribution of the cutting velocity occurring on the chipper knife was determined using the Matlab/Simulink model. In addition, optimal clearance angles in the chipper were determined using the model.