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
  • B22D11/14—Plants for continuous casting
  • B22D11/145—Plants for continuous casting for upward 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
  • B22D11/12—Accessories for subsequent treating or working cast stock in situ
  • B22D11/124—Accessories for subsequent treating or working cast stock in situ for cooling
  • B22D11/1248—Means for removing cooling agent from the surface of the cast stock

Definitions

• the present invention relates to the method as described in the preamble of patent claim 1.
• the invention also relates to the equipment described in the preamble of patent claim 6.
• Conventional vertically upward continuous casting where continuous casting in an upward direction takes place from the free surface of the melt, is known from e.g. Finnish patent 46693 and corresponding US patent 3,746,077.
• Conventional continuous casting equipment comprises a primary cooler connected to the casting nozzle as well as a secondary or re-cooler.
• the total length of the cooler may be of the order of 2 m.
• the crystallization and primary cooling of the metal take place in the primary cooler, particularly in the nozzle part, the length of which is about 1 - 5% of the total length of the cooler.
• Secondary cooling takes place in the top part of the primary cooler and in a separate secondary cooler.
• the upper part of the primary cooler and the secondary cooler consist of an outer shell, a separate cooling water distribution pipe and an inner pipe.
• the cooling agent such as flowing water, is outside the inner pipe and the wire, rod or tube to be cast is inside the inner pipe.
• the relatively low investment costs of the production line have been a significant factor in the conventional vertical casting process, when used for relatively limited production levels due to the nature of the product to be cast.
• the relative investment costs of the production line could be further reduced by increasing the casting rate, in which case the number of coilers and coolers required would decrease.
• the inefficiency of the secondary cooling has been an obstacle to the increase of the casting rate.
• the maximum casting rate e.g. for an deoxidized cast wire with an 8mm diameter is about 5 - 6 m/min when the cooler is clean, the cooling water sufficiently cold and the melt quality acceptable.
• the aim of this invention is to achieve a cooling solution, which enables the increase of the casting rate in conventional upward continuous casting.
• Another aim of the invention is to achieve a cooling solution that enables an increase in cooling efficiency and production capacity of conventional UPCAST® equipment already in use.
• the invention is based on the concept whereby the upper part of the casting machine is arranged so that a jet of cooling agent is aimed directly onto the product to be cast in such a way that the cooling agent cannot travel back into the cooler and/or into the melt.
• An essential feature of the method of the present invention is that, in addition to primary cooling, the product to be cast is cooled outside the walls of the furnace at least in one another cooling stage by a jet of cooling agent sprayed on the surface of the piece to be cast in such a way that the cooling agent is prevented from contact with the melt in the furnace.
• the direct jet of cooling agent lowers the temperature of the product sufficiently to prevent harmful oxidation taking place.
• This direct secondary cooling according to the invention can increase the casting rate, thus providing more effective casting equipment with a reduced amount of cooling and coiling machines compared with conventional facilities.
• the cooling efficiency and production capacity of conventional UPCAST® equipment can also be increased by adding cooling equipment according to this invention.
• One embodiment of the method according to this invention is characterized by the recovery and reutilization of the cooling agent. Then the cooling cycle is closed and additives can be used in the cooling water.
• the cooling agent is recovered with collection devices, such as collecting pools, arranged to the connection of the cooling agent jets.
• collection devices such as collecting pools
• An extremely effective recirculation of cooling agent can be achieved with collecting pools. This also prevents liquid from getting into the furnace.
• the cooling agent jet is directed onto the cast product at the point of its guiding devices, such as bending rolls.
• the cooling agent jet is directed onto the cast product at the point of its guiding devices, such as bending rolls.
• highly effective cooling impact will be achieved.
• Another advantageous embodiment of the invention has the characteristic of surrounding the product to be cast with a shielding gas for at least part of the distance between the primary cooler and the cooling agent jet. This enables an increase in casting rate, while preventing the product to be cast from oxidizing between the cooler and the cooling agent jet.
• Figure 1 shows a vertical casting apparatus, where an arrangement according to the invention is applied
• FIG. 2 illustrates a detail of the apparatus according to the invention
• Figure 3 shows another embodiment of the invention
• FIG. 4 is a diagram of the equipment according to the invention.
• Figure 1 shows a conventional vertical upcasting apparatus, comprising a smelting and casting furnace 1 , an essentially vertical primary cooler 2 partially set into the furnace, with the casting nozzle at least partially inserted in the melt of the furnace.
• the melt is solidified inside the casting nozzle and primary cooler so that the cast product formed, 3 and 3', such as wire, rod or tube, can be pulled by the drawing rolls of a drawing unit 4 over a guiding device 5, for instance a bending roll.
• the cast product and its route are shown in the drawing by the broken lines.
• the arrows indicate the direction of the cast product.
• the apparatus in the drawing includes at least one cooling agent jet 6, which is arranged on the outside of the furnace walls in such a way that the cooling agent to be sprayed from the jet cannot travel into the furnace.
• the product to be cast in addition to primary cooling, is cooled outside the furnace 1 walls at least in one another cooling stage by a jet 6 of cooling agent aimed at the surface of the product to be cast 3 and 3', in such a way that the passage of cooling agent into the melt within the furnace is prevented.
• Figure 2 shows a detail of the cooling equipment according to the drawing, where the cooling agent jets 6 are arranged to cool two separate cast products, 3 and 3'. Typically, in the direction shown in Figure 2 there will be several cast products 3 and 3' one after another (side by side). For reasons of clarity, the attachments for the cooling agent jets 6 have been omitted from the drawing.
• the jets are normally fixed to the cross-bracket of the support structures 14 of the bending rolls 5.
• the cooling agent in the arrangement according to the invention is recovered and re-used.
• the cooling agent is collected with a collection device 7, such as collecting pools arranged at the connection of the cooling agent jets 6.
• the cooling agent spray jets 6 are usually arranged so that there is at least one jet per cast product 3, 3'. According to one advantageous embodiment of the invention, the cooling agent spray is directed onto the cast product 3, 3', at the point of the guiding device 5, e.g. bending roll.
• Figure 3 shows that the product to be cast may be surrounded by shielding gas for at least part of the distance between primary cooling and the cooling agent spray.
• a shielding gas space 8 such as a casing tube, is arranged in the apparatus.
• each cast product 3, 3' is provided with its own shielding gas space, to which the shielding gas is routed from a feed unit 9.
• the shielding gas for instance nitrogen, prevents oxidation of the cast product before the cooling agent jet.
• FIG. 4 shows a diagram of a cooling arrangement comprising a cooling agent tank 10, from where the cooling agent is recirculated with a pump unit 11 to the spray jets 6, which are preferably equipped with a valve unit 12. Part of the cooling agent flows from the spray jets 6 to the collection device 7, for example collecting pools, from where the cooling agent is returned to the cooling agent tank 10.
• the tank is usually provided with a heat exchanger 13 in order to regulate the temperature of the cooling agent inside the tank.
• the use of additives in the cooling agent which is typically water, is possible because the circulation of the cooling agent is closed.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Continuous Casting (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=8559011

Family Applications (1)

Country Status (10)

Cited By (3)

Families Citing this family (4)

Family Cites Families (15)

• 2000
  • 2000-09-05 FI FI20001945A patent/FI20001945A/fi not_active Application Discontinuation
• 2001
  • 2001-09-03 MY MYPI20014134 patent/MY133876A/en unknown
  • 2001-09-05 AU AU2001285969A patent/AU2001285969A1/en not_active Abandoned
  • 2001-09-05 JP JP2002524660A patent/JP2004508198A/ja not_active Withdrawn
  • 2001-09-05 US US10/363,105 patent/US20030178172A1/en not_active Abandoned
  • 2001-09-05 CN CNB018151906A patent/CN1209211C/zh not_active Expired - Fee Related
  • 2001-09-05 WO PCT/FI2001/000765 patent/WO2002020194A1/en not_active Application Discontinuation
  • 2001-09-05 KR KR10-2003-7003207A patent/KR20030036751A/ko not_active Application Discontinuation
  • 2001-09-05 EP EP01965302A patent/EP1315588A1/en not_active Withdrawn
  • 2001-09-05 EA EA200300340A patent/EA004125B1/ru not_active IP Right Cessation

Non-Patent Citations (1)

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