1. Upper Tool Clamping
Every tool is clamped into a press brake differently depending on the press brake connection.
As previously stated, there are two different attachment categories:
Tools clamped directly into the upper beam
The tools are inserted into a slot and fixed directly into the upper beam of the bending press.
This tool type is called “axial”， as the punch tip is along the same axis that passes through the middle of the tang （see picture below）.
The punch is secured by a clamp on the front side of the upper beam either manually with screws or automatically with a pneumatic or hydraulic clamping system. The clamp length depends on the press brake type.
This type of tool has a high capacity and is therefore suitable for bending thick sheet metal.
Axial tools have the advantage that they can being mounted on either side, i.e. with their gooseneck towards the front or towards the back of the press brake.
The most well-known tools of this type are Wila, Trumpf, Beyeler, Gasparini, Colgar, LVD, Colly, Axial, American and Newton.
Tool clamping using intermediates and adapters
Punches are clamped by an intermediate which is held by a clamp screwed to the press brake upper beam. Intermediates are never removed unless an operator needs extra space to produce particular profiles.
Standard Promecam intermediates are 100mm high and 150mm long and are mounted at intervals of about 70 mm up to a total of 5 intermediates per meter.
Machines with the Promecam standard use wedges for manual crowning of the press brake.
With Promecam intermediates, punches can be mounted on either side in order to bend particular profiles or to prevent the operator from injuring his fingers between punch and die. On both sides, the punch works along the intermediate axis. Therefore it is possible to combine tools by mounting them on oppositesides as shown in the picture below.
To mount a punch on the back of an intermediate, the operator has to unscrew the clamp and mount it at the back. Alternatively, he can use faster clamping systems consisting of a front and a back clamp, which can clamp a punch on both sides.
If an operator has to mount tools with a tang that differs from that of the press brake, he can use adapters. They have the same tang as the press brake slot but their lower part allows for the clamping of tools for a different tang.
If an operator decides to mount an adapter, he must check that the daylight of his press brake is big enough.
If an operator mounts adapters or intermediates, he must check their capacity; for example the capacity of standard Promecam intermediates is 100T/m.
Adapters are increasingly used for old press brakes with old tang types to mount cheaper tools with different tangs, which are easily found on the market.
2. Lower Tool Clamping
As with upper tools, the clamping of lower toois depends on the standard used and on the features of the press brake.
Dies must be clamped properly to prevent them from being shifted or lifted by the sheet metal during the bending process.
Once dies have been clamped, the operator must check that the vee center is along the same axis as the punch tip.
If it is not, the operator must unscrew the clamps, lower the upper beam until the punch tip reaches the vee bottom, keep the upper beam in this position and then clamp the dies.
Promecam type dies are usually clamped by means of:
- Clamps fixed to the table by 2 screws, which clamp the dies to the press brake table.
- Die holders, a kind of track into which the dies are placed and secured by grubscrews. If the grubscrews are close enough to each other, sectioned dies can be clamped properly. Die holders are used, above all, for equipping older presses.
- Adapters, which can clamp dies with a different standard from that of the press brake or special dies.
- Fast clamping systems with hydraulic or pneumatic clamps that fix dies through the activation of a hydraulic or pneumatic pump.
Where dies with different standards are used, they can beclamped by other mechanical,pneumatic or hydraulic systems.
Wila and Beyeler type dies with 13mm bases are inserted into a groove in the press brake table and fixed mechanically with grubscrews or with hydraulic or pneumatic pistons.