Several Notices for Bending Process of Hardware - PTJ Blog

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Several Notices for Bending Process of Hardware


Rocessing technology and precautions of folding


1) Processing range of bending:

The distance from the bending line to the edge is more than half that of the V-groove. For 1.0 mm material, the minimum distance is 2 mm when the lower die of 4V is used.
Note: If the inner dimension of the folding material is smaller than the minimum one
in the table above, the folding machine can not be
processed in the normal way.
At this time, the folding edge can be lengthened
to the minimum one, and then trimmed after bending, or die processing can be considered.

2) When bending the bending machine, due to the size of the hole edge to the
bending line is too small, appropriate processing must be done
bending line is too small, appropriate processing must be done at this time:

  • (1) LASER is secant on the corresponding bending line.
  • (2) NCT line pressing on the corresponding bending line (this
  • method is preferred).
  • (3) Enlarging the hole to the bending line (this methodmust be confirmed with the customer ).
Note: When the distance between the holes near the bending line and the bending
line is less than the minimum distance listed in the
table, deformation will occur after bending.

3) Reverse flattening:

When the convex hull is opposite to the square direction of reverse bending, and the distance from the bending line is less than 2.5t, the flattening will cause the convex
hull to deform. Process treatment: before
flattening, a fixture is put under the workpiece, the thickness of the fixture is slightly greater than or equal to the height
of the convex hull, and then
the flattening die is used to flatten it.

4) When the hole is too close to the bending line (<3T+R),it must be pressed or secant at the bending line to avoid deformation of the hole when bending.

5) Plating Workpiece

Bending of electroplated workpiece must pay attention to indentation and coating shedding (special description should be given on engineering drawings).  

6) segment difference

According to the forming angle, it can be divided into straight-edge fault and oblique-edge fault. The processing method depends on the height of the fault.
Straight edge breakage: When the breakage height h is less than 3.5 times the material thickness, the breakage die or easy die forming is adopted, and when the material thickness is greater than 3.5 times, the normal one positive one negative two folds are used to complete the breakage Inclined edge breakage: When the length of inclined edge is less than 3.5 times the thickness of material, it is formed by breakage die or
easy die, and when the thickness is greater than 3.5 times, it is completed by normal one positive one negative two folds.

7) riveting electrostatic Guide

When the distance between the edge of the electrostatic guide rail and the bending line is more than 1+V/2mm (V is the width of the lower die V slot of the folding bed), the electrostatic guide rail can be riveted first and then bended. When the distance between the edge of the electrostatic guide rail and the bending line is less than 1+V/2mm, the electrostatic guide rail must be riveted first and riveted again. As shown in the figure below, the material of 1.2mm can be riveted by 5V. Note: The width of electrostatic guideway is 7.12mm, model: 700-02776-018) thin material, with strong elasticity.

Or the bending angle is very important. Usually we can consider pressing line on the bending line, or opening process holes on the bending line or pressing reinforcing bars on the bending line. In order to avoid springback after bending, resulting in dimensional errors. If easy-to-die processing is designed, springback must be taken into account.

9) pressing convex hull

When the convex hull is easy to press, if the height of the convex hull is very strict, the back pressure method can be considered to ensure its accuracy.

10) Die specifications for bending press triangle strengthening triangle strengthening:
There are two kinds of triangular reinforcement forming:
1. Share with bending tool, that is, bending and triangular
reinforcement are processed simultaneously.

2. Workpiece bending and then pressing triangle reinforcement.
Note: The number of triangular reinforcement is related to
the number of moulds. As can be seen from the table above, at present the same
specification can be formed in four places at most. If it exceeds this number,
it must be solved through consultation with the relevant personnel.

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