A press brake is a highly valuable tool for bending metal. But there’s no such thing as the perfect press brake. Only the one that’s perfect for you, in order for the press brake to deliver real value to your operations, you’ll need to ensure that you have the right one for your needs.
Before the order, take a moment to read these important notes about what you should first consider. Such as you need to know about press brakes, including the different models available, how to figure out which one is right for you, and some other key considerations you’ll need to keep in mind, to make sure you know exactly what you need out of the machine you’re looking for. It will make buying a press brake much easier.
The difference between press brakes and other sheet metal manufacturing machinery
Let’s start of with a brief description of what a press brake is versus other forms of sheet metal manufacturing machinery.
A press brake is a mechanical processing tool that is mainly used for sheet metal bending and forming. A press brake is typically narrow and long so that large pieces of sheet metal can be bent by it.
The molds of press brakes have different shapes and the bending angles can be set in advance. Hence, different shapes and angles of metal sheets can be produced massively.
The machine controls the distance between the upper and lowers toolsets through manual or CNC controls bringing the tool sets, with the material close enough to bend the material to the desired shape plus accounting for a little material spring back, the metal may be bent several times by a press brake until the desired form has been achieved.
The most common applications for a press brake are fabricated metal part forming including electrical boxes, enclosures, signs, and many other sheet metal fabricated components.
Common Types of Press Brakes
There are 2 main types of press brakes and several ways they are driven. The two main types are:
- Down Acting: The vast majority of machines are of the down acting design. This refers to the upper tool set being driven up/down.
- Up Acting: Just the opposite of the above, the up acting brake moves the bed uHYp towards a fixed and static punch.
The ways these press brakes can be driven is either Mechanically through a flywheel/clutch design, Hydraulically, or Electronically through belts or balls crews.
NC vs CNC Press Brake: How to choose?
Quantities of parts needed as CNC controls and functions can greatly improve repetitive jobs. Operator Skill Level needs to be assessed as the less skilled the operator the MORE you should be relying on a CNC control to calculate the bends and sequences of bends.
And when it comes to the matter of press brakes, to go with an NC or CNC model is a very good question, asked perhaps by those looking to expand and grow their business, or particularly by those whose press brake may be approaching the end of its serviceable lifespan, then there is a very good possibility that it will be a trusty NC (numerically controlled) press brake.
NC press brakes have, for many years played a vital role in our industry and continue to be in demand today. But more and more now, CNC (Computer Numeric Control) press brakes are enjoying the lion’s share of the market, and there are several, very good reasons for that.
NC press brakes can normally control only the X and Y axes, but for CNC press brakes, it can control at least, 3+1 axes. Other options can be 4+1 axis, 5+1 axis, 6+1 axis, 7+1 axis, 8+1 axis and the like. These can work to bend more complex products.
CNC Press Brakes
- Date or graph programming, easy program, modification and editing.
- Several CNC axes for optional.
- Stable synchronous performance, better flexibility.
- CNC controller can detect and correct ram inclination
NC Press Brake
- Program cylinder strock and back gauge movement.
- Only X axis.
- Torsion rod ensure the ram synchronization mechanically.
Reliability and consistency
CNC press brakes that are much more automated and that means a more complex job can be undertaken by a lot more people, a much wider range of people can operate the machine any time.
An automated option
Computer numeric control (CNC) gives you what is basically a tailor-made PC built into your press brake. That is a big deal for several reasons; firstly it gives you precision, not just the sort of precision attained by careful handling and an experienced eye needed for your NC press, but complete precision with up to five times more accuracy than conventional NC press brakes. CNC press brakes offer speed too, with a safe and fast backgauge and servo drive taking care of repeat-ability, no matter how complex the bends uploaded to the on-board PC software.
A machine that anyone can use
Once the program on a CNC press brake has been set up by a skilled operator, and it only needs to be done once then the CNC pressbrake is a machine that anyone can use with the same high quality and accurate results.
7 Things You Must Determine Before Purchasing a Press Brake
Press Brake Width Needed
What is the maximum material width you will need to bend and what is the maximum flanges Material in a press brakeyou will be bending. These two questions are critical in determining the overall bending length you will need on a press brake. If your bending up to 10” of material but your flange is 12” then you likely need to move up to a 12’ wide bed so you can pass 10’ of material completely through the press brake.
Control and Gaging System
If your bending simple 90°’s your perfectly suited for a simple NC 2-Axis machine (X-Axis only on gauge). However, if your bending complex electronic enclosures, internal support brackets etc that have complex and angled bends your likely suited for a much more sophisticated gaging system and control on your machine. Backgauges can be equipped from 1-6 axes and more with additional gauge fingers etc. Although the most popular setup is a simple 3-Axis setup (actually 4 with Y1, Y2, X & R), your needs may require or benefit from adding additional axis to the backgauge and a more powerful and graphical controller. All these extra axis’ add a level of complexity to the press brake BUT they also add a great deal of maneuverability and capability too.
Tools and Crowning device
Part accuracy on a press brake is a combination of handling many factors in the material you’re working with including material hardness, yield strength and springback. How the press brake is outfitted determines how it handles a variety of material deviations AND the final part accuracy. Typically the thinner the materials you’re working with the more pronounced the forming defects will be and this you will have a need to compensate for them. Your first approach should be to use good precision ground tooling that repeats each and every time you load it in the machine.
Secondly, you can look at adding a manual or CNC Crowning device which replaces the need to shim the dieset. Lastly you can investigate many angle measuring devices from gauges in the fingers (Trumpf) to Laser Angle Measuring devices that measure the resulting bend angle in real time but be careful when considering these add-on accuracy devices as they are known to work great in the demo center and fail miserably on the shop floor.
Robotics or other Automation
Whether your a small job shop, or a high production manufacturer, the number of parts required per day can determine not only how the press brake is equipped but how its loaded as well. When buying a press brake you need to know how quickly you can produce quality parts by hand and/or if automation is needed.
Clamping and Precision Tooling
If you run the same parts (or the same toolset) day in and out then you would likely not benefit from some of the enhanced tool handling features available on today’s press brakes. However if you are changing tooling out 3-5X a day or more on your press brake, or plan too then you definitely need to consider the productivity enhancements that will be achieved with features like Hydraulic Ram Clamping and Hydraulic Die Clamping. These features along with Precision Ground Segmented tooling can reduce your tooling changeout time from 10-15 minutes to just a few seconds. AND with the right setup on your press brake, the tool is automatically seated too eliminating the need to run the tool into the die to “seat” it.
Lastly when your buying a press brake you need to consider the skill level you have available to work with. Typically you will find that the more powerful the control, the less skilled the operator needs to be. Yes, that is correct, the more powerful the control the less skill you need from your operator as the control does much more “thinking” (calculations) for you. Controls today calculate for bend allowance, set pinch points, gage points and bend sequences all automatically taking a ton of setup time off the operator or better yet, your lead fabricator. The more control you add to the press brake the easier it is to set up and make good parts the first time and every time.