SE463080B - DEVICE FOR HEATING THE ELECTION SUBSTANCES - Google Patents

Description

15 20 25 30 ae "nan H. Due to the lower temperature and the higher roller pressure, the rollers wear unnecessarily fast. 5. Due to the higher roller pressure and higher speed, higher installed engine power is required.

The device according to the invention constitutes a solution to these and other related problems and is characterized in that at the portions of the roll blanks which in the fuel-fired furnace rest against rails or beams, suitably water-cooled, induction coils are arranged at each such portion for heating the respective previously not fully heated portion of the roll blanks, which coils can be raised and lowered. By means of this device it is thus possible to completely avoid the rail marks in the billet during all or parts of the rolling process.

The height and lowerability of the coils also means that they can either be raised to close abutment and efficient heating of the rail marks or lowered to allow transport along the runway of the roll blanks without risk of injury.

The invention is further exemplified in the accompanying figures, of which figure 1 shows a layout for a plant according to the invention, and figures 2-H various examples of embodiments of the induction coils.

Figure 1 shows at 17 a fuel-fired furnace, in which roll blanks 8 are heated, resting on rails or beams 9, suitably water-cooled. The portions of the blanks 8 which rest against the rails 9 are not fully heated, and the above-mentioned rail marks occur. When a blank leaves the oven (arrow 10), for example to the left in Figure 1, the blank is placed in such a position that each rail mark will lie directly over an induction coil 12. The induction coil is energized and induces a current in the rail mark which is heated. When the rail mark has reached the same temperature as the nominal temperature of the rolling stock, the heating is interrupted.

The result is that the above-mentioned inconveniences during rolling are eliminated, which will thus provide a simpler rolling procedure. In addition, a not insignificant economic return in the form of improved quality of the rolled end product, increased production, less roll wear and lower engine power.

After the heating, the blanks 8 (arrow 11) are moved to the rolling mill 13, suitably along a roller conveyor. 10 15 20 '25 085 -r lï-oš The induction coil (s) 12 are arranged after the discharge point for the billet from the fuel-fired furnace 17, anywhere after the discharge point, even after the first pair of rollers 13.

Figure 2 shows an induction coil of copper 1, drawn around a sheet metal package 2. 3 is a protective cover and U a refractory protection. 5 is a frame with the possibility of raising and lowering the coil 1. The roll blank is shown at 6 and 7 is a portion cooled by rails or beams in the oven with rail marks, which portion is meant to be heated by means of the induction coil 1. A number of coils can be used, one for each rail mark (see Figure 1).

The coil 1 is placed in the system according to one of the following alternatives: a) In the immediate vicinity of the outlet for the fuel-fired furnace 17. b) Between rollers in the roller path (path) from the furnace to the rolling mill 13. c) As a separate heating station next to, behind or in front of the oven 17.

The induction coil (s) 12 are fed at a frequency so adapted that the induced current receives a penetration into the material which corresponds to the depth of the cooled substance.

Figure 3 shows an alternative which differs from figure 2 in that the coil is partly arranged as a flat coil 15 with a part 1Ä running next to the blank.

See especially the cross section.

Figure H shows an alternative with a clean flat coil 16 lying on a sheet metal package 2.

In connection with the coils, temperature measuring means (not shown) can be arranged for controlling the current to the coils and thus the induction heating to substantially the same temperature in the whole blank.

The devices according to the above can be varied in many ways within the scope of the following claims.

Claims (5)

f "(h 4oo G00 PATENT REQUIREMENTS Device for heating rolling stock, arranged at or in connection with a fuel-fired furnace or rolling process, characterized in that at the portions of the rolling stock (8) which rest in the fuel-fired furnace (17) against rails or beams (9), suitably water-cooled, Induction coils (1) are arranged at each such portion for heating respective previously not fully heated portions of the roll blanks (7), which coils (1) can be raised and lowered. Device according to claim 1, characterized in that the induction coils or coil (12) are arranged after the discharge point for the roll blanks from the fuel-fired furnace (17), possibly after the first pair of rollers, whereby full heating can be carried out. 3. Device according to claim 2, characterized in that in connection with the coil (s) temperature measuring means are arranged for controlling the induction heating to substantially the same temperature in the whole blank. Device according to one or more of the preceding claims, characterized in that the coil or coils (12) are arranged below the blanks and their rail marks (7) after the discharge from the oven. Device according to one or more of the preceding claims, characterized in that the induction coil (s) (12) are arranged to be fed at a frequency so adapted that the induced current receives an penetration into the material which corresponds to the depth of the cooled substance.