Automation and robotics are increasingly common in metal forming, processing, and handling, sawing operations are among the most effective applications. Robot-assisted systems are being assigned to handle more of the work steps that follow the sawing process, starting with handling before and after the sawing sequence, through forming, to removing the formed part and further handling to subsequent stages — like deburring, weighing, centering and marking, all the way to sorting and stacking on pallets or in containers. Robots make production more flexible and efficient, improve working conditions and significantly reduce operating costs.
There are operating and performance factors guiding these changes. In recent years, the demands have increased on metal processing in every industry, from service centers and warehouses to forming, to machining, fabricating, and assembly in system and OEM operations. Manufacturers choosing to adopt robotics want greater flexibility, from batch sizes of one item to large-volume production. Also, the variety of materials and sizes of workpieces to be used by manufacturers is increasing steadily.
At the same time quality standards are rising, and there is continuous pressure to cut costs. To maintain cost-competitiveness against global economic standards, manufacturers need versatile and efficient solutions for a wide range of production tasks.
Multiple robotic applications — Sawing technology is a critical step across all types of metal processing and offers many opportunities for optimization. More and more operators of sawing systems are adopting intelligent technologies to link their work processes, and automating them with robot support. The benefits are obvious: Industrial robots are fast, reliable, and precise, and if necessary they can work 24 hours a day without human intervention. They don’t grow tired or call in sick, and they can handle a wide range of tasks when equipped with the necessary tools.
“Our robots help us with a number of handling and conveying tasks, and efficiently perform many machining steps,” according to Volker Bühler, group manager for robotics for Kasto, a sawing and storage technology specialist.
Automated sawing starts right at the point of material feeding. The material to be cut is conveyed to the machine by means of suitable equipment, for example roller conveyors or magazines, thus sparing workers the effort of lifting and carrying, and reducing the risk of injuries. Depending on how it is equipped, a sawing machine also can run with a human attendant. Material is fed automatically, and an intelligent machine control system sets all parameters — e.g., cutting length and cutting speed — based on the job data. Thus, state-of-the-art production saws can carry out a variety of jobs in sequence, with different materials and diameters, and operate autonomously over long periods.
Automatic from start to finish — Industrial robots also have considerable potential when it comes to handling and processing finished cut parts. For example, they can remove them from the machine, thus relieving workers of this repetitive task. When equipped with appropriate tools, robots can also perform tasks like deburring, chamfering, marking, centering or measuring workpieces. Cut parts can be weighed, sorted by size or job, and stacked on pallets or placed in containers. The parts also can be transferred directly to a driverless transport system. “For complex processes involving various work steps, we also use combinations of different robots and clamping devices,” Bühler explained.
When large quantities of material are sawed with only a few different component geometries, it is relatively easy to automate the downstream processes. The situation is different with custom sawing involving diverse materials and dimensions. “The greater the variety, the harder it is to cover all the possibilities,” according to Bühler.
The choice of robot tools is an important factor, too. A robot must be able to deal with all the objects it encounters while using as few aids as possible. This reduces procurement costs, minimizes idle times, and increases productivity. Users have a choice of mechanical, magnetic or vacuum-operated grippers. The grippers should be as compact as possible to give the robot easy access to the cut parts.
On course to Industry 4.0 — With the help of the right components, sawing can be combined with other automated operations to create complex, highly integrated systems that are connected seamlessly in a continuous material flow. This includes upstream storage as well as downstream handling and processing.
For example, Kasto implements combined storage and sawing systems for its customers in which all storage, handling, sawing, marking, palletizing, and bundling processes are completely automated, from storage of the raw material to retrieval of the cut parts. The control software can be linked to existing ERP systems for greater transparency and efficiency.
Sawing can be integrated with other processes (like turning or milling) in digitized, self-configured production systems, such as the manufacturing concept envisioned by the Internet of Things or Industry 4.0 initiatives.
Automated sawing technology offers significant advantages to users, too. Many processes can run unattended and much faster, which increases productivity and reduces the need for personnel. It is easier to make up volume or workflow differences when employees are ill, and robots can keep working even during breaks or after shifts. The result is lower personnel costs and greater flexibility in terms of capacity utilization.
Manufacturers can react more easily to order peaks and dramatically reduce idle times, which can make a big difference economically: “We’ve calculated that, depending on the shift model, an investment in an industrial robot with a machine like our KASTOvariospeed saw pays for itself in less than a year,” Bühler said. “When you consider that systems like this are used for more than 10 years on average, users can reduce their operating costs for a very long time.”
Robot technology also helps to improve working conditions. It relieves employees of heavy, tiring and monotonous tasks. The risk of accidents and injuries is reduced. Moreover, the cut parts are of better quality because robots machine them with equal precision, sort them reliably, and stack them neatly. This provides benefits not only for operators of automatic sawing facilities, but for their customers, too.