Abstract

A plant and process for the continuous production of hot-rolled steel strips with a minimum thickness of 0.3 mm is disclosed which includes a continuous casting device of thin or medium slabs with a thickness between 40 and 150 mm and a maximum width of at least 2100 mm followed by a roughing mill, a first induction furnace, a water descaler, a second induction furnace, a finishing mill, a cooling station, a cutting station and a winding station. A system for feeding a protective atmosphere containing ≤3% vol. oxygen is provided from the inlet of the second induction furnace to at least the third stand of the finishing mill. Between the continuous casting device and the roughing mill, an initial thermal conditioning and descaling section is provided having in sequence an induction edge heater, an induction heater for the rest of the slab surface and a water descaler.

IPC Classes  ?

• B21B 1/46 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-sectionSequence of operations in milling trainsLayout of rolling-mill plant, e.g. grouping of standsSuccession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting
• B21B 45/00 - Devices for surface treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills

Abstract

Plant and process for the continuous production of hot-rolled steel strips with a minimum thickness of 0,3 mm, comprising a continuous casting device (1) of thin or medium slabs with a thickness between 40 and 150 mm and a maximum width of at least 2100 mm followed by a roughing mill (2), a first induction furnace, a water descaler, a second induction furnace, a finishing mill, a cooling station, a cutting station and a winding station, a system for feeding a protective atmosphere containing ≤3% vol. of oxygen being provided at least from the inlet of the second induction furnace to the third stand of the finishing mill, and further comprising, between the continuous casting device (1) and the roughing mill (2), an initial thermal conditioning and descaling section (4) comprising in sequence an induction edge heater (4.1), an induction heater (4.2) for the rest of the slab surface and a water descaler (5).

IPC Classes  ?

• B21B 45/00 - Devices for surface treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
• B21B 45/04 - Devices for surface treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for de-scaling
• B21B 1/46 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-sectionSequence of operations in milling trainsLayout of rolling-mill plant, e.g. grouping of standsSuccession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting

Abstract

Mill rolls capable of rolling long kilometers used for ESP production line and a method for rolling long kilometers using the mill rolls. The mill rolls include rolls (3, 4), a bearing box (2) and a roll shifting hydraulic cylinder (1), wherein the middle portion of the surface of the roll sinks inwards, one end of the rolls is frustum-shaped, smaller and smaller outwards, so that the roll surface forms a compensation ramp, and the other end of the rolls is cylindrical. The upper roll (3) and the lower roll (4) have the same roll profile and are positioned in the opposite direction. The mill rolls are characterized by reduced runaway of the rolled product and a longer service life.

IPC Classes  ?

• B21B 27/02 - Shape or construction of rolls
• B21B 1/46 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-sectionSequence of operations in milling trainsLayout of rolling-mill plant, e.g. grouping of standsSuccession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting

Abstract

A plant for the endless or batch production of strips and plates of hot-rolled steel, with thickness from 0,6 mm to 50 mm, comprises a continuous caster (1) of thin slabs with liquid core reduction, followed by an induction heater (2), with a first shear (3) therebetween, and then a rolling mill (4) followed by a second shear (5) and a run out table with a cooling device (6) and a pusher/piler (7) for plates and then a third shear (8) and a plurality of coilers (9), and it further includes a minimum-reduction rolling stand (10) arranged between the continuous caster (1) and the first shear (3), said minimum- reduction rolling stand (10) being designed to perform a slab thickness reduction of only about 10% and in any case not more than 20%.

IPC Classes  ?

• B21B 1/46 - Metal rolling methods or mills for making semi-finished products of solid or profiled cross-sectionSequence of operations in milling trainsLayout of rolling-mill plant, e.g. grouping of standsSuccession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting

Abstract

Mill rolls capable of rolling long kilometres used for ESP production line and a method for rolling long kilometres using the mill rolls. The mill rolls comprise rolls (3, 4), a bearing box (2) and a roll shifting hydraulic cylinder (1), wherein the middle portion of the surface of said roll sinks inwards, one end of the rolls is frustum-shaped, smaller and smaller outwards, so that the roll surface forms a compensation ramp, and the other end of the rolls is cylindrical. The upper roll (3) and the lower roll (4) have the same roll profile and are positioned in the opposite direction. The mill rolls are characterized by reduced runaway of the rolled product and a longer service life.

IPC Classes  ?

• B21B 27/02 - Shape or construction of rolls

Abstract

A thin slab nozzle contains a central bore extending downstream along longitudinal axis X1 from an inlet orifice at an upstream end. The central bore comprises an upstream bore portion with a height Ha, in communication with a converging bore portion of height He, in communication with a thin bore portion of height Hf ending at the upstream end of a divider, and first and second front ports separated from one another by the divider and coupled to the central bore portion at least partially at the converging bore portion. X2 is a transverse axis, normal to X1, along which the nozzle becomes thinner in a downstream portion. In a section of the thin slab nozzle along a symmetry plane Π1 defined by X1 and by X2, the bore wall of the converging bore portion is curved at all points, and Hf/He≤1.

IPC Classes  ?

• B22D 11/04 - Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds
• B22D 11/041 - Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds for vertical casting
• B22D 41/50 - Pouring-nozzles
• B22D 11/10 - Supplying or treating molten metal

Abstract

The present invention concerns a thin slab nozzle for casting thin slabs made of metal at a very high mass-flow, said thin slab nozzle comprising: a central bore (50) defined by a bore wall and opening at inlet orifice (50μ) and extending therefrom along the longitudinal axis XI until it is closed at an upstream end (10μ) of a divider (10), said central bore comprising: an upstream bore portion (50a) comprising the inlet orifice and extending over a height, Ha, and, adjacent thereto, forming an upstream boundary (5a) with a converging bore portion (50e) of height He located in the connecting portion of the thin slab nozzle, and adjacent thereto a thin bore portion (50f) of height Hf located in the diffusing portion of the thin slab nozzle and ending at the level of the upstream end (10μ) of the divider (10), first and second front ports (51) separated from one another by said divider (10) and coupled to the central bore portion (50a) at least partially at the converging bore portion (50e); characterized in that, in a section of the thin slab nozzle along the first symmetry plane Π1 defined by (X1, X2) wherein X2 is normal to X1, the geometry of the wall of the central bore (50) is characterized as follows: - the radius of curvature at any point of the bore wall of the converging bore portion (50e) is finite, and the ratio of the height, Hf, of the thin bore portion (50f) to the height, He, of the converging bore portion (50e) is not more than 1, Hf/He ≤1.

IPC Classes  ?

• B22D 11/10 - Supplying or treating molten metal
• B22D 41/50 - Pouring-nozzles

Abstract

A device for supporting and oscillating continuous casting molds in continuous casting plants includes at least one support suitable to support a continuous casting mold, the support including a fixed assembly restrained to a frame of the device and a movable assembly that is slidably restrained to the fixed assembly in a vertical direction and connected to a servomechanism suitable to move it in a reciprocating manner relative to the fixed assembly along the axial direction, the movable assembly including a plurality of channels suitable to allow a flow of a cooling fluid to and from a cooling circuit of the mold, the channels being supplied by supply pipes arranged along the vertical direction. The device further includes at least one connecting pipe suitable to allow to connect a supply pipe, the connecting pipe having a T shape and including a first duct rigidly connected to the movable assembly in a horizontal direction, as well as a second and a third duct extending from the first duct in opposite ways along the vertical direction, the second and third ducts being respectively connected to first and second end portions of the fixed assembly through further axially deformable ducts and being respectively a blind duct and a flow-through duct suitable to allow the cooling fluid to flow towards the first and the second ducts. The second and third ducts, and preferably also the first duct, of the at least one connecting pipe have the same diameter of the supply pipes.

IPC Classes  ?

• B22D 11/053 - Means for oscillating the moulds
• B22D 11/055 - Cooling the moulds

Abstract

A device (10) for supporting and oscillating continuous casting moulds in continuous casting plants comprises at least one support (30) suitable to support a continuous casting mould (40), said support (30) comprising a fixed assembly (31) restrained to a frame (20) of the device (10) and a movable assembly (32) that is slidably restrained to said fixed assembly (31) in a vertical direction (A) and connected to a servomechanism (38) suitable to move it in a reciprocating manner relative to the fixed assembly (31) along said axial direction (A), said movable assembly (32) comprising a plurality of channels (50, 60) suitable to allow a flow of a cooling fluid to and from a cooling circuit of said mould (40), said channels (50, 60) being supplied by supply pipes arranged along the vertical direction (A). The device(10) further comprises at least one connecting pipe (70) suitable to allow to connect a supply pipe, said connecting pipe (70) having a T shape and comprising a first duct (71) rigidly connected to the movable assembly (32) in a horizontal direction (B), as well as a second and a third duct (72, 73) extending from said first duct (71) in opposite ways along the vertical direction (A), said second and third ducts (72, 73) being respectively connected to first and second end portions (80, 81) of the fixed assembly (31) through further axially deformable ducts (100, 101) and being respectively a blind duct (72) and a flow-through duct (73) suitable to allow the cooling fluid to flow towards the first and the second ducts (71, 72). The second and third ducts (72, 73), and preferably also the first duct (71), of the at least one connecting pipe (70) have the same diameter of the supply pipes.

IPC Classes  ?

• B22D 11/053 - Means for oscillating the moulds
• B22D 11/055 - Cooling the moulds