1. Bending Die
Typical dies consist of a middle plate, upper die, lower die, guide rail, lower die seat, etc. These types of dies are versatile and can handle most machining tasks.
2. Selection of Bending Dies
Different parts require the use of different dies. It is essential to have an understanding of the machining parameters of the machine tool and dies to select matching dies.
Machine tool parameters include: stroke, machining capacity, open height, middle plate type, etc.; die parameters include: upper die handle type (matching with the middle plate), pressure tonnage (maximum bending pressure), etc.
A. Selection of Machine Tool Parameters
1. Selection of Die Height
Stroke (mm) = Open height - middle plate height - upper die height - lower die seat height - (lower die height - 0.5V + t), where t is the thickness of the material (mm).
When selecting the lower die seat, it is also important to consider that there are various heights of lower die seats used to match different machining requirements.
Using different combinations of dies can achieve different die combination heights for processing different parts.
Selection of Die Parameters
1. Upper Die Handle Type
There are three forms of upper die handles to match different middle plates.
2. Upper Die Shape
Common standard shapes of upper dies include:
3. Upper Die Tip Radius and Tip Angle
Common tip radii for upper dies include:
(1) 0.2R
(2) 0.6R
(3) 0.8R
(4) 1.5R
(5) 3.0R
Selecting the appropriate tip radius: Generally, R0.6 is used for thicknesses below 3mm.
Standard tip angles for upper dies include: 90 degrees, 88 degrees, 86 degrees, 60 degrees, 45 degrees, 30 degrees, etc.
The die angle should be smaller than the bending angle. For example, when bending a workpiece to 90°, use a die with an angle of 88°.
4. Lower Die Form
Common lower dies come in single-V and double-V forms. Within these two types, there are segmented and integral types, suitable for different machining needs.
Generally, single-V dies have a wider range of applications than double-V dies, and segmented dies are more versatile than integral ones. Our company usually uses double-V and triple-V lower dies.
5. Lower Die V Width and V Groove Angle
The selection of the V groove in the lower die is related to the material thickness (T).
The V groove angle in the lower die should match that of the upper die.
