A well-known group of five companies, OMET is today mainly involved in the design and construction of machines for printing and converting of labels and flexible packaging, and design and construction of machines used to make paper napkins. The OMET Printing Division is the group’s company, which is specialised in producing printing machines using combined narrow and medium web technologies, characterised by their operative flexibility, production efficiency on all types of runs, versatility in the use of different materials to be printed and offering customised configurations to satisfy every customer’s need.
After decades of experience and innovation in the printing market, OMET machines have combined simplicity of use with low rejection rates, rapid work changes efficiency and reliability over time. But what exactly do the OMET machines produce? They produce labels of all types, plastic films, folding cardboards and special applications.
The Lecco-based company has won a leading role in the world market over time and boasts of more than 1,600 installations all over the world today. Their customers range from small printers to labellers and major multinationals, producing and printing flexible packaging.
In 2014, OMET visualised the need to design and produce second-generation machines. Thus began the search for the most appropriate partner, which became an extremely competitive benchmark, involving various potential suppliers. At the end of the selection, the Lecco-based company opted for Kollmorgen as its solution provider. They were considered the best at being able to fulfill all requests and also be able to implement technological innovations—the first development was to be a new machine whose quality of print and flexibility lay somewhere between the mechanical solution of the model X4 and the fully servo-driven X6 series.
Other important targets included the reduction in the size of the electric cabinet and the volume of cables, modular production of the machines, standardisation of the field bus and the reduction of components, not to mention important matters like energy saving and print precision. Another challenge to be overcome in the development of the new machinery came in the form of the maintenance of existing automation software and a minimum impact of changes with respect to time-to-market and the safeguarding of R&D costs. These are the essential characteristics which are fundamental to the project's success and meeting these demands of the customers is significant.
Speaking on overcoming these challenges, Fabio Massari, Senior Sales & Key Account Manager, Kollmorgen—Italy, explained, “In addition to offering OMET the guarantee of being able to fully satisfy all needs, Kollmorgen also introduced a new Direct Drive motor that can eliminate the Gear Marks effect. It allows for the development of an innovative hybrid/semi-motorised machine. OMET has also considerably improved the use of components relative to drives and safety, eliminating most of the electric cabinet and reducing cable length by around 70%.” The Motion Control specialist has responded to the need for efficiency with a compact, modular design and has addressed the concern of safety by using AKD-N servo drives, Direct Drive Cartridge DDR motors and KSM safety modules.
Efficient and compact servo drives
In order to reduce or eliminate the mechanical kinematics, Direct Drive Cartridge CDDR servomotors have been used together with AKD-N decentralised drives. The CDDR motors enable a direct control of movement, without using mechanical transmissions, which result in reduction of maintenance, need for spare parts and safeguard the precision level of the entire machine over time. Motor assembly is fast, involving reduced cogging with a built-in high-resolution sinusoidal encoder and continuous torque of up to 510Nm.
The AKD-N decentralised servo drive is Kollmorgen’s proposal for designing more efficient machines, more simply, which can combine innovative technology and exceptional performance with an extremely compact design. Due to the robust structure and protection grade IP67, the AKD-N Kollmorgen decentralised servo drives are positioned close to the motor, reducing cabling, and thereby, reducing the dimensions of the electric cabinet. Plug-in connections, free choice of motor, assembly at the most appropriate point as well as a wide range of functions using decentralized AKD-N servo drives, even complex Motion Control architectures can be developed, based on EtherCAT field buses.
The system offers everything needed for the design of new-generation machinery without giving up on simplicity. The hybrid cable with a diameter of just 11 mm (patented system) integrates the power supply, safety (STO) and the EtherCAT field bus. The connection to the motor is also simplified with just a single cable for power, brake control and feedback. By doing this, more than 80% of machine cables are saved.
Advantages of AKD-N decentralised servo drive
The AKD-N decentralised servo drive comes with several advantages. This i cludes more compact machines, smaller and lighter compatible electric cabinets, servo drives near the motor, simple cleaning and maintenance for hygienic environments, high operative safety, due to the robust structure, machine debugging and faster testing due to reduced connections, greater flexibility in machine design which is modular and scalable and finally, eliminating the need for a protective casing due to the protection grade IP67, which is due to the robust structure.
Safety in all stages of manufacturing is an essential requirement today. This aspect has been satisfied with the KSM safety modules. The safety of the axes has been interpreted by Kollmorgen with Motion Safety. It integrates the safety logic and monitoring directly into the KSM controller available in a compact and modular version. “Use of the technology developed by Kollmorgen has allowed us to achieve the target control performance while at the same time, it has reduced cabling and the cost of automation,” explains Nicola Pezzolato, R&D Elect., Department of Omet.
Xflex X5: Compact, ergonomic & flexible
XFlex X5 is a machine that offers all the main characteristics of OMET flexo p inting technology, in a compact, ergonomic solution. Due to the servo drive printing units, the user can perform sliding and doubleprint routing operations, which allow the machine to work on all types of materials (differently from other machines on the market) with high quality printing results.The perfect blend of flexibility and innovation makes XFlex X5 the printing solution offering the best return on investment in terms of market result of the narrow web printing of labels and flexible packaging. Additional features of this technology include:
Short paper pass: The innovative concept of the gearless flexographic printing unit with a UV lamp installed directly on the print cylinder drastically reduces the level of rejects during the start-up phase
Rapid ink change system: In less than 30 seconds, the ink cassette can be replaced on a print unit due to the innovative interchangeable cassettes
Rock’n’Roll matrix stripping unit: The exclusive OMET stripping system allows for the separation of reject adhesive material from die-cut labels, without slowing the machine’s production down, even with complex label shapes
Vision-1: This is a fully automatic system that enables the high-speed digital scan of print quality and the automatic correction of the print register without operator intervention, drastically reducing the quantity of rejects during print start-times
Additionally, some of the technical data of the XFlex X5 include printing widths available: 370 mm (14"4/8) and 440 mm (17"2/8), print formats available from 5"4/8 to 24" (version 370 mm) and from 6" to 24" (version 440 mm), maximum speed of 190 m/min, a print cylinder flexo printing technology and automatic registration control and correction
The design, which began in 2016, saw the development of Xflex X5 that same year and took three units to the market, installed and functioning in three different countries of the European market. Customers have expressed complete satisfaction with the machine and the targets set by OMET have been achieved.
Exciting opportunities in the future
The OMET mission is to constantly find new solutions to improve customer production methods, offer the best technology to increase process efficiency and build machines using increasingly robust materials to improve their reliability and duration over time. In this journey, it has found high quality and innovation in their high-tech partner, Kollmorgen. With this exciting partnership, the next evolution for the future is being considered with a new-generation model and offset printing units on the custom Varyflex machines.