FI56364C - PROCEDURE FOR THE FIELD OF FIBER STRUCTURES - Google Patents

Description

ΓΒΐ m, ANNOUNCEMENTS * U r r q A Δ Ma lbj utläggningsskrift bbioA

• C (45) Patent granted 10 01 1930 IPatent aeddelat * (51) Kv.ik. »/ Int.ci. * C 03 B 37/10 FINLAND - FINLAND (21) - PetenttnaSknlng 7709 ^ (22) Hekemltpllvl —AmBknlngtdag 25.03 .77 '' (23) AlkuplWt — Glltlghettdeg 25.03.77 (41) Has become stuck - Bllvlt offentllg 26.09.78

Pafnttl-) »register board (44) Nthtlvikiipanon j * kuL |

Patant- OCh registerstyrelsen '' Amttkan utlagd och utUkrtfeen publkered 28.09.79 (32) (33) (31) Privilege requested — Begird prlorltet (71) A. Ahlström Osakeyhtiö, Noormarkku, Finland-Finland (FI) (72) Taimo Untamo Loikas , Hamina, Jaakko Tapani Ristola, Karhula,

Suomi-Finland (FI) (5 * 0 Method for breaking up the fibrous structure of mineral fibers - Förfarande för nedbrytning av en av mineralullsfibrer bildad fiber-struktur

In the manufacture of mineral wool products, the pulp obtained by melting generates edge waste on the transport track in connection with cutting the edges of the product. Due to temporary production disruptions, a poor quality product is created, which can be of secondary quality or scrap.

According to current practice, the edge waste is torn into small pieces and pneumatically transferred back to the preform formation site in a suction cabinet. In this method, e.g. if the rupture fails, the piping becomes clogged and causes a production disruption. In addition, the edge waste in the middle of the product impairs the homogeneity of the product. Secondary quality is for sale, but only at a greatly reduced price. Disposal products must be transported to a landfill. When torn, the due to their lightness, the materials are not meltable in oil or gas fired furnaces due to strong gas flows.

It is an object of the present invention to provide a new method by which edge waste, secondary grade and scrap can be ground in such a way that it can be remelted as such or mixed with a raw material or a set of glass chips. This requires sufficient mixing properties to be achieved C 03 B 1/00 2 S b 3 6 4 and a sufficiently high bulk density so that the fibers do not travel with the gas streams of the melting furnace to the outside air.

The method is characterized in that pressing the movable fiber structure between two pressing surfaces, at least one of which is formed by a rotating roll, causes mutual compression of the fibers. The length distribution of the resulting fibers and the average length are determined by the number of fiber crossings in the structure of the article to be fed between the rolls. The advantages of the method are e.g. the simple structure of the device required for its application and the low dust content of the operation.

The invention will now be described in more detail with reference to the accompanying drawing, in which Figure 1 shows an embodiment of the method according to the invention and Figures 2, 3 and 4 show other embodiments of the invention.

In Fig. 1, reference numeral 1 denotes a nonwoven mat which is guided by a feeder not shown in more detail to a fringe formed by rotating press rolls 2 and 3. The lower roll is mounted on fixed bearings and the upper roll is mounted on a lever 4 which allows the flexibility required by the material passing between the rollers. The compressive force of the rollers is provided by a pneumatic or hydraulic cylinder 5. The crushed fibrous material 6 falls into a trough 7, from where it is conveyed, not shown in more detail, to a furnace for remelting. Both opposite rollers can be equipped with a drive or alternatively only one. The material of the rollers is steel, rubber, plastic or another material resistant to compression and wear. The diameter of the rollers is determined by the thickness requirement set by the thickness of the material to be fed; the roll diameters typical of standard products are 50 ... 600 mm. The length of the rollers is selected according to the width of the material to be fed.

In Fig. 2, the fibrous structure is pressed between two endless steel belts 12, 13 running around the turning rollers 8, 9 and 10, 11. The belts are supported in the part between the turning rollers by means of support rollers 14, 15.

Claims (4)

A method for breaking a fibrous structure formed of crisscrossing mineral fibers into a remeltable form, characterized in that pressing the movable fibrous structure between two pressing surfaces, at least one of which is formed by a rotating roll. resulting in a dense fibrous flour. Method according to Claim 1, characterized in that the fibrous structure is pressed between two rotating rollers. A method according to claim 1, characterized in that the fibrous structure is compressed between a rotating roll and a fixed plane. 56364 In Fig. 3, the material is compressed between a rotating roll 16 and a fixed plane 17. In Figure 4, the fibrous material is passed through two successive pressing points 18 and 19 formed by a pair of rollers. The following is an experiment performed with the device according to Fig. 1: Diameter of press rolls 200 mm Length of press rolls 150 mm Compressive force 2.5 t to the gap between the rollers, where the fibrous structure was crushed and a powdery mass was formed. The length distribution of the fibers before compression was 1 ... 30 mm and after compression 1 ... 150 μm. The bulk density of the fibrous flour pulp was 800 kg / m 2, while the bulk density of the raw material mixture is about 1500 kg / m 2. A method according to claim 1, characterized in that the fibrous structure is pressed between two belts running around the rollers.