Disc harrow working parts

It is a rake group with concave discs mounted in series on a shaft at a fixed distance. The concave surface of the disk is generally spherical, and some countries also use conical surfaces. There are two types of discs: full-edge blades and notched blades. The former is simple to manufacture and easy to sharpen; the latter has a strong ability to penetrate into the soil and is helpful for cutting up soil clods and residual weeds. It is mostly used on heavy-duty rakes for tilling heavy soil. The sizes of rake blades have been standardized in various countries and there are international standards. The material of the rake blade is generally wear-resistant 65Mn steel, or low-carbon martensitic B5 steel. Since the 1940s, the United States has used cross-rolled steel plates to manufacture rake blades. The center hole of the disc rake blade is generally a square hole, which is separated by an intermediate tube. The rake blade and the intermediate tube are placed on the square shaft and locked with a nut to form a rake group. When working, the disc cutting edge plane is perpendicular to the ground and forms an angle with the forward direction. Each rake group is supported by bearings on the frame. During operation, under the action of tractor traction and soil reaction force, each rake blade of the rake group rolls along with the square shaft as a whole. Under the action of the rake's own gravity, the rake blade cutting edge cuts into the soil, cuts off grass roots or crop residues, chops the tilled strips, and makes the soil strips rise slightly along the concave surface of the rake blade, and then turns over, with a certain amount of soil turning and covering. effect. The deflection angle of the rake group can be adjusted, and the adjustment range is generally 0° to 30°, and the commonly used deflection angle is 10° to 25°. Increasing the deflection angle can increase the depth of the rake blade into the soil and the effect of turning and breaking the soil, and the resistance will also increase.