A nozzle head for descaling rolling stock, said rolling stock moving relative to said nozzle head, is adapted to be mounted for rotation about an axis of rotation relative to a surface of said rolling stock. Said nozzle head comprises a plurality of nozzles adapted to spray a liquid on said rolling stock, wherein said nozzles are positioned at different radial distances from said axis of rotation.

A pickling system for surface treatment, using a pickling medium, of strip steel in the form of standard steel, electric strip, high-grade steel, and extra-high-strength and ultra-high-strength third-generation steel in order to thereby provide a surface suitable for a subsequent shaping process for further processing. The system includes a plurality of treatment tanks connected in series. The pickling system has a modular construction and, starting from the strip infeed, at least one first treatment tank in the form of a dipping bath module is provided in the working direction, downstream of which a plurality of treatment tanks in the form of spray pickling modules are arranged, and at least one final second dipping bath module is arranged downstream of the spray pickling modules.

The invention relates to a steel-plate descaling device, including several steel-plate surface descalers and several steel-plate side-surface descalers disposed along the direction of a flow line as well as a trolley rail disposed in parallel to one side of the flow line. At least one roller-changing vehicle slides back and forth on the rail. The roller-changing vehicle is provided with a roller-changing mechanism. When the roller-changing vehicle slides to a front side of the steel-plate surface descaler, the roller-changing mechanism extends into the inner part of the steel-plate surface descaler to change the roller. The oxide scale of the steel-plate surface is removed physically, having low pollution and high descaling efficiency without a blind spot, and simultaneously having a high degree of automation in replacing the descaling roller through the roller-changing vehicle, saving both time and effort.

A plant for cleaning rolled metal strips provided with a superficial layer of oxide, the plant comprising unwinding means for unwinding at least one coil of rolled strip and pickling means for pickling said rolled strip; wherein there are provided measuring means for measuring the thickness of the superficial layer of oxide, arranged between said unwinding means and said pickling means. A relating cleaning method is also claimed.

A plant for cleaning rolled metal strips provided with a superficial layer of oxide, the plant comprising unwinding means for unwinding at least one coil of rolled strip and pickling means for pickling said rolled strip; wherein there are provided measuring means for measuring the thickness of the superficial layer of oxide, arranged between said unwinding means and said pickling means. A relating cleaning method is also claimed.

A descaling device (2) for chemically descaling a metal strip (4): A spraying device (12, 12a-12d) for spraying a pickling agent (14) onto a top or bottom side (16, 18) of the metal strip (4). The spraying device (12, 12a-12d) has a first outer spraying unit (50) for spraying the pickling agent (14) onto a first edge region (52) of the top/bottom side (16, 18) of the metal strip (4) and a second outer spraying unit (54) for spraying the pickling agent (14) onto a second edge region (56) of the top/bottom side (16, 18) of the metal strip (4), which second edge region lies opposite the first edge region (52). At least one of the two outer spraying units (50, 54) has one or more solid stream nozzles (20), in particular a plurality of rows of solid stream nozzles (20), and/or one or more slotted nozzles (22).

A descaling device (2) for chemically descaling a metal strip (4): A spraying device (12, 12a-12d) for spraying a pickling agent (14) onto a top or bottom side (16, 18) of the metal strip (4). The spraying device (12, 12a-12d) has a first outer spraying unit (50) for spraying the pickling agent (14) onto a first edge region (52) of the top/bottom side (16, 18) of the metal strip (4) and a second outer spraying unit (54) for spraying the pickling agent (14) onto a second edge region (56) of the top/bottom side (16, 18) of the metal strip (4), which second edge region lies opposite the first edge region (52). At least one of the two outer spraying units (50, 54) has one or more solid stream nozzles (20), in particular a plurality of rows of solid stream nozzles (20), and/or one or more slotted nozzles (22).

A combined casting and rolling installation that produces hot-rolled strip with a final thickness<1.2 mm, and includes a first continuous casting installation and a second continuous casting installation, each producing slabs from liquid steel; a slab manipulator that conveys the slabs into a walking beam furnace that conveys the slabs into a rolling installation and heats the slabs to rolling temperature. The rolling installation includes a rough rolling mill forming rough-rolled strips from the heated slabs; a coil box forming a coil from the rough-rolled strip and unwinding the rough-rolled strip; a joining device forming an endless rough-rolled strip by connecting its ends without filler material; a multi-stand finishing rolling mill finish-rolling the endless rough-rolled strip to form a finished strip with the final thickness; a cooling section forming the hot-rolled strip; and a plurality of coiling devices coiling the hot-rolled strip.

A process for forming a descaling composition has the steps of macerating a bone meal with a dimethylamine solution, digesting the macerated bone meal with hydrochloric acid, neutralizing the digested bone meal with calcium oxide, treating the neutralized bone meal with sulfuric acid, and applying a refluxing treatment with dimethylamine and hydrazine hydrate. The process further includes removing the macerated bone meal solids from the dimethylamine solution and transferring the removed solids to an extraction tower prior to the step of digesting. The hydrochloric acid is circulated through the macerated bone meal. The treated bone meal and the sulfuric acid is filtered so as to produce a liquid phase and a solids phase. The liquid phase contains a phosphate amine. The dimethylamine and hydrazine hydrate are added to the liquid phase.

A process for forming a descaling composition has the steps of macerating a bone meal with a dimethylamine solution, digesting the macerated bone meal with hydrochloric acid, neutralizing the digested bone meal with calcium oxide, treating the neutralized bone meal with sulfuric acid, and applying a refluxing treatment with dimethylamine and hydrazine hydrate. The process further includes removing the macerated bone meal solids from the dimethylamine solution and transferring the removed solids to an extraction tower prior to the step of digesting. The hydrochloric acid is circulated through the macerated bone meal. The treated bone meal and the sulfuric acid is filtered so as to produce a liquid phase and a solids phase. The liquid phase contains a phosphate amine. The dimethylamine and hydrazine hydrate are added to the liquid phase.