Hazelett Strip-casting Corporation

John F Wood

Robert William Hazelett

Robert J Carmichael

Timothy Dean Kaiser

Charles D Dykes

Jerome B Allyn

Charles R Simon

Frank E Kalaskie

Stanley W Platek

Gary P Ackel

Joseph C O'Kane

For closing gaps between blocks of a moving edge dam prior to its travelling downstream into the entrance of a moving mold defined between upper and lower revolving casting belts moving downstream from the mold entrance to its exit, the moving edge dam is initially elevated into a crest, as shown in FIGS. 12 and 14. This crest is above a plane generally defined by the lower casting belt travelling downstream. Then, a guide roller positioned above thrusts downwardly upon the moving edge dam bending it convex downwardly as shown at 'B' in FIG. 14 for causing its dam blocks to press against each other for sliding them along their high strength endless flexibile carrying member, thereby closing gaps between the blocks entering the mold entrance for sealing the entrance against outward leakage of molten metal between blocks. The downward convex bending also produces desired downward pressure of the moving edge dam against the lower casting belt, thereby enhacing sealing action between moving edge dam and lower belt. The downward thrust of this roller is sensed for indicating the amount of tension in the endless flexible carrying member of the moving edge dam. Back-breaker apparatus in rolling contact with a moving edge dam during its sagging return travel from mold exit to mold entrance has remotely controllable lift means for controllably raising or lowering the sagging edge dam for respectivley increasing or decreasing tension of the endless flexible carrying member.

Edge dam tensioning and sealing method and apparatus for twin-belt

A method and system are provided for synchronizing the travelling edge dams in the continuous casting of metal slab, strip, or bar, thereby providing a means for the continuous uniform casting of longitudinally spaced edge shapes, contours, or profiles such as integral shoulders, lugs, lobes, depressions, curves, or indentations in the opposite edges of the cast product. Shapes include the protruding lugs, cast directly opposite each other, for suspending copper anodes in electrolytic refining-also the intruding, material-saving contours in the tops of anodes. A belt-type continuous casting machine is shown wherein two moving contoured edge dam loops each comprise blocks strung upon flexible endless metal straps. The moving edge dams on each side of the mold must be synchronized, regardless of disturbing thermal variations notably. 'Back breakers' exert upward rolling contact force controllably and separately against each moving edge dam loop along its return path, thereby changing the local curvature and so adjusting the degree of mutual compression and closeness of the constituent dam blocks or the end-to-end spacing of the same. Such compression effectively shortens the elevated edge dam loop and thereby hastens its revolutions. Known previous methods of heating or cooling to synchronize the edge dam loops may advantageously be used in addition to back-breaker control. The positioning of separate 'back-breaker' apparatus in an inverted configuration near the entrance to the moving mold results in a significant improvement in the sealing capability of the entering edge dams against the lower casting belt where molten metal is introduced.

Edge dam synchronization and tensioning control method and system for

Systems are provided for continuously casting metal product directly from molten metal confined and solidified in a casting region defined by upper and lower, cooled, endless, flexible, traveling, casting belts supported by belt support systems including back-up rollers in respective upper and lower carriages and laterally defined by first and second traveling side dams. The back-up rollers and belt support systems shape and maintain the casting region for improved heat transfer between cast metal and belts for improved product uniformity and enhanced machine performance. Several systems are disclosed including having one belt flexibly constrained, resulting in a transverse bowing away from the casting centerline due to liquid metal head, with the opposing belt being rigidly constrained and contoured or transverselybowed towards the casting centerline in a configuration that compensates for displacement of the flexibly constrained belt resulting in a uniform transverse cross section. Systems are disclosed including bowing the upper back-up rollers down either by manual adjustment or remote control and at the same time allowing the lower rollers to yield; intentionally rigidizing the upper and/or lower back-up rollers or sections thereof; bowing both sets of back-up roller in equal and opposite directions, bowing the rollers inward or outward using either manual adjustment or remote control tensioning; bending structural frame members which are in support relationship with rollers, thus maintaining predetermined configurations of rollers in contact with the belts and further including downstream tapering of the casting region.

Systems for shaping the casting region in a twin-belt continuous casting

Methods for continuously casting metal product directly from molten metal confined and solidified in a casting region defined by upper and lower, cooled, endless, flexible, traveling, casting belts supported by belt support systems including back-up rollers in respective upper and lower carriages and laterally defined by first and second traveling side dams. The back-up rollers and belt support systems shape and maintain the casting region for improved heat transfer between cast metal and belts for improved product uniformity and enhanced machine performance. Several methods are disclosed including having one belt flexibly constrained, resulting in a transverse bowing away from the casting centerline due to liquid metal head, with the opposing belt being rigidly constrained and contoured or transversely bowed towards the casting centerline in a configuration that compensates for displacement of the flexibly constrained belt resulting in a uniform transverse cross section. Methods are disclosed including bowing the upper back-up rollers down either by manual adjustment or remote control and at the same time allowing the lower rollers to yield; intentionally rigidizing the upper and/or lower back-up rollers or sections thereof; bowing both sets of back-up rollers in equal and opposite directions, bowing the rollers inward or outward using either manual adjustment or remote control tensioning; bending structural frame members which are in support relationship with rollers, thus maintaining predetermined configurations of rollers in contact with the belts and further including downstream tapering of the casting region.

Methods for shaping the casting region in a twin-belt continuous casting

The casting belt is preheated with steam closely ahead of the entrance to the casting zone by providing wrap-around steam feed tubes having nozzles, such tubes being positioned in very deep circumferential grooves in input pulley or nip pulley which moves the casting belt into the input end of the casting zone. These circumferential grooves of the input or nip pulley also house wrap-around liquid coolant feed tubes for cooling the casting belt near the beginning of the casting zone. The wrap-around steam feed tubes also have radial ports positioned to direct steam toward the reverse side of the endless belt, with the port being spaced from the nozzle thereby providing a staged elevation of temperature in the flexible casting belt on the input or nip pulley, while the belt is in contact therewith before the belt reaches the casting zone. Elevating the temperature prior to the endless belt reaching the casting zone and then suddenly cooling the belt when the molten metal is applied thereto improves casting conditions in the operation of such thin, flexible casting belt and enhances and speeds up the casting process. There are several ways for preventing coolant water from cooling the steam header and tubes of the bottom nip pulley in a twin-belt machine.

Method of and apparatus for steam preheating endless flexible casting

An improvement in continuous metal casting machines of the type having a pair of flexible, moving casting belts which revolve along endless paths for defining a casting region therebetween and moving side dams which revolve along with the casting belts for confining the cast strip, slab or bar laterally. The casting belts are individually supported by upper and lower carriage means. The machine is provided with sensors such as load cells for sensing the displacement forces existing between the upper and lower carriages at selected points along the path of belt travel, and for sensing the side pressures exerted upon the side dams by the cooling, solidifying metal. This sensing permits the maintenance of predetermined, desired contact pressures along the length of the solidifying metal to thereby improve the physical characteristics of the cast product. The sensor outputs may be utilized to manually adjust the pressure points or, alternatively, may be employed in an automatic feedback system for providing automatic control of the various casting parameters affecting mold contact pressures and pressure distribution.

Method and apparatus for continuous casting of metal under controlled

Method and apparatus are described for continuously casting metal slab, strip or bar with integral lugs projecting therefrom. These lugs project from the edge of the cast product and lie in the casting plane, but they have a partial thickness as compared with the thickness of the product. Continuous wide slabs of unrefined copper or other electrolytically refinable metal having partial thickness lugs on both edges can be cut to form electrode plates for subsequent refining by suspending in an electrolytic bath. These partial thickness lugs serve as supports and provide electrical connection from the side rails of the electrolytic cell. Their partial thickness conserves metal and weight. In the continuous casting method and apparatus the revolving edge dams include special dam blocks defining partial thickness mold pockets for casting the integral lugs. Synchronization of lug positions along opposite edges of the cast product is maintained by controllably changing the relative temperatures of the revolving edge dams with respect to each other, for example, by relatively increasing the cooling of one of the revolving edge dams when it tends to lag the other, thereby relatively decreasing its length and increasing its rate of revolving, or, for example, by relatively decreasing the cooling of one when it tends to lead the other, thereby relatively increasing its length and decreasing its rate of revolving.

Method and apparatus for continuously casting metal slab, strip or bar

Continuous casting apparatus is described wherein the temperature of the flexible casting belts in twin-belt machines having two or more main rolls in each belt carriage is controllably elevated prior to contact with the molten metal to improve the casting conditions and the operation of the thin flexible casting belts; the temperature elevation preferably being relatively gradual may be carried out while the travelling belts are approaching the nip rolls or while the belts are in contact with the nip rolls, or both. Zone control of belt pre-heating is disclosed, and control of the coolant streams issuing from the curved nip roll tubes by use of fingernail-like extenders may be provided to aid in pre-heating the belts and in controlling their operation. Intensive infra-red heaters are shown directed at close range toward the casting surfaces of the belts, these heaters serving also to cure and dry any coating material on the belts. Heating of the nip rolls by means of hot fluid, such as steam, is described, with the hot fluid being directed into the interior of the nip roll or being directed into the deep grooves in the nip roll beneath the rear surfaces of the casting belts. Mechanical and thermal sensors may be employed to sense the distortion of the belts and to measure their operating temperatures, these sensors being shown with automatic control of the belt pre-heating action. The apparatus of the invention can be applied to twin-belt casting machines regardless of whether the molten metal is supplied by open pool, closed pool or injection feeding.

Coolant nozzle apparatus in twin-belt continuous casting machines

Continuous casting methods and apparatus are described wherein the flexible casting belts in twin-belt machines having two or more main rolls in each belt carriage are sensed by mechanical probes, and belt temperatures are controllably elevated prior to contact with the molten metal to improve the casting conditions and the operation of the thin flexible casting belts; the temperature elevation preferably being relatively gradual may be carried out while the travelling belts are approaching the nip rolls or while the belts are in contact with the nip rolls, or both. Zone control of belt pre-heating is disclosed, and control of the coolant streams issuing from the curved nip roll tubes by use of fingernail-like extenders may be provided to aid in pre-heating the belts and in controlling their operation. Intensive infra-red heaters are shown directed at close range toward the casting surfaces of the belts, these heaters serving also to cure and dry any coating material on the belts. Heating by means of hot fluid, such as steam, is described, with the hot fluid being directed into the deep grooves in the nip roll beneath the rear surfaces of the casting belts. Mechanical and thermal sensors are employed to sense the distortion of the belts and to measure their operating temperatures, these sensors being shown with automatic control of the belt pre-heating action. The methods and apparatus of the invention can be applied to twin-belt casting machines regardless of whether the molten metal is supplied by open pool, closed pool or injection feeding.

Twin-belt continuous casting wherein the belts are sensed by mechanical

Continuous casting apparatus wherein the temperature of the flexible

A symmetrical belt-steering and tensioning system and apparatus for twin-belt continuous metal casting machines are disclosed. A rigid squaring shaft passes through a hollow tension and steering roll and is rigidly secured to torque arms at opposite ends of the roll assuring that this roll remains parallel with the driving roll at the other end of the carriage throughout the range of tensioning travel, these arms each being associated with tension thrust means and steering means. The geometrical relationships assure that tension in the casting belts remains essentially directly proportional to the fluid pressure in the thrust cylinders, while a pre-loading arrangement removes back lash from the pivots to improve steering precision and also provides mechanical advantage. A symmetrical synchronized steering action is applied to both ends of the tension-steering roll, and axial thrust control means operate to force the roll skewing movement to center at a predetermined point. Independent adjustment of the displacement of each end of the tension-steering roll from the pass line is provided by sleeves associated with the squaring shaft and bearings in the interior of the hollow roll. A high belt tension force can be applied because there are two main large diameter rolls at opposite ends of each carriage defining the belt path as a symmetrical oval shape. Wide casting belts of 116 inches in width or more are precisely steered and tensioned for continuously casting slabs 100 inches or more in width.

Symmetrical synchronized belt-steering system and apparatus for

A symmetrical belt tensioning system and apparatus for twin-belt continuous casting machines are disclosed. A rigid squaring shaft passes through a hollow tension roll and is rigidly secured to torque arms at opposite ends of the roll assuring that this roll remains parallel with the driving roll at the other end of the carriage throughout the range of tensioning travel, these arms each being associated with tension thrust means. The geometrical relationships assure that tension in the casting belts remains essentially directly proportional to the fluid pressure in the thrust cylinders, while a pre-loading arrangement removes back lash from the pivots to improve steering precision and also provides mechanical advantage. Independent adjustment of the displacement of each end of the tension-steering roll from the pass line is provided by sleeves associated with the squaring shaft and bearings in the interior of the hollow roll. A high belt tension force can be applied because there are two main large diameter rolls at opposite ends of each carriage defining the belt path as a symmetrical oval shape. Wide casting belts of 116 inches in width or more are precisely steered and tensioned for continuously casting slabs 100 inches or more in width.

Symmetrical belt tensioning system and apparatus for twin-belt

Continuous casting methods are described wherein the temperature of the flexible casting belts in twin-belt machines having two or more main rolls in each belt carriage is controllably elevated prior to contact with the molten metal to improve the casting conditions and the operation of the thin flexible casting belts; the temperature elevation preferably being relatively gradual may be carried out while the travelling belts are approaching the nip rolls or while the belts are in contact with the nip rolls, or both. Zone control of belt pre-heating is disclosed, and control of the coolant streams issuing from the curved nip roll tubes by use of fingernail-like extenders may be provided to aid in pre-heating the belts and in controlling their operation. Intensive infra-red heaters are shown directed at close range toward the casting surfaces of the belts, these heaters serving also to cure and dry any coating material on the belts. Heating by means of hot fluid, such as steam, is described, with the hot fluid being directed into the deep grooves in the nip roll beneath the rear surfaces of the casting belts. Mechanical and thermal sensors may be employed to sense the distortion of the belts and to measure their operating temperatures, these sensors being shown with automatic control of the belt pre-heating action. The methods of the invention can be applied to twin-belt casting machines regardless of whether the molten metal is supplied by open pool, closed pool or injection feeding.

Growing community of inventors

Burlington, VT, United States of America

John F Wood