In the world of laser cutting systems, automation plays an increasingly important role. The cutting speeds achieved today have shifted the attention of many companies to the loading and unloading operations, which often risk becoming dangerous bottlenecks. But navigating among the various solutions available on the market, and choosing the one most suitable for your own specific needs, is a matter which is anything but trivial. We asked Pierandrea Bello, Salvagnini Product Manager for laser technologies, to answer some of our questions.
Pierandrea, it is now abundantly clear that automation is the keystone for optimizing production. Salvagnini’s laser automation range has always been very extensive and modular, allowing each system to be configured differently to suit different production needs. In your experience, which solutions are most popular with the market?
Laser automation is certainly one of the most interesting trends we have seen develop over the last few years. And as you quite rightly highlighted, automation has a positive impact not only on the efficiency of the individual machining steps, but also on that of the entire production process: this is what, in our vision, makes it absolutely decisive in the current industrial scenario. I’ll give you some numbers to put it into perspective. We have used LINKS, our IoT solution that continuously monitors the data from systems connected all around the world, to assess the efficiency of different configurations, analyzing the many variables that come into play, such as the type and weight of the sheet metal used and the material handling and waiting times. The results of this study are remarkable: while stand-alone solutions have an average efficiency of around 60%, automated systems have much higher efficiency values, reaching 80% or even 90%, if we take our LTWS store-tower into consideration. This study also allows us to understand why, over the last few years, the LTWS store-tower has been the most widely requested automation in combination with our L3 and L5 models.
Over the last three years, 50% of our customers who have invested in automated loading/unloading have chosen LTWS to complete the configuration of their system. LTWS, in configurations from 6 to 38 trays, with its ultra-rapid cycles and high autonomy, is an extremely compact high-end solution. It is available in compact, single- or double-tower versions, with wooden pallets, without wooden pallets, or mixed. In the single- or double-tower versions, the loading and unloading devices are independent, increasing process efficiency even in extremely rapid cutting programs, while the compact version offers smaller dimensions and shorter cycle times, which can be further reduced with an extra bay. Autonomy is guaranteed by the availability of multiple materials, and by the STORE software, which identifies the empty loading trays as new stations on which to stack the processed material.
In short, an enormous variety of customization possibilities are offered. But how to identify the solution best suited to a specific production context?
We do realize that the choices are numerous: for this reason, an in-depth feasibility study is always the starting point for our discussions with customers. Salvagnini’s specialists work alongside them to define the most suitable configuration for their production needs, evaluating a number of variables including the field of application, the production strategy and the production mix. In the case of an LTWS store-tower, there are nevertheless some constants to take into consideration: the maximum possible dimensions, the required autonomy and operational flexibility, whether or not it is necessary to incorporate an automatic sorting device, the need to access the pallet changer, and the investment which will be required. Are you looking for a compact system? Do you have a limited budget? In this case, an LTWS Compact is very probably the solution for you. Do you have restrictions in terms of space, but need a good level of autonomy? Do you want to maintain good operational flexibility or incorporate an automatic sorting device? In this case, the best choice will probably be the LTWS. Do you have no limitations in terms of the size of the store-tower, but require the highest possible autonomy? Well then, a double-tower LTWS will be your ideal choice.
Pierandrea, at this point I’d like to ask you to talk a little more about unloading the cut material and skeletons, and also to clarify another concept which has come up more than once in our conversation: automatic sorting devices.
It might seem obvious, but I think it’s worth saying again: without an automatic sorting device, our LTWS will return the sheet metal to the store-tower, and the operatives will then have to separate and stack the parts. In this kind of situation our software will always offer three different strategies for managing unloading: fill mode requires an unloading tray to reach its maximum capacity before being changed, while material mode involves the unloading tray being replaced on the basis of the material to be unloaded and finally, order mode involves all the sheets in the same production order being unloaded onto the same unloading trays. The operator can choose and modify the unloading strategy independently as required. On the other hand, the LTWS store-tower can achieve even higher performance if equipped with a sorting device. Salvagnini offers the TN manual sorting device, which assists operatives in separating the cut parts from the skeleton, proceeding in parallel with the cutting job. We also offer the MCU automatic sorting device, which is a solution for easily stacking parts with different geometries, sizes and weights. In addition to the standard sorting strategy, MCU can work in multi-gripping mode, picking up several parts in sequence with the same gripping device or in double-picking mode, reducing the time needed to pick up the parts. The MCU has very few limits: it can pick up thicknesses of between 0.5 and 12 mm and weights of up to 65 kg for each manipulator or 130 kg when the two gripping devices work together. The flexibility and extreme mobility of the manipulators, which can rotate a full 360°, removes all geometric constraints: the gripping devices can pick up any part, whatever its maximum size or shape. The minimum dimensions, on the other hand, are 100×200 mm. But to overcome the dimensional limitation when unloading parts below the official threshold and to prevent automatic sorting from reducing the sheet metal yield, Salvagnini now offers the new smart cluster function. Smart cluster is used to micro-joint parts together quickly and easily, without using a cutting frame and without making programming more complicated in the office. At the same time, smart cluster is yet another solution for reducing total unloading times. The MCU is managed by the Salvagnini CM software, which automatically defines the grips, automatically generates the unloading sequences and positions the stacks of parts in the unloading areas. The interface is easy to use, allowing manual interaction and fine tuning. CM can be used both in the office and on board the machine. The MCU integrates perfectly with the whole range of Salvagnini automations, making the operators’ work easier, drastically reducing waiting times between the end of the cutting and the start of the next processing. It can make single parts immediately available for downstream processing in urgent cases, or physically integrate the laser with downline panel benders, press brakes or robotized bending cells.
Pierandrea, from what you’re telling us, choosing an automatic sorting device is a real paradigm shift which can lead to doubts and uncertainties. Is the investment in this kind of device justified? What is the return on investment?
Those are good questions. As regards the return on investment, the MCU can reduce the labor required for part sorting by over 80%: this is a significant parameter. So clearly, even if we consider only the reduction in operating costs, the return on investment time is really short. But the MCU also guarantees significant technical advantages: the high flexibility in terms of the materials, thicknesses and sizes that can be unloaded without having to reconfigure the gripping devices is a fundamental aspect for managing highly variable productions. With multi-gripping, double picking, and smart cluster, sorting times are very low and masked for most nests. The rapid, easy-to-use software can automatically manage the majority of activities. The MCU is extremely reliable, while the overall dimensions of the unloading areas required to guarantee operating autonomy are generally less than those required for manual sorting. So there are really many good reasons for investing in an automatic sorting solution. The clearest benefits derive directly from the elimination of manual sorting activities: a reduction in operating costs and in problems relating to the availability of labour and the risk of accidents, as well as the reduction in waste linked to handling damage, which may be frequent during separation. But equally important is the possibility to plan the sorting times very precisely, as the automatic device makes these constant and repeatable, as well as the possibility to separate the material produced during any unmanned shifts. But there are three more advantages to automatic sorting: the first is that it optimizes the production flow as it makes the material available sooner for sending to the downline workstations, the second is that it simplifies part traceability by grouping parts by order, kit or subsequent workstation, depending on the production strategy, the third is that it increases the overall flexibility of the system.
For more information, please contact PIM Machine Tools – 011 022 4648
