Note on side trimming and side punching for stamping dies

Determine the installation height and position of the bevelled wedge through the cross-section

1) roughly determine the position of the punch and accurately determine the angle and position of the concave die set and the anti-rotation angle, according to the size of the fixed seat of the punch to determine the size of the working surface of the sliding wedge (determine the model of the sliding wedge

2) The slanting wedge is placed following the angle of placement on the die base and the position of the fixed seat of the punch

According to the die's actual situation, choose the punch holder's installation method

From the perspective of the balance of forces on the sliding wedge, the ideal way of fixing it is to control the force point of the punch in the centre of the sliding wedge as far as possible and to arrange the installation method of the fixed seat according to the actual situation in special cases; according to the fixed angle of the fixed seat of the punch, the approximate position of the sliding wedge in the plane of the die holder is determined.

 

   From the perspective of the balance of forces on the sliding wedge, the ideal way of fixing it is to control the force point of the punch in the centre of the sliding wedge as far as possible and to arrange the installation method of the fixed seat according to the actual situation in special cases; according to the fixed angle of the fixed seat of the punch, the approximate position of the sliding wedge in the plane of the die holder is determined.

When designing a standard inclined wedge die, as the stroke of the inclined wedge is already fixed, the following matters are to be considered.

  Ordinarily inclined wedge.

      As the working part is fixed on the lower die, it should be considered that the parts can be fed smoothly; its stroke should be ensured that it is not less than the width of the edge of the flange + the distance of the flange bevelled wedge trimming or punching or flanging + 20~30mm (note: 30mm in case of automated stamping, it should be 50mm in case of manual operation)

     Lift bevelled wedge slider stroke.

     Distance from the flange to the trimmed punched or turned edge of the bevelled wedge + 20mm;

Lifting the bevelled wedge requires consideration of whether the functional components (punch, side trimmer block, flanging block) mounted on the slider affect the assembly and disassembly of the press core; and whether there is sufficient space for grinding between the bevelled wedge and the press core.

Handling of scrap

  1. the scrap through the hole is as large as possible to open.
  2. sometimes, to prevent the waste from blocking, the waste of the side punching holes needs to increase the top material device. 
  3. castings to design the waste slide overhole to fully consider the width of the maximum size of the waste if rotation occurs.
  4. if the strap is too long, consider increasing the scrap cutter to achieve a smooth slide out of the scrap and increase the mould’s strength.
  5. use flexible ejector pins for convex (concave) moulds in the following cases.

        5.1. to make the scrap slide out piece by piece

        5.2. to control the state of the scrap as it falls.

  1. If there is a bounce in the scrap.

        6.1. the knife entry should be large.

        6.2. the need to install a scrap ejector.

  1. Additional scrap guides are required in the following cases.

        7.1. if there is no space on the waste exclusion side, it must be converted to fall vertically at right angles, with a minimum vertical aperture of twice the diameter of the punch.

        7.2. If the hole is punched on both sides simultaneously, it is necessary to increase the dividing pin.

Classification of the standard diagonal wedge die presses

 The pressure material device to the positioning of the parts, deformation to prevent the role, according to the starting shape, the number of action directions can be divided into three types.

1.1 Upper compression material core

The advantages are: the compression force is relatively large, so you do not have to worry about the deformation of parts; close to the vertical wall and near the end of the sidewall, with the upper compression core separation.

1.2 Slanting wedge side compression cores

 1.3 Shared use of side and front compression material

 Insufficient compression of the side press material.

 Unstable parts.

 Positive press material must be pressed 10 mm ahead of the side press material for the part.

Positioning of the diagonal wedge and protection against lateral forces

bevelled wedges have two types of pin positioning and key positioning.

 A thicker side trimming, flanging, and material thickness are needed to prevent lateral force.

Measures and forms of protection against lateral forces.

 Additional guiding devices.

The requirements for guiding bevelled dies are relatively high, especially with side punching and side trimming, as the gap between trimming and punching is very small, so a guide pillar generally guides such dies with a box heel.

A guide plate generally guides the press core, if there are special requirements, a guide column can be added (according to the customer’s specific requirements).

A tapered positioner can also be designed between the press core and the lower die to improve the guiding accuracy of the press.

The stroke of the nip must be greater than the length of the punch entering the nip. Otherwise, it will cause the punch to break.

Looking for a supplier for your stamping project?

V1 offers you a one-stop solution