In cooperation with the plant manufacturer Eisenmann, Randon, the largest manufacturer of trailers and freight wagons in Latin America, has built a new production line in Araraquara, some 270 km northwest of São Paolo. Since April 2018, trailers and wagons are being welded, painted and assembled in a combined line over a length of 500 m approximately. Different wagon and trailer lengths of 9 to 22 m are feasible. Randon's product portfolio includes oversized sugarcane double trailers. "The interesting thing about this concept is the combination of welding, painting and assembly processes in a continuous line. It is thus possible to achieve a short clock cycle and a calculated capacity of up to 18 wagons per work shift", explains Jochen Keinath, project manager at Vollert. At full capacity wagons and trailers can be completed every half hour.
13 Rope conveyor drives integrated in a single line
Initially, the frame structures set up on dummy buggies are still fed manually into the system. Vollert's automatic conveying line starts at a weight of 10 tons within the welding range - at the end of the line the total weight of the workpieces can reach up to 25 tons. A total of 13 rope conveyor drives, handle the buggies forward movement after each work step. For this purpose, the drives are arranged one behind the other to allow individual forward feed at the workstations after acknowledgment. At the end of a conveying section, the rope conveyor transfers the workpiece over to the next section. "Rather than using a single rope conveyor for the entire conveyor line, the single drive concept allows for individual dwell times of the workpieces at the respective workstations," explains Jochen Keinath. "In addition to that, five buffers are located before painting area that follows."
Automatic distribution in the painting and assembly zone
The painting area spans over a length of approximately 190m. It starts with the distribution center equipped with five buffer spaces and a heavy-duty transfer platform from Vollert, which handles the distribution of trailers and wagons on demand. The workpieces enter into the robot blasting cabin, and are moved from there by means of the rope conveyors first to the primer station, then to the painting station and finally through the dryer cabin where at the end two more buffer positions are placed and a second transfer platform. From here, the conveyor line continues on two parallel assembly lines, each about 90m long, where the wheelsets are fitted to the trailers and wagons. The extension of a second paint line is in planning, so that also this area can operate as a double-lane line, if needed.