Method and device for in-line surface treatment of slabs

Method for improving the outer surface quality by an in-line outer surface treatment of slabs (5), which are produced in a continuous process from strand casting to hot rolling, for example pursuant to the CSP-process with a heating furnace (3) arranged between the CSP-casting machine (2) and the hot rolling train (4), wherein a defined surface of the slab (5) with a layer thickness per slab side of up to 4 mm is oxidized in a targeted manner by an oxidizing flame or an oxidizing gas mixture applied to the upper and lower sides of the slab (5) by means of an oxidation device (21) containing nozzles or nozzle-like devices;

• the oxidation product on the slab surface can be solid or liquid, wherein the oxidation treatment of the slab surface with an oxidizing flame or with an oxidizing gas mixture is combined with the following processing in-line method steps:
• prior to the oxidation treatment the outer surface of the slab is freed of naturally occurring scale by a low pressure or high pressure scale washer (22),
• after the oxidation treatment the created oxidation layer as well as the newly formed scale is cooled by water cooling nozzles (23) or other appropriate media or tasks, mechanically broken up in a roll pair (8) and removed from the surface of the slab by a low pressure scale washer (9) or a conventional high pressure scale washer (10).