US3628594A

US3628594A - Apparatus for reducing the cross section of a continuous cast strand

Info

Publication number: US3628594A
Application number: US790608A
Authority: US
Inventors: Kurt Reinfeld; Emmanuel V Gouye
Original assignee: Koppers Co Inc
Current assignee: Raymond Kaiser Engineers Inc
Priority date: 1969-01-13
Filing date: 1969-01-13
Publication date: 1971-12-21
Anticipated expiration: 1988-12-21
Also published as: ES372154A1; CA933329A; GB1258735A; ES395002A1

Abstract

Apparatus for reducing the cross section of a continuous cast strand includes pairs of powered rollers disposed in horizontal planes, and pairs of powered rollers, disposed in vertical planes on opposite sides of the continuous cast strand. The strand passes between the roll pairs which are moved together by fluidactuated cylinder piston mechanisms to reduce the vertical and horizontal cross-sectional dimensions of the cast strand.

Description

United States Patent -[72] Inventors 7 Kurt Reinfeld;

Emmanuel V. Gouye, both of Pittsburgh, Pa. [21] Appl. No. 790,608 [22] Filed Jan. 13, 1969 [45] Patented Dec. 21,1971 [73] Assignee Koppers Company, Inc.

[54] APPARATUS FOR REDUCING THE CROSS SECTION OF A CONTINUOUS CAST STRAND 4 Claims, 8 Drawing Figs.

[52] US. Cl 7 164/270, 72/245, 164/282 [51] Int. Cl 322d 11/12 [50] Field of Search... 164/76, 82, 270, 282, 283; 72/237, 244, 245, 238; 287/5207 [56] References Cited UNITED STATES PATENTS 3,543,555 12/1970 Baumann et a1. 72/245 X 3,554,269 1/1971 Hermann et a1. 164/76 X 538,268 4/1895 McCracken 72/238 2,042,872 6/1936 Talbot 72/238 Primary Examiner-R. Spencer Annear Attorneys-Sherman H. Barber and Olin E. Williams ABSTRACT: Apparatus for reducing the cross section of a continuous cast strand includes pairs of powered rollers disposed in horizontal planes, and pairs of powered rollers, disposed in vertical planes on opposite sides of the continuous cast strand. The strand passes between the roll pairs which are moved together by fluid-actuated cylinder piston mechanisms to reduce the vertical and horizontal cross-sectional dimensions of the cast strand.

ATENTED BEEN an SHEET 2 0F 3 INVENTORS MW .Ef/NFELD PATENTED mm W SHEET 3 OF 3 INVENTORS KMFT EE/NFELD [MAMA/(15L 1/ 505 5 Ear/mg APPARATUS FOR REDUCING TI'IE CROSS SECTION OF A CONTINUOUS CAST STRAND BACKGROUND OF THE INVENTION In the technique for producing rectangular continuous cast strands in machines of the low-head type, the cast strand is formed in a vertical reciprocating mold, is bent toward the horizontal, then is straightened and thereafter passes through a cutoff mechanism which automatically severs the cast strand into billets of desired length. These billets are then allowed to cool and are collected and stacked in an area where they are available for further metal working. The cold billets are later reheated in a furnace and worked upon by reducing rollers until a section of the desired characteristics is produced.

The center core of the billets obtained by this casting process frequently have undesirable center core porosities and segregations. Also, a high rate of production of small billet sections requires either a large number of cast strands or a difficulty controlled high-casting speed per strand at or near the point of complete solidification of the strand center core, before the cast strand is cut into billets.

Those skilled in the art will recognize the economic advantages resulting from in-line" reduction of a continuous cast strand.

The term in-line" reduction as used herein refers to the fact that the cross-sectional dimensions of the cast strand are physically reduced, and the strand is elongated by the apparatus of the invention while the strand is moving steadily in a line from one portion of a continuous casting machine to another portion.

It should be clear that the many usual operational steps, such as billet reheating and high-temperature rolling, are eliminated by passing a continuous cast strand through an inline" reduction apparatus, such as that of the present invention.

How the equipment of the present invention effectively accomplishes in-line reduction of the cross section of a continuous cast strand is set forth in the following description of one embodiment and modifications of the invention, which are exemplified in the accompanying drawings.

SUMMARY OF THE INVENTION Apparatus for reducing the cross-sectional dimensions of a continuous cast strand comprises a pair of units pivotally mounted on opposite sides of the cast strand; each such unit including a hollow shell that is journaled to a shaft about which the shell pivots; a roller is journaled to each shell and the opposed pair of rollers is adapted to contact the sides of the cast strand when the units are moved toward each other in a controlled manner.

BRIEF DESCRIPTION OF THE DRAWING The invention is illustrated in the drawing wherein:

FIG. 1 is a schematic view of a continuous casting machine including one embodiment of invention in accordance with the invention;

FIG. 2 is a schematic perspective view of the embodiment of invention shown in FIG. 1;

FIG. 3 is a sectional view along line III-III of FIG. 2;

FIG. 4 is a sectional view along line IV-IV of FIG. 3;

FIG. 5 is a schematic elevational view of a first modification of the invention;

FIG. 6 is a sectional view along line VI-VI ofFIG. 5;

FIG. 7 is a schematic elevational view of a second modification of the invention; and

FIG. 8 is a schematic modification of a portion of the apparatus of FIG. 1.

DETAILED DESCRIPTION FIG. 1 illustrates a continuous casting machine 10 including in-line continuous cast strand reducing apparatus 11 (FIG. 2) in accordance with the invention. The apparatus 11 includes a first assembly 13, and a second assembly 15 spaced apart from the first assembly 13.

The first assembly 13 includes a pair of first 17 and second 19 housing units that are journally mounted. The second assembly 15 also includes a pair of third 27 and fourth 29 housing units that are journaled as at 21 and 23 respectively to a support frame 25. The support frame 25 may be secured in a known manner to a suitable foundation or to the ground.

Because the first 17 and second 19 housing units are substantially like the third 27 and the fourth 29 housing units, the following description of the first housing unit 17 suffices as a description of the other housing units ll9, 27,.and 29.

First housing unit 17 (FIG. 3) includes a frame or a hollow shell 31 to which are journaled a plurality of shafts and gears. As viewed in FIG. 4, the left-hand end of the shell 31 is journaled to a vertical pivot shaft 33 that is journaled at the bottom to a suitable support 35.

Adjacent the vertical pivot shaft 33, there is a horizontally arranged fluid piston motor 37 that may be similar to the type of piston motor manufactured and marketed by Vickers Division of Sperry Rand Corporation. The fluid piston motor 37 has a power output worm 39 that is suitably journaled as at 41 to the shell 31. The power output worm 39 meshes with a worm gear 43 that is fixed to the lower end portion of a vertical shaft 45.

The vertical shaft 45 is journaled both at the bottom, in a bearing 47 mounted in the shell 31, and at the top, in a bearing 49 mounted in a cover 51 that is removably secured, as by capscrews 53, to the shell 31. The upper portion of the shaft 45 is formed as a spur gear 55 that meshes with a driven gear 57 mounted to another vertical shaft 59 that is substantially parallel to the vertical shaft 45.

Shaft 59 is journaled both at the top in a bearing 61 mounted in the cover 51, and at the bottom in a bearing 63 mounted in the shell 31. The lower end portion of the shaft 59 includes a pinion 65 that meshes with a shaft-mounted idler gear 67 suitably journaled in top and bottom bearings 69 that are mounted in the shell 31, as suggested in FIG. 4.

The idler gear 67 also meshes with a drive gear 71 mounted to a vertical shaft 73 that is substantially parallel to the other

vertical shafts

45 and 59. The vertical shaft 73 is journaled at the bottom in a bearing 75 mounted in the shell 31 and, at the top, in a bearing 77. The shaft 73 also carries a shaped, billetreducing roller 79 that is located in an opening 81 in the shell 31, so that opposed rollers 79, of adjacent

pivotable housing units

17, 19, can coact on a continuous cast strand, such as strand 101 passing between such rollers.

The top bearing 77 is mounted in a bearing block 78 that is removably mounted to the shell 31 in such a way that both the bearing 77 and the bearing block 78 can be quickly and easily removed from the shell 31.

The bearing block 78 is provided with a cover 78a, secured thereto as by lifting eyebolts 78b or in any other suitable manner, and a nut 78c is threaded onto the upper end of the shaft 73 having a reduced cross section at its upper end portion.

The upper end portion of the shaft 73 is provided with internal lubricating oil or grease passage (not shown) and a quickdisconnect hose assembly 78d is attached to the shaft upper end, as shown in FIG. 4.

At the bottom of the bearing block 78, there is spacer ring 78e which engages both the shaft 73 and the bearing block 78 to maintain these units in spaced apart relation.

When it is desired to change the roller 79, only the hose assembly 78d, the nut 780 have to be removed and then the bearing 77 and bearing block 78 may be removed. After the spacer ring 78e is removed, the roller 79 may then be easily and quickly removed. A new roller may thereafter be installed and the other units reinstalled.

The frame or shell 31 is provided with both upper 83 and lower 85 outwardly projecting clevises, each of which is adapted to cooperate with a tongue portion 87 of a piston rod 89 that extends out of a cylinder-piston assembly 91. The

cylinder-piston 91 also has a tongue portion 93 that cooperates with each of both upper 95 and lower 97 clevises of the cooperative second housing 19.

The first assembly 13 is spaced a short distance apart from the second assembly 15, as shown in FIG. 2, and between the two

assemblies

13, 15, there is a transition or guide piece 99 surrounding a continuous cast strand 101 passing through the apparatus 11. At the end of the transition or guide piece 99 nearest the first assembly 13 (FIG. 2) there is a horizontal guide roller 103 that is journaled in bearings 105 mounted to the support 35, as suggested in FIG. 3. The guide roller 103 supports the cast strand 101 in passing from the second assembly 15 through the transition or guide piece 99 into the first assembly.

In operation of the continuous casting machine 10, a continuous cast strand 101, after being bent and straightened in apparatus 129 so that it moves in a substantially horizontal plane, enters the apparatus 11 through a guide 107. The cast strand 101 then passes between two horizontal rollers 79 that are mounted to shafts 109 and 111 of the second unit 15. The horizontal rollers 79 move toward each other when the pair of fluid-actuated cylinder pistons 113 are activated, whereby the continuous cast strand 101 is reduced in thickness. The horizontal rollers 79 are driven by power supplied to the piston motors 115, 1 17, that are like the piston motor 37.

In the first assembly 13, the continuous cast strand 101 passes between the vertical rollers 79 that are likewise movable toward each other so that the cast strand is now reduced in width. The rollers 79 are driven by the powered piston motors 37 acting through the gear trains, described herein, located inside the

housing

17 and 19.

As shown in FIG. 2, the third housing 27 is provided with a fixed stop 119 and the fourth housing 29 is provided with an upright arm 120 which coacts with the fixed stop 119 to prevent the horizontal rollers 79 from touching each other when the cylinder-piston assemblies 113 are not under pressure. The first 17 and second 19 housings, being pivotable about vertical axes, do not require the same positive stop 119 and cooperative arm 120 which are associated with the third 27 and fourth 29 housings.

In the continuous casting machine 10, molten metal 121 flows from a tundish 122 into a vertically reciprocable mold 123 wherein the cast strand 101 is continuously formed. The continuous cast strand 101 is withdrawn from the mold 123 by powered pinch rollers 124, and the strand passes through a spray chamber 125 wherein cooling water is directed onto the surface of the strand 101. From the pinch rollers 124, the cast strand 101 is urged in the usual manner by rollers (not shown) toward the horizontal, and is supported by rollers 127 of an arcuate apron structure. The arcuate strand 101 passes into a straightener device 129 wherefrom it emerges in a horizontal plane.

Upon emerging from the straightener apparatus 129, the cast strand 101 enters the in-line" reduction apparatus 11 described hereinbefore and both the vertical and the horizontal dimensions of its cross section are reduced.

FIG. illustrates a modification of the apparatus 11 described herein and includes another form of straightener apparatus 131 disposed between an initial in-line reduction assembly 133 and a secondary in-line reduction assembly 135.

Basically the initial in-line reduction assembly 133 includes the same pivoted

housing units

137, 139, each supporting a horizontal reduction roller 141; the

housing units

137, 139 being pivoted at pins 143 to a support frame 145 bolted to a base 146.

The secondary in-line reduction assembly 135 is substantially identical with the first in-line reduction assembly 13 described previously herein except that the support 145 is adapted to pivotally support opposed pairs of arms 147, 149. The support frame 145 also supports a horizontal roller 151 which functions in the manner of roller 103 mentioned previously. The secondary in-line reduction assembly likewise includes a pair of opposed vertical reduction rollers 153 that are similar to the rollers 79.

The pairs of pivoted arms 147, 149 are journaled to a common shaft 155 and first cylinder-piston assemblies 157 interconnect arms 147 to arms 149, while second cylinder-piston assemblies 159 interconnect arms 149 and a support 161 to which the assembly 135 is bolted. Pairs of arms 147, 149 are disposed on opposite sides of the apparatus 131.

Each arm 147, 149 of the opposed pairs of arms are interconnected by a structural member, such an an l-beam 163, to provide rigidity to the arms 147, 149. Between each pair of opposed arms 147 and 149, there is journaled a roller 165. The pair of rollers 165 are arranged to be on a single arc having a center in the pivot shaft 155.

The vertical 153 as well as the horizontal rollers 141 are adapted to be easily and quickly removed, in that each roller is mounted to a shaft 167 (FIG. 6) having a reduced diameter upper end above the roller 153. A bearing 169 coacts with the shaft 167 and with a bearing housing 171 that is removably mounted in each one of the pivoted units comprising the assembly 135. As described previously herein, a spacer ring 173, cooperating with the shaft 167 and the bearing 169 to maintain the shaft centered in the bearing housing 171.

The upper end portion of the shaft 167, above the top of the bearing 169 is threaded as at 174 and coacts with a nut 175 having a projecting arm 177. The nut 175 is provided with seal ring 179 that coacts with a cover 181 that is secured in a known manner to the top of the bearing housing 171 to seal the bearing housing 171. The nut 175 also engages the bearing 169 to hold the bearing and its housing 171 in cooperative relation.

In operating a continuous casting machine like that of FIG. 1, but including the modified apparatus of FIG. 5, the cast strand 101 enters the unit 137 which has been arranged so that the rolls 141 are spaced apart wide enough to freely pass the head end of the curved strand. The head end of the strand also passes between the rollers 165 which are elevated by the cylinder-piston assembly 159.

Then, by actuating the cylinder-piston assembly 159 to move the rollers 165 and arms 147, 149 downward, the head end of the cast strand 101 is disconnected from a usual starter bar 102, Then, in conjunction with the fixed horizontal roller 151 acting as an abutment, the strand is bent downward and extends substantially horizontal.

Thereupon, the rolls 141 may be brought together by actuating the cylinder-piston assemblies 113 to reduce the thickness of the cast strand 101. The width of the cast strand may be controlled by varying the apart spacing of the vertical rollers 153 as described hereinbefore.

The unit 137 also may serve as a withdrawal set of rollers and, when operated as such, the withdrawal or pinch rollers 124 are not required. As soon as the rollers 141 have been brought into engagement with the cast strand 101, the both reduce the vertical dimension of the cross section of the strand and withdraw and strand from the mold of the casting machine.

FIG. 7 illustrates another modification of the way in which the reducing rollers may be mounted in a frame or housing, such as housing 183. Housing 183 is similar to the

housings

17, 19, 27, 29, except that a reduction roller 185 is mounted to the upper end of a shaft 189 and not intermediate the ends of the shaft 73, as shown and described previously. The housing 183, however, supports the same gearing and shafting as the frame or shell 31 illustrated in FIGS. 3, 4 and described herein.

The reduction roller 185 is cantilever mounted at one end of a reduced diameter shaft portion 189, and rests against a shoulder 191 of the shaft 187. A pair of rotatable roller-retaining lugs 193 are secured to the shaft 187 by capscrews 195, and when the retaining lugs 193 are not engaging the roller 185, as shown in FIG. 7, the roller 185 may be easily and quickly removed from the shaft end 189. So, too, a new roller may be easily and quickly installed on the shaft end 191, and then the retaining lugs 193 can be rotated so as to engage the roller, as shown in FIG. 7, and the capscrews 195 may be tightened to secure the roller 185 in place on the shaft end 191.

FIG. 8 illustrates a modification of the apparatus of FIG. 1 that includes a powerassisted roller 197 mounted to a cylinder-piston arrangement 199. The roller 197 is located between the units 13, and is adapted to move vertically.

In the arrangement of apparatus 11a shown in FIG. 8, the unit 15 serves as a reducing and withdrawing set of rollers that take the place of the pinch rollers 124. When the unit 15 is operated in this manner the head end of the cast strand 101 initially passes freely through the rollers under the influence of a conventional starting bar like starter bar 102 of FIG. 5. As soon as the head end clears the unit 15, the roller 197 is moved downward by the cylinder piston 199, the strand coacts with roller 103 and the cast strand is disconnected from a starter bar such as bar 102. The cast strand is supported by the roller 103 and is directed horizontally into the reducing unit 13.

Those skilled in the art will recognize many significant features and advantages in the present invention, among which are that:

The in-line reducing apparatus of the invention is simple in operation and is adaptable to reduce the cross-sectional dimensions of a continuous cast strand in only one direction or in two directions as preferred;

Continuously cast strands having a relatively large cross section are quickly and effectively reduced in section dimensions thereby significantly increasing the throughput capacity of a continuous casting machine; and

The in-line reduction equipment of the invention achieves an increase in output production per cast strand of a given cross section, and a considerable improvement in product quality and as a result of rewelding the porous central region of the strand by compression; and

The carbon segregation and other segregations in the center core of the cast strand are significantly reduced after passing through the in-line reduction equipment of the present invention.

What is claimed is:

1. In a continuous casting machine wherein a cast strand is withdrawn from a mold by a started bar releasably connected to the strand, the improvement comprising:

a. a first pair of units spaced apart from a second pair of units with the units of each pair being disposed on opposite sides of said cast strand, each such unit comprising: i. a support,

ii. a first shaft journaled in said support,

iii. a frame journaled to said shaft,

iv. a roller mounted to a second shaft carried by said frame,

v. means for rotating said second shaft and said roller, and

vi. means connecting together the units of each pair of units to urge said pair of units toward each other and said rollers into surface engagement with said cast strand to reduce one cross sectional dimension thereof; and

b. means disposed between said first and said second pairs of units engageable with said strand to disconnect said strand from said starter bar and to direct said cast strand toward said second pair of units including: i. a pair of arms pivoted about a common axis, ii. a roller supported by each arm, iii. an abutment fixed in relation to said axis, and iv. means to move said pair of arms about said common axis for causing said rollers to engage said strand and urge it into engagement with said fixed abutment so the strand is bent downward to extend substantially horizontal. The invention of claim 1 including: a. means for pivoting one of said arms relative to the other arm. 3. in the apparatus of claim 1, the improvement comprising: a. means for quickly releasing and disconnecting said roller to said second shaft. 4. The invention of claim 1 wherein: a. said roller is cantilever mounted to said shaft, and includin b. m eans to quickly detach and secure said roller to said shaft.

Claims

1. In a continuous casting machine wherein a cast strand is withdrawn from a mold by a started bar releasably connected to the strand, the improvement comprising: a. a first pair of units spaced apart from a second pair of units with the units of each pair being disposed on opposite sides of said cast strand, each such unit comprising: i. a support, ii. a first shaft journaled in said support, iii. a frame journaled to said shaft, iv. a roller mounted to a second shaft carried by said frame, v. means for rotating said second shaft and said roller, and vi. means connecting together the units of each pair of units to urge said pair of units toward each other and said rollers into surface engagement with said cast strand to reduce one cross sectional dimension thereof; and b. means disposed between said first and said second pairs of units engageable with said strand to disconnect said strand from said starter bar and to direct said cast strand toward said second pair of units including: i. a pair of arms pivoted about a common axis, ii. a roller supported by each arm, iii. an abutment fixed in relation to said axis, and iv. means to move said pair of arms about said common axis for causing said rollers to engage said strand and urge it into engagement with said fixed abutment so the strand is bent downward to extend substantially horizontal.

2. The invention of claim 1 including: a. means for pivoting one of said arms relative to the other arm.

3. In the apparatus of claim 1, the improvement comprising: a. means for quickly releasing and disconnecting said roller to said second shaft.

4. The invention of claim 1 wherein: a. said roller is cantilever mounted to said shaft, and including b. means to quickly detach and secure said roller to said shaft.