Customised production with Stratasys 3D printing

Marchesini Group S.p.A. is an Italian manufacturer of automated packaging machinery and an established supplier to some of the biggest names in the pharmaceutical, cosmetic and food industries. As one of Stratasys’ largest customers in Europe, the company has revealed how it has embraced an entirely customised production business model to meet the needs of the international packaging sector – with its arsenal of industrial-grade Stratasys 3D printers at the heart of its manufacturing operation.

Headquartered in Pianoro, Marchesini Group has a dedicated 3D printing facility featuring 10 Stratasys production-grade FDM 3D printers – a large-scale Fortus 900mc, four Fortus 450mc and five F270 systems – as well as two PolyJet multi-material 3D printers. The technology is used throughout the design, development and manufacture of the company’s flagship cartoning machines, as well as several other packaging lines. Every machine produced is tailored to a specific industry or customer’s production process, which is critical in ensuring optimum performance and efficiency when deployed in the field.
“At Marchesini Group we say that ‘extra-ordinary is our ordinary’, meaning that we are faced with challenging, entirely customised projects on an almost daily basis,” says Mirko Fortunati, who is responsible for co-ordinating the mechanical workshops at Marchesini Group. “However, producing complex, bespoke parts with traditional manufacturing methods has proved extremely costly and
time consuming, which is no longer suited to the growing demands of today’s packaging manufacturing industry.
“Importantly for our business, Stratasys additive manufacturing has enabled us to overcome these issues and adopt a customised production model,” he continues. “Integrating industrial-grade FDM 3D printers into our production process has drastically reduced our part lead times from several weeks to a few days. Added to that, we can cost-effectively produce the exact quantity of parts we need, without requiring expensive tooling or machining. Having this on-demand production capability enables our engineers to take advantage of the greater design freedom enabled by 3D printing, which has empowered Marchesini Group to achieve higher-quality results for our customers.”

Importantly, this on-demand production capability also extends to maintenance and repair. With its packaging machines installed at customer locations throughout the world, the company is now able to quickly and cost-effectively 3D print customised replacement parts on-demand with no minimum order requirement. Not only does this allow Marchesini Group to deliver spare parts to customers in record time, it eradicates the need for costly storage facilities of spare inventory.
The team at Marchesini has 3D printed thousands of functional parts and components for its packaging machines, including protective cases, cable support systems and junction boxes, to name but a few. These applications are particularly important for the company’s robotic packaging systems, where every single component matters in order to ensure the robot’s agility, precision and speed of movement. This is an area where high-performance 3D printing materials have made a big impact.
“Using tough thermoplastics such as Stratasys’ FDM Nylon 12CF filament or ULTEM 9085 resin in place of traditionally machined metal components, has enabled us to reduce the weight of some parts by at least 30%,” explains Fortunati. “This not only increases the speed of movement and productivity of the robot for our customers, but it lessens the rate of degradation. In addition, these 3D printing materials comply with specific industry regulations, which importantly enables us to expand this technology into even more production applications – helping us to further innovate our products for customers.”
Marchesini Group is also using Stratasys PolyJet technology to produce components for applications requiring the combination of two or more materials.
“One great example of this technology is for the production of grasping pincers, which are designed to handle light items such as package leaflets or smaller jars,” explains Fortunati. “With the advanced multi-material 3D printing capability, we can produce complex designs that combine hard and rubber-like materials in a single print – something that would typically take multiple processes to create, costing us time and money.”

The battery of Stratasys 3D printers within Marchesini Group’s additive manufacturing department is currently running round the clock.
Fortunati concludes: “It’s fair to say that additive manufacturing is an integral part of Marchesini Group production. In 2019 alone, we recorded a total of 22,480 hours of operation for our FDM 3D printing equipment – equating to almost 15 hours a day. And for our two PolyJet 3D printers, a total of 1700 hours of operation, the equivalent of about 8 hours a day. As we continue to expand these technologies across our design and production process, we can expect these figures to be even higher in the future.”
Established in 1974 by virtue of the shrewd intuition of Massimo Marchesini, over the years the company has grown from a small, local business into a major industrial enterprise, thanks to a continuous process of mergers and acquisitions of complementary companies. Despite its present-day multinational dimension, the group has never betrayed the human spirit and artisan production that characterised its early days, and these traits still exist today alongside the latest innovations in robotics and digitalisation.
For further information www.stratasys.com

Are grinder guards over-designed?

Guards on grinding machines are particularly important for ensuring operator safety. Grinding wheels seldom burst, but when they do, there is a great risk of serious injury to the machine operator. Recent studies suggest, however, that the enclosures commonly used in gear grinding machines, for example, could be over-designed.

Investigations conducted by the VDW (German Machine Tool Builders’ Association) and the Institute of Machine Tools and Factory Management (IWF) at TU Berlin, reveal that it is possible to use safety guards which are up to 70% thinner, depending on the width of the grinding wheel. These findings are now leading to changes in ISO standardisation.
The minimum wall thicknesses for safety guards are specified in ISO 16089. For example, there is a directly proportionate link between the requirements concerning primary protective covers for gear grinding machines and those for the full enclosures located further away. The reason is that no specific safety precautions were initially specified for the safety guards of gear grinding machines as they were not explicitly included in the preceding standard, EN 13218. However, this proportionate scaling has been repeatedly questioned, including by the JMTBA, as it results in overdesigned polycarbonate safety guards and screens.
“Our burst and impact tests showed that the thickness of the enclosure wall can be reduced by up to 70%, depending on the width of the grinding wheel,” explains Simon Thom, group leader for machine tool technology at IWF (TU Berlin). “This is very good news for the machine tool manufacturers, who are keen to avoid excess weight in their machines. Reducing the thickness of a sheet steel housing by half a millimetre, for example, will save 4 kg/m2 in weight.”
For further information www.vdw.de

Entry level universal grinder

A new universal cylindrical grinding machine from Swiss specialist Kellenberger majors on providing high value at the entry level, while offering reliability, precision and high productivity via its state-of-the-art intuitive programming function.

Available in the UK from Jones & Shipman Hardinge, the Kellenberger 10 (K10) combines proven technology using many Kellenberger components and sub-assemblies from the established K100 machine, coupled with the latest programming technology. For instance, Kellenberger Blue teach/programming software enables semi-skilled operators to use the machine, thereby optimising use of the work team. Kellenberger Blue solution software is accessed through a FANUC 0i-TFP CNC control with a 19” touch screen.
In standard format, the machine can accommodate workpieces up to 1000 x 400 mm in size with a top table weight capacity of 100 kg. The table profile is also a proven Kellenberger design with the full length wheel dressing interface located on its rear to reduce re-tooling work and extend wheel dressing possibilities.
K10 models feature generous X and Z-axis strokes (365 mm in X, 1150 mm in Z), collision-free operation and dressing ratios. The low-maintenance, high-precision linear guide on the X axis and the flat sliding V guides on the Z axis are equipped with optical absolute linear position measuring systems. Furthermore, the B axis is designed as an automatic indexing axis (1° Hirth gearing) with high positioning accuracy and a +30°/-210° swivel range.
The K10 also offers the ability for users to expand or customise its capability by adding a range of optional equipment such as a second external grinding wheel, larger grinding wheels, a tailstock, gap control and balance sensors, and measurement control via probing.
For further information www.hardinge.com

£1.2m project support

The University of Derby is supporting an advanced manufacturing project that has secured a £1.2m UK Research and Innovation (UKRI) grant.

Funding has been released for a project led by engineer Ayantika Mitra of Hampshire-based firm TISICS to transform advanced materials manufacturing through digital technologies. The four-year project, named ‘RAiSE: Radical Approaches in new materials Science and Engineering’, will develop tools to enable the rapid certification and qualification of new lightweight products for spacecraft and aircraft.
The University of Derby is providing advanced materials and expert support.
For further information www.tisics.co.uk

Adding control to contour grinding

The two-machine X series of two- and three-axis surface grinders from Taiwan-based Perfect has long been a part of RK International Machine Tools’ portfolio of precision grinding machines. Now, thanks to the addition of full CNC in the form of the Siemens 828D control, these machines have gained even greater versatility, with the three-axis versions now able to perform full contour grinding as standard.

The X25 with its 250 x 500 mm table – and the larger X36 with 300 x 600 table – feature 550 mm and 600 mm clearance between table and spindle centreline respectively. Both variants are based on a construction that was developed through FEA for added stiffness and support. Spindles are also high-performance P4 units with precision angular contact bearings delivering runout of <2 μm. The spindle itself features an inverter giving users a choice of spindle speed to suit specific materials. Craig Digweed, RK International’s product manager - grinding products, says: “With the addition of full CNC control from Siemens, the X series provides, as standard, cycles to cover surface, crisscross, plunge and pitch [same pitch and same depth] grinding. However, customers can now specify optional cycles such as stair, side, profile and contour grinding, giving them much greater control over their operations.” Table speed ranges from 1 to 25 m/min, dependant on machine specification, with a cross feed of 1100 mm/min on all machines. A table mounted, three-piece dressing diamond is standard and, to accommodate the variety of additional grinding cycles, rotary and roller dressing devices can be offered for wheel forming options. For further information www.rk-int.com