Abstract: A system of twin-roll casting an ultra-thin slab or thick-strip of metal with a liquid core still present inside the hollow shell of the casting as it exits the nip of the opposing counter rotating casting rolls. The wide sides of the cast shell are formed against a recessed casting surface on each roll and the narrow end walls of the shell are formed against the tapered ends of the recessed area so one half of the narrow end wall is formed on each roll and the two halves are joined together at the nip to form the full perimeter of the metal casting. A liquid-cooled copper mold liner provides continued support to each of the four sides of the casting below the twin-rolls and contact with those chilled copper mold liners continues to remove heat from the liquid core of the casting enabling the shell to continue growing in thickness.

Abstract: A system of twin-roll casting an ultra-thin slab or thick-strip of metal with a liquid core still present inside the hollow shell of the casting as it exits the nip of the opposing counter rotating casting rolls. The wide sides of the cast shell are formed against a recessed casting surface on each roll and the narrow end walls of the shell are formed against the tapered ends of the recessed area so one half of the narrow end wall is formed on each roll and the two halves are joined together at the nip to form the full perimeter of the metal casting. A liquid-cooled copper mold liner provides continued support to each of the four sides of the casting below the twin-rolls and contact with those chilled copper mold liners continues to remove heat from the liquid core of the casting enabling the shell to continue growing in thickness.

Abstract: A process of making a multilayer metallic casting includes steps of simultaneously forming a first layer of a first metallic material and a second layer of a second metallic material using a continuous casting process, and continuously bonding the first and second layers to form a integrally cast multilayer metallic casting. The process may be performed using a twin-roll type continuous casting system having a continuous casting mold that includes a first mold compartment for receiving a molten first metallic material and a second mold compartment for receiving a molten second metallic. The molten first and second types of metallic material are gradually solidified into semi-solid shells and are pressed together by opposed casting rolls, creating a metallurgical bond between the first and second types of metallic material in order to form an integrally cast multilayer metallic casting. The process permits the large scale efficient manufacturing of near net shape multilayer metallic castings.

Abstract: A process of making a multilayer metallic casting includes steps of simultaneously forming a first layer of a first metallic material and a second layer of a second metallic material using a high speed continuous casting process, and continuously bonding the first and second layers to form a integrally cast multilayer metallic casting. The process may be performed using a twin-roll type continuous casting system having a continuous casting mold that includes a first mold compartment for receiving a molten first metallic material and a second mold compartment for receiving a molten second metallic. The molten first and second types of metallic material are quickly solidified into semi-solid shells and are pressed together by opposed casting rolls, creating a metallurgical bond between the first and second types of metallic material in order to form an integrally cast multilayer metallic casting. The process permits the high speed efficient manufacturing of near net shape multilayer metallic castings.

Abstract: A process of making a photovoltaic unit includes steps of simultaneously forming a first layer of n-type material and a second layer of p-type material using a continuous casting process, and continuously bonding the first and second layers to form a p-n junction. The process may be performed using a twin-roll type continuous casting system having a continuous casting mold that includes a first mold compartment for receiving molten n-type material and a second mold compartment for receiving molten p-type material. The molten n-type material and the molten p-type material are gradually solidified into semi-solid shells and are pressed together by opposed casting rolls, creating a metallurgical bond between the n-type material and the p-type material that forms an effective p-n junction. The process permits the large scale efficient manufacturing of photovoltaic units.

Abstract: A process of making a photovoltaic unit includes steps of simultaneously forming a first layer of n-type material and a second layer of p-type material using a continuous casting process, and continuously bonding the first and second layers to form a p-n junction. The process may be performed using a twin-roll type continuous casting system having a continuous casting mold that includes a first mold compartment for receiving molten n-type material and a second mold compartment for receiving molten p-type material. The molten n-type material and the molten p-type material are gradually solidified into semi-solid shells and are pressed together by opposed casting rolls, creating a metallurgical bond between the n-type material and the p-type material that forms an effective p-n junction. The process permits the large scale efficient manufacturing of photovoltaic units.

Abstract: An improved mold assembly for a continuous casting machine includes a mold liner assembly having an inner surface defining a casting space in which molten metal is shaped and cooled, an immersion nozzle, terminating within the casting space, for introducing molten metal into the casting space, and selective cooling structure for selectively cooling the mold liner assembly in such a manner that cooling is directed in varying intensities to different portions of the inner surface of the mold liner assembly according to predetermined circulation patterns in the molten metal, whereby heat transfer inequality as a result of convection is accommodated over the entire inner surface of the mold liner assembly.

Abstract: A roll for use in a continuous casting machine includes a roll body that is constructed and arranged to be mounted for rotation in a guide segment area of a continuous casting machine, and a generally cylindrical outer surface on the roll body. Preferably, the outer surface is fabricated at least in part from an age-hardenable nickel-based alloy that includes, in weight percent, up to 0.3% carbon, about 5% to about 12% chromium, and about 10% to about 30% molybdenum. The roll exhibits superior high temperature strength and stability, low thermal expansion, and superior oxidation resistance at temperatures that are typical during operation in a continuous casting machine. A process of making a metal casting using such a roll is also disclosed.

Abstract: An improved process of operating a continuous casting mold of the type that includes at least one mold surface and at least one coolant passage that is in thermal communication with the mold surface includes determining based on at least one factor whether it would be most advantageous to direct coolant through the coolant passage in a first direction or in a second, opposite direction. For example, if the mold liner is beneath a predetermined thickness it may be advantageous to circulate the coolant so that it enters the water jacket and the coolant slots that are defined in the mold liner at the bottom and exiting from the top so that there is some prewarming of the coolant before it reaches the meniscus region. Conversely, if the mold liner is thicker it may be desirable to introduce the coolant at the top of the water jacket, thus enhancing the cooling effect in the meniscus region.

Abstract: A method of initiating a continuous casting mold includes steps of positioning a plug inside a continuous casting mold, sealing the plug with respect to inner walls of the mold, positioning a prefabricated chill member on a top surface of the plug; and introducing molten metal into the mold. By prefabricating the chill member, valuable time is saved during the mold startup phase. The prefabricated chill member may have a compressible metallic sealing strip secured thereto to enhance sealing against the mold wall without abrading or scratching the mold wall. Another aspect of the invention involves sealing the gaps that exist between the mold surfaces and the mold plug by use of a an elongated body that defines in cross-section a broadened upper portion and a tapered lower portion that narrows into a leading edge. This construction permits the sealing element to be quickly inserted into a gap without being caught on the mold plug.

Abstract: A method of preparing a pouring tube such as a submerged entry nozzle (SEN) for use in a continuous casting machine includes steps of preheating at least one portion of the pouring tube by exposing the pouring tube to intensive radiative heat transfer; and installing the preheated pouring tube into a continuous casting machine. In the preferred embodiment the source of intensive radiative heat transfer is a high intensity infrared heat source that is capable of preheating the pouring tube to a temperature of up to 2000 degrees F. within seven to ten minutes. This compares with conventional gas preheating techniques that typically take over thirty minutes and thus require many steel producers to keep an SEN on constant preheat. By eliminating this necessity, the pouring tube may be prepared for use more quickly and in an environmentally sounder manner than through conventional preheating processes.

Abstract: An important liner for use in a continuous casting machine includes the conventional hot face surface, cold face surface, and at least one coolant interface area, such as the bottom of a cooling clot that is machined into the liner. Advantageously, the coolant interface area is configured to have a shape along at least a portion of its length that differs from the simple planar shape that is usual for such areas. This shape could include a fin that projects from the coolant interface surface, a corrugation, or other shape. As a result of this configuration, the surface area of the coolant interface area is maximized, thereby promoting enhanced heat transfer through the liner at a portion of the liner that is proximate the coolant interface area. This configuration can be placed selectively at certain areas of the mold that are felt to need increased thermal conductivity, such as near the meniscus area, and in areas where premature mold wear or cracking have been observed due to thermal stresses.

Abstract: An improved mold assembly for a continuous casting machine includes a mold liner assembly having an inner surface defining a casting space in which molten metal is shaped and cooled, an immersion nozzle, terminating within the casting space, for introducing molten metal into the casting space, and selective cooling structure for selectively cooling the mold liner assembly in such a manner that cooling is directed in varying intensities to different portions of the inner surface of the mold liner assembly according to predetermined circulation patterns in the molten metal, whereby heat transfer inequality as a result of convection is accommodated over the entire inner surface of the mold liner assembly.

Abstract: An improved guide segment assembly for a continuous casting machine includes a support frame and a guide segment that includes a bottom segment portion having a number of support rolls for engaging a bottom surface of a continuously cast strand, and a top segment having a number of guide rolls thereon for engaging a top surface of the strand. A force applicator is provided for urging the top and bottom segment portions toward one another against mechanical stops in order to provide support for the strand that is sufficient to counter ferrostatic pressure within the strand. A resilient mechanism is positioned between the support frame and the guide segment for permitting limited movement between the support frame and the guide segment during abnormal casting conditions. As a result of the resilient mechanism, both the support rolls and the guide rolls will be amply protected against overload conditions during abnormal conditions such as cold withdrawals.

Abstract: An improved mold for a continuous casting process includes an outer wall that has a plenum chamber defined in an inner surface thereof and at least one passage for communicating the plenum chamber with an external coolant conduit. The mold further includes a liner that is secured to the inner surface of the outer wall. The liner has a number of slots defined in an inner wall thereof which, together with the outer wall, define a number of passages for transporting coolant to cool the liner during operation of the mold. Each of the slots has a radiused transition portion that is proximate to a location where the slot communicates with the plenum. The transition portion decreases in cross-section as the slot approaches the plenum. The mold further includes a velocity plate that is positioned between the plenum and the transition portion to limit an opening by which coolant may flow between the plenum and the transition portion.

Abstract: An improved shroud tube supporting and changing apparatus for use in a bottom pour metal teeming operation includes an elongated arm having its midpoint mounted on the teeming vessel for free rotation about a generally vertical axis and for limited pivotal movement about a horizontal axis, and a shroud tube support on each end of the elongated arm for engaging and providing gimbal-like support for a shroud tube. A power actuator mounted on the teeming vessel is selectively operable to pivot the arm about the horizontal axis in one direction to maintain a fluid tight seal between the shroud tube and the bottom pour opening in the teeming vessel, and to permit the arm to be pivoted in the other direction to disengage the shroud tube from the bottom pour opening and permit the arm to be rotated about the vertical axis to place a new shroud tube in position beneath the bottom pour opening.