Wood chipper, also called wood slicer, belongs to one of the series of wood processing equipment. It is widely used in the material preparation section in the production process of textile, paper, pulp, wood-based panels and other industries. The main cutting materials of this machine are small-diameter wood, bamboo, board and skin after peeling, and the remainder of felled fuel wood. However, for too thick (over 350mm), too thin (below 30mm), too short (below 250mm), too thin (below 5mm) and irregular materials (undifferentiated stumps, branches, etc.) Cut on the original basis, it has the function of layered cutting for insufficient bamboo slices with wall thickness less than 5 mm
Forestry machinery for cutting and processing residues from deforestation and wood processing into technical wood chips. Wood chips are mostly used as raw materials for pulp, hydrolysis and wood-based panels.
Classification
There are two types of wood chippers: stationary and mobile. The stationary type is mostly used in factories; the mobile type is usually used in forest areas and mountain farms. According to the layout of the working parts, it is divided into two types: drum chipper and disc chipper. According to the feeding method, there are two types of oblique feeding and flat feeding.
① Drum chipper. It is mainly used for cutting branches, small-diameter wood, veneer, slats, etc. with a diameter or thickness of less than 120 mm, and the cut wood chips are used as raw materials for fiberboard and pulp. Its cutting organization is a rotating drum on which several flying knives are installed. When the flying knives rotate, the wood is processed into technical wood chips. There are many square through holes on the outer edge of the drum, which can make the wood chips discharge smoothly; the feeding organization is composed of the feeding interface, the upper and lower feeding rollers and the feeding gap adjustment organization. Press it and feed it to the cutting structure at a certain speed to control the size of the cutting wood chips; when processing thick wood, it is adjusted by the feeding gap adjustment structure. After the wood chips are selected, the larger ones must enter the blade and the baffle again to be destroyed. The wood chips cut by this chipper are of lower quality.
② Disc chipper. It consists of cutter head, cutting knife, bottom knife, cutter head blade, etc. On the front of the cutter head, there is a groove for installing the cutting blade, which is arranged at an offset of 10 to 15 in the radial direction. There is a wedge-shaped adjustment block on the bottom of the blade to adjust the protrusion of the blade; the rear is equipped with a distance adjustment block to adjust the compensation length of the blade after sharpening. On the cutter head, there is a penetrating gap along the direction of the blade, and the cut wood chips can be turned to the other side of the cutter head. The outer edge of the cutter head is evenly equipped with blades, and the airflow generated by the blades blows the wood chips out of the discharge port. The machine has 3 types of small-knife, multi-knife and helical face knife. The first two kinds of wood chips have poor uniformity. Because the cutting surface of the helical face knife disc chipper is in contact with the cutter head during the cutting process, the unit The pressure is small, the wood chips are cut regularly, the broken wood chips are few, the cutter head wear is small, the length of the cut wood chips is the same, and the qualified rate of the cut wood chips can reach about 97%.
The production of wood chippers all over the world is now focusing on improving the cutting structure, the quality of the blade and the card loading method to reduce the time of sharpening and card changing. The reduction of global forest resources has promoted the development of mobile chippers in felling areas; and the selection of combined chipping machines in felling areas and whole-tree chipping machines will further improve the economic effect.