In order to provide its customers with highly efficient operating sequences and the fast delivery service they have become accustomed to even for small and very small batches, Schmolz und Bickenbach Stahlcenter AG of Wil, Switzerland, has installed a fully automated Friedrich Remmert sawing cell. The complete system ensures that all process sequences are intelligently linked from the placing of the raw material into storage and the optimized, fully automated loading of the machine right through to the sorting of sawn blanks in accordance with the requirements of individual orders. As a modern steel service center, the Swiss subsidiary of the Schmolz und Bickenbach AG steel group specializes in the storage, cutting and processing of high-quality steel products.

The Swiss company's two fully automated high-bay storage areas alone hold over 20,000 tonnes of steel, which is taken to the in-house sawing center and cut to the required approximate length just in time using 30 high-performance saws.

To reduce the time spent on material handling for its many small-batch orders, the company decided to invest in a state-of-the-art Remmert sawing cell.

The modular, fully automated processing cell consists of five different system components: one cassette storage system, optimized to the available space, two single-rod handling systems (pick systems for short), the PRO FMS flexible production software, four powerful Kaltenbach saws and two picking robots.

* Project requirements - Schmolz und Bickenbach Stahlcenter had some quite stringent requirements when it came to technology and the implementation of its project.

On the one hand, the required solution had to fully automate small-batch production.

On the other hand, by installing the sawing cell, the company had plans to increase its stock turnover by 25%.

To achieve this aim, a three-shift system was to be introduced in the store, which would require a maximum of two employees per shift.

Walter Hegelbach, manager of the subsidiary, summed up the collaboration with its supplier as follows: 'In Remmert we have found a competent partner, who meets every one of the expectations and requirements we had in mind when allocating this project.'.

* Material handling - in order to make logistical operating sequences within the store as efficient as possible, Remmert integrated the sawing cell into the existing flow of goods and data through the central store.

The following process sequences have been in place since April 2006: Schmolz und Bickenbach Stahlcenter records the raw materials arriving at the Goods Receiving Department and enters all key data in the SAP HOST system.

The steel is then stored in the two existing, fully automated high-bay storage areas.

The steel expert now uses steel from these storage areas to process any orders requiring either no blanks or blanks that use a great deal of material.

Schmolz und Bickenbach Stahlcenter also equips the new sawing cell with material from the high-bay racks.

A shuttle system transports raw materials to the sawing cell, where all small-batch orders are processed fully automatically.

* Space-conscious storage system - the sawing cell's compact cassette storage system holds around 1,000 cassettes, each with a load capacity of three metric tons, on a store floorspace of only 440m2.

As the load carriers are subdivided into several sections, the store has the space to store around 5,000 different items.

The store features two automatic goods receiving stations as well as two manual storage stations.

Matthias Remmert, managing director of the Remmert company group, described the fully automated storage procedure thus: 'At the automatic stations the material is measured automatically and transported to the sawing cell's fully automated handling systems, the pick systems, by means of a chain conveyor.

These fully automated pick systems lift rods individually and place them in a cassette, which has already been defined by the storage software.' Once the pick systems have transferred the load carriers to the storage system's rack feeders, these feeders transport the cassettes to the appropriate storage location.

As half of the store is dedicated to the stockpiling of stainless steel, the other half is reserved exclusively for rolled steel.

The two materials are kept separate throughout the entire machining process.

* Handling systems - as well as enabling materials to be placed into storage fully automatically, Remmert pick systems also provide a mechanical link between the store and machine tools.

The pick systems take the appropriate raw material from the eight goods issuing stations in the store and feed it to the machine tools.

In this way, each pick system supplies two directly connected high-performance saws.

As there are two retrieval stations per saw, rods are changed very quickly.

'At a traveling speed of over 100 meters per minute and with the lifting and gripping axes set to maximum capacity, each pick system can change up to 50 rods per hour,' said Remmert of the performance of the handling systems.

Once automatic cuts have been made, the pick systems perform the return transfer of the residual material.

Remmert has developed two special vacuum traverses for the purpose of conveying very small amounts of material.

A vacuum is created when these traverses are taken up by the pick systems.

In this way, even flats that are 5mm to 20mm thick and 40mm to 260mm wide can be transported fully automatically.

* Intelligent storage software - the handling systems are controlled by the PRO FMS flexible production system.

This storage software is the intelligent link between all sawing-cell components and performs central production control functions.

Hegelbach said: 'The FMS software controls all cell-technology storage and machining processes and makes our process sequences much more efficient.' All key data relating to the sawing machines, materials and parts lists is managed by the production system.

The software system uses computerized customer orders and production parts lists to supply the four sawing machines with material for machining.

PRO FMS orders the appropriate raw material from the store, instructs the pick system to transport the material and transfers technology or cutting data relating to the order to the corresponding sawing machine.

As part and parcel of this process, the software takes machine utilization and availability, as well as scheduling, the current store situation, and other optimization criteria into account.

Once automatic cuts have been made, the flexible production system creates a label bearing the order number, item number, type number, and part number of the sawn blanks and initiates the return transfer of the residual material.

The software also communicates with the two sorting robots, which are located between the sawing machines and the sorting station.

Furthermore, PRO FMS defines the type of bins to be provided at the 40 pallet locations in the sorting station and the pallet on which the robots are to deposit each order.

* Robotics - the sorting robots retrieve the blanks from the sawing machine outlet and place the items in a suitable bin fully automatically to make up the order.

Each robot is equipped with three different gripper arms and an automatic transfer system.

The robot controller uses the data record provided by the FMS software to establish whether round, flat, square, or hexagonal material is to be picked up.

The robots select the appropriate gripper and monitor operations by means of laser photocells.

The robot software determines how parts are then assigned to pallets.

Once this production step has been completed, the system notifies the FMS software of the specific location where the parts have been deposited.

To ensure that orders can be processed quickly, every pallet location in the sorting station is also equipped with a signal lamp.

As soon as a pallet is full and can be replaced, the production software activates the signal.

* Impressive results - in the course of restructuring, Schmolz und Bickenbach Stahlcenter is also dispensing with its existing residual material store.

Up until now, the steel expert has been using residual material left over from other orders to process small batches.

The company stored these short steel rods on shelves, which took up a lot of space and were also very difficult from a handling perspective.

Although the sum total of the stock in this store was recorded in the HOST system, the process of finding the required material and transporting it to the saws was very time-consuming.

As a result of restructuring, the residual material store has been fully integrated into the sawing cell and, thus, into the automated production process.

Hegelbach was pleased: 'By investing in the new sawing cell, we can ensure that our customers' orders are processed quickly, flexibly and accurately.

The fully automated manufacturing process also reduces potential sources of error.'