Danieli & C. Officine Meccaniche S.p.a.

International Rolling Mill Consultants, Inc.

Danieli United

Bruno Di Giusto

Giovanni Coassin

Giampietro Benedetti

Andrea Carboni

Fulvio Fasano

Wogler D Ruzza

Mirco Striuli

Alfredo Lavazza

Alessandro Dorigo

Vladimir B Ginzburg

Fausto Drigani

Paolo Bobig

Pietro Morasca

Rolling method for thin flat products, used in the production of flat rolled products with a final thickness in the range of 0.6-1.5 mm or more, up to 2.0-3.0 mm, in a plant suitable to work thicknesses of up to 25.4 mm, the method being applied to slabs with a thickness of between 50 and 90 mm if arriving directly from the continuous casting machine or on slabs with a greater thickness, of between 80 and 200-250 mm, if fed from a furnace to accumulate and heat the slabs (22), the method comprising at least a first heat treatment, a roughing or pre-finishing pass, a temperature equalisation treatment and a finishing pass in a finishing train (19) comprising at least three reduction passes, the finishing pass being followed by a step of cooling and coiling the flat finished product, the product at the outlet of the roughing or pre-finishing pass being in the austenitic state .gamma., the finishing pass taking place in the rolling line (10) at least partly in the ferritic step or in the austenitic step, as desired. Rolling line adopting the method as above, wherein the finishing train (19) cooperates with a system (24) to condition and adjust the temperature of the slab.

Rolling method for thin flat products and relative rolling line

Method for the controlled pre-rolling of thin slabs (20) leaving a continuous casting plant, whereby the pre-rolling is carried out with a plurality of pairs of rolls (14-16), a first pre-rolling assembly (10) being positioned immediately downstream of foot rolls (12) of a mold (11), at least one displaceable roll (16) being included in the pairs of rolls (14-16), the pairs of rolls (14-16) being associated with pressure transducer (18) and hydraulic capsule (17), position transducer (24) being included. The pressure transducer (18) and position transducer (24) can be associated with a data processing unit (21), at least the first of the pairs of rolls (14-16) processing a slab (20) which has just emerged from the mold (11) with a thin solidified skin. The method achieves a pre-rolling with a reduction of the thickness of the slab (20) leaving the last pair of pre-rolling rolls (14-16) by at least 10% so as to eliminate the liquid core and to bring into contact the zones in a two-phase condition in order that the central solidification structure be refined and the central separation be minimized. Device suitable to carry out the controlled pre-rolling of thin slabs according to the above method, which comprises an element (25a) to monitor the temperature of the liquid bath in a tundish, an element (25b) to monitor the temperature of a slab (20), an element (26) to monitor the speed of the slab (20) and an element (28) to monitor the inclusion of a liquid cone.

Method for the controlled pre-rolling of thin slabs leaving a continuous

Machine to sharpen bars to a point, especially bars to be drawn, which comprises at least one sharpening assembly and at least one assembly for displacement of the bar in relation to the sharpening assembly, the sharpening assembly (31) consisting of two counterpart rolls (11) each of which contains on the plane of positioning of the bar a groove (24) including at least two sections of reduction, means (14-15) being comprised for the circumferential positioning of the rolls (11) at the desired section of reduction, there also being included at least one rolling assembly (27a) upstream of the sharpening assembly (31) and at least one rolling assembly (27b) downstream of the sharpening assembly (31), such rolling assemblies (27) operating on the bar on a plane substantially at a right angle to the plane of reduction.

Machine to sharpen bars to a point

Line to produce strip and/or sheet or a combined line for strip/sheet, starting from at least one plant for the continuous casting of thin or medium slabs, the continuous casting plant comprising in sequence a continuous casting machine (12), at least one assembly (13) for shearing to size, a temperature restoration system, a rolling train (17-117) and a possible assembly (19) for the cooling of strip/sheet. A device to accelerate the speed of feed of the slabs is included downstream of the assembly (13) for shearing to size. The temperature-restoration system includes an induction furnace (14) with at least one working frequency to heat the surface and edges of the slabs, the induction furnace (14) being followed by a low-speed descaler (115) and by a tunnel furnace (16). An emergency shears (24) and high-speed descaler (15) is included between the tunnel furnace (16) and the rolling train (17-117).

Line to produce strip and/or sheet

Method for the controlled pre-rolling of thin slabs (20) leaving a continuous casting plant, whereby the pre-rolling is carried out with a plurality of pairs of rolls (14-16) grouped together in one or more pre-rolling assemblies (10), the first of the pre-rolling assemblies (10) being positioned immediately downstream of foot rolls (12) of a mold (11), at least one displaceable roll (16) being included in the pairs of rolls (14-16), the pairs of rolls (14-16) being associated with pressure transducer means (18) and hydraulic capsule means (17), position transducer means (24) being included. The pressure transducer means (18) and position transducer means (24) can be associated with a data processing unit (21), at least the first of the pairs of rolls (14-16) processing a slab (20) which has just emerged from the mold (11) with a thin solidified skin. The method achieves a pre-rolling with a reduction of the thickness of the slab (20) leaving the last pair of pre-rolling rolls (14-16) by at least 10% so as to eliminate the liquid core and to bring into contact the zones in a two-phase condition in order that the central solidification structure be refined and the central separation be minimized. Device suitable to carry out the controlled pre-rolling of thin slabs according to the above method, which comprises means (25a) to monitor the temperature of the liquid bath in a tundish, means (25b) to monitor the temperature of a slab (20), means (26) to monitor the speed of the slab (20) and means (28) to monitor the inclusion of a liquid cone.

The present invention relates to a compact rolling plant and method for using it to manufacture hot rolled metal strip. The rolling mill and method are capable of rolling both thick and thin slabs with minimum delays between slabs. The complete rolling of a bar or a strip below a critical transformation temperature range may be done at any speed without heat losses in unrolled portions of the strip or bar.

Apparatus and method for the manufacture of hot rolled metal strip

Assembly to wind-unwind thin slabs which cooperates with a continuous casting plant (11) producing thin slabs (12) and is positioned on the same axis as that plant (11), a heating and temperature-equalization furnace (17) being included upstream of the winding-unwinding assembly (10), at least one pair of drawing rolls (23) cooperating with the winding-unwinding assembly (10), which comprises two coiling-uncoiling units (20a-20b) positioned circumferentially equidistant from, and on, a base plate (21) able to rotate about a substantially central vertical axis, one of the units (20a-20b) taking over alternately the position and function of the other unit (20a-20b) and viceversa, each coiling-uncoiling unit (20a-20b) being equipped with its own lead-in guide (26) and powered rolls (28), the powered rolls (28) being coplanar and positioned below the thin slab (12) and cooperating with a curvature-imparting roll (29), which can be moved from a position of cooperation with, and between the powered rolls (28) to an upper position when a coiled roll (33) has been fully coiled, the curvature-imparting roll (29) cooperating with an actuator (32) that adjust its pressure towards the powered rolls (28), the actuator (32) being associated with an arm (30) that supports the curvature-imparting roll (29), the lead-in guide (26) lying on the same plane as the plane of feed of the thin slab (12) and as the upper side of the powered rolls (28).

Assembly to wind-unwind thin slabs

Furnace with refractory longitudinal members and with central charging for heating and storing hot products, whereby the central charge arrives from a continuous casting plant or from previous hot processes, the furnace (10) comprising a first furnace portion (10a) for the introduction of a cold charge (12) and for storage and also a second furnace portion (10b) for discharge of the heated charge (15), the first (10a) and second (10b) furnace portions comprising stationary longitudinal members (23) and movable longitudinal members (24), the central charging taking place between the first (10a) and second (10b) furnace portions, a central intake and guide channel (22) being defined as a furnace bed by the plurality of stationary longitudinal members (23) cooperating with the respective plurality of movable longitudinal members (24a-24b) of the first (10a) and second (10b) furnace portions, the movable longitudinal members (24a-24b) in their raised position substantially facing each other, the width of the central intake and guide channel (22) and possibly the height of the movable longitudinal members (24) depending on the cross section of the hot product (26) being charged.

Furnace with refractory longitudianl members and with central charging

Each continuous casting line is associated with a first insulated tunnel (18) followed by a second temperature-equalization furnace tunnel (19) positioned in sequence between a continuous casting plant (11) and a rolling mill (13).

Tunnel system for a hot strip rolling mill linked to the continuous

Plant (10) to roll flat products which is fed in line by at least one continuous casting line (11) equipped with a shears (12) upstream of a temperature equalization furnace (13), the outlet of which is in the immediate vicinity of and in cooperation with the intake of a rolling train (10), the temperature equalization furnace (13) comprising within itself three walking beams (22-23-24), of which a first walking beam (22) cooperates with an intake roller conveyor (16) of the temperature equalization furnace (13) and is able to take continuously slabs (18) arriving from the at least one continuous casting line (11) and arranged on the intake roller conveyor (16) and to place them on a second intermediate walking beam (23), which is able to transfer these slabs (18) onto a third walking beam (24), which in turn can transfer the slabs (18) onto an outlet roller conveyor (15).

Plant to roll flat products

The plant (10) includes a temperature-equalization furnace (16) and an inlet shears (12) and an outlet shears (17) positioned respectively at the inlet and outlet of the furnace. The furnace is equipped with inlet and outlet doors, and cooled rollers connected to a motor for driving them in an oscillatory motion. In a method of continuous strip rolling using such a plant, in the event of an obstacle in a rolling train (18), the part of slab (20) not yet rolled is sheared by the outlet shears, returned to the furnace and kept there until the obstacle has been removed. During retention in the furnace, the slab is kept in a to-and-fro movement by means of oscillatory rotation of the cooled rollers.

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Udine, Italy

Bruno Di Giusto