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Increased productivity with fully automatic digital printing lines that thanks to the Pre-Feeder Robot of SERRA


Since 2014 when the very first single-pass digital press was launched on the market, the number of installations of this type of printers has increased exponentially. New brands of presses are appearing in the market and the technology is rapidly spreading through the main corrugated companies in every worldwide corner. The potential of this technology is vast, and we are seeing how it is expanding well into other business segments such as display graphics, which opens up many possibilities. Competitiveness is close, and the improvements are constant. One of the latest developments for the single-pass digital printing lines is the Pre-feeder Robot designed by Serra in 2019, which will delight the customers making a step forward in terms of productivity and innovation. 

SERRA, a world-leader supplier 
SERRA is a family-owned company with more than 35 years of experience in the design and manufacture of machinery for the corrugated
cardboard industry. Serra sells both to other machinery manufacturers in the sector (OEM’s) and to cardboard manufacturing companies (end customers). SERRA’s main strengths have always been innovation, reliability, and efficient production. The company underwent an expansion last year, increasing the production area three times more, with a total capacity of about thirty thousand square feet. SERRA is a specialized provider with a wide range of top-quality products in  feeding and stacking solutions. Serra has become the world’s leading supplier in variety and installed base peripherals for single pass digital printing. 

Why a robot pre-feeder? 
The design of the gripper - patented by SERRA - and its movement with the robotic arm enables the option of flipping the boards or not when required. This functionality opens many possibilities and responds to a market demand. Normally, the stack of corrugated boards comes printable side down, which is supposed to be the outer side of the box. Therefore, we will need to flip the boards before printing because the digital presses always print on top. However, sometimes, on some jobs, it may not be necessary to flip the boards to print the inside face of the box. 

The Robot Pre-feeder can be installed at the initial stage of the installation along with the basic printer line, or in a second stage as an upgrade to convert the line from manual mode to fully automatic. The upgrade allows for a volume increase in productivity
comfortably with a reduction of 1 or 2 operators and minimal exposure to security risks. Therefore, the return on investment of such equipment is calculated to be between 2 and 3 years. The Robot Pre-feeder increases the productivity of the digital printing line with a fully automatic operation at high speed, ensuring efficiency and operator safety. 

The innovative design is composed of independent bodies that enable a very flexible configuration, in which the installation can be customized according to the plant's supply logistics system and the available space. The Infeed Table receives the stack of boards and places them in the center. Once the stack is centered, it is picked up by the Bundle Breaker, whose frame moves up and down to reach the top position of the stack, where it separates a bundle from the stack and pushes it into the gripper. The transition between the Bundle Breaker and the Gripper is through overlapping belts that guarantee a gentle handling of the boards and not damage them. The Gripper and the Robot are the key elements to achieve the advantages mentioned above. The Roller Table squares and places the bundles. When using the dual line feed function on the feeder, the bundle is positioned accordingly. The Telescopic Table moves the stack towards the feeder through a flow of shingles, allowing for a friendly and gentle handshake between the Pre-feeder and the Feeder. The movement of the Telescopic Table is motorized and can be adjusted according to the length of the sheet format. 

Plant integration 
SERRA has also developed inbound and outbound logistics transportation around the digital line with different kind of conveyors, turning tables, palletizers, and stack flippers if required. This response to the demands of the market, in which the tendency is to minimize the number of suppliers over the different processes of the corrugated box making. The aim is to ease the communication flow, the interface between components and probably the overall costs of the projects. Such transports are adapted to the needs of the customer, and it can be integrated into the 
logistic plant system.

SERRA, global provider of solutions for the corrugated industry 
Since its inception in 1984, the SERRA family business has been an innovator and global provider of machine solutions that have been key to the corrugated cardboard industry and have positioned it as an international reference manufacturer. SERRA helps its customers achieve higher quality and productivity by optimizing workflows with lower operating costs thanks to two main competitive advantages: local technical support and its innovative solutions that often redefine market standards, including The die-cutting solutions, peripheral equipment and installed bases for digital printing and the manufacture of auxiliary equipment stand out.
Currently, the brand is positioned as one of the main players in the corrugated cardboard industry, not only at the design and manufacturing level, but also due to its global coverage in the application of high-tech solutions to optimize workflows. And as a partner in digital printing, storage solutions and AI security applications.