The importance of the granite sector in the Galician economy is fundamental. The Galician granite industry is the 2nd most important in Europe (after Italy) and the 5th in the world, appearing ahead of powers such as Belgium, Portugal or Germany.
In this context, the DIAMANTE project represents an opportunity for Galicia to increase production and improve the competitive situation of the natural stone production sector, after years of relocation to countries with lower labor costs, thanks to an innovative control system developed for multiwire granite block cutting machines. Specifically, DIAMANTE proposes the development of a solution that is capable of analyzing the reality of the cutting process thanks to the implementation of advanced sensing and control systems, under the paradigm of Industry 4.0.
The objective of DIAMANTE is the improvement of the main factors that affect the process, which in this case are the consumption of diamond wire (main cost factor of consumables) and the inherent costs of multiwire machines in breakdown stops and unforeseen failures. As an example, a company that has a monthly production of about 45,000 m2 of laminated granite, loses about € 150,000 for each day of downtime. As for the cost of the diamond wire, it can represent about 40-50k € / month.
Therefore, DIAMANTE proposes a solution based on the industry 4.0 paradigm, which allows greater control of all the parameters of the cutting machines, which will imply an improvement in production, a reduction in waste that will transform the process into a more environmentally friendly one, with an increase in the added value of the product and an improvement in production costs.
During the last 2020 annuity of the project, actions have been carried out for the sensorization and control of the cutting wire. These activities have focused on the installation of artificial vision cameras, together with modifications to the cutting thread to facilitate its correct detection, and the installation of different optical sensors and accelerometers, all with the aim of performing predictive maintenance of the DIAMOND cutting machine during the cutting process of different granite qualities.
With the installation of these sensors and the relevant modifications in the thread, it is intended to control different important points both for the control of the correct stone cutting and for the correct operation of the thread, being able to measure and report key parameters during the cutting process, such as rotation, speed or thread wear.
Another line of work has consisted in measuring the size of the bead to determine when it can be replaced, measuring the wear between the moment of the beginning of its life cycle and when it approaches its end, being able to observe during the process a decrease in its width.
Another key point throughout this last annuity in the control of both the correct cutting process and predictive maintenance, has been the analysis of vibrations that occur in the motor drum that produces the rotation of the threads. These vibrations increase their frequency the greater the wear of the thread or when there is a problem in the cutting of the stone itself, since any possible problem is transferred to the motor drum and this factor causes vibrations.
The image shows the increase in vibrations as time passes. In green the vibrations that occur on the first day of the thread’s life are shown, in yellow its vibration is shown at 2 weeks of life and in red in its third week of its life cycle.
Finally, mention that the integration of the different partial developments has been carried out in the demonstrator installed in GRANISA. More specifically, this has entailed the integration of artificial vision systems, acquisition systems and hardware architecture control and processing. Likewise, the final validation phase has entailed the corresponding tests in relevant environment and the analysis of pre-industrial implementation.
To achieve the above objectives, the Galician companies of the DIAMOND consortium cover the entire value chain of project activities and have formed a multidisciplinary group with the complementary know-how necessary for the correct execution of the same:
NODOSAFER, the leading company of the project, is an international reference entity in the manufacture of industrial stone cutting machines and its equipment is one of those that obtain a better performance of cutting wire. It should be noted that NODOSAFER has extensive experience in R& D projects related to its products.
SYSPRO is an engineering company focused on the integration of technologies in the field of automation, industrial software, robotics, artificial vision and advanced sensorization and that has made a qualitative leap in recent years in R& D initiatives.
WDIAMANT is a company that develops diamond cutting wire for the natural stone sector, with extensive experience in R& D projects related to its products, established in the world market and with a high volume of exports.
GRANISA is the ultimate end user and receiver of the technology developed in DIAMANTE. It is the 5th company in added value of the sector in Galicia. He has contributed his experience in the transformation of granite and has implemented the solutions in a real environment to perform pre-industrial validation.
With the aim of promoting innovative activity within companies, strengthening their international leadership capacity, improving their competitive position and complementing the developments of the project, the consortium has had the support of the AIMEN Technology Center, an entity with proven experience in artificial vision activities, monitoring, industrial control and advanced data processing.
The DIAMANTE project, framed in the CONECTAPEME 2018 program, is financed by the Xunta de Galicia through the Galician Innovation Agency (GAIN) and the support of the Ministry of Economy, Employment and Industry and is co-financed from ERDF Funds within the framework of axis 1 of the Erdf Galicia operational program 2014-2020.