SHEET MATERIAL COLD WORKING AND CUTTING LINE

The present invention relates to a sheet material cold working and cutting line. More specifically, the invention concerns a working line of the above kind permitting working at the same time on two parallel sheets, supplied from two bobbins, thus carrying out a contemporaneous double working and cutting.

As it is well known, baskets are realised since many years to be used for power production systems by thermal exchange between smokes and liquids, and particularly to be used for recovery of smoke heat and the purification of the same smokes.

Said baskets, that can be assembled in various ways, are realised by an overlapping of shaped sheets (pairs of two sheets, and so on until filling the whole basket), on which different arrangement are realised, said arrangements, when juxtaposed, realising a suitable flow path for smokes.

Baskets are realised providing the superimposition of double working sheets with plain sheets. Particularly, double working sheet plates have a kind of undulation, with a substantially diagonal run, and a plate corrugation.

These double working sheets are interposed with flat sheets, in order to obtain the final optimum result of heat recovery and/or smoke purification. Usually, systems are provided with a line realising the undulation first and then the corrugation of the sheet, and then measure cuts the sheets, and after juxtaposes within the basket the plates with the plain sheets, cut with the same measure.

By a patent application filed on even date by the same Applicant, a solution has been suggested for realising a roll permitting realising, by a single cold working, said double shaping plates.

Now, the Applicant suggests a cold working and cutting line permitting working on two parallel sheet supply bobbins, and then carrying out a parallel cutting of the same. Another object of the present invention is that of providing a working line of the above kind permitting working a sheet bobbin by a roll only applying an undulation on the sheet, and a roll by which both

undulation and corrugation are realised on the sheet, in order to be able to cut then the two sheets so worked.

As an alternative, it is possible working an undulated sheet and a plain sheet, which advance in parallel and are cut together. Advantages obtained by the solution according to the present invention as far as manufacturing costs, and manufacturing rate, are well evident to all those expert in the field.

It is therefore specific object of the present invention a sheet material cold working and cutting line comprising a first and a second bobbin sheet material supply lines, a shaping head provided wit a shaping roll, provided in said first supply line, cutting means, provided at the outlet of said first and second supply lines, downward said shaping roll, and parallel driving and control means for said first and second supply lines, and operation means for said cutting means. Preferably, according to the invention, said shaping roll is a roll provided with a surface shaping suitable to realise at the same time an undulation and a corrugation of the sheet material.

Always according to the invention, said shaping roll can be replaced by another shaping roll. Furthermore, according to the invention, said driving means permit the adjustment of the length and/or speed of the sheet to be subjected to working before cutting.

Still according to the invention, said cutting means can be comprised of a guillotine like shear. Furthermore, sheet-sliding means can be provided downward said cutting means.

The present invention will be now described, for illustrative but not limitative purposes, according to its preferred embodiments, with particular reference to the figures of the enclosed drawings, wherein: figure 1 is a perspective front view of a sheet material cold working and cutting line; and figure 2 is a perspective rear view of a sheet material cold working and cutting line.

Observing the figures of the enclosed drawings, it is shown an embodiment of the sheet material cold working and cutting line according to the invention, generically indicated by reference number 1, permitting

the working of sheets supplied from bobbins 2, 3, which can have, for example a maximum thickness of 1.5 mm and a wideness of 800 mm.

Particularly, said cutting line can be used for realising sheets for filling cold and intermediate layer baskets for Ljungstrom pre-heaters. Line 1 according to the invention allows carrying out three functions at the same time, namely:

- contemporaneous cut of two sheets ready to inserted within the basket;

- pre-shaping of one of the two sheets; - programming of each cut with a length increase by suitable control board, in order to cut sheets having different length conforming to the trapezoidal shape of the baskets, so that each pair of sheets (straight and undulated) will have a growing measure.

As already said, working line 1 according to the invention provides two unwinding reels 4, 5, provided in parallel, on which bobbins 2, 3 having the same thickness, wideness and weight are mounted.

Sheets 2, 3 are unwound and introduced, respectively, one (3) within a fret - shaping head, generically indicated by reference number 6, shaping the sheet 3 according to the specific undulation required, and one (2) is directly supplied to the cutting device 7.

Since shapings are different each other, ranging between 10 and 20 different shapes, fret - shaping head 5 can be disassembled and replaced, according to the shaping to be realised.

The other plain sheet 2 is introduced within a dragging roll pair 8.

As already said, it is provided a control board, generically indicated by reference number 9, permitting programming the cutting length of the two sheets 2, 3 and also programming the sheet 2, 3 advancement rate. Fret - shaped sheet 3 and plain sheet 2 have the same advancement speed.

Fret - shaped sheet 3 and plain sheet 2 pass then under the cutting device 7, comprised of a guillotine like shear, continue their path along suitable guides 10, until when distance between shear 7 and the end of said sheet has the set length. A relay (not shown) controls the cut

of the shear 7, allowing obtaining at the same time a plain sheet and a shaped sheet.

Line continues its work until reaching the number of programmed shots, ranging between 12 and 48. The present invention has been described for illustrative but not limitative purposes, according to its preferred embodiments, but it is to be understood that modifications and/or changes can be introduced by those skilled in the art without departing from the relevant scope as defined in the enclosed claims.