The mechanised cryogenic allows to guarantee the hygiene of the pieces of the aeronautical sector component manufacturing sector component manufacturing sector

The mechanised cryogenic consists in employing a gas refrigerante in the process of mechanised. CIC marGUNE, Centre of Cooperative Investigation of Manufacture of High Performance, coordinates a line of investigation of the mechanised cryogenic, where participate the UPV/EHU, Tecnalia and the University of Mondragón. The aim of the line of investigation is to guarantee a process of clean manufacture, and besides, contribute to the hygiene of the pieces of the aeronautical sector component manufacturing sector component manufacturing sector.

The mechanised is a process of manufacture of pieces by means of the elimination of material by start of shaving. The fluids of cutting that use in the majority of the operations of mechanised by start of shaving have two aims: on the one hand, lubricate the zone of cut, and on the other hand, refrigerate, that is to say, delete the heat produced in the zone of cut not to affect to the surface mechanised. But said flowed are harmful for the environingingment and for the people —there is some one hundred illnesses associated to this type of lubricante—.

To solve the problems that present the methods of mechanised conventional, one of the main alternative that is investigating at present is the mechanised cryogenic. An innovative method to refrigerate the tool of cutting and the critical points of the piece during the mechanised, thanks to the employment of a gas refrigerante very cold, that can be liquid nitrogen or CO₂.

So much the liquid nitrogen like the CO2 are basic and cheap products, but besides, “the CO₂ can apply of external way in an already existent machine, without need to realise any modification in said machine, with the investment that this supposes”, account Franck Girot, coordinator of the line of investigation of CIC marGUNE. There is already proofs that the technology works, and therefore treats of a line of investigation directly related with our companies, and that it can arrive to the market in brief.

At present is working with pieces of hygiene for the aeronautical sector component manufacturing sector component manufacturing sector, automotive sector, railway industry, etc. Sectors in which the pieces or the components that mechanise have to have some quality and, especially, do not have to present superficial damages, since generally a break of piece generates because of superficial defects. Thus, “for this type of applications the mechanised cryogenic is a guarantee of face to avoid said defects” signals Girot. “It treats of an increasingly controlled subject especially in the aeronautical sector component manufacturing sector component manufacturing sector” adds. Each piece realised has a specific follow-up to know in which conditions has realised the mechanised and, at the same time, guarantee that said piece in his cycle of life does not go break because of superficial defects.

Girot Stands out that, in comparison with the systems of mechanised conventional, the refrigeration of the sharp region, that experiences the highest temperature during the process, avoids changes in the microstructure of the tool. This self-evident in improvements, often remarkable, in some provision of the materials, standing out, between others, the increase of the life of the pieces until a 50 or 100 %, the resistance to the wear, the life to fatigue, etc.

Besides, “is a totally respectful process with the environingingment, since during his realisation does not generate any type of poured or residue”, signals Girot. The cryogenic gases obtain of other processes, therefore, is a second use of gases, that if no, had to delete without greater profit. During the mechanised of the pieces the fluid evaporates quickly and goes back of natural form to the atmosphere. The piece remains entirely clean of impregnaciones of fluids of cutting and does not generate any residue that contaminate the machine tool, the shavings or the place of work. This represents an important economic improvement.

The system can work to speeds more elevated that with machines of mechanised conventional. Therefore, it increases the productivity and achieves a work of greater quality, what translates in a reduction of the costs of obtaining of the pieces.