Wuxi Smart CNC Equipment Group Co.,LTD
“Quality First, Customer First”
Smart CNC not only produce Press Brake, Laser Machine,Shear, Rolling Machine, also supply other complete sheet metal machine solution.
April 27, 2023
The following are the requirements and items for the welding quality of the shear blade:
Ⅰ.Check the strength of the weld: Use a green silicon carbide grinding wheel to grind the back of the shear blade, check the thickness of the weld layer, and the degree should be below 0.15mm. There should be no porosity and insufficient welding material at the bottom of the tip support. The length of the unfilled weld should not exceed 10% of the total length of the weld. If there are porosities, the blade will fall off during cutting.
Ⅱ.Check the position of the blade in the slot, such as blade displacement and droop exceeding the technical requirements. It should be rewelded.
Ⅲ.Check the welding strength of the blade: Tap the blade with a wooden hammer or a bronze hammer with moderate force, or tap the blade shaft with a hammer with strong force. The blade should not fall off from the slot to be qualified. The welding strength of the blade is not required to be checked one by one, and sampling can be used.
Ⅳ.Check the flatness of the blade: If there are obvious pits on the blade, it indicates that the blade is overheated and deformed. The blade should be burned down and rewelded.
Ⅴ.Check for cracks: After cleaning the blade with kerosene, if there are cracks on the shear blade of the shearing machine, the kerosene will penetrate into the crack and appear as a black line, which can be observed by the naked eye or a magnifying glass. The color penetration method can also be used: a solution is prepared by mixing 65% kerosene, 30% transformer oil, and 5% pine needle oil, and a little Sudan red is added. Place the blade part of the shear blade in the solution for 10-15 minutes, then rinse it with water, apply a layer of white clay kaolin, and observe its surface after baking. If there are cracks on the blade, the color of the solution will be revealed on the white clay, which can be seen with the naked eye. Blades with cracks cannot be used and need to be rewelded.
To adjust the shear blade clearance of the shearing machine, follow the steps below:
1.Remove the lower blade and clean it one by one.
2.The blade can be used on all four sides, select the good side and install it tightly. And check the flatness in the horizontal and vertical directions of the blade.
3.Remove the upper blade and clean it one by one. Similarly, the blade can be used on all four sides, select the good side and install it tightly. And check the flatness in the horizontal and vertical directions of the blade.
4.The upper blade is fixed and cannot be adjusted. We adjust the shear blade clearance of the shearing machine by adjusting the lower blade.
5.Find the two screws on the left and right sides of the lower blade to increase the clearance. Generally, they are on the outermost side.
6.Find the two tightening screws that push the lower blade to reduce the clearance. There is a locked backup nut on top of it, generally on the inner side.
7.Loosen the four bolts on the left and right sides of the lower blade table.
8.Lower the upper blade to the appropriate position manually, and the operator starts to adjust from the material feeding area of the shearing machine.
9.Use a plug gauge to make rough adjustments from the part where the upper and lower blades are not in contact on the left side to 0.5mm.
10.Manually move the trolley to move the blade to the middle position and adjust it to 0.5 millimeters for rough tuning.
11.Manually move the trolley to move the blade to the middle position between the upper and lower blades on the right side without disengaging, and adjust it to 0.5 millimeters for rough tuning.
12.Manually lower the slice to the appropriate position and begin fine tuning.
13.Use a feeler gauge to fine-tune from the part where the left upper and lower blades are not engaged until the feeler gauge can enter three wires but not five wires.
14.Manually move the blade to the middle position and start fine-tuning until the feeler gauge can enter three wires but not five wires.
15.Manually move the trolley to move the blade to the right side position where the upper and lower blades are not disengaged and begin fine-tuning until the feeler gauge can enter three wires but not five wires.
16.The above is for new cars and fine-tune until the feeler gauge can enter three wires but not five wires.
17.For old cars, fine-tune until the feeler gauge can enter ten wires but not twenty wires. Or adjust appropriately according to 1/10-1/20 of the required cutting sheet metal thickness.
18.If the blade edge of the shearing machine is sharp, and there are burrs on the edge of the cut sheet, the clearance between the upper and lower blades can be appropriately reduced.