Maximum bending freedom for maximum quality

High cost pressure is often the driving force behind innovation: a few years ago, the BL 41 from WAFIOS made its mark. Now, the wire and tube processing experts present a flexible and economical development for lines up to 6 meters in length in the form of the BL 10 CNC multiple-head tube bending machine.

With extremely narrow grippers and short straight center sections, the WAFIOS BL 10 provides unique degrees of freedom for combined draw and roll bending with the narrowest contours. The modular concept with parallel work flows, rapid part transfer, minimized non-productive times, and automated optimization of the bending process reduces costs and increases productivity by up to 60%!

This development was motivated by the question of whether there was further scope for optimization with regard to an innovative and efficient tube bending concept. WAFIOS has now demonstrated that this is indeed possible. With the introduction of the BL 41 double-head tube bending machine in 2008, the Reutlingen-based company virtually turned the principle of bending thin tubes on its head.

Since then, the WAFIOS development department has constantly worked to bring together new findings, techniques, and customer requirements. With the modular BL 10 CNC multiple-head tube bending machine, the company has created a bending machine that is even more powerful, user-friendly, and economical than its predecessor.

The new WAFIOS BL 10 is certainly an attractive eye-catcher. The highly mobile bending heads, gripper tongs, and transfer grippers reach upward and seem to be waiting to clamp the extremely long and thin line blanks between their jaws, in order to produce perfectly shaped components for cars, machines, or machinery systems.

Due to the high cost pressure, today's customers require flexible systems which can process the largest possible range of lines with different dimensions, without complex tool changes and parameterization. The BL 10 only requires a very short amount of time to manufacture components with complicated three-dimensional geometries and more than 50 bends in line with the customer's requirements.

The machinery system is characterized by its simple parts supply, the highest quality of individual bends, high output, and a fast, predictable return on investment.

The BL 10 CNC multiple-head tube bending machine is intended for the automated processing of brake and supply lines with a length of up to 6,000 mm and diameters of 4-10 mm. Depending on the scope and requirements, the modular system can be fitted with up to three bending stations and two bending heads in each case.
At the Reutlingen plant, the BL 10-6 demonstration system with 6 bending heads and 42 CNC axes impressively illustrates how a large number of different bending jobs are efficiently distributed over three stations.

"With the help of several test series, we were able to demonstrate that complex bending processes can be produced in a more economical manner by distributing the tasks to several stations and bending heads. The cycle time is shorter, the output increases, and the cost per workpiece decreases despite the higher investment costs," says Bernd Eppler from WAFIOS.

Each bending module has 6 CNC axes. Thanks to a carriage and telescopic arm, the bending heads can be moved freely over the entire station. WAFIOS has developed an outstanding 3-axis bending head that can be positioned freely. The maximum bending space around the tool and its minimal interfering contours enable a wide variety of right/left roll and rotary-draw bending forms, with bending angles of up to 180 including the spring-back effect.

In addition, each bending tool can be equipped with several planes for processing various radii in the case of changing tube diameters as well as protective hoses. The gripper tongs positioned directly in front of the bending head provide support and line stabilization. The bending tools that are directly driven by servomotors guarantee maximum precision and repeat accuracy. Thanks to a backlash-free quick-release function, the wear-free tool supports are loosened in a few simple steps and the tools can be exchanged in the shortest possible time. This results in short changeover times and downtimes, as well as low tool and spare parts costs.

The unique loading and separation concept is implemented right at the start of the process. Bernd Eppler: "The operator simply places a stack of tubes onto the loading table and separates them with a flat hand. The guide rails and special mounting plates help to ensure that even thin and unstable tubes are quickly aligned in the feeder magazine."

Alternatively, an automated RVS magazine can separate long tubes without operator intervention. If required, the material supply can be coupled with various pieces of measuring and testing equipment for quality assurance purposes. A sensory measuring system determines the length of a tube and evenly distributes tube tolerances across the bending geometry.

At the end of the tubes, an easily integrable camera system monitors the size, correct fit, and color of the union nuts. This ensures that the system only bends parts that do not have any defects and minimizes machinery system standstills. Even end caps can be mounted easily thanks to the transport system.

The actual bending process begins when the tube is picked up and transferred through the transfer gripper and the first two bending modules. The clamping jaws hold the workpiece in a central position throughout the entire processing phase, until it is transferred to the next station or stored at the end of the process.

In the processing position, the two bending heads grip the tube which is supported by the gripper tongs. The bending process begins based on an efficiently coordinated step-by-step sequence defined by the computer. The bending heads are repositioned over and over again, and work their way down the line - bend by bend.

"This demonstrates the advantages of the WAFIOS bending heads with their free positioning: The rapid change from rotary-draw to roll bending, bending different radii and diameters with just one tool, as well as the extremely short straight center section (<90 mm), which symmetrically divides the work of the bending heads," emphasizes Bernd Eppler.

Once the first set of tasks has been completed, the transfer gripper transfers the partially processed workpiece to the second station, where bending heads 3 and 4 continue the bending process. Finally, all bending heads work on the respective bending process continuously and in parallel at all three stations. The bent ends vibrate without getting in each other's way.

The pre-simulation of the upcoming task with collision monitoring and automatic time-optimized distribution of the individual bends to the bending heads ensures an optimized process sequence.

As an option, the bending process can be optimized electronically with the iQsmartbend tool developed by WAFIOS. When bending long wire and tube parts, the process can result in major vibrations. In order to achieve the required quality, each individual process step must be slowed down and adjusted manually. This requires individual expertise, takes time, and costs money.

iQsmartbend reduces the vibrations via a computational optimization algorithm. This algorithm determines the optimum physical motion profile of the drives for each part. Using a secure online interface, WAFIOS provides its customers with this automatic optimization within just a few minutes upon request.

"With iQsmartbend, you will not only increase your output by up to 60%, but you will also increase the quality of the parts by avoiding unwanted deviations," emphasizes Bernd Eppler. As it is no longer necessary to carry out the complex relevant acceleration and speed parameter settings for each process step, commissioning and program changes can be completed very quickly as well.

Once the last bending step has been carried out, the transfer gripper places the three-dimensional part, which has been bent exactly according to the customer's requirements, onto the discharge slide. The finished lines are subsequently packaged and prepared for shipping, or delivered directly to the assembly line.

The modern control system guarantees reliable processes and the intuitive operating concept ensures that the machinery system is easy to handle. The convenient sequence programming is carried out with WAFIOS WPS 3.2 Easyway.

Our above-average production capacity, availability, expertise, and extensive experience in tube bending guarantee that your investment is in safe hands. In the future, we are planning to introduce a reinforced variant, "BL 12", to process lines up to 12 mm in diameter.

Editing: Frank Lindner