Objective:
The complex and ambitious geometries of marble objects designed by design studios were presenting O&G Raimondi with the challenge of successfully combining innovation and craftsmanship, while simultaneously meeting competitive delivery times.
Solution:
Raimondi turned to special machine manufacturer Benelli, which built a compact five-axis CNC machining centre – featuring a FANUC 31i-B5 CNC – dedicated to marble processing.
Result:
Thanks to the Jeco machine, Raimondi has been able to achieve greater productivity in terms of both flexibility and machining precision. Particularly appreciated is the flexibility of machining with regard to turning and producing particular shapes, without any interruption in the cycle. The simplicity of programming allows time savings of up to 20%.
Marble has always been a valuable material with unique and attractive characteristics. Innovative visions of architecture and interior design have given marble a new lease of life and it is now the protagonist of details, furnishing accessories, surfaces and objects of almost infinite kind.
The know-how of Italian companies in the sector is both high and appreciated, as Simone Raimondi, co-owner of O&G Raimondi, explains. The Varese-based company is an expert in the design, prototyping and customised production of objects in marble, granite and natural stone: "Marble is a very special material to work with,” he says. “Origin, composition, hardness, colour and veining give each block such unique characteristics that only the expert eye of a marble worker can recognise them. By inserting even a slightly incorrect parameter into the machine's program you risk breaking the block, with the obvious associated costs.”
Italy is at the forefront of developing advanced solutions for marble block processing. Exports of Italian-made machines and plant for marble and stone processing generated a turnover of around €780 million in 2018. This figure indicates the very high operating level of the national marble industry, which successfully combines both technology and craftsmanship.
The special nature of marble has long inhibited the technological development of the sector, which relied rather on a craftsmanship approach based solely on experience. However, design evolution and the latest trends in the use of marble for interior architecture are prompting increasingly complex geometries, for which the use of a CNC machine is essential.
There are some very specific problems associated with processing marble. In order to cut this material and prevent the tool from overheating and breaking, it is necessary to use a cooling liquid, usually water. However, the use of water leads to corrosion, making it is necessary to treat machines with special paints that preserve their integrity.
An avant-garde choice
ABM Benelli Macchine is well aware of these special requirements as it goes about designing and building special ‘turnkey’ systems and machines to meet the needs of every customer.
Benelli has always used FANUC controls for its machines. The company had previously supplied Raimondi Marmi with a five-axis milling machine featuring a FANUC 18i-MB5 series numerical control. Released in the early 2000s, the 18i-MB5 was specifically for standard five-axis vertical machining centres. Even then, the CNC was equipped with dynamic cutter compensation and tool length offset.
"Following 11 years of activity, we can confirm that when people say FANUC controls are the most reliable in the world, it’s true," states Alberto Benelli, director of Benelli Macchine.
Given the harsh conditions in which these machines have to work, the chassis structures suffer the wear and tear of time and corrosive agents, but the controls show no signs of degradation.
Today, the sophistication of a marble processing machine is absolutely comparable to the complexity of a machine tool; the requirements are the same in terms of electronics and rigidity, while tool capacity is increasingly high. These factors open up new scenarios for the use of CNCs in this sector.
"Our vision was to create a machine with a simple operating approach," notes Benelli. In fact, the FANUC controls make it possible to switch easily from one type of machining to another while maintaining high speed and managing different numbers of marble blocks. This capability saves time and wastes less material.
While everything worked perfectly from a technological point of view, the market was not mature. "10 years ago, the marble sector was not yet ready for a sophisticated technological solution such as the FANUC controls," explains Benelli. "Talking then about CAD/CAM, high-speed 5-axis machining and centre point was considered pioneering. The requirements were more limited. Raimondi already had an evolved vision that was out of the ordinary for the sector".
On the wave of innovation with FANUC
In recent years, however, the marble sector has been completely transformed. Innovation, advanced technologies and non-standard functionalities have spread, driven by the need to produce pieces and perform processes that, in the past, were not even considered possible in an automated way.
Jeco - this is the name of the machine - is a modern, compact 5-axis CNC machining centre "all in one" that allows roughing, finishing and various engraving operations to be carried out on the same machine, equipped with a FANUC 31i-B5 numerical control.
Valuable assistance
FANUC has an extensive service network all over the world, which is an advantage of strategic importance for machine builders. In Italy, FANUC service centres are able to get machines back up and running within 24 hours of a reported fault. FANUC is also the only company to guarantee the availability of spare parts for 25 years, or at least the repair of a part that has failed.
From a support perspective, Benelli says the presence of FANUC technicians has been constant, both in the design and development phases. By way of example, Raimondi was able to benefit from FANUC assistance for CAD/CAM management (drawing of the part and post processing to create the program).
The machine can be completed with the application of a lathe consisting of a hydraulic tailstock with positioning drive for supporting long work pieces, and a work piece-holding head capable of operating as a C axis for interpolation machining and performing continuous rotations up to a maximum of 500 rpm for removal as a lathe. The machine is equipped with the FANUC 31i-B5 numerical control. Dedicated to 5-axis machining, it can control up to 34 axes (5 simultaneous), 8 spindles and 6 processes; performance is ensured by the internal memory of 8 MB. The most useful functions of the FANUC NC systems are integrated, such as Dual Check Safety for the machine safety standard (2 CPUs communicate with each other and check that the machine is working correctly, if it exceeds the parameters the machine stops and goes to safety), Smart Machine Control, Nano Interpolation / Nano Smoothing / Fine Surface Technology for surface finishing, AI Advanced Preview / AI Contour Control and the management of Macro Executor / C-Executor / FANUC Picture / FOCAS. Jeco features the 10.4'' LCD display with new iHMI interface.
