How To Choose Pressbrake For Metal Bending

You don’t know how to choose and set up a press brake? The most important factors to be kept into consideration are:

Length
Tonnage
Daylight and stroke
Throat
Tool clamping and tool adapters
Back gauge
Compensation systems
Energy saving systems
Front support arms and sheet followers
Angle control systems
Optionals and accessories

Choosing a press brake won’t be easy, but with this 4-part tutorial you will be able to pick the right press brake for your job. In this first part, we will focus on how to choose length, tonnage, daylight, stroke, throat, tool clamping, and tool adapters.

1 — Sheet metal bending Length

It depends on the maximum length of the workpiece to be processed. If you bend by stations, i.e. with multiple working stations on a single press brake, you will need to add up the length of the individual stations. For example, take a 700×1800 mm panel. You can bend all the short sides first, retool the machine, and then bend all the long sides. This way it would take a 2000-mm long press brake, but efficiency would be pretty low. On the other hand, you could choose a 3000-mm machine equipped with two working stations, one for the long side and one for the short side. So you don’t have to take up work again and processing times are reduced.

2 — Tonnage for how many thickness of sheet metal bending applications

It’s the bending capacity of a press brake. 5 main factors come into play:

material: softer materials like aluminum require less tonnage with respect to stainless steel or high-strength steel
thickness
length
die opening: smaller Vees result in higher tonnages
process: air bending requires less force with respect to coining or hemming.

Don’t forget you should always oversize the press brake by 20/30% compared to the theoretical data, to be able to manage the variability in the characteristics of the material and for not working to the limit of the capacity of the machine.

Furthermore, if the load is concentrated in a very small area (for example with thick but short pieces), it is better to choose a bigger machine size to avoid deforming the ram.

3 – Working area: daylight, stroke, and throat, depends on Max sheet metal bending profiles

What do we mean by daylight and stroke a press brake? Together with throat, they are part of the dimensioning of the working area.

The daylight is the front opening of the press brake. Increased daylight version is equipped with tool holders and allows to easily bend boxes without using special tall punches.

Versions with extended stroke allow for easier extraction of formed pieces.

Throat is the C-shaped aperture in the side frames. It varies according to total dimensions of the press brake. An increased throat is useful to extract pieces from the sides or for machines in tandem.

4 — Tool clamping and adapters

Different clamping systems allow to change and rearrange tools. The more fragmented your production lots, the more important are shorter setup times. Remember that a press brake is paying for itself only when it’s bending parts!

5 — Pressbrake Back gauge, 2 axis , 4 axis and 6 axis cnc controlled auto pressbrake back gauges

The basics: X-R axes, 2 axis pressbrake back gauge

A press brake is equipped with a backgauge, a motorized structure to which backstops (also called “fingers”) are attached. By resting the metal sheet to the fingers, we determine the bending line. Movement of the backgauge along the machine depth (i.e. perpendicular to the ram) is called X axis. Vertical movement is called R axis, and is useful when we have profiles with multiple bends.

Working with bending stations or different lengths: Z1-Z2 axes, 4 axis press brake back gauge

Back gauge fingers are at least 2 in order to keep the piece in position. Their repositioning is usually manual, but can be motorized to facilitate working with bending statons or with pieces of different lengths. Movement is along the Z axis (parallel to the bending line), hence each of the backstops is named Z1, Z2, etc.

6-Hydraulic Crowning or Motorized mechanical crowing table

It depends on the bending thickness and length, more details can get professional suggestion from AHYW China Yawei metal guillotine and pressbrakes manufactures

7 – Energy efficiency, Hybrid CNC Pressbrakes

CNC Pressbrakes included Hydraulic cnc pressbrake, Electrical CNC Pressbrake and Hybrid CNC Pressbrakes.

More detailsa nd advantange of Hybrid Pressbrake China Yawei made, you can refer to the following links:

AHYW China Yawei 4mtr CNC Hybrid Pressbrakes with Hoerbiger Eprax Hybrid system

https://www.ahycncs.net/hydraulic-press-brakes/cnc-hydraulic-press-brakes/hybrid-press-brakes-4m-ahyw-yawei-china.html

CNC Hybrid Press Brake machine is the latest high technology generation of Synchro press brake design, thanks to German Hoerbiger ePrAX Electro Hydraulic Hybrid system design.

Eco-friendly, 65% energy saving, Accurate,Fast, Quiet, Efficient, Durable

This systems is the consistent further development of servo driven press brake systems

from HOERBIGER. Hybrid press brake machine using one variable speed servo

motor pump to drive&control real position and bending pressure in time