Analysis of the chain-flail debarking using a high speed motion analysis system

Chain-flail delimbing-debarking technology is suitable for multi-tree proce ssing of small-diameter trees. In the chain-flail debarking process, the ro tation speed of the chain drum ranges 300-500 rpm. Therefore, a high-speed motion analysis is the only method to show what really happens in the debar king process. In this study, it was noticed that debarking occurs in a very short time (about 0.5 ms) when the chain hits the timber. If the chain hit s the side of the tree, the chain just slides on the surface of the tree an d is not able to debark the tree efficiently. In the determination of the i mpact force there is a clear correlation between the results obtained by a load cell mounted at the hitting point of the chain and those calculated us ing the impact time determined with a high-speed motion analysis system. Th is information makes it possible to determine the maximum impact force of t he chain without measuring it.