US3041686A - Cooling methods and apparatus for providing a rapidly moving uniform layer of liquidcoolant - Google Patents

Description

July 3, 1962 R. w. HAZELETT ET AL COOLING METHODS AND APPARATUS FOR PROVIDING A RAPIDLY MOVING UNIFORM LAYER OF LIQUID COOLANT Filed Dec. 21, 1959 3 Sheets-Sheet 1 July 3, 1962 R. w. HAZELETT ETAL 3,041,686

COOLING METHODS AND APPARATUS FOR PROVIDING A RAPIDLY MOVING UNIFORM LAYER OF LIQUID COOLANT Filed Dec, 21, 1959 3 Sheets-Sheet 2 INVENTORS Robert William Hozelefi BY Richard Hozele'rr y 1962 R. w. HAZELETT ETAL 3,041,686

AND APPARATUS FOR PROVIDING A RAPIDLY coomuc METHODS- MOVING UNIFORM LAYER 0F LIQUID COOLANT I Filed Dec. 21, 1959 5 Sheets-Sheet 5 IN VEN TORS Robert Willi Hczele'rr BY Rich Huzelert United States Patent 3,041,686 COOLING METHUDS AND APPARATUS FOR PRO- VIDING A RAPELY MOVING UNEORM LAYER 0F LIQUID COOLANT Robert William Hazelett, Malletts Bay, and Richard Hazelett, Winooski, Vt., assignors to Hazelett Strip- Casting Corporation, Winooski, Vt.

Filed Dec. 21, 1959, Ser. No. 861,134 16 Claims. (Cl. 2257.4)

This invention relates to cooling methods and apparatus for providing a rapidly moving uniform layer of liquid coolant adapted to withdraw large quantities of heat from a surface along which the layer of coolant is applied.

The invention is described as embodied in a casting machine in which a molten material such as moltenmetal is confined in a region between two spaced substantially planar surfaces moving along together and formed by a pair of endless casting belts. The cooling apparatusprovides rapidly moving uniform layers of liquid coolant travelling along the outer surfaces of these two belts, thus cooling the belts for solidifying the molten metal between them. As the solidified metal is discharged from between the casting belts, further molten metal is introduced between them in a continuous casting process, as described in our prior copending application Serial No. 722,005.

In order to support and guide the moving casting belts while at the same time exposing their outer surfaces to the rapidly moving layers of coolant, there are a large number of narrow fin-like supporting elements in engagement with the outer surfaces of the belts. The rapidly moving layers of coolant travel along the surfaces of the belts between these narrow supporting elements. For preventing deflections or bending in the belt, it is desirable to have these supporting elements positioned close together, and nevertheless there must be sufficient room between them to enable the coolant to be applied to the belt and the excess coolant to be removed therefrom. It is one of the advantages of this invention that it enables the rapidly moving layer of coolant to be applied and the excess coolant to be removed conveniently and easily while enabling the supporting elements to be positioned close together.

By virtue of the fact that the present invention assures adequate cooling while enabling the supporting elements to be positioned close together, an increased pressure or hydrostatic head can be applied to the molten metal between the belts, which is desirable for certain continuous casting processes.

Inthe illustrative embodiment of the present invention described herein the liquid coolant is applied to the outer surface of each belt as a continuous uniform sheet of liquid which converges with the surface of the belt at a slight angle. As this uniform sheet of coolant impinges upon the surface of the belt it immediately forms a uniform continuous layer of coolant travelling along the surface of the belt. For creating this uniform sheet, the coolant is initially discharged at a slight angle against a coolant application guide which smooths out the coolant and then guides the coolant along a curved path which is tagential with the desired final direction of travel, which is then at a slight angle with respect to the surface of the belt.

In this embodiment of the invention combined coolant application guides and scoopsare provided for creating and precisely controlling the rapidly moving layer of coolant. The coolant is guided along its curved path by means of a curved guide surface extending along one side of each combined guide and scoop, and a scoop surface extends along its other side for removing excess coolant earnest Fatented July 3', 1962 ice '2 from the cooled surface before additional coolant is applied.

It is an advantage of the present invention that the coolant is formed into a uniform continuous sheet before the coolant impinges upon the surface to be cooled, thus assuring a uniform cooling action over the cooled surface.

A further advantage results from the fact that a coolant application guide surface is utilized to shape the coolant into a thin uniform continuous sheet, and the use of narrow slit-like orifices is avoided.

The various features, aspects, and advantages of the present invention will be more fully understood from a consideration of the following description of continuous casting apparatus incorporating the invention, considered in conjunction with the accompanying drawings, in which:

FIGURE 1 is a longitudinal elevational sectional view of continuous casting apparatus embodying the cooling methods and apparatus of the present invention;

FIGURE 2 is a transverse sectional view taken along the line 22-of FIGURE 1;

FIGURE 3 is a partial perspective view of a combined coolant application guide and coolant scoop illustrating certain features of operation; and

FIGURE 4 is a sectional view, on enlarged scale, of a combined coolant application guide and scoop, illustrating further details of construction and operation.

In the continuous casting apparatus of FIGURES l and 2, the molten metal 10 to be solidified into a continuous strip or slab 11 is introduced in the direction of the arrow 13 into a casting region C between a pair of thin, wide flexible belts or bands 12 and 14. The casting region is defined by planar portions of these belts travelling along at substantially the same speed in spaced faceto-face relationship, as indicated by the arrows applied to the portions of the respective belts shown in FIGURE 1. The over-all construction and operation of a casting machine having a pair of casting belts such as shown here are described in detail in the prior copending application No. 722,005, to which reference is directed. However, certain aspects of the construction and operation of this type of casting machine are summarized here as being particularly pertient to the field of this invention. The thickness of the strip being cast is determined by the spacing between the belts 12 and 14, and the width of the cast strip is controlled by the lateral spacing between a pair of spaced moving edge dams, one being shown in FIGURE 2 by reference 15. These moving edge dams 15 fit between the edges of the casting belts, and they may have a construction as described and claimed in US. Patent" No; 2,904,860, issued on September 22, 1959.

The casting belts 12 and 14 are formed of flexible and heat resistant sheet metal having a relatively high tensile strength, for example, conventional cold-rolled low carbon sheet steel having its ends welded together. Both surfaces of the weld are ground smooth and flush to form a continuous wide band or belt. These belts are relatively wide and thin, for example, having a width of the order of 46 inches and having a thickness lying in the range from 0.0 15 to 0.035 of an inch.

In order to support and guide the casting belts 12 and 14-, a large number of narrow fin-like supporting elements 16 are positioned in engagement with the outer surfaces of each of the belts. As shown, these supporting elements are provided by high, thin ridges on a plurality of closely spaced parallel back-up rollers 18 extending transversely across the outer surfaces of the casting belts, and rotatably mounted by means of end bearings 19 on main side frames 21.

Rapidly moving layers of coolant 20 and 22 are created and maintained travelling along the outer surfaces of the belts 12 and 14, passing between the narrow sup- I speed.

porting elements These layers of coolant withdraw 7 large quantities of heat per. unit time from the casting belts and thus cool and solidify the molten metal Ill becoolant collection gutter 32. The rear face 34 of the rigid member 28 forms a coolant application guide 'surface, and the front face 36 forms a coolant scoop and diverting surface. The coolant is supplied from a large tank, as will be understood from the prior application mentioned above, and is pumped under substantial pressure into each of the large diameter conduits 26. Each of these conduits has a plurality of aligned nozzles 38 connected thereto for discharging jets 39 of the cool-ant.

In this example, the coolant is water containing a suitable rust inhibitor, for example, such as sodium chromate added in a concentration of 6.7 ounces per 100 gallons 7? of'water. The coolant layers 20 and 22 in FIGURE 1 are shown rapidly travelling longitudinally along the outer surfaces of the respective belts 12 and 14'toward the right, in the same direction as these belts are moving but it will be understood that the coolant layers are moving many, many times faster than the belts. As these coolant layers scrub along the surfaces of the belts, they become slowed down by the frictional drag, and it is necessary to re-accelerate them periodically up to their Speed film of coolant adjacent to the surface of each belt. The combined coolant application guide and scoop units initial speed so as to obtain the desired continuous high- 2'4 periodically re-accelerate these coolant layers,

the units 24 also serve to remove excess coolant from the layers20 and 22 before re-accelerating them. As

the coolant layers strike against the sharp leading edges 40 of the coolant scoop surfaces 36, the outermost portion of the respective coolant layer is diverted and a coolant layer 20 or 22 of reduced thickness continues scrubbing along thev belt surface, such as the reduced layer 20', seen. most clearly in FIGURE 4. ,In effect, this sharp leading edge 40 forms the toe of the foot portion 301 of the rigid member28; The thinner coolant layer which passes beneath the foot portion has less inertia than the original thicker layer, and thus it is re-accelerated more suitably.

As illustrated, the leading edge. 40 of each scoop 'extends across substantially the entire width of the belt, and this edge 40 is spaced a uniform distance from the outer surface of the belt. For example, in this embodiment of the invention. the spacing between the outer surface of For purposes ofre-accelerating the coolant layer, :a substantially continuous. free-travelling sheet 42 of coolant is directed at a slight angle A towar-d the outer surface .of Each belt. This free-travelling sheet impinges upon the respective reducedthickness coolant layer 20' 'or 22', merges with it, and thus rc-accelerates it to the desired Itwill be :appreciated that each free travelling coolant-sheet 42-extends for substantially the entire width of the layer of coolant 20 or 22. Consequently, 'a uniform acceleration action forthe-coolant layer is provided across-the entire widthof thebasting region.

and cleanly from the under-surface of'the foot portion I dence and become spread out and flattened into an initial rapidly moving' layer 43, against the upper part of the application guide surface. This upper part of the application guide surface is planar so as to produce a substantiahy uniform layer 43. After the jets of coolant have become flattened out into the initial layer 43, then this initial layer of coolant is guided around a curve 44' at the,

heelof the foot portion 30.. This'curve 44 is tangential with a final straight edge portion 46 which is aimed at theslight angle A with respect to the surface of the belt 12. From this edge pontion46 the free-travelling sheet '42 of liquid is shot out and converges with the reduced coolant layer 20' at the slight angle A.

. The free-travelling coolant sheet 40 is substantially uniform in thickness and velocity extending across the Width of the coolant layer 20'. This sheet 40 impinges into the reduced thickness layer of coolant 20' which has passed beneath the foot 30 ofthe member 28 and re-accelerates the coolant layer up to the desired speed and thicknes so as to recreate the rapidly moving layer 20.

It is important to arrange the jets 39 and the upper planar portion of the guide surface 34 such that the initial coolant layer 43 'becames fully flattened out and of uniform thickness across the width of the casting region C before the layer 43 reaches the curve 44. As shown in FIGURE 2, the jets 39 have become diverged laterally so as to cover the full Width of the guide surface 34 before they encounter the curve 44. The reason for this requirement of uniformity in thickness before the coolantlayer 43 reaches the curve 44 is the centrifugal force whichacts upon the layer 43 as it passes around curve 44. If there are thicker regions in this layer 43, then the centrifugal force causes these thicker regions toaccelerate laterally, pushing neighboring portions of the coolant'aside, and causing voids axes of each of the nozzles, and they operate to prevent the -building up of thicker regions in the layer 43. These vanes extent along the curve 44 and out to the edge portion 46 and also extend-upwardly along the planar area of the guide surface 34 above the level at which adjacent diverging regions 48would otherwise meet one another. Suchsmoothing vanes are not always essential to good operation when the nozzles are spaced and aimed so that the edges of the diverging regions 48 merge together to create a substantially uniform layer 43. However, these smoothing vanes become increasingly important when the coolant speed is increased.

It has been found that the'slight angle A and the slight angle 13 for impingementof the coolant are both critical and should be approximately equal. When the angle A is increased above 10", the free-travelling sheet 42 tends to su'ike'too hard against the surfaceof the reduced layer 20' so that the coolant bounces or ricochets off from the belt with resultant loss of cooling action and failure to produce the desired continuous scrubbing ac tion over the entire outside surface area of the belt adjacent to the casting region C. Accordingly, the angle A should be 110 more than 10. Conversely, if the free- ;travelling sheet 42 is aimed too closely parallel with the minished because the sheet 42 will travel too far through the atmosphere before merging into the coolant layer 20. The best results have been obtained using an angle A of approximately 6, that is, within one degree either side of 6. In this particular example, the angle A is shown Similarly, the angle B at which the jets 39 impinge upon the planar area of the guide surface 34- should be no more than 10 to prevent the coolant jets from bouncing or ricocheting therefrom. The angle B must be suflicient, however, to assure the complete divergence of the jets over the full active width of the guide surface 34 before the coolant encounters the curve 44, for reasons discussed above. The optimum value for the angle B has been found to be very nearly the same as that for the angle A. For units having the construction as shown in this example, the angle B is also approximately 6, that is within one degree either side of 6.

It will be appreciated that the methods and apparatus of the invention enable the rows of rotatable tin-like ele ments 16 to be closely positioned for preventing deflection or sagging of the belt under the pressure of the molten metal. The clearance space is advantageously reduced to a value less than 60% of the diameter of the rotatable elements 16. In this example the diameter of the elements 16 is 2% inches and the clearance space is only 1% inch, thus being 56% of the diameter. Accordingly, the points of rolling engagement 51 between the elements 16 and the belt are spaced longitudinally along the belt no more than 3 /2 inches, thus providing closely spaced points 51 of support for the belt.

As mentioned previously, the outermost portion of the coolant layer is diverted by the sharp leading edge 40 of the scoop and thus travels upwardly along the scoop surface 36 under its own momentum. For purposes of reducing the frictional drag upon this diverted coolant 52, a plurality of abrupt step- like breaks 53, 54, and 55 are provided in the scoop surface 36. Consequently, the extent of the wetted surface is reduced as the diverted coolant 52 breaks away from the scoop surface and shoots up into the converging mouth 56 of the collection gutter 32. As the coolant enters the gutter, a plurality of skewed deflector vanes 58 cause the coolant to change direction and to travel longitudinally along the gutter, thus returning to the pumping system, which again supplies the conduits 26.

In order to provide accurately aligned nozzles 38 which are uniformly spaced one-half inch on centers, it is advantageous to use the construction as shown. A nozzle block 60 is rigidly secured to the top of the member 28 by means of a plurality of machine screws 61. This member 28 has an alignment shoulder 62 and a mounting surface 63 which is perpendicular to the surface of the belt 12 and against which the nozzle block is clamped. A central recessed area 64 extends along the side of the nozzle block adjacent to the mounting surface 63 for improving the fit between the block 66 and this mounting surface.

The nozzles are provided by stainless steel inserts having a flange 66 which seats down against the top surface of the mounting block. A socket in each flange accommodates an O-ring 68 which seats up against a flat face 70 on the conduit under the pressure of a series of clamping screws 72 that extend freely up through the nozzle block. A ledge 74 along the back edge of the nozzle block engages the conduit along. a line on the opposite side of the screws 72 from the O-rings 68, thus imposing the clamping thrust squarely on the O-rings. There are a series of openings 7 6 in the conduit which are aligned with the respective bores of the nozles. In this example these openings 76 have a diameter of of an inch, and the bores of the nozzles are of an inch long and taper from a diameter of 4 down to A3 of an inch. As shown, the conduit 26 has an inside diameter of 2 /2 inches and is an aluminum extrusion, and the nozzle The planar area of the guide surface is shown as extend ing downwardly a distance of 2% inches below the blockmounting shoulder 62, and the radius of the curve 44 is of an inch. The coolant discharge edge portion 46 is advantageously positioned closely adjacent to the surface of the belt so that the free-travelling sheet of coolant 42 travels through the air only a short distance before merging into the coolant layer on the casting belt. For example, this discharge edge 46 is here shown as spaced only a distance of of an inch from the surface of the casting belt. This position of the discharge edge closely adjacent to the casting belt assures that the free-travelling sheet 42 engages the coolant layer on the belt without any substantial. change in its uniform thickness after leaving the discharge edge.

in order to provide convenient access for cleaning out the conduits 26, a removable plug 78 (FIGURE 2) fits into one end of each conduit. Each plug is encircled by an annular channel 79 with an O-ring 8t seated therein for sealing up the end of the conduit, and mounting screws 82 secure the conduit in place. A threaded socket 83 in the exposed end of the plug is adapted to receive the end of a bolt or a threaded rod so as to provide a handle grip for withdrawing the plug, if an occasion should arise for cleaning out the conduit. It will be understood that the opposite end of each conduit is connected through a suitable duct to the pumping system which supplies the liquid coolant.

The coolant application guide and scoop units 24 are each secured to the side frame members 21 by means of a pair of machine screws 84, and a similar mounting arrangement is provided at the opposite end of each unit.

From the foregoing it will be understood that the cooling methods and apparatus of the present invention de- 7 scribed above are well suited to provide the advantages set forth, and since many possible embodiments may be made of the various features of this invention and as the method and apparatus herein described may be varied in various parts, all without departing from the scope of the invention, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense and that in certain instances, some of the features of the invention may be used without a corresponding use of other features, all without departing from the scope of the invention.

What is claimed is:

1. In the art of casting molten metal while the molten metal is constrained by a moving casting belt, the method of creating a rapidly moving uniform layer of liquid coolant travelling along the surface of the casting belt over an area to be cooled comprising the steps of ejecting a plurality of parallel jets of the liquid coolant, impinging said jets at a slightangle against a guide surface spaced from the surface of the belt and extending near to the surface of the belt, diverging said jets laterally across said guide surface to form an initial layer of coolant covering the guide surface and travelling along the guide surface, discharging said initial layer of coolant from said guide surface as a free-travelling sheet of coolant travelling over the space between said guide surface and the casting belt, and impinging said free-travelling sheet of coolant at a slight angle against the surface of the casting belt for creating said rapidly moving uniform layer of liquid coolant travelling along the surface of the casting belt.

2. In the art of casting molten metal in a casting region coolant travelling along a surface of the moving mold to be cooled comprising the steps of ejecting a plurality of parallel jets of the liquid coolant, impinging said jets at a edge, whereby asheet of the liquidcoolant is discharged slight angle against a guide surface, diverging said jets laterally across said guide surface to form' an initial substantially uniform layer, guiding said initial layer aroundta curve so that said initial layer is travelling at a slight angle toward said layer of coolant travelling along the surface'to be cooled, discharging said initial layer of coolant from said guide surface as a'substantially uniform free-travelling sheet of coolant moving through the space behind said guide surface, and impinging said free-travelling sheet'of coolant at a slight angle against the existing layer of coolanttravelling along the surface to be cooled for rte-accelerating said existing layer of coolant.

V 3. In the art'of continuous casting of molten metal wherein the metal is confined by a moving flexible oastlayer, impinging said jets at substantially grazing incidence against a guide surface, allowing said jets to diverge laterally across said guide surface to form an initial substantially uniform layer travelling along the guide surface, reversing the general direction of said initial layer by-guiding said initial layer around a curve until said initial layer is travelling in a direction at substantially grazing incidence with respect to the'desired direction of the coolant layer on the outside surface of the belt, discharging said initial layer as a free-travelling sheet of coolant passing through a space, and impinging said sheet of coolant at grazing incidence against the outside surface of the casting belt for creating said rapidly moving layer of liquid ooolantQ V 4. A method of cooling a heated belt, such as a moving casting belt of ametal casting machine, by means of a rapidly moving layer of liquid coolant travelling along the 7 surface of the casting belt which comprises establishing a rapidly moving layer of coolant on such belt, removing a substantial proportion of the liquid of the layer 7 at a position where such layer has become decelerated so as to leave a layer of reduced thickness, reaccelerating such reduced layer and re-establishing it to its original thickness by projecting a free-travelling sheet of coolant from said discharge edge as a free-travelling sheet travelling across said small distance and impinging onto the casting belt to form the rapidly moving layer of coolant travelling along the surface of the casting belt.

6. in the art of continuous casting of molten metal wherein the metal is confined by a continuous moving casting belt,-the method of creating a rapidly moving unconfinedlayer of liquid coolant travelling over the surface of the casting belt throughout an area to be cooled comprising the steps of ejecting a plurality of spaced jets of the liquid coolant onto a guide surface, diverging said jets laterally to cover the guide surface with a rapidly moving unconfined layer of the coolant, curving said layer around a bend, discharging said layer of coolant from the guide surface along an edge spaced a small distance from the casting belt, travelling said discharged layer as a free sheet moving across said small distance toward the casting belt, and converging said travelling layer with the surface of the casting belt to form the rapidly moving unconfined layer of coolant thereon.

7. In a casting machine of the type wherein molten metal is cast into metal strip by confining the molten metal between a pair of moving flexible belts having portions travelling in spaced face-to-face relationship defining a casting region between said belts, and wherein the belts are supported by rows of fin-like elements engaging the outer surface of each belt, a plurality of coolant application and scoop units for applying a rapidly moving layer of coolant to the outer surface of each belt, each of said units including a coolant collection gutter, coolant conduit means, and a rigid member extending along between adjacent rows of 'said elements,

said memberhaving a leg shape as seen in cross section tion surface extending along one face thereof terminatagainst said reduced layer in the direction of the liquid coolant flow at a position close to the removal position, saidfree-travelling sheet of coolant being substantially uniform across its width and extending substantially across said layer of coolant, said removal and said projection of a free-travelling sheet of coolant being repeated at intervals lengthwise of the direction of travel of the prising coolant application means having a guide surfacev extendingnear to the casting belt and terminating in a discharge edge which is spaced a small distance from the casting belt and is directed toward'the casting belt in the direction of'fiow of said rapidly moving coolant layer, a coolant conduit for the liquid coolant, a plurality of nozzles connected with said conduit for providing a plurality of jets'of the liquid coolant, said nozzles being ing in a coolant discharge edge at the heel of the foot portion, said'coolant discharge edge being aimed at a slight angle toward the outer surface of the casting belt, said coolant conduit means having nozzle means connected therewith and aimed at a slight angle toward said coolant application surface, said member having a coolant scoop surface extending along the other face thereof {from a leading edge at the toe of the foot pontion, and said collection gutter being arranged to receive coolant from said scoop surface.

, 8; A method of cooling a heated belt, such as a'moving casting belt of'a metal casting machine, by a rapidly moving layer of liquid coolant travelling along the surface of the casting belt comprising establishing a rapidly moving layer of coolant on such belt, removing a substantial proportion of the liquid of the layer at a position where such layer has become decelerated so as to leave a layer of reduced thickness, reaccelerating such reduced flow therein at a position close to the removal position,

said free-travelling sheet of coolant being substantially uniform across its width and extending substantially aimed toward said guide surface, said liquid jets imping- 1 ing on said guide surface for diverging said liquid jets into a layer of coolant covering the guide surface and acrosssaid layer of coolant, said free-travelling sheet of 'coolant being created by ejecting a plurality of parallel jets directed'at a large angle relative to the direction of travel of the coolant layer and impinging such jets onto a guidesurface, said jets being so spaced and so positioned in relation to the guide surface as to spread thereover to form a substantially uniform initial layer of coolant on the guide surface, guiding said initial layer around a curved portion of said guide surface to assume the direction of travel of said free-travelling sheet, and discharging coolant in the form of said free-travelling sheet from an edge of said guide surface.

9. In a continuous casting machine of the type wherein molten metal is solidified while being retained by a moving casting band, and wherein the band is supported by rows of narrow elements in engagement therewith, a plurality of coolant application and scoop units for applying a rapidly moving layer of coolant to a surface of the casting band, each of said units including a coolant collection gutter, coolant conduit means, and a rigid member extending along between adjacent rows of said elements, said member having a first and a second side and having a leg shape as seen in cross section with an enlarged foot portion near to the surface of the casting band, said member having a coolant application surface extending along said first side thereof toward the casting band and terminating in a coolant discharge edge at the heel of the foot portion, said coolant discharge edge being aimed at a slight angle towardthe surface of the casting band, said coolant conduit means having orifice means connected therewith and aimed at a slight angle toward said coolant application surface, said member having a sharp leading edge at the toe of said foot portion with a coolant scoop surface extending along said second side thereof from said leading edge, and said collection gitter being arranged to receive coolant from said scoop surface.

10. In a continuous casting machine of the type wherein molten metal is solidified while being retained by a moving casting band, and wherein the band is supported by rows of narrow elements in engagement therewith, a plurality of coolant application and scoop units for applying a rapidly moving layer of coolant to a surface of the casting band, each of said units including a coolant collection gutter, coolant conduit means, and a rigid member extending along between adjacent rows of said elements, said member having a first and a second side and having a foot portion near to the surface of the casting band, said member having a coolant application surface extending along said first side thereof toward the casting band and terminating in a coolant discharge edge at the heel of the foot portion, said coolant discharge edge being aimed at a slight angle toward the surface of the casting band, said coolant conduit means having orifice means connected therewith and aimed at a slight angle toward said coolant application surface, said member having a sharp leading edge at the toe of said foot portion with a coolant scoop surface extending along said second side thereof from said leading edge, said coolant scoop surface having a plurality of abrupt discontinuities therein for reducing the frictional drag on the diverted coolant, and said colletcion gutter being arranged to receive the diverted coolant from said scoop surface.

11. Cooling apparatus for use in casting molten metal for providing a rapidly moving layer of liquid coolant travelling along a surface to be cooled comprising a coolant application guide having a planar area extending generally at a large angle toward the surface to be cooled, said guide having a curved area contiguous with said planar area, said curved area terminating in a discharge edge which is near to the surface to be cooled, said discharge edge being directed at a slight angle toward said surface, a coolant conduit, a plurality of nozzles connected with said conduit and being aimed as substantially grazing incidence toward said planar area for directing jets of the coolant at a slight angle onto said planar area for diverging said jets into a substantially uni-formlayer of coolant travelling along said planar area onto said curved area and discharging from said discharge edge onto the surface to be cooled, said coolant application guide having a scoop surface on the opposite side thereof from said curved area for diverting excess coolant from the surface to be cooled, said scoop surface having a plurality of abrupt discontinuities therein for reducing the frictional drag on the diverted coolant, and collection gutter means for receiving the diverted coolant.

12. In a casting machine of the type wherein molten metal is cast into metal strip by confining the molten metal between a pair of moving flexible belts having portions travelling in spaced face-to-face relationship defin- 10 v ing a casting region between said belts, and wherein the belts are supported by rows of fin-like elements engaging the outer surface of each belt, a plurality of coolant application and scoop units for creating and maintaining a rapidly moving layer of coolant travelling along the surface of each belt and passing between said fin-like elements, said units each including a rigid member positioned between adjacent rows of said elements and havinga foot portion closely spaced from the belt with a sharp leading edge on said foot portion, said rigid member having a coolant scoop surface extending along one side thereof directed away from said sharp leading edge, coolant collection means for receiving coolant from said scoop surface, said rigid member having a coolant application guide surface, extending along the opposite side thereof to the foot portion with a discharge edge for the coolant at said foot portion, a coolant conduit extending along said member near said application guidesurface, and a plurality of nozzles connected tosaid conduit at spaced points therealong, said nozzles being aimed at a slight angle toward said application guide surface at a slight angle for producing a layer of coolant travelling along said application guide surface toward the discharge edge at the foot portion of said member.

'13. In a continuous casting machine of the type wherein the molten metal is held by a moving flexible band while the molten metal becomes solidified, means for supporting the moving band and for creating and maintaining a rapidly moving layer of liquid coolant travelling along the surface of the band comprising a plurality of rows of narrow fin-li ke rotatable elements behind the band in rolling engagement with the surface of the band, said rows of elements being closely spaced with a clearance between adjacent rows which is substantially less than the diameter of said rotatable elements, and a plurality of coolant application and scoop units each including coolant conduit means behind the rotatable elements, coolant collection gutter means behind the rotatable elements, and a rigid member extending between adjacent rows of elements with the foot of said member being closely adjacent to the surface of the band, said member having a front face forming a scoop surface and a rear face forming a coolant application surface with a discharge edge at the foot, said gutter means being arranged for receiving coolant from said scoop surface, and said conduit means having nozzle means aimed at a slight angle toward said applicationsurface for providing a layer of coolant travelling along said application surface toward the discharge edge, said layer of coolant shooting off from said discharge edge toward the surface of the band for converging therewith.

14. In a continuous casting machine as claimed in claim 13, a plurality of rows of rotatable elements having a spacing less than 60% of their diameter for providing closely spaced points of support for the flexible band.

15. In a casting machine of the type wherein molten metal is cast into metal strip by confining the molten metal between a pair of moving flexible belts having portions travelling in spaced face-to-face relationship defining a casting region between said belts, and wherein each of the belts is supported by a plurality of parallel rollers having fin-like ridges engaging the outer surface of the belt, a plurality of coolant application and scoop units for creating and maintaining a rapidly moving layer of coolant travelling along the surface of each belt beneath the rollers and passing between said fin-like ridges, said units each including a rigid member extending through the spacing between adjacent rollers toward the belt from a position above the adjacent rollers, said rigid member having a foot portion near to the belt with a sharp leading edge on said foot portion, said rigid member having a coolant scoop surface extending along one side thereof upwardly away from said sharp leading edge, coolant collection means above the adjacent rollers for receiving coolant from said scoop surface, said rigid member havabove said adjacent rollers and near saidapplication guide surface, and a plurality of nozzles connected to said conduit at spaced points therealong, said nozzles being aimed at a slig'ht'angle'tow'ard' said application guide surface for producing a layer of cool-ant travelling downwardly alongsaid application guide surface toward the discharge edge at the foot portion of said member, said spacing between adjacent rollers being less than60% of the diame'ter of said fin-like ridges;

16. Cooling apparatus for use in casting molten metal for providing a rapidly moving layer of, liquid coolant travelling along a surface to be cooled comprising a coolant application guide having a planar area extending said guide having a curved area contiguous with said generally at a large angle towardthe surface to be cooled,

planar area, said curved area terminating in a discharge edge whichis near to the surface to be cooled, said discharge edge being directed at a slight angle toward said surface, a coolant conduit, a plurality of nozzles connected withsaid conduit,- said nozzles being directed at a slight angle toward said planar area for diverging the liquid jets therefrom into a substantially uniform layer of coolant travelling toward said curved area, and a plurality of smoothing guide vanes extending along said curved area toward said discharge edge, said vanes being a parallel with the direction of travel of said coolant toward said discharge edge. a

Rossi Oct. 14, 1952 Hazelett Sept. 22, 1959

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