Plant for making continuous elastic yarns made of silicone material
A plant for making continuous yarns ( 30 ) made of silicon material comprises at least an extrusion station ( 12 ), into which the material is introduced in an amorphous condition, and extrusion means ( 15 ) which cause the material to exit from the extrusion station ( 12 ) along an extrusion axis (D). The plant also comprises a vulcanization station ( 16 ), located downstream of the extrusion station ( 12 ), at a determinate distance (“L”) therefrom, in which the continuous yarn ( 30 ) is vulcanized in a direction of treatment (T). The plant also comprises a drawing unit ( 18 ), disposed downstream of the vulcanization station ( 16 ).
1. A plant for making continuous elastic yarns made of silicone material, comprising at least an extrusion station, provided with an extrusion body into which said material is able to be introduced in an amorphous condition, and extrusion head able to allow said material to exit from said extrusion station along an extrusion axis, and a vulcanization station comprising a vulcanization oven, located downstream of said extrusion station, at a determinate distance therefrom, wherein:
said extrusion head is disposed so that the extrusion axis is substantially vertical,
said distance varies between 400 and 1500 mm according to the final thickness of the elastic yarn to be obtained;
the plant also comprises a drawing unit, disposed downstream of said vulcanization station, and able to impart on the elastic yarn exiting from the extrusion station, a drawing value in a ratio comprised between 2 and 6 (100-500%), reducing the section of the elastic yarn proportionally, before the elastic yarn enters said vulcanization oven of the vulcanization station, and hence at least along said distance,
and wherein the vulcanization oven is moveable to adjust said distance between said values 400-1500 mm to vary the drawing conditions of the elastic yarn and to obtain a final yarn with a thickness at least less than 0.7 mm, and having the desired orientation of the molecular chains.
2. The plant as in claim 1 , wherein, in said vulcanization station, said extruded product is vulcanized along a processing direction parallel or coincident to the extrusion axis.
3. The plant as in claim 1 , wherein said extrusion body has a vertical elbow shape.
4. The plant as in claim 1 , comprising a collection unit, located downstream of the vulcanization station and able to collect the extruded product, wherein said collection unit comprises said drawing unit.
5. The plant as in claim 4 , comprising a controlled cooling station, located downstream of the vulcanization station and upstream of the collection unit.
6. The plant as in claim 1 , wherein the extrusion station comprises a heating and cooling device for the heat regulation of the extrusion station.