Carbide Saw Blade Sharpening Technology

When sharpening carbide saw blades, you can use a universal sharpener or a special automatic saw blade sharpener. With an automatic saw blade sharpener, all operations (including the dressing of the tool steel tooth backs) are done automatically, while with a universal sharpener it must be done in one step.

1 Low carbon tool steel tooth back sharpening

The serrations of the carbide-tipped circular saw blades should be higher than the back of the saw body, generally 0.2 to 0.3mm higher. Grinding front diametrically dressing tool behind the teeth of the hacksaw blade body. Grinding tool steel tooth back can not use diamond grinding wheel, but use silicon carbide or corundum grinding wheel. In order to avoid excessive temperature, the sharpening thickness is not too deep, and the amount of dressing and sharpening is in the range of 0.5 ~ 1.0mm. The back angle of the teeth of the blade is 5-10° larger than the back angle of the sawtooth. If the back angle of the sawtooth is 20°, the back angle of the teeth of the low carbon tool steel saw blade is 25 to 30°.

2 Rear tooth surface sharpening and diameter correction

Carbide insert welding tooth circular saw blade can sharpen the front flank, rear flank and flank of the tooth. The use of the saw blade and the experimental test results show that the wear of the rear tooth surface of the circular saw blade is more serious than that of the front tooth surface, so the rear tooth surface should be mainly sharpened when the saw blade is sharpened. The circular saw blade used for simple sawing can only sharpen the rear tooth surface, and the saw blade used for cutting veneer or melamine and PVC clad wood-based panels, the rear tooth surface and the front tooth surface need to be sharpened, but generally in the After sharpening the rear tooth surface 3 to 5 times, sharpen the front and rear tooth surfaces at the same time.

The rear tooth surface sharpening is also the process of accurate radial correction of the saw blade. In order to make the saw tooth angle parameters meet the needs of actual production, the saw teeth after radial sharpening of the circular saw must be highly consistent with the original saw tooth angle parameters, and the grinding wheel should be The plane is completely parallel to the rear tooth surface, and the grinding wheel plane is fed laterally according to the original rear angle of the saw blade. The circular saw blade with alternating oblique grinding teeth should be sharpened for the first time for every other tooth, and then the remaining teeth should be sharpened. At this time, the grinding wheel should be adjusted to the opposite direction and the same angle. Sharpen again.

After sharpening, the tooth surface should be kept consistent in the radial direction through the relative circular motion of the circular saw blade and the grinding wheel according to the wear degree of the saw blade. In order to ensure sufficient sharpening amount, after regrinding the rear flank of each tooth, a newly ground facet with a width greater than 0.2mm must be obtained.

3 Front tooth surface sharpening

The actual machining test shows that the main edge retreats after the front flank of the saw tooth is worn to a certain extent, and a wear band with a certain width appears on the front flank. Therefore, it is very necessary to sharpen the front and rear flanks at the same time after sharpening the rear flanks for 3 to 5 times. When sharpening the front tooth surface, the plane of the grinding wheel should be parallel to the front tooth surface, and the sawtooth feeds tangentially or radially relative to the grinding wheel to keep the original rake angle of the sawtooth unchanged, as shown in Figure 3. Since the thickness of each tooth is about 1/4 of its length, the amount of sharpening should not be too large, otherwise the service life of the saw blade and the width of the saw blade will be greatly reduced.

4 Grooved tooth sharpening

When sharpening the saw teeth with concave surface, grinding rollers can be used. The diameter of the grinding rollers can be changed according to different saw widths, and the particle size is W50 or W35. The edges of the grinding rolls can also be sharpened, but must be accurately centered.

5 tooth flank sharpening

Carbide-welded tooth circular saw blades generally only sharpen the front and rear tooth surfaces, but do not sharpen the flanks of the saw teeth. TP sawtooth, with the increase of the number of sharpening of the rear tooth surface, the sawtooth shortens, and the chamfer at the top of the sawtooth gradually disappears. At this time, the side of the tooth must be sharpened to supplement the saw material angle. When sharpening, the plane of the grinding wheel and the top surface of the sawtooth should be inclined at an angle of 20° to 30° and sharpen tooth by tooth, and then turn over the carbide-tipped circular saw blade and repeat the sharpening on the other side.

6 Selection of sharpening amount

If the grinding wheel speed is too high, the self-grinding performance of the grinding wheel will be poor, the tensile stress on the surface of the saw teeth will be large, and adhesion will easily occur. If the temperature of the grinding zone is too high, the cutting edge will be Cracks occur on the grinding surface, reducing the service life of the saw blade. The sharpening parameters of YG carbide tools for wood cutting are as follows: the linear speed of the grinding wheel is 16-18m/s, the relative feed speed of the grinding wheel and the saw blade is 1.0-1.5m/min, and the amount of each sharpening is 0.01-0.02mm. In the absence of coolant supply, resin-bonded grinding wheels should be used, and the grinding wheel feed rate and sharpening amount should be reduced by half. In actual operation, the amount of sharpening can be judged by the number of sparks that appear after the grinding wheel and the sawtooth are in contact with each other. Adjust the sharpening parameters to continue sharpening, it is advisable to have 3 to 4 sparks per sharpening, and 1 to 2 sparks per sharpening in the third round of sharpening, and the tooth surface of the teeth after being sharpened The surface roughness can meet the requirements of use.