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An increased use of lasers that can cut almost any type of material, along with increasingly complex parts that require greater accuracy, demand a user-friendly interface that makes bending complex parts easy, as well as a powerful CNC controller to assist the operator in calculating the blank size and bending sequence.

In addition to simplifying the bending process, advanced press brake controls help minimize machine setup. Set-up time continues to increase because of reduced lot sizes and newer manufacturing methods that minimize levels of raw material inventory and work-in-process. Setup time also impacts the flow of components for downstream operations such as welding, painting and assembly.

Today's controls develop the part program with limited operator input, as well as complete and automatic positioning of ram, bed crowning and backgauge axis for each bend, thus reducing setup time. On-line text files that travel with the program aid in directing the operator for tooling set-up, initial part positioning, and other specific instructions.

Even the simplest of tasks are enhanced. For instance, "tool filters" are used to remove from the menu the forming tools that cannot be used for the current part. The operator or programmer can only choose from a "pre-selected" list of tools for that thickness of material.

The current market demand is for shorter lead times and fewer quantities. Processes that were "hard-tooled" are no longer practical. Radius forming, for example, generally was done with a matched radius tools. The cost of the tool and the additional setup time was amortized over the entire batch.

Today, fabricators use flexible means such as "step or bump forming" to achieve the required radius. The programmer simply enters the angle, radius and resolution and the control calculates the angles and lengths of each form. Standard tooling is used, which can save thousands of dollars and weeks of lead-time.

As more complex parts are processed, machine setups become more complex too. It is not unusual to have three or four different sets of tooling in one machine at the same time. The locations of the tools down the length of the bed and ram is critical. Ram tilt, bed crowning and part interference man date exact locations. Some machine controllers have graphical display along with dimensions to aid the machine operator in correct tool placement. Advanced systems even have the means to project laser lines as a pointer to show the operator where the tools are positioned down the length of the ram and bed.

Because of machine and tooling deflection coupled with part thickness and hardness variations, it is typical for the machine operator to be required to apply corrections to the process. In the past, the operator would measure the part errors and manually assess and apply offsets. Most modern press brake rams are tilted in ten thousands of an inch increment. Some systems may use a percentage value to drive the bed crowning device. Because of the advanced mathematics required to convert angular errors to inches and even to percents, the operator would simply make an educated guess and make a tryout part.

Today's press brakes feature powerful controllers that will make these corrections. Some can even assess the corrections based on the location of the part down the length of the machine. The operator simply enters the angles of the part at the left, center and right. The controller recalculates a new tilting, crowning, spring back correction and automatically applies them to the program. Some advanced systems have automatic angle measuring devices, which completely automate this process.

Artificial intelligence coupled with a database is one method to produce an exact 3D-unfolded blank.

Some controls are able to create and store interactive databases for bend allowance. The user-generated data, created by actual bending results, are searched and applied each time a new part program is generated. This automatic optimization of the part program eliminates trial bending, and reduces the time required to produce a quality part.

The database resident in the control serves the same function as an experienced operator. Without this powerful feature, machine operators would need to learn the errors and imperfections in bending metal and would compensate for them. Today, these powerful databases identify errors and apply them to a new program, serving as an artificial intelligence built into the machine.

A broader array of features further simplifies the bending process. For instance, improvements in import utilities allow users to easily import 3D CAD drawings. Once imported, the software applies the technology from the resident database to automatically apply or calculate factors such as tools to be used, length of tools, etc. The information is calculated by the model and the technology is then applied to every bend automatically.