摘要:
Method to control the profile of a strip (13) in a rolling stand for strip and/or sheet comprising at least two working rolls, respectively upper (11a) and lower (11b) and defining a reference pass-line (15) substantially coinciding with the center line of said strip (13), said rolls (11a, 11b) defining between them a transit gap (12) through which said strip (13) passes and is rolled and being supported at the ends by respective chocks, said method providing the axial movement (shifting) of said working rolls (11a, 11b) with respect to said pass-line (15), said working rolls (11a, 11b) having a shaped surface profile (14) which can be expressed by a polynomial equation, said method providing to apply a first value ("s1") of axial translation, or shifting, to said upper working roll (11a) and a second value ("s2") of axial translation, or shifting, to said lower working roll (11b), s1 being ≠ s2.
摘要:
Method to control the axial forces generated between the rolls in a rolling stand (10) for plane products (12) having at least a pair of working rolls (11a, 11b), a corresponding pair of back-up rolls (13a, 13b) and at least an intermediate roll (15a) located between one of the working rolls (11a) and a corresponding back-up roll (13b), axial translation means (16) associated with the working rolls (11a) to translate them axially (WR shifting), crossing means (19) associated with the intermediate roll (15a) to arrange it with its longitudinal axis (25a) inclined (IR crossing), that is, rotated on a horizontal plane by a set angle ( alpha ) with respect to the longitudinal axes (21a, 21b, 23a, 23b) of the working rolls (11a, 11b) and of the back-up rolls (13a, 13b); according to this method the WR shifting and the IR crossing are controlled by control means (30) so as to reduce to a minimum the axial forces generated in the working rolls (11a, 11b), and consequently the axial load on the corresponding thrust bearings (28).
摘要:
Rolling plant (10) comprising at least: a continuous casting device (11); a tunnel furnace (15) for maintenance/equalization and possible heating; a rolling train consisting of a roughing train comprising from 1 to 4 rolling stands (18a, 18b, 18c) and a finishing train comprising from 3 to 7 stands (21a-21e); a rapid heating unit (20), with elements able to be selectively activated, interposed between the roughing train and the finishing train. For each lay-out of the rolling line (10), the position of the rapid heating unit (20) which defines the number of stands (18a, 18b, 18c) which form the roughing train, disposed upstream of the unit (20), and the number of stands (21a-21e) which form the finishing train, disposed downstream of the unit (20), is calculated as a function of the product of the thickness and speed of the thin slab. The product is in turn a function of the hourly productivity in tons/hour desired to be obtained, and is made to work either in coil-to-coil mode, or in semi-endless mode or in endless mode. One of the three modes of the rolling process is selected according to the quality of the steel produced, to the maximum casting speed possible for the quality of steel, to the final thickness of the strip and to the production cost.
摘要:
Rolling plant and method to produce strip with a thickness varying from 0.7 mm to 20 mm, for all qualities of steel which can be cast in the form of thin slabs with a thickness comprised from 30 mm to 140 mm. The plant comprises at least a continuous casting device (11), a tunnel furnace (15) for heating and maintenance/equalization disposed downstream of the continuous casting device (11), a rolling train, disposed downstream of the tunnel furnace (15), consisting of a roughing train comprising from 1 to 4 rolling stands (18a, 18b, 18c) and a finishing train comprising from 3 to 7 stands (21a-21e), a rapid heating unit (20) with elements able to be selectively activated, interposed between said roughing train and said finishing train. The plant is made to work either in coil-to-coil mode, or in semi-endless mode or in endless mode.
摘要:
A rolling line (10) for the production of flat products (1 1 1) comprises a casting machine (12) suitable to continuously cast a thin slab (1 1), a temperature maintenance and homogenization unit (18), a rolling unit (22) comprising at least a double rolling stand (23a, 23b) of the Steckel reversing type downstream of the temperature maintenance and homogenization unit (18), at least a forming stand or roughing stand (20), directly connected immediately to the exit of the casting machine (12) and upstream of the temperature maintenance and homogenization unit (18), and suitable to reduce the thickness of the slab (1 1) just solidified. The forming stand or roughing stand (20) is configured to perform an adaptive reduction of the thickness of the cast slab (1 1) smaller than or equal to about 65% at least as a function of the thickness, width and type of material of the finished flat product. The rolling unit (22) is configured to perform a reduction of the reduction of the thin slab (1 1) coming from the temperature maintenance and homogenization unit (18) to a thickness comprised between about 1.2 mm and about 20 mm by means of at most three double rolling passes through the double rolling stand (23a, 23b).
摘要:
A continuous casting device (10) comprises at least a crystallizer (11) suitable for casting a metal product (12), and a plurality of guide and containing segments with rolls (14), the function of which is to accompany the cast product (12) exiting from the crystallizer (11). The device (10) comprises, in extension of or in an intermediate position to one or more of said guide and containing segments with rolls (14), one or more guide and containing segments (15) of the mixed type with panels and rolls, each comprising one or more guide rolls (16) disposed on at least one side of the product (12) and insulated and/or reflecting and/or heated panels (17) disposed on the opposite side of the product (12), so as to reduce the loss of temperature of the cast product (12) in transit.
摘要:
Method to control the planarity of flat products rolled with a rolling stand (10) having a pair of working rolls (11a, 11b), a corresponding pair of back-up rolls (13a, 13b) and at least an intermediate roll (15a) placed between one of said working rolls (11a) and a corresponding back-up roll (13b), axial translation means (16) and first bending means (17) associated with at least one of said working rolls (11a) to translate it axially (WR shifting) and respectively bend it (WR bending), crossing means (19) associated with said intermediate roll (15a) to arrange it with its longitudinal axis (25a) inclined (IR crossing), that is, rotated on a horizontal plane, with respect to the longitudinal axes (21a, 21b, 23a, 23b) of said working rolls (11a, 11b) and of said back-up rolls (13a, 13b), and second bending means (20) associated with said intermediate roll (15a) to bend it with respect to the horizontal plane (IR bending), said method providing a first static setting step, operating selectively at least on WR shifting and on IR crossing, and at least a second dynamic setting step, that is to say, during rolling, operating selectively at least on WR bending and IR bending.
摘要:
Rolling stand (10) for plane products and method to control the planarity of said plane products, said rolling stand comprising a pair of working rolls (11a, 11b), a corresponding pair of back-up rolls (13a, 13b) and at least an intermediate roll (15a) located between one of said working rolls (11a) and a corresponding back-up roll (13b), axial translation means (16) and bending means (17) being associated with at least one of said working rolls (11a) to translate it axially and respectively bend it, crossing means (19) being associated with said intermediate roll (15a) to arrange it with its longitudinal axis (25a) inclined, that is, rotated, with respect to the longitudinal axis (21a, 21b, 23a, 23b) of said working rolls (11a, 11b) and of said back-up rolls (13a, 13b).