1. A vacuum is generated between the punch and the waste when stamping the product, and the waste is brought to the die surface when the punch rises
2, because of the stamping oil, the waste is stuck to the punching end face to the die surface
3, the friction of the waste and the die wall is not enough to overcome the impact of the punch and make the waste jump out of the die
When to prevent skip waste?
1, elastic material thickness and aluminum sheet blanking
2, the special requirements of customers, foreign customers as far as possible to add anti-jump waste device
Every cause has its effect. How can we prevent frequent waste jumping?
One, row with cutting mouth
Punching order: When the waste can be active in the concave die hole, the waste is easy to jump to the die surface because of the inertia of punching and the role of stamping oil, as shown in Figure 1, the first punching knife edge 1 and then punching knife edge 2, the small waste is able to move freely in the concave die, it is easy to jump the waste, so the cutting order should be the first punching knife edge 2 in punching knife edge 1
As shown in Figure 2, when there is a knife-edge, the knife-edge 1 with a process notch should be punched first, and then the knife-edge 2 should be cut. If the punching sequence is opposite, part of the small waste at the process mouth is easy to separate from the large waste, resulting in skip waste
② Continuous die in the final cut of the waste, because the waste is generally in the form of free movement, so we can add the thin material shrapnel on the knife edge of the dovetail, the role is to jam the waste to prevent jumping to the die surface, for the larger thick material can be directly used thimble
1. As shown in Figure 6 and 7, install a thimble that prevents jumping waste
2. What if I can't install a thimble?
① Circular punching in the end grinding bevel or convex points, the design of the drawing can not be drawn, test mold processing according to the actual situation, as shown in Figure 3
② For the regular narrow and long punching, R is generally convex on the punching end face, and a certain plane W is left between R and the end, and the drawing surface must be clearly expressed H=T, as shown in Figure 4 below
③ Make pores in the punching, blow waste with compressed air, as shown in Figure 5 below, fine holes can be processed by fine hole discharge
1. The use of anti-skip waste concave die, the principle is in the concave die knife edge wall there are two or three lines of the chute, the use of material extrusion deformation to increase the friction of the concave die wall, to prevent skip waste, hole shape is generally regular round square, etc., need to be customized
2. For thick pieces, skip waste during production, and pour R at the knife edge of the concave die, R=0.02-0.05, as shown in Figure 8 below
3. The die can be processed into an inverted cone (processed with an optical grinder) to increase the deformation of the material and prevent waste from jumping to the die surface.
In addition to the above methods, you can also increase the length of the punch into the die, or add a vacuum pump to the lower die to suck waste
Well, about how to prevent the method of jumping waste Xiaobian is here, I do not know that you have learned it?