ROLLER HEARTH FURNACE

Abstract

A roller hearth furnace, in particular a tunnel furnace of a thin-slabbing plant, including multiple cooled furnace rollers arranged in a mutually spaced manner in the transport direction in order to transport a strip or a slab have a number of support rings on a rotatably mounted axle and are formed with an insulation in the axial region between two adjacent support rings and adjacently to the respective outer support rings. The insulation is a highly insulating fiber material. Scale funnels are arranged below the furnace rollers. Scale barriers that extend transversely to the transport direction in the manner of the furnace rollers are provided in the free areas between each two successive furnace rollers in the transport direction.

Claims

1-4. (canceled)

5. A roller hearth furnace, comprising: a plurality of cooled furnace rollers arranged at a spacing from one another in a transporting direction for the transport of a strip or of a slab, said rollers having a plurality of support rings on a rotatably mounted axle and being provided with insulation composed of a highly insulating fiber material axially adjacent to at least one of the support rings; scale funnels arranged below the furnace rollers; and, scale barriers provided in free spaces between in each case two successive of the furnace rollers in the transporting direction, the scale barriers being arranged to extend transversely with respect to the transporting direction in a manner similar to the furnace rollers.

6. The roller hearth furnace according to claim 5, wherein the scale barriers are bar-shaped and are composed of a heat-resistant material.

7. The roller hearth furnace according to claim 5, wherein the scale funnels have funnel walls, wherein the scale barriers are arranged on the funnel walls and/or in a self-supporting manner above the scale funnels.

8. The roller hearth furnace according to claim 5, wherein the scale barriers terminate slightly below a transport plane of the furnace rollers so as not to contact the transported material.

9. The roller hearth furnace according to claim 5, wherein the roller hearth furnace is a tunnel furnace of a thin slab plant.

Description

[0015] Further features and details of the invention emerge from the patent claims and the following description of an exemplary embodiment which is illustrated in the drawing.

[0016] The single FIGURE shows a schematic illustration of an arrangement of cooled furnace rollers 1 which are provided in a roller hearth furnace or tunnel furnace (not illustrated). The furnace rollers 1 transport a material to be heat-treated, for example a strip or a slab, through the roller hearth furnace or tunnel furnace in a transporting direction T.

[0017] In detail, the furnace rollers 1 are configured in the manner known per se from WO 2018/059940 A1, that is to say their carrying axle is provided with thermal insulation composed of a fiber material or a fiber wool.

[0018] Scale funnels 2, which are bounded by funnel walls 3 composed of a refractory material, are provided below the furnace rollers 1.

[0019] Scale barriers 4 of bar-shaped configuration which extend transversely with respect to the transporting direction T are provided in the free spaces between the furnace rollers 1. Here, the scale barriers 4 are, on the one hand, arranged on the funnel walls 3 and, on the other hand, provided in a self-supporting manner, that is to say with a fastening at each of their bar ends, above the scale funnels 2, wherein the scale barriers 4 terminate slightly below the transport plane 5 of the furnace rollers 1 so as not to contact the transported material to be heat-treated, such that there is only a very small vertical gap between the transport plane 5 and the upper edges scale barriers 4.

[0020] The scale barriers 4 are manufactured from steel or a refractory material or cast in the form of a molding.

[0021] During the transport of the material to be heat-treated through the roller hearth furnace or tunnel furnace by means of the furnace rollers 1, scale detaches from the material to be heat-treated and then flies around in the vicinity of the furnace rollers 1 and attacks or destroys the insulation of the furnace rollers 1, said insulation being composed of fiber material or fiber wool.

[0022] This is prevented by way of the scale barriers 4 because the flying scale or scale particles is/are intercepted by the scale barriers 4 and diverted into the scale funnel 2 lying therebelow in each case, such that the scale is effectively kept away from the furnace rollers 1 lying in each case next to the scale barriers 4.

[0023] The diverting of the scale or scale particles into the scale funnels 2 by way of the scale barriers 4 is furthermore assisted by virtue of the fact that the bar-shaped scale barriers 4 are configured, on their longitudinal sides extending transversely with respect to the transporting direction T, with oblique surfaces which taper downwardly in a conical manner toward the scale funnels 2.

[0024] The scale accumulated in the scale funnels 2 can be disposed of via scale doors 6 which are provided in each case at the lower end of the scale funnels 2.

LIST OF REFERENCE DESIGNATIONS

[0025] 1 Furnace roller [0026] 2 Scale funnel [0027] 3 Funnel walls [0028] 4 Scale barrier [0029] 5 Transport plane [0030] 6 Scale door [0031] T Transporting direction