Workpiece clamping technology
Always that one step more
Siba is not exactly a typical contract manufacturer. This is demonstrated by its strategic focus on machining and sheet metal processing. The range of technological decisions also stands out. In workpiece clamping, for example, the Dillenburg-based company is currently taking the step from automated palletizing to 6-sided machining with Gressel and the “R-C2” system.
When a new component is due to be milled at Siba, the process is almost always the same: “First we assess whether 3- or 5-axis machining is required, then the blank is designed and checked, and finally the clamping system is selected.” Center or 5-axis clamp? Pyramid or tombstones? Benjamin Herbert, Head of Machining Production, then switches to his PC to load the CAD data, view the drawing and check for collisions. Just recently, a new component for aircraft cabin interiors was passed through production in this way. A 5-axis part made of aluminum with a focus on the visible surfaces. Once the part had been programmed and simulated, it was placed on the machine in two set-ups with two different clamping devices.
The right clamping vise for every part
In principle, Siba now has the right clamping system for every part, most of which are produced the size of a fist. “This starts with 5-axis clamps from the ‘SC5X’ series and extends to machine vises in the ‘gripos’ design through to centric clamps from the ‘C2.0’ and ‘C3’ series,” reports Klaus Thut, distribution engineer at Gressel. “We also use ‘M1’ and ‘multigrip’ multiple clamps as well as various clamping tombstones.” This means that almost all of the workpiece clamping technology used in Dillenburg comes from Aadorf in Switzerland. Advice on new systems or components and their sale is provided by partner Ceratizit in the person of Lukas Faak: “If further technical support is required, this can also come directly from Gressel. At this point, we have usually already coordinated in detail.”
Consistency in the modular system
It’s easy to see why Siba has been working with Gressel technology for over a decade: Product diversity and variability, degree of innovation, consistency, availability, reliability, support. “We use a tried-and-tested system that is highly differentiated and highly compatible and that is consistently developed further,” emphasizes Benjamin Herbert. “No clamping system stands alone; it can always be combined and equipped with options.” In addition to this compatibility and consistency, he particularly appreciates the reliability with which he can use information on usage and its parameters. “The clamping systems can also be used with high precision even after many years.” The support is also evident in the provision of 3D data, which he needs for programming. “I simply download the data from the Gressel website,” explains the production manager. “Ceratizit in turn guarantees the availability of the systems, which are with us the next day on request.” Together with Gressel, Ceratizit also ensures the provision of new technologies such as R-C2 automation. With a 5-axis machining center expanded into a production cell, the system for unmanned 6-sided machining is currently being run in.
Two worlds united in one product
Siba is a pure contract manufacturer that – as a distinguishing feature – combines machining and sheet metal processing. The sheet metal and milled parts that the company produces with high precision, like the welded and assembled components, are often used in regional mechanical engineering, and more recently also in the aerospace industry. Other important markets are switch cabinet construction, supplemented by the food industry. “Most of our customers purchase both sheet metal and milled parts as well as assemblies and draw on precisely our strengths.” Sheet metal processing ranges from laser cutting, punching and edging to joining, surface treatment and final assembly. The customer receives the ready-to-install product in the same way as from machining. Before delivery, the products from both production lines pass through the QA department and documentation.
The next step is coming
Looking at the overarching production principles, Siba has invested heavily in digitalization and automation in recent years. In an ERP system, for example, “with which work preparation is now state-of-the-art, as is administration. In machining, Siba switched from crane loading to automated palletizing some time ago. The next step is now 6-sided automation with the R-C2. “With this investment, we want to increase throughput with the same number of employees. Alternatively, we had calculated the expansion via pallet technology and an increase in production space, employees and infrastructure. This would have been much more expensive for us.” Above all, Siba wanted the R-C2 to be a system that could work independently and complete many different parts at the touch of a button. “With unmanned machining, there are fewer influencing variables than with manned machining, which are also easier to control,” says Benjamin Herbert. “By eliminating human intervention such as reading the set-up plan or manual reclamping on OP20, we are less prone to errors with less effort. We can also make better use of unmanned hours at night. Conversely, this means that we increase throughput.”
The workpieces are fixed using 5-axis clamps “SC5X”, centric clamps “C2.0” and “C3”, machine vises “gripos”, multiple clamps “M1” and “multigrip” as well as clamping tombstones and pyramids.
Once again: availability, accuracy, reliability
The impact of the R-C2 system on the machining spectrum is demonstrated by a recent inquiry from a machine manufacturer that builds feeding systems for the automation industry. “He wanted to have 700 parts produced at short notice, but we were unable to map this,” emphasizes Benjamin Herbert. “The level of panel automation that we still had at that time was simply not enough. So we had to turn down the order.” The production manager then calculated the whole thing again – with the result: “The R-C2 system would have enabled us to process the order without any problems. It’s clear that a situation like this will happen again. But then we can accept the order.” In the meantime, the production manager is already planning consistently with the new system. Because one thing is also clear: “The market is demanding more and more speed from us. The price is even less important; availability, accuracy and reliability are crucial. We want to do justice to this.”
Largest possible configuration ordered
In terms of batch size, Siba is not ruling anything out – however, its hobbyhorse is 1 to 200. “When it comes to milling, we score points because we were already able to process batch sizes 1 and 2 quickly with pallets. The R-C2 system will make us even more efficient,” says Benjamin Herbert confidently. “We often produce cubic, easy-to-grip parts, 80% of which are made of aluminum and 20% of which are made of structural, tool and stainless steel.” With machining rates of often 80 or 90%, the quality requirements are very high. With this spectrum, Siba aimed for the most far-reaching configuration of the R-C2 system from the outset. “We didn’t want to limit ourselves, we wanted to reliably map batch sizes up to the three-digit range.” Even today, shortly after starting up the cell, it is clear that the R-C2 system, which grips and fixes components using a clamping system, can be configured and set up very quickly. “If a customer calls today because they need a milled part in 24 hours, that’s the exception, but we can do it.”
Flexibility is the be-all and end-all
In the Siba configuration, the R-C2 uses several drawer levels to handle the components. To ensure that as many different parts as possible can be fully processed in OP10 and OP20, Siba examined the multi-batch system in detail in advance: Can several individual parts be stored in one drawer and a larger batch in another? Where is the optimum? How far does the flexibility extend? At the same time, the configuration for gripping the parts was exhausted with 14 options. The flexibility, which is therefore paramount, extends to the machine, which offers 300 tool positions, among other things. “This allows us to keep the CAD programs available and react quickly with a standard range of tools.” The fact that Siba is also thinking one step ahead when it comes to tools is demonstrated by a “Tool-O-Mat” from Ceratizit, which acts as an output system to ensure tool availability.
One more step?
The R-C2 system has been further expanded so that it can also handle smaller pallets in addition to clamping systems. The automation specialist Promot, who set up the production cell, integrated an additional output point for this purpose, so that pallets can be set up freely configurable outside. Benjamin Herbert estimates that it will take a year to optimize the system, which is perfectly fine with him. “When a system like this is up and running, it doesn’t make much difference whether I operate one or more of them. The workflow is the same.” What does Benjamin Herbert mean by this? Siba’s current step could be the penultimate one: “Because now that the current project has been completed, we are already thinking about the next one. We’ve actually already ticked off the system. And are now thinking about what our parts will look like in two or three years’ time, i.e. how we need to position ourselves. The next step could therefore be a second or third RC-2 system.
Contacts
Gressel AG
Schützenstrasse 25
CH-8355 Aadorf
Telefon: +41 52 368 16 16
E-Mail: info@gressel.ch
Web: www.gressel.ch
Siba Metallverarbeitungs GmbH
Industriestraße 29
35684 Dillenburg
Telefon: +49 2771 83350
E-Mail: info@siba-dill.de
Web: www.siba-dill.de
