The logical Consequence

Perini Journal

This is the start of a process of evolutionary innovation aiming at attaining increasingly higher production, quality and flexibility levels of rewinders; this process strongly accelerates the development of surface winding systems.

This is how the Fabio Perini S.p.A leadership was born, on the basis of a technology that was later to become the standard in the rolls converting industry.

IN 1993, FABIO PERINI S.P.A PRESENTS THE SINCRO TRANSFER SYSTEM, extreme sythesis of 20 years of experience in surface winding. More than the normal evolution of an already-tested technology, the Sincro system is a veritable innovation, whose main nucleus is the transfer system: the transfer is positive and is performed without the need for a vacuum roll or cutting blade. Pick-up is facilitated by the rotation of the Sincro roll, which brings the web closer to the core that is to start the new log; winding rolls cannot get dirty any longer thanks to the fact that, after receiving the glue, the core is wound by the web.

Transfer precision is absolute and production speed maximised.

These are Sincro’s advantages:

• High production speed, especially as for number of transfers, potentially superior to the fastest rewinders available on the market;

• Perfect transfer;

• Simpler operation, thanks to the extensive use of electronics;

• Extreme reduction of maintenance and relative costs;

• Winding quality enhancement;

• Utmost flexibility, owing to the use of electronics;

• Reel width optimisation;

• Compatibility with the coreless winding system (Solid).

FROM 1993, THE DEVELOPMENT OF THE SINCRO LINE HAS FOLLOWED TWO DIRECTIONS. The first is a process of continuous enhancement of a revolutionary machine, for a full expression of its potentialities. The second direction consists in the research for efficiency maximisation (meant as the relationship between theoretical and actual production) of the entire converting line considered as an integrated, reliable and flexible production system, of which the rewinder is the key element.

A LAYMAN’S REFLECTION. The science of economics, and especially the theory of consumption, has coined a useful expression to denote extreme behaviours that somehow turn out to find a balance: corner solutions. The corner solutions are, as aforementioned, extreme conducts resulting from peculiar preferences, much more diffused than we can expect.

Having elaborated and developed a technology proprietary of the Sincro quality and flexibility, in the late ‘90s the company found itself in the condition of searching exclusively for corner solutions to further evolve its product range.

The first direction led to the development of the XXL, a rewinding line of huge dimensions, for production lines with “extreme” characteristics. This endeavour met with great success: three XXL lines have already been installed worldwide to date, notwithstanding the noticeable investment required.

But this was not the only possible way. The other was attempting a new revolution: a non-conventional solution.

CHOICES AND RENUNCIATIONS. As often happens, also in mechanical design each choice may entail a renunciation.

Having developed and enhanced it for 30 years, Fabio Perini S.p.A. knows very well the advantages of the surface winding system. On the other hand, also the potential development limits are well known as well as the advantages that the central winding system offers under certain conditions.

Choosing one of the two technologies necessarily entails renouncing the advantages offered by the other.

The company’s aim was indeed that of overcoming this dichotomy, i.e., conceiving a machine able to combine the advantages of the two winding systems. And the reason for this was not mere engineering pride or technological passion. Rather, the aim was a versatile, reliable and fast winding system that could constitute the core of a completely automated line, even in the most delicate and complex phases, without any restrictions on the paper type to be used and the “density” of the rolls produced.

This need comes from the requirements of two market segments: the companies aiming at offering a wide range of products, extremely diversified for paper kind and roll density; the companies that produce a smaller range of products, with characteristics that cannot be fully managed, in non-extreme conditions, by Sincro technology lines. Many companies operating in the North American area, producing the so-called “extra-soft” rolls, belong to the second segment.

THE LOGICAL CONSEQUENCE. In order to guarantee the utmost flexibility in the definition of the final product characteristics, the design solution was a more precise winding control. But this could not be attained to the detriment of speed and safety.

From the mechanical point of view, it was decided to keep the angular velocity homogeneous in every point of the roll, even in “extra-soft” rolls rewinding, thus obtaining a better control over density uniformity and a noticeable reduction of vibrations.

From the design point of view, the answer is very simple. If surface winding is controlled by three rolls, among which the log takes shape, increasing the number of control points will be sufficient. It seems quite simple: you only have to combine the two winding technologies in use and co-ordinate their operation. This way, another, central control point is added to the three points of the surface winding. Logical, isn’t it?

The problem is how to do it. With respect to the traditional surface winding machines, the number of control parameters is higher and so a complete algebrical re-formulation of the machine is necessary.

In order to add a central log “tutor”, this must follow a well-defined and repeatable path in the rewinder, preferably straight line.

Finally, the need to keep speed and web tension constant (and adjustable) requires absolute precision in the co-ordination of a high number of electrical drives, on the basis of the detection of the position of the winding control elements.

Today, at Fabio Perini S.p.A., this seems attained.

TIME: AN EPOCH-MAKING TURNING POINT. The result of this technological effort is the TIME rewinder, part of a complete and fully automated converting system. In the TIME system, the rewinder guarantees an almost complete control over the whole winding cycle, through the interaction of the three surface control rolls - whose geometry has been modified - with a couple of pneumatic axial “tutors”. These are introduced in the roll core, phasing their rotating speed and position with those acquired by the roll, then expand and put the roll in axial tension, accompanying it to the machine exit. The addition of this element allows to manage rotation speed and web tension, conferring safety and quality to rewinding.

Through the control of rotation speed combined with the control on log circumference by surface rolls, it is possible to attain rolls with a wide range of characteristics and, most of all, it is possible to produce the so-called “extra-soft”, low-density rolls, without effecting product quality and production speed.

But TIME is more than this. For the first time in the history of converting, such a performing rewinder has been associated with an automatic unwinder, able to change the reel while the machine is running, without varying the tension of the web feeding the rewinder.

The automation of the unwinder allows, with the machine in production, to always have a new reel available in standby position, ready to be started before the reel in production is spent. This process guarantees continuous feeding of the rewinder without any manual intervention nor machine downtime.

A COMPARISON IN EXCELLENCE. The epoch-making turning point represented by TIME is not only technological but also strategic. For Fabio Perini S.p.A., this process does not represent replacement of the Sincro technology, rather a completion or an alternative.

TIME is not born to replace Sincro, which is still requested and widely used, but to “collaborate” with it and complete the control during all winding phases, thus satisfying the needs of different companies, lines of business and markets.

TIME is a technology aiming at guaranteeing:

• Utmost flexibility in defining product characteristics;

• Maximum equipment automation;

• Extreme versatility in the choice of raw materials;

• Utmost product quality, even in extreme conditions.

In conclusion, not a technology for everyone, but a forced choice for the companies who feel the need to answer an extremely diversified and ever-evolving market demand.

THIS IS ALSO THE CASE OF AN EPOCH-MAKING TURNING POINT: before TIME, technological development was always aimed at the system’s maximum enhancement, to reach economical efficiency and improve return-on-investment.

With TIME, technology and automation favour the utmost flexibility in the definition of product characteristics, in the choice of raw materials used and in the change of product, all the while maintaining or actually improving the overall efficiency of the production process.

With TIME, technology no longer defines limits, but rather establishes new degrees of freedom. •