Automatic saw with unattended sorting keeps up with steel trader’s increased demand

Situation

Schmolz + Bickenbach Stahlcenter AG, or Schmobi for short, located in Bronschhofen, Switzerland, is a steel trading company for the Swiss machine industry. The facility has an extensive material store with high-bay warehouses, as well as a variety of machines and a fully automatic sawing center.

On a floor area of nearly 270,000 sq. ft., about 100 employees sell, process, and fabricate numerous materials, including bright steel, stainless structural steel, steel tube, tool steel, and castings. The warehouse holds more than 22,000 tons of material.

More than 10,000 parts a day—about 2.5 million per year—are cut on more than 30 machines. “Our orders include large batches of more than 10,000, as well as single items,” explained Thomas Plüss, communications officer.

As a result of staggered working times, a workday at the steel trading company is about 10 hours. This means the machines are used heavily, and some run throughout the night.

“The demands on our saws are enormous. We therefore need machines which process workpieces with different diameters quickly, cleanly, and economically and, above all, which work reliably and without errors,” said Works Manager Robert Schönenberger.

The company realized that two of its saws had become obsolete and were unable to cope with the continuously increasing number of cut parts. “The demand on us for ready-cut blanks has been continuously increasing in recent years, and the capacity of the two existing saws was no longer sufficient,” Schönenberger said.

Resolution

Schmobi replaced the two obsolete saws with a Kastotec FC 4 fully automatic band saw from Kasto Maschinenbau GmbH & Co. KG for cutting round, square, and flat material as well as tubes and profiles.

The band saw is suitable for cutting difficult-to-machine materials such as corrosion-resistant steel or tool steel in dimensions from 0.39 by 0.39 in. to 16.9 by 16.9 in. Fitted with Kasto Performance Cutting, the band saw is designed for the user of carbide saw blades, which provide long service life.

The saw has a precision of up to +/-0.004 in. per 3.9 in. cut length, with a cutting speed up to 590.5 FPM. “We can saw different materials and diameters extremely economically,” said Kurt Thoma, sawmill group leader. “The minimum remnant piece length in automatic mode is only about [1.37 in.]. This enables us to use our material efficiently.”

The saw is loaded using a magazine with space for several bars. A magnet system delivers material from the store to the machine. Items that are kept in the high-bay warehouse in the adjacent hall are brought in by crane. The saw also has an automatic system for sorting cut parts. It separates and collects the sawed parts, arranged by purchase order on a stacking table or in one of several waiting containers. This feature also enables the saw to operate unattended over an extended period.

“Our staff fill the magazine with the appropriate material in the evening before they go home and program the saw accordingly to the customer’s requirements,” explained Schönenberger. “The changeover between two orders takes place automatically. The saw runs overnight, and on the following morning, the items are already cut and, thanks to the cut part sorting system, arranged ready for unloading. This has enabled us to significantly improve our performance.”

The machine features an EasyControl saw controller. “After just a short time, everything was running as if on its own,” said Thoma. He pointed out that the new graphical interface “makes everything clear. You can get to the required option intuitively, which considerably simplifies day-to-day working.”

Kasto Maschinenbau GmbH & Co. KG

www.kasto.com