Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
  • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
  • B22D11/12—Accessories for subsequent treating or working cast stock in situ
  • B22D11/124—Accessories for subsequent treating or working cast stock in situ for cooling
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
  • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
  • B22D11/04—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
  • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
  • B22D11/04—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds
  • B22D11/041—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds for vertical casting
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
  • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
  • B22D11/04—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds
  • B22D11/055—Cooling the moulds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
  • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
  • B22D11/04—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds
  • B22D11/059—Mould materials or platings
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
  • C25D5/34—Pretreatment of metallic surfaces to be electroplated
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
  • C25D5/48—After-treatment of electroplated surfaces
• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
  • C25D5/54—Electroplating of non-metallic surfaces
  • C25D5/56—Electroplating of non-metallic surfaces of plastics

Definitions

• the present invention concerns a crystallizer for continuous casting, usable in the iron and steel making industry to cast billets, blooms or other similar products, of any type and cross section.
• the invention also concerns the method for its production.
• Different crystallizers for continuous casting are known, suitable to cast billets, blooms or other iron and steel products, each having a tubular body provided with a through longitudinal cavity with a desired cross section, corresponding to the cross section of the product to be cast, for example circular, elliptical or polygonal, and in which the liquid casting metal is suitable to pass.
• a plurality of channels are normally made longitudinally, which are part of a closed cooling circuit in which a cooling liquid, for example water, is made to circulate.
• a crystallizer for continuous casting comprises a first tubular body, or internal tubular body, which defines a casting channel for the liquid metal, and a second tubular body, or external tubular body, which is associated externally to the first tubular body.
• the internal tubular body is provided, on its external contact surface with the external tubular body, with support ribs and connection ribs alternating with the support ribs.
• the support ribs and the connection ribs protrude toward the outside and extend along the axial extension of the crystallizer.
• the function of the support ribs is to maintain the external tubular body distanced from the internal one, while the connection ribs are inserted in attachment seatings made on the internal surface of the external tubular body, defining a fixed-joint mechanical coupling, making the internal tubular body able to be disassembled from the external tubular body.
• connection ribs and the support ribs define, between the internal tubular body and the external tubular body, a plurality of hollow spaces in which a cooling fluid flows.
• the fixed-joint mechanical coupling between the internal tubular body and the external tubular body does not guarantee a hydraulic seal of the cooling fluid in the hollow spaces, since the support ribs have only a distancing function for the external tubular body and are not able to guarantee the hydraulic seal between adjacent hollow spaces.
• document EP-A- 1.468.760 provides that the internal tubular body is made of metal material, for example copper, while the external tubular body is made of a metal or non-metal material, a composite for example, such as laminate carbon.
• One purpose of the present invention is to make a crystallizer for continuous casting, with cooling channels incorporated in the walls, which overall has an increased structural rigidity without increasing the thickness of its walls, in order to guarantee an increased casting efficiency and an increased quality of the product exiting from the crystallizer.
• Another purpose of the present invention is to make a crystallizer for continuous casting, of the type indicated above, that is simple in construction and at the same time has a reduced cost compared to known crystallizers, even when the crystallizer has large sizes, for example a diameter or width equal to or more than 800 mm, reducing to a minimum the use of metal, for example copper, needed to make the walls of its tubular body.
• Another purpose of the present invention is to make a crystallizer for continuous casting, of the type indicated above, that is reliable and can be used, without any contraindication and with maximum efficiency, even with a radioactive rod used to detect the level of liquid metal inside the crystallizer during casting.
• Another purpose of the present invention is to perfect a method to make a crystallizer for continuous casting, of the type indicated above, that allows to reduce production costs without reducing the characteristics of structural rigidity, safety, reliability and thermal and thermo-mechanical efficiency of the crystallizer itself.
• Another purpose of the present invention is to perfect a method that allows to make a crystallizer for continuous casting, of the type indicated above, easily and with simple work steps, that can have any shape and cross section, for example circular, elliptical or polygonal.
• the Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.
• a crystallizer for continuous casting comprises a tubular body with at least a wall that defines a through longitudinal casting cavity and a plurality of longitudinal grooves made at least on a part of an external surface of the at least one wall and open toward the outside thereof.
• a covering binding comprising one or more overlapping layers of fiber material, is irremovably wound around the external surface of the at least one wall, so as to create an indivisible whole between the at least one wall with the longitudinal grooves and the covering binding.
• covering binding we mean a material comprising a plurality of fibers adjacent to each other to define one or more bands that, once in position, cover at least part of the external surface of the wall.
• the layers of fiber can be impregnated with a polymer material, which, once the covering binding has been wound around the external surface of the wall, is polymerized and determines the solid and irremovable attachment of the covering binding to the wall.
• the covering binding wound tightly around the crystallizer in a direction mainly transverse to its longitudinal direction, limits the deformations and movements of the walls, maintaining the internal conicity, while allowing the longitudinal dilation due to heat phenomena for example between 0 and 4 mm.
• the covering binding is in direct contact with the external surface of the at least one wall and closes the longitudinal grooves.
• Corresponding cooling channels are thus obtained, configured to make a cooling liquid flow inside them, for example water, suitable to cool the tubular body of the crystallizer.
• the covering binding is in direct contact with a metal layer made with electrolytic deposition techniques; the metal layer, in its turn, is in contact with the external surface of the at least one wall and closes the longitudinal grooves to form a corresponding plurality of cooling channels.
• the present invention describes the use of electrolytic deposition with the purpose of creating sealed cooling channels on the external surface of the walls of the crystallizer.
• the covering binding makes rigid the whole made by the at least one wall of the crystallizer and the metal layer associated thereto.
• the longitudinal grooves are closed by at least a plate associated to the external surface of the at least one wall so as to define a corresponding plurality of cooling channels inside which a cooling liquid flows.
• the covering binding is in direct contact with the at least one plate so as to reinforce and increase the security of the connection between the at least one plate and the at least one wall.
• the longitudinal grooves are closed by at least a lamina made of a fiber-reinforced polymer material, fiberglass for example, associated to the external surface of the at least one wall to define a corresponding plurality of cooling channels inside which a cooling liquid flows.
• the covering binding in this case, is located in direct contact with the lamina of fiber-reinforced polymer material in order to make rigid the whole made by the at least one wall and the lamina of fiber- reinforced polymer material.
• the covering binding can be wound around the wall defining even variable thicknesses in a longitudinal direction in the most stressed zones, for example the meniscus zone.
• the variation in thickness in a longitudinal direction of the covering binding can even be some millimeters.
• the covering binding, in the non-thickened zone has a thickness comprised between lmm and 8mm.
• variable thickness of the fibers which surround the crystallizer, after complete polymerization of the covering binding allows to work with machine tools on the external containing surface so as to obtain seatings for housing packings or break-pins.
• the method to make a crystallizer for continuous casting comprises a step in which a tubular body is made, of metal for example, more specifically of copper, with at least a wall that defines a through longitudinal casting cavity and a plurality of longitudinal grooves made at least on one part of the external surface of the at least one wall and open toward the outside thereof.
• the method according to the present invention also comprises a step in which a covering binding, comprising one or more layers of fiber material, is associated to the external surface of the at least one wall.
• the covering binding comprises a band made using at least a fiber, impregnated or pre- impregnated with for example a volumetric ratio of fibers of 60%, such as carbon, and glue or polymer resin of 40%.
• the polymer material is the type resistant to high temperatures, that is, equal to or more than 100°C, such as a polymer for example chosen from the group comprising poly amide, epoxy or polyester resins.
• the fibers can be chosen from a group comprising carbon fibers, glass fibers, aramid fibers or similar.
• the covering binding in fiber which becomes rigid when the polymer solidifies by polymerizing, can be applied using any known technique, including the filament winding technique.
• the polymerization of the polymer can occur through heat polymerization steps, that is, reticulation of the resin, called curing.
• the crystallizer is heated to a temperature comprised between 30°C and 120°C and kept at this temperature for a period comprised between 20 and 200 minutes. These conditions determine the reticulation of the polymer resin and therefore a solidarization of the binding to the wall or walls.
• a post-curing step can be provided during which the crystallizer is heated to a temperature comprised between 80°C and 200°C and kept at this temperature for a period comprised between 1 hour and 20 hours.
• the crystallizer is kept in rotation around its own axis.
• the crystallizer after the curing and possibly post-curing steps, can be subjected to a forced cooling.
• the operation of winding the covering binding on the wall can include the installation, on a suitable apparatus and by means of a dedicated apparatus, of the wall in rotating mode around an axis of rotation and subsequent winding of the covering binding perpendicularly to the axis of longitudinal development, or with a winding angle comprised between 0° and 10°, preferably between 0° and 5°, with respect to the perpendicular to the axis of longitudinal development of the crystallizer.
• the winding operation can occur with a controlled tension of the fibers, for example from IN and 50N per fiber.
• crystallizers of any shape, or with any cross section, for example polygonal, circular, or elliptical, and even of considerable sizes, for example with diameters, or widths, equal to or more than 800mm;
• the method according to the present invention before winding the one or more layers of fiber material it provides to fill the longitudinal grooves with disposable material, for example wax, to deposit a metal layer on the external surface of the at least one wall by electrolytic deposition techniques, in order to close the longitudinal grooves, and to subsequently remove the disposable material from the longitudinal grooves so as to define corresponding cooling channels.
• disposable material for example wax
• - fig. 1 is a perspective and schematized view of a crystallizer for continuous casting according to a first form of embodiment of the present invention
• - fig. 2 is an enlarged detail of the crystallizer in fig. 1 ;
• - fig. 3 is a perspective and schematized view of a detail of a crystallizer according to a second form of embodiment of the present invention.
• - fig. 4 is a schematized view of a detail of a crystallizer according to a third form of embodiment of the present invention.
• - figs. 5 and 6 are schematized views of possible variants of the crystallizer according to the present invention.
• a crystallizer 10 for continuous casting in a first form of embodiment, comprises a tubular body 1 1 with a wall 12, for example made of copper or its alloys, which defines a through longitudinal casting cavity 13.
• the thickness of the wall 12 is for example comprised between 10 mm and 50 mm.
• Each longitudinal groove 14 is open toward the outside of the wall 12.
• a covering binding 15 which in this case comprises one or more layers of a band 16 of fiber, impregnated or pre-impregnated with a polymer resistant to high temperatures (that is, equal to or higher than 100°C), is in direct contact with the external surface of the wall 12 and closes the longitudinal grooves 14 from the outside. In this way corresponding channels 17 are made, configured to make a cooling liquid, for example water, flow inside them.
• the band 16 defines a plurality of layers wound on the external surface of the wall 12 of the crystallizer 10.
• a crystallizer 110 (fig. 3) according to the present invention comprises, interposed between the covering binding 15 and the wall 12, a metal layer 18 made with electrolytic deposition techniques, for example as described in the application for a patent of industrial invention UD2013A000013 cited above.
• the metal layer 18 that hermetically closes the longitudinal grooves 14 from the outside of the wall 12 and defines the plurality of cooling channels 17.
• the covering binding 15 is in direct contact with the metal layer 18, in order to make rigid the whole made up of the latter and the wall 12. This allows to have a very contained thickness of the metal layer 18, for example in the range of one or two millimeters.
• the covering binding 15 in this case has a containing function of the metal layer 18 and guarantees the seal of the latter even at high working pressures of the cooling fluid circulating in the channels 17.
• the metal layer 18 can be replaced by a lamina 23 made of a fiber-reinforced polymer material which, closing the longitudinal grooves 14 from the outside, defines the corresponding plurality of cooling channels 17.
• the covering binding 15 is wound intimately in direct contact with the lamina 23 to make rigid the whole constituted by the wall 12 and the lamina 23.
• a crystallizer 210 (fig. 4) according to the present invention comprises a tubular body 21 1 provided with a plurality of walls 212 defining a longitudinal casting cavity 213.
• At least one plate 219 in this specific case four plates 219, are associated to the external surface of the tubular body 21 1, for example welded or glued, and are provided to close the longitudinal grooves 14 made on the walls 212 of the tubular body 21 1 from the outside and to define the cooling channels 17.
• the plates 219 can be associated to the external surface of the tubular body 211, for example, by braze welding or structural gluing, in the same way as described in the Italian application for a patent of industrial invention UD2012A000193 in the name of the Applicant.
• the covering binding 15 is in direct contact with the surface of the plates 219 that is external during use, to reinforce them and increase the secure seal of the braze welding.
• Forms of embodiment of the present invention provide that the covering binding 15 has a constant thickness along the longitudinal extension of the tubular body 1 1, 21 1.
• FIG. 5 Other forms of embodiment, one of which is shown in fig. 5, provide that the covering binding 15 is provided with a thicker portion 20 that has a greater thickness than the thickness along the longitudinal extension of the tubular body 1 1 or 21 1. In this way it is possible to generate zones of the crystallizer 10 with variable resistance and rigidity along its longitudinal extension that are determined, for example, depending on a variable development of the pressure of the cooling fluid in the cooling channels 17 or on different conditions of mechanical and/or heat stress to which it can be subjected during normal use. According to other forms of embodiment of the present invention, shown for example in fig. 6, mechanical workings, for example to define circumferential seatings 21 for housing sealing rings or holes 22 for the insertion of break-pins, can be made on the covering binding 15.
• the method for producing each of the crystallizers 10, 110, 210 for continuous casting described heretofore comprises a step in which the tubular body 11, 21 1 is made, with the wall 12 or walls 212 that define the longitudinal cavity 13, 213 and the plurality of longitudinal grooves 14, made for example by removing material, such as milling, at least on one part of the wall 12 or walls 212, and open toward the outside thereof.
• the method also comprises a step in which a covering binding 15, as described heretofore, is associated to the external surface of the wall 12 or walls 212.
• the binding 15 comprises the band 16 made with one or more overlapping layers, using at least a fiber impregnated or pre-impregnated with a polymer resistant to high temperatures, as indicated above, that is chosen for example from a group comprising poly amide, epoxy or polyester resins.
• the wall 12 or walls 212 is or are installed on a winding machine, for example by means of clamps or specific equipment to allow the subsequent winding operation of the fibers around it.
• the fibers can be polymerized in different curing passes, for example a curing at 30-120°C for 20-200 minutes, followed by a post-curing at 80-200°C for 1-20 hours depending on the resin applied.
• the covering binding 15 can be applied using the filament winding technique.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Metallurgy (AREA)
• Electrochemistry (AREA)
• Materials Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Organic Chemistry (AREA)
• Moulding By Coating Moulds (AREA)
• Continuous Casting (AREA)
• Rigid Pipes And Flexible Pipes (AREA)
• Molds, Cores, And Manufacturing Methods Thereof (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Priority Applications (8)

Applications Claiming Priority (2)

Related Child Applications (2)

Publications (2)

Family

ID=49035891

Family Applications (1)

Country Status (9)

Cited By (4)

Families Citing this family (4)

Citations (4)

Family Cites Families (25)

• 2013
  • 2013-06-28 IT IT000090A patent/ITUD20130090A1/it unknown
• 2014
  • 2014-06-30 CN CN201480048081.0A patent/CN105473253B/zh active Active
  • 2014-06-30 JP JP2016522943A patent/JP6110567B2/ja active Active
  • 2014-06-30 WO PCT/IB2014/062721 patent/WO2014207729A2/en active Application Filing
  • 2014-06-30 EP EP14755142.8A patent/EP3013498B1/en active Active
  • 2014-06-30 US US14/901,642 patent/US20160144424A1/en not_active Abandoned
  • 2014-06-30 ES ES14755142T patent/ES2834634T3/es active Active
  • 2014-06-30 CA CA2916854A patent/CA2916854C/en active Active
  • 2014-06-30 PL PL14755142T patent/PL3013498T3/pl unknown

Patent Citations (4)

Also Published As

Similar Documents

Legal Events