AL-Cut AG’s two Managing Directors. His company supplies customers throughout Switzerland. Recently, he got this phone call: A customer needs metal struts for staircases: 800 parts, complex geometry, made of 10mm (3/8”) steel. “Can you manage that by tomorrow? I will send you the details by email.” An urgent job. Räber remains relaxed: “We will prepare an offer.”
The nine-man shop produces small runs and prototypes. Until now, jobs exceeding 500 parts tended to be the exception. For a part run this large, it is difficult for Al-Cut to prevail in the face of the hard price competition.
But for several months, AL-Cut has been using the ByOptimizer. The online service from Bystronic optimizes laser cutting by breaking new ground in the process of generating cutting plans. ByOptimizer is based on a newly developed cluster technology, which aligns the parts that are to be cut so closely on the metal sheet that the raw material gaps are reduced as much as possible. Placing the parts so closely together shortens the laser’s cutting paths. In addition to saving raw material, this also enables reduced cutting times.
Thomas Seeholzer and Tony Raber perform a final check of the cutting processes on the laser cutting system’s screen.
Reducing costs by mouse click
Usually, his customers obtain quotes from several suppliers. “Simply using a fast laser is only half the battle,” Räber says. Although it enables fast cutting speeds, the preceding process step is decisive: the optimal grouping of the parts on the metal sheet.
Just a few minutes after the call, the email with the customer’s order data arrives at AL-Cut. Now it’s up to Thomas Seeholzer. He is AL-Cut’s laser cutting expert. Seeholzer enters the data from the email attachment into the basic Bystronic BySoft 7 software. The screen displays an elongated part that looks rather like a coat hanger. “I am curious to see how the ByOptimizer will place that on the sheet metal,” Seeholzer says. The challenge is to group a total of 800 of these polygonal parts on several sheets so that as little residual material as possible is wasted. He performs another check of the part’s CAD drawing. Then he sends the file to the ByOptimizer for the next processing step. The online service is integrated directly into BySoft 7. This simplifies data processing, because the user remains within the BySoft 7 software interface during all the process steps.
Seeholzer clicks on the “upload” button. Now everything runs automatically. The ByOptimizer sends the job data to the server center. Here, an algorithm is applied to the data and generates a cutting plan. Thereby, the software draws on extensive know-how. A database incorporating more than 300 parameters provides comprehensive information about ideal cutting processes and the varying behavior of the material to be cut. Based on this information, the ByOptimizer creates the ideal cutting process for the 800-part potential order.
It’s as though 300 experts were simultaneously working to create the best possible cutting plan for AL-Cut. All the relevant aspects are taken into account: Are the parts that are to be cut placed ideally on the metal sheet? Are the laser’s cutting paths and feed rates programmed in a manner that prevents risks? Can the undesired heat, which the laser produces within the cutting material, be reduced? How many piercings are necessary per contour? Must micro joints be included in the cutting plan, in order to attach the cut parts to the residual sheet?
After just 50 minutes, Seeholzer receives the finished cutting plan. He looks at the grouping of the parts on the screen and is impressed: “There really is hardly any waste material left on the residual sheet,” he says. On the virtual cutting plan, the parts are placed so closely together that many common cutting edges are created. Only a few gaps remain. This type of grouping has two benefits: It saves space on the metal sheet and reduces the cutting time; in some cases by 50 percent. With common contours, one cut is sufficient where two would otherwise be necessary.
Preparing the offer for the customer, the ByOptimizer offers a major advantage, Seeholzer explains. With the aid of the online service, one can calculate using precise data, and thus prepare a precise offer in a relatively short period of time. Even before AL-Cut actually purchases the optimized cutting plan, the company can simulate the ByOptimizer’s proposed cutting plan, approve it, and use it to prepare an offer for the customer. The ByOptimizer’s virtual cutting plan provides the company with all the important information in advance: the amount of material required, the cutting lengths, and the processing time. AL-Cut then makes a binding order for the cutting plan, after the customer confirms the job.
Not much is left: Thomas Seeholzer shows a remaining residual skeleton.
By hand? Impossible
What would it take to manually create a cutting plan that is comparable to one generated by the ByOptimizer? Seeholzer laughs: “A great deal of know-how and patience.” The programmer has to know the precise behavior of the sheet metal when the laser cuts it. The material behavior changes depending on the cutting speed and the power of the laser. The heat that the laser beam generates within sheet metal causes stresses in the material. This in turn can cause problems, particularly when cutting closely grouped parts, he explains.
The ByOptimizer takes account of all these details, which even experienced users cannot keep in mind all the time. Particularly not when things are hectic. “Like today,” Seeholzer says. “The inquiry for a job comes in and in order to save time, I do not want to spend a lot of time creating the cutting plan.” The ByOptimizer’s algorithm is more precise than a human, particularly in the stressful day-to-day business environment of a job shop.
AL-Cut receives the order. The customer has just confirmed the offer. The delivery period is 24 hours. Now Seeholzer books the cutting plan in the ByOptimizer and sends it directly to the CO2 laser cutting system. AL-Cut uses a six kilowatt Bystar from Bystronic. One can tell that the machine is put to hard use here. The “Bystronic” logo on the upper edge of the safety door is worn away. Seeholzer and Räber perform a final check of the cutting processes on the laser cutting system’s screen, then the machine starts to work: 800 parts on 11 metal sheets with a total cutting time of less than four hours.
After the laser’s initial cuts, Seeholzer checks the cut parts. He stops the laser, opens the Bystar’s safety door and removes two cut parts from the cutting grate. “Clean cutting edges. A good result,” the expert judges. In terms of quality, the use of the ByOptimizer at AL-Cut must achieve the same level as conventional cutting plan programming. The raw material savings and the shorter cutting times made possible by the online service only provide a competitive advantage for AL-Cut if the final results are first-class.
ByOptimizer places the parts that are to be cut so closely together on the metal sheet that the gaps are reduced to a minimum.
“Naturally, at first we had some concerns. We were skeptical,” Räber explains. In contrast to cutting plans that are created using the conventional procedure, using the ByOptimizer means relying on a completely new technology. But it soon became clear that the online service provides good results. And even more: It is stimulating business. For example, this 800-part order. With these, the ByOptimizer speeds up the entire workflow. Starting with the offer, through to the optimal grouping of the parts to be cut on the metal sheet, and error-free cutting on the laser cutting system.
After approximately four hours, the 800 parts are cut. Seeholzer has already neatly stacked the metal struts on pallets. Behind the Bystar, there are now eleven delicate residual skeletons. Thomas Seeholzer lifts up the one lying on top: “There is not much left here to go to scrap.” AL-Cut was able to save approximately 30% of the material on this job. Without the ByOptimizer there would be at least four additional residual sheets with a great deal more material left on them.
Prepaid plan enables a fast entry
Users receive access to the ByOptimizer using a prepaid plan. The options are an annual subscription with unlimited access, or a monthly subscription with a limited number of cutting hours. With the monthly subscription, the required cutting time per booked cutting plan is deducted from the account. In addition to a prepaid account, ByOptimizer users require a PC with Internet access, BySoft 7, and a laser cutting system from Bystronic.