US3024528A

US3024528A - Method of premoving surface defects in ingots

Info

Publication number: US3024528A
Application number: US839468A
Authority: US
Inventors: Kielar Andrew Anthony
Original assignee: International Harverster Corp
Current assignee: Navistar Inc
Priority date: 1959-09-11
Filing date: 1959-09-11
Publication date: 1962-03-13
Anticipated expiration: 1979-03-13

Description

March 13, 1962 A. A. KIELAR METHOD OF REMOVING SURFACE DEFECTS IN INGOTS Filed Sept. 11, 1959 55 INVENTOR 76z'eiar fivarew (LL/.2, C)

A TmR/VEY United States Patent 3,024,528 Patented Mar. 13, 1962 fifice 3,924,528 METHOD OF REMOVING SURFACE DEFECTS 1N INGOTS Andrew Anthony Kielar, Chicago, Ill., assignor to Intel-national Harvester Company, Chicago, 111., a corporation of New Jersey Filed Sept. 11, 1959, Ser. No. 839,468 8 Qlaims. (Cl. 29-526.4)

This invention concerns an improved method for removing surface imperfections in ferrous metal ingots after casting.

In the casting of iron or steel ingots the molten metal is poured into an ingot mold. The ingot mold is generally of tubular construction and of substantially square configuration in cross section. After the ingot has cooled sutlicicntly within the mold it is extricated therefrom by forcing it endwise or longitudinally with respect to the mold until it is discharged. Certain of the ingot molds comprise inner tapered walls which facilitate the removal of the ingot from the mold. While the ingot is cooling within the mold there is generally a tendency for the ingot to become substantially welded to certain portions of the interior of the mold. When this occurs, the surface of the ingot becomes rough and contains sur' face imperfections and particularly after the ingot has been removed from the mold. Also, in many instances the surface of the ingot is sometimes embedded with particles of slag which also create projections or surface imperfections and defects. After the ingot has generally been removed from the mold, these imperfections and defects are removed by reheating the surface and grinding or chiseling away the imperfections. This is generally a costly procedure and is very unsatisfactory. Such imperfections, when left in the surface of the ingot, continued to be in existence even after rolling of the ingot so that the resultant product (covers, bars, strips, sheets, plates, shapes, billets, slabs) has surface defects which are rejected by the ultimate consumer. In many in stances the ingot contains such imperfections in its surface that the entire ingot has to be scrapped. It is therefore a prime object of this invention to provide an improved method for removing surface imperfections in ingots immediately after the ingots have been cast in an ingot mold.

A still further object is the provision of an improved process for removing surface imperfections in ingots while simultaneously removing the ingot from the mold into which it has been poured.

A still further object is the provision of an improved inexpensive, efficient, and effective method of removing surface imperfections from an ingot while the ingot is still substantially warm as a result of the casting operation.

A still further object is the provision of an improved method of treating the surface imperfections of a cast ingot with the utilization of a mold and certain portions thereof which are effective in the accomplishment of the method.

A further object of the invention is to provide an improved method of removing an ingot from an ingot mold while simultaneously smoothing the surface of the ingot to remove surface imperfections by displacement of metal.

Still another object of the invention is to provide an improved method of removing surface imperfections from an ingot while the said ingot is still heated from a casting operation, the said method comprising the steps of removing surface portions of the metal thereby simultaneously deleting any surface imperfections which might exist.

These and other objects will become more readily apparent from a reading of the specification when examined in connection with the accompanying sheet of drawing.

In the drawing:

FIG. 1 is a side elevational view, with portions thereof in section, of an ingot mold of a type conventionally used in the steel industry;

FIG. 2 is a perspective view of a typical and conventional ingot after it has been removed from an ingot mold;

FIG. 3 is a cross sectional view through a device showing the method by which an ingot may be removed from an ingot mold and whereby the surface imperfections are removed from the surfaces of the ingot; and

FIG. 4 is a cross sectional view through a modified apparatus showing a modified ingot mold including means for removing surface material from the ingot simultaneously while the same is removed from the ingot mold.

Referring now particularly to FIG. 2, an ingot is generally designated by the reference character 10. The ingot 10 comprises a substantially square elongated body 11 having at one end four tapered side surfaces 12 terminating in a first end 13. The ingot is also provided with an opposite end 14. The body 11 also comprises a plurality of flat or substantially parallel side surfaces 15 adjacent the end 14.

An ingot mold is generally designated at 16. The ingot mold 16 is of tubular construction, substantially square in design, and includes a bottom plate 17 upon which the ingot sets during a casting operation. The ingot mold 16 comprises four side walls 18 and handling hooks 19 are disposed on opposite sides of said side walls 18. A plurality of inner tapering Walls 20 are provided within the ingot mold 16. The ingot mold further includes parallel or straight walls 2-1 defining with the walls 20 a chamber generally designated at 22. The chamber 22, as best shown in FIG. 3, is provided with opposed open ends 23 and 24.

Referring now to FIG. 3, a support 25 is shown suitably supported on the ground. The support 25 comprises a table 26 having a recessed portion 27 provided at one end of a stop 28. The ingot mold 16 is shown positioned within the recess 27 with one end of the mold 16 in engagement with the stop 28. The support 25 is associated with a fluid extensible device designated at 29. The fluid extensible device 29 comprises a bracket 30 suitably connected, by means of bolts 31, to the support 25. The extensible device 29 comprises a cylinder 32 having a suitable hollow chamber 33 to which fluid under pressure is introduced by means of a conduit 34 leading to a source of pressure (not shown). A piston 35 is adapted to reciprocate within the chamber 33 and to move in a longitudinal direction toward the ingot 16 when fluid under pressure is supplied to the chamber 33. The

piston 35 is provided at one end with a suitable ram member 36.

In the formation of ingots, the ingot mold 16 is suitably supported in an upright position on top of the plate 17. The metal is then poured from a suitable ladle (not shown) and the ingot mold chamber 22 is suitably filled. The ingot mold is then supported by means of the hooks 19 from a suitable crane and is transferred to the support 25 whereupon it is laid horizontally in the manner shown in FIG. 3 with one end suitably supported against endwise movement by means of the shoulder 28. The piston 35 is now moved in the direction of the arrow, in FIG. 3, whereupon the end 13 of the ingot is engaged by the ram 36 and the ingot 16 is moved longitudinally or lengthwise of the mold 16. It is apparent that the cross sectional diameter or dimension between the straight walls 21 is of lesser dimension than a cross sectional dimension taken at any point along the tapering walls 20.

Thus the parallel or straight walls 21 form a restricted opening within the chamber 22 and upon the longitudinal or endwise movement of the ingot, during its discharge from the ingot mold, these walls will cause the surfaces, in the area of the tapered walls 20, to become displaced or a change in form is effected. Thus the tapering walls 20, or that portion between the said tapering walls, is extruded through the restricted portion defined by the walls 21. The ingot shown in FIG. 2, therefore changes to a substantially square or rectangular shape and simultaneously the imperfections which are in the surfaces 12 are removed by the displacement of metal which may be similar to forging or extruding. The discharging and surface treating method are accomplished while the ingot 11 is still substantially heated from the casting operation. Thus the ingot, which may have surface imperfections, comprising projections or depressions or slag elements, are in effect removed during the discharging operation since the shape of the ingot 11 changes and the surfaces are worked upon.

Thus it is clear that the ingot is changed in shape while it is simultaneously discharged from the ingot mold. The change in shape causes the removal of surface imperfections thus substantially reduces or entirely eliminates any rework, scarfing, or other process to remove these imperfections. The piston and ram 36 may be suitably returned to their original position, either by spring elements or by other suitable means.

Thus the normal interior wall structure found in conventional ingot molds is effective during the present improved process, for restricting the movement of the ingot during discharge while simultaneously working upon the outer surface of the ingot to effectuate the removal of surface defects.

In FIG. 4 the ingot is designated at 40, and in this case the ingot 40 comprises four parallel sides 41 which may be of square configuration. An ingot mold is designated at 42, the said ingot mold having inner walls 43 defining a chamber 44 open at opposite ends as indicated at 45 and 46. One end of the ingot 40 is provided with outer flanges 47. A supporting structure is designated at 48 and comprises a substantially flat table 49 suitably supported on the ground. The table 49 is provided with a recess 50 having at one end a shoulder 51. A second table 52 is positioned adjacent one end of the ingot mold 42 for receiving the ingot 40 as it is discharged.

A fluid extensible device 53 comprises a cylinder 54 which is suitably connected, by means of a bracket 55, to the table 52. The cylinder 54 comprises a chamber 56 within which a piston 57 is mounted for reciprocation.

A conduit 58, similar to the conduit 34 in FIG. 3, is provided to deliver fluid under high pressures to the chamber 56. A ram 59 is connected to the piston 57 at one end thereof. The supporting structure 48 also includes a flange 60 projecting longitudinally for engaging the ingot mold 42 to retain the same in horizontal displacement.

A die element 61 is provided with a restricted opening 62 having at one end a foursided square shaped cutting edge 63. The shape of the cutting edge 63 conforms to the shape of the chamber 44. Spacers 64 disposed between the die 61 and flanges 47 suitably space the die 61 which is rigidly held on the flanges 47 by means of bolts and nuts 65.

In the method accomplished by the utilization of the apparatus shown in FIG. 4 the cylinder 57 is moved in the direction of the arrow whereupon the ram 59 engages the ingot 40 to move the same endwise or longitudinally from the chamber 44. During this movement, the ingot 40, which is still in a heated condition just after casting, has its outer surfaces or parallel sides 41 engaged by the cutting edges 63. The opening 62 is of smaller cross sectional dimension than the cross sectional dimension of the ingot 40 so that a thin edge 66 is peeled from the surfaces or sides 41. The movement of the piston 57 continues until the ingot 40 is completely discharged from the ingot mold 42 and rests upon the table 52. Any surface imperfections on the ingot 40 are thereby removed by peeling of the portions 66. The finished ingot, therefore, has a smooth clean surface as it is discharged from the die. Thus the ingot is simultaneously removed from the ingot mold while the surface imperfections are also removed and while the ingot is still in a plastic condition.

Thus it can be seen that the objects of the invention have been fully achieved and that an improved method for removing surface imperfections in ingots and a modification thereof have been described. It must be realized that changes in the method or in the apparatus which may perform the method, may be made without departing from the spirit of the invention as disclosed or from the scope thereof as defined in the appended claims.

What is claimed is:

1. A method of removing surface imperfections in a metal ingot after pouring of the metal into an ingot mold, the ingot mold having inner tapering walls and parallel walls forming a chamber open at opposite ends, said tapering walls converging toward the parallel walls whereby said portion of the chamber adjacent said parallel walls is narrower in cross section than other portions of said chamber, said ingot mold having outer tapering and parallel walls conforming to said walls of said chamber, consisting of supporting said ingot mold against lengthwise movement with said ingot in a heated condition, applying a force against one end of said ingot adjacent one open end of said chamber to move said ingot lengthwise relative to said chamber toward and through said narrow portion and the other open end of said chamber, whereby said tapered walls of said ingot are formed substantially parallel and surface indentations and projections are removed by the displacement of the metal.

2. A method of treating a metal ingot, having a certain cross sectional dimension, after it is formed in an ingot mold, said mold having opposed open ends; consisting of supporting said mold against longitudinal move ment, applying a force through one of said open ends against said ingot while said ingot is in a heated condi tion thereby moving said ingot longitudinally relative to said mold, and providing means associated with said mold having a restricted opening of lesser cross sectional dimension than said ingot through which ingot is moved and discharged from the mold, whereby surface imperfections in said ingot surface are removed by the displacement of metal.

3. A method of treating a metal ingot, having a certain cross sectional dimension, after it is formed in an ingot mold, said mold having opposed open ends; consisting of supporting said mold against longitudinal movement, applying a force through one of said open ends against said ingot thereby moving said ingot longitudinally relative to said mold, and providing means associated with said mold having a restricted opening of lesser cross sectional dimension than said ingot through which ingot is moved and discharged from the mold, whereby surface imperfections in said ingot surface are removed by the displacement of metal.

4. A method of treating a metal ingot having a certain cross sectional dimension after it is formed in an ingot mold, said ingot mold having opposed open ends; consisting of supporting said mold against longitudinal movement, applying a pressure longitudinally against said ingot while in a heated condition to move said ingot longitudinally within said mold, providing means associated with said mold, said means having an opening with a cross sectional dimension less than the cross sectional dimension of said ingot, said opening being in registry with one of the open ends of said mold, and continuing said pressure whereby said ingot is moved longitudinally through said opening and is discharged from said mold whereby metal is displaced by said means from the surface of said ingot and surface imperfections in said ingot are removed.

5. A method of treating a metal ingot having a certain cross sectional dimension after it is formed in an ingot mold, said ingot mold having opposed open ends; consisting of supporting said mold against longitudinal movement, applying a pressure longitudinally against said ingot to move said ingot longitudinally within said mold, providing means associated with said mold, said means having an opening with a cross sectional dimension less than the cross sectional dimension of said ingot, said opening being in registry with one of the open ends of said mold, and continuing said pressure whereby said ingot is moved longitudinally through said opening and is discharged from said mold whereby a layer of metal is sheared by said means from the surface of said ingot and surface imperfections in said ingot are removed.

6. A method of improving the outer surface of an ingot after casting in an ingot mold having an open end; consisting of moving the ingot longitudinally from the mold through the open end While the mold is in a heated condition and simultaneously displacing material from the outer surface of the ingot to provide a surface substantially free of imperfections.

7. A method of removing surface imperfections in a metal ingot after pouring of the metal into an ingot mold, the ingot mold having inner tapering walls and parallel walls forming a chamber open at opposite ends, said tapering walls converging toward the parallel walls whereby said portion of the chamber adjacent said parallel walls is narrower in cross section than other portions of said chamber, said ingot mold having outer tapering and parallel walls conforming to said walls of said chamber, consisting of supporting said ingot mold against lengthwise movement, applying a force against one end of said ingot adjacent one open end of said chamber to move said ingot lengthwise relative to said chamber toward and through said narrow portion and the other open end of said chamber, whereby surface indentations and projections are removed by the displacement of the metal.

8. A method of removing surface imperfections in a metal ingot in an ingot mold, said ingot mold having a tubular chamber with opposed open ends, said tubular chamber including an inner wall, and said ingot having an outer peripheral wall conforming to the wall of said chamber, said inner wall including between the open ends of the chamber a restriction having a smaller cross sectional dimension than said ingot, applying a force on one end of said ingot to move the same longitudinally within the chamber while in a heated condition, through the restriction and outwardly from one of said open ends whereby said restriction engages the outer peripheral wall of said ingot and displaces metal therefrom to remove surface imperfections.

References Cited in the file of this patent UNITED STATES PATENTS 418,999 Wellman Ian. 7, 1890 1,101,546 Hixon June 30, 1914 1,672,999 Eyermann June 12, 1928 2,499,292 Black Feb. 28, 1950 2,878,537 Brennan Mar. 24, 1959