There are two kinds of fatigue cracks on the blade of the wood shredder, namely the cracks perpendicular to the cutting edge and the cracks parallel to the cutting edge. These two kinds of cracks can occur on the tool surface of the alloy, and may also appear on the tool flank of the alloy blade base.
The first kind of crack is mainly caused by thermal fatigue effect, which is earlier than the change of cutting force and the other varieties with long crack wood work related: then you need to participate in the cooling liquid in the destruction, in order to reduce the occurrence of the blade when cutting heat to alloy blades occurred adverse effects. The change rule of the blade temperature with the time is related to the heating of the blade, that is to say, the method is decided by the damage method. Turning and drilling, in the determination of the time of continuous natural damage, in the blade and workpiece touching parts of the highest temperature, and showed a linear upward trend, the touch parts of the temperature is usually in a state of chaos. Due to the destruction of wood, the blade and wood workpiece touch time is very short, usually only a few milliseconds, so the destruction of heat only affects the workpiece touch surface within the range of about 1mm. Two pin holes, in which a hole is strung on the pin shaft, can be rotated to use four corners to operate.
In the process of crushing and blowing, coating welding, surfacing tungsten carbide or welding a special wear-resistant alloy, to extend the service life, but the production cost is higher. The four corners were made into trapezoid, arris and sharp angle, advancing their destructive effect on forage fiber feed, but their wear resistance was poor. The annular blade has only one pin hole, and the work angle is changed actively during the operation, so the wear is uniform and the service life is longer, but the structure is messy.
The method of placing the blade on the rotor is related to the balance of the rotor, the dispersion of the material in the crushing and blowing room, and the uniform degree of the blade wear. The requirements of blade placement are as follows: the movement track of the blade is not repeated as much as possible, and the movement track of the blade is uniformly distributed along the crushing and blowing chamber, and the material is not arranged to one case, which is beneficial to the dynamic balance of the rotor.
