With a fleet of 17 digitalised and automated machines, the Latécoère 4.0 factory in Montredon is a prime example of a connected workshop in the aerospace industry. Working alongside it, the maintenance department is tasked with eliminating factors that limit productivity and maintenance times. A major priority prior to installation, the maintenance department worked with Technifiltre to recalibrate the extraction and filtration solutions for the highly productive machines.
Bringing together the manufacture of interconnection parts previously processed at the Périole site and new production, the Montredon factory has benefited from resources specific to its objective. With extensive field experience on the equipment already in operation, the six maintenance team members anticipated the move and planned the actions to be taken in order of priority.
Noting the undercapacity of the standard air extraction and filtration systems of the six Mazak 5-axis robotic cells, the team launched an improvement project on this issue. The rapid clogging of the oil mist extraction equipment filters required frequent maintenance. Called in to help on the advice of the machine manufacturer, Technifiltre, the French distributor of LOSMA equipment, proposed adding an easily integrated pre-filter to the Galiléo Losma filtration unit. The Galiléo extraction system combines static and dynamic filtration technologies. The accumulation of stresses from the high-speed chip removal process far exceeded the capabilities of standard equipment: high-pressure water spray in the centre of the tool, spindle speed of 40,000 rpm, chip fragmentation, few machine stops, etc.
The intervention carried out a few months before the move resulted in a reduction in cutting oil consumption, thanks to the dual pre-filtration and coalescence filtration system, as well as improved air treatment by the multi-layer filter, which retains fine particles. In the new factory, the six Mazak centres are operating at 160 hours per week out of a possible 168, with the spindle rotating for more than 80% of the part cycle time. Preventive filter replacement is scheduled every three months. At the old site, several interventions were required during the same period, resulting in lower machine utilisation rates.
Thanks to the experience gained, the maintenance department was better equipped to prepare for the arrival of the large machines. As is often the case, the issues are different. When producing large panels, the rapid movements of the table on a DMU 100 centre generate significant turbulence in the machining chamber. In addition to high extraction rates, it is essential to consider the oil mist collection points. The rapid movements of a workpiece with a ‘significant surface area’ cause a succession of pressure and vacuum surges on both the left and right sides of the table enclosure.
Following the study conducted by Christian Strippoli of Technifiltre, the maintenance department decided to install two Icarus Losma static vacuum cleaners on each machine. They are positioned at both ends of the cell to ensure optimised capture regardless of the sequence of table movements. These powerful devices are capable of absorbing high instantaneous depressions (extraction power up to 1,600 m3/h each).
They have four levels of air filtration. At the entrance to the system, the metal pre-filter stops and recovers micro-chips suspended in the oil mist. Like a ‘quiet chamber’, the pre-filter creates conditions that promote the sedimentation of micro-oil droplets. The deep-bed GREEN coalescing filter (Losma patent) constitutes the second stage of filtration. The F9 filter then filters out any residual micro-mist. Finally, as the filtered air is discharged into the workshop, a HEPA filter (H13) guarantees 99.5% efficiency.
The entire process has been designed so that the machining cell can operate at full spray power, with no restrictions on cutting parameters or material flow rates in high-speed machining. Filter changes are scheduled every six months.
‘Thanks to the measures taken in partnership with Technifiltre, right from the start of the smart factory, the maintenance department is on track to meet its objectives for improving the productivity and reliability of the installations,’ explains Pascal Claude, who closely monitored the configuration of the machine air purification systems. The workshop is operating in line with its objectives. This would not have been possible without optimising the air filtration systems. This has freed up the productivity of the robotic machining cells.
Download the article published in issue 210 of Tramétal