The modernization involved the cutting line, the dryer loading and unloading areas, the new tunnel dryer and the setting machine.
Cutting line and dryer car loading
The first part of the project comprised the supply of a new Sabo DF800 electronic cutter to replace the existing machine for cutting the extruded blocks. The new cutter is able to work with single- or double-column extrusion. It is equipped with inclined cutting wires and automatic wire-cleaning system, ensuring very smooth and accurate cutting.
After being cut, the wet blocks are transferred on a conveyor belt to the new loading robot, which is in total synchronization with the belt and loads the wet products onto the dryer laths. The gripper robot is able to handle all different types of products.
In the wet area, Sabo installed a new chain transportation system for transport of the frames with wet products up to the position of the new system with a fork for loading dryer cars. In front of the loading position, a line with chains for transporting the empty frames was installed together with a gripper for the empty dryer frames to enable the storage of empty frames, before they are returned to the robot’s wet loading area.
This dryer is an improvement on the conventional tunnel dryer and has been developed by Sabo for products with high drying sensitivity. The design ensures high humidity saturation content, strong ventilation on both sides of the dryer cars, as well as symmetrical temperature conditions over the cross-section of the dryer.
The internal ventilation is characterized by strong blowing and drafting effects through a high-volume technique up to the point when most of the shrinkage has taken place. After this point, internal ventilation is performed with conical fans equipped with motors outside of the dryer, so that high temperatures (more than 100° C) are possible. At this final stage all the remaining humidity can be quickly removed.
The dryer is controlled by a modern SCADA system that incorporates all the proven regulation techniques. The system follows certain temperature, humidity recipes in relation to the perforations, materials and production capacity. The dryer is supported by small-size heat exchangers that only have a minor impact on drying energy.
After the drying process, a new system with a fork unloads the frames from the dryer car. A second new robot equipped with a special double gripper removes the dry products from the frame. The robot deposits the products on the new belts, which transfer the dry products to the setting line with programming bench and setting robot. A tilting unit can tilt the products if necessary before they are loaded on the kiln car.
After programming, the layers of bricks are transferred to the final conveyor bench by means of a pushing system and the new setting robot loads the bricks onto the kiln cars. The flexibility of the robot offers the possibility to have several different settings on the kiln cars, handling the total range of bricks produced. The kiln car is fixed at the exact loading position by a centring system, ensuring stable positioning of the car during loading.
Apart from the installation of new equipment, the project comprised the continued use of the existing equipment, too. Sabo also supplied new control panels and programming of the whole wet-dry lines, including new machinery that ensures the efficient operation of the line.
Following the modernization, all the areas, cutting, loading and unloading of the dryer as well as the setting area are controlled by only two operatives.
This project follows a series of other recent projects in Europe as well as many others in the past that Sabo has completed successfully.