Robotic angular shot blasting: innovation for maximum competitiveness and process information
10. February 2020
About the customer
Surface treatment innovation
Eseki is a company characterised by its three core activities: engineering, installation and innovation. It is a social economy, employee-owned company located in Etxarri-Aranatz (Navarra, Spain). Apart from its installation and maintenance activities, it also specialises in surface treatment: an area in which it provides turnkey solutions, ranging from technology to services.
Indeed, it is in this area where Eseki has made one of the biggest contributions to the industry: the design and commissioning of the first shot blasting robot with 9 angular blasting axes. Flexible and modular, it can be programmed offline in 3D and comes with a smart maintenance feature. With its extensive knowledge of surface treatment processes coupled with its corporate commitment to research and development in robotics, Eseki has become an engineering firm that is capable of designing large automated booths to treat the surfaces of large parts —a particularly attractive possibility for the wind power and iron and steel markets, both nationally and worldwide— while also offering parameterisation services for new parts to be treated, not to mention remote, corrective and preventive maintenance.
To automise a hard and complex process, and get the maximum information
Tratamientos Algoi (Altsasu, Navarra) deals in the surface treatment of parts, particularly specialising in shot blasting, plating and painting. As an Eseki customer for over 25 years, Tratamientos Algoi mainly deals in finishing large parts for the wind power —towers and hubs— and steel industries.
Angular shot blasting is one of the process services it provides. This process is used to clean surfaces whilst micro pitting the part's surface, thus enhancing adherence properties for subsequent treatment and painting stages. “Because this is angular shot blasting, automatic systems don’t work as it is a highly damaging process for equipment. That’s why it’s always done manually: the operator prepares the part and the shot by hand”, explains Esteban Zeberio, the Eseki general manager.
In addition to the hardness of the treatment to which the equipment must be subjected, there is the need for maximum quality. "As the parts involved are used in critical processes —in this case wind power generation— a standard level of finish is required,” adds Esteban Zeberio. Accordingly, the possibility of exercising tight control of the whole process, as well as being able to standardise the blasting and surface finishing process in general, became a real need rather than something to aspire to.
“In this field, current regulations are very clear in relation to how the piece should be worked to prevent its deterioration, for example, but the reality is that the process is carried out by people. An even surface treatment still remains in their hands.”
Moreover, the quality required is particularly demanding when dealing with large parts with complex geometries and a different design and shape: “When working with big parts that considerably vary in terms of geometry, automation becomes more complex. On top of this, if the parts weigh 10, 20, 30 or 50 tonnes, the possibility of having an automated solution is even more complicated.”
Lastly, apart from these process requirements, this is a highly competitive sector, with numerous demands from customers —in TIER 1, TIER 2 and TIER 3 sector segments— as far as cost and time savings are concerned with a view to gaining in competitiveness: "Automating these processes using robotics will be key to improving productivity," says Zeberio.
The first robotic angular shot blasting booth on the market
Eseki's experience in the surface treatment sector was one of the three key factors in designing a robotic shot blasting solution for Tratamientos Algoi. Eseki has spent years specialising in this process and, moreover, it knows the sector very well and is mindful of the competitive demands it is subjected to: they knew that automating was essential.
The second key factor was Eseki’s determined commitment to industrial R&D. Home to a research and development department focused on improving industry surface finishing processes, the first phase of the Tratamientos Algoi project, the one corresponding to prototyping, was funded by a line of credit provided by the Government of Navarra for innovation in industrial processes. Eseki had an attractive technological proposal that responded to a sector need; one that was capable of automating a process that had always been done manually. Moreover, it received support from Tratamientos Algoi to apply the innovation.
Its collaboration with Yaskawa was the third key factor. The possibility of automating the angular shot blasting process was a challenge assessed by both Yaskawa and Eseki on several occasions during the course of their partnership in various projects for the sector. In fact, beyond acting as a technology provider, the Spanish subsidiary of the Japanese company helped design the solution that was finally offered to the customer, as it did in looking for solutions for offline programming.
These three key factors materialised in a first prototype solution that came out of an R&D project funded through the regional government line of support. Upon completion of this phase, Eseki designed a customised booth with a robotic system for Tratamientos Algoi to surface treat wind turbine hubs by shot blasting and a 9-axis CAD / CAM system, which includes a fully automated remote shot blasting and collection system. It was a turnkey project, and Eseki's involvement ranged from the design work to the robotic commissioning of the cabin.
Eseki assigned an engineering team with extensive experience in these types of processes —mechanical and electronic design, a process specialist, computer and electrical experts— while from Algoi’s end, in addition to Operations, company management became directly involved: “A big commitment was required due to the project's demands. Time and considerable resources were invested before any results were seen. The robotics involved represented a big challenge. It was accomplished using CAD/CAM and resulted in a 9-axis control process like this one”, explains Esteban Zeberio.
The automated booth came to life through four phases. The first was the design and engineering, in which the CAD/CAM mechanical and electrical design and communications architecture were defined. The second phase was prototyping: prototype implementation and testing in a controlled environment at Eseki facilities, though still not working with shot. The third phase saw the booth being implemented in an industrial environment with real parts. During this phase the real challenges that the solution had to face were confirmed and resolved: the wear and tear of the booth components, the types of coatings required to protect the installation, the shot blasting paths needed, the distance from which the shot blasting should be applied, the speeds involved, etc. Reengineering was done on the elements that required readjustment. This was followed by the fourth phase, that of the final implementation at the customer's facilities with the first robotic angular shot blasting booth on the market. It was critical at this stage to avoid hindering the Tratamientos Algoi production facility in any way, as they explain at Eseki: “You have an automatic installation to integrate into the global production line. This involves understanding the treatment process as a whole. You have to know the system and adapt robot operations accordingly. Design is not simply confined to the new shot processing cell, but it must encompass the process as a whole.”
Technologically speaking, the solution consists of a 6-axis Yaskawa GP25 robot to which 3 Yaskawa servomotors controlled by the robot's CPU (x, y, z) were added, thereby providing the robot with maximum movement capacity in a frame that was also synchronised by Yaskawa: "The Yaskawa controller had the features required by the 9-axis CAD/CAM we designed," said Esteban Zeberio. The entire process is controlled via a SCADA/HMI. The operator uses a touchscreen to select the part that enters the booth and the one which the process will be applied to.
Results of the installation and customer benefits
Increased productivity, quality and efficiency in consumption: maximum competitiveness
There has been a considerable change at operational level. "beyond our expectations," according to those at Eseki. "Production capacity has risen by 60% to 80% and can go even further than this depending on the arrangement of the cranes and other elements external to the process that takes place in the booth,” they claim. Treatment uniformity has also been improved and with it the quality of the parts. Firstly, due to improvements in the process itself —“the process is carried out at a faster speed and therefore the pitting is better, thus affording greater shot blasting possibilities”—; and secondly, because the process is now automated. Eseki designed an analytical environment capable of monitoring the process to detect existing inefficiencies: “A series of variables were discovered that could be stored, such as the distance at which the process is most effective. We have gained new knowledge that can be applied to the process”. These same analytics are used to plan the preventive maintenance required by the installation.
Another important advantage is that energy consumption is maximised: “The lesser the shot blasting time, the more energy is saved. The task that takes an employee 5 hours to do manually can be done by the robot in the booth in 1 hour 45 minutes.” It also allows for greater production continuity: “There is no need to stop production to incorporate new parts into the line. The programmes are loaded online or using a secured USB, and then a new part with different dimensions and geometry can be incorporated”. To get an idea of how much the process has been simplified, suffice it to say that each hub has up to 10,000 programming points that are worked with SolidWorks in the workshop and which are subsequently loaded onto the system.
Moreover, operator time is maximised: whereas before the piece had to be prepared by a group of operators and then shot blasted by another, now a single operator prepares the part while the robot is working: "Now, operators shot blast more than twice as many parts than they did manually." In this sense, difficulties in terms of recruiting staff have been done away with now that the hard and unhealthy work, which can have serious effects on health if the appropriate measures are not taken, is done by a robot while people can focus on tasks with greater value.
With respect to Eseki's work with Yaskawa, the collaboration proved to be quite well-rounded, both technologically and otherwise. The booth was made possible thanks to the high-performance robot, configured to withstand the aggressive environment, supported by a controller that was capable of managing the CAD/CAM system designed: 9 axes for maximum robot arm mobility with a view to effectively shot blasting parts with complex geometries. According to Esteban Zeberio: “It has not been an easy project. It was difficult to achieve the automation level we needed. Yaskawa has an R&D project that fitted in very well with surface treatment process needs.”
In terms of the human factor, teamwork was crucial: “It was not a simple project. Yaskawa contributed ideas and a highly motivated staff to provide solutions and support throughout the installation. Now that we know the product better, I believe that we can develop many more things”.
As far as the future is concerned, the customer has discovered the possibilities that automation provides and is studying how to go beyond the improvements implemented in the shot blasting booth with Yaskawa technology. Eseki say they are now committed to promoting R&D in plating and then painting. “The solution developed for Tratamientos Algoi can be applied to any sector that requires greater control of treatment processes. Apart from the wind power sector, it may prove to be highly useful for the iron and steel industry”, explains Esteban Zeberio.
Even though there were critical issues from the outset that we were not entirely sure could be overcome —“Will the components withstand the highly destructive environment?; Will maintenance costs versus the benefit of the solution favour the customer?”—, after two years in operation, the major innovation that the solution represents for the process and the sector in general has been confirmed. Yaskawa has proven to be a very robust robot with great durability. “Tratamientos Algoi now has an innovative installation with a very interesting return on investment in production terms thanks to the correct application of robotics. A successful project for the entire industrial sector”, according to Eseki.