JPH06504232A - Two-way insertion thin high cooling large mold - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Two-way insertion thin high cooling large mold Technical field The present invention is applicable to the raw materials used for producing large ingots in the aluminum industry, for example. Concerning the design of this tile mold/larger mold. More specifically, the invention provides Due to the unique shape of the large, low-height mold, when producing large ingots, we It is possible to cool and solidify metal with high cooling efficiency, eliminating cavities and cracks inside the ingot. using a forklift from any of the four sides. It has been shaped so that it can be handled easily. The ingot cannot be processed by any other mechanical or electrical It can also be handled by pneumatic or electronic lifting machines.

Background technology Generally speaking, large ingots sold in today's aluminum industry have two type is the mainstream. The first one is a "traditional" large ingot, the second one is an American ingot. It is a ``thin'' type that is gaining wide acceptance in the luminium industry.

Prior art Figures IA and IB show that the tip of the pyramid is approximately 1200 pounds heavy. This figure shows a typical large traditional ingot lO, which looks like a cut-out inverted version.

The ingot IO has a square planar shape (Fig. IB) and a depth D that is approximately 1/2 of the maximum width W. The mold cavity 23 is defined by a bottom wall 21 and four inclined side walls 21a to 21. It is formed by pouring molten ingot metal into a mold 20 provided with d. This way The shape of the ingot generally depends on a number of factors related to the way the ingot solidifies in the mold. cause problems. In particular, the shape of the mold 20 (FIGS. 1C and ID) allows the ingot to be The final solidification within the central region 12 causes two problems. First, metal The upper surface 14 of the ingot 10 descends due to solidification and capping. The side part 15 should be solidified first. As a result, the outer upper edge 16 is fixed at a relatively high position 17. Therefore, the upper surface 14 The center portion 18 is drawn down through the solidification process and is preferably centered on the top surface. Forms a deep depression.

The second obstacle is that once the top surface solidifies, the molten metal is trapped inside the internal region of the ingot. It is something that can be learned. The solubility of hydrogen gas in molten metal depends on the temperature. It is 0.20 to 0.50 u cm per 100 grams of metal. solidified The hydrogen solubility of the aluminum outer portion is approximately zero. Therefore, the internal melting area Hydrogen is released from the solidifying metal when it is isolated from the external environment by the solidified material. When the liquid is expelled, it tends to form a cavity 19. Illustrated in Figures IA and IB A large 1200 lb. ingot of the type shown below measures 12X at 2 inches thick. 12 inches wide sky? ! It became clear that it was 419. Confinement inside cavity 19 If the hydrogen gas pressure is high enough, the solidified metal above will be destroyed. This failure may result in cracks extending from the cavity to the top surface 14 of the ingot. Special when the ingot is stacked outdoors before being brought to the furnace for remelting. Water from rain or other sources may be trapped inside large ingots. Therefore, when dent +8, crack (not shown), and cavity 19 are combined, , which poses a major safety problem. To avoid placing large ingots with moisture in the furnace. In general, ingots are dried by being stored indoors, which is an unnecessary hassle. It takes.

Large ingots are generally stacked in a storage or storage area before being sent to the furnace. and usually a pair of square bottoms 24 (shaped to engage the recessed edges 22) of the ingot. It is handled by a forklift truck 25 with a fork trunk. Four ingots These recessed edges 22 formed along the bottom edges of the fork The handle can be engaged from either side of the stack and can be used for handling and stacking purposes. It's getting easier. However, the recess 18 on the top surface prevents stacking of large ingots. This is the cause of stability. In other words, the bottom surface 24 of the aligned upper ingot in proper contact with the upper solder surface 14 of the lower adjacent ingot in the stack. If not, it is difficult to balance each ingot in relation to others. There is a tendency to

Newer, thinner, larger ingots are trapped over a wider area through the solidification process. Designed to avoid forming internal melt zones. These large ingots are generally It weighs between 1,500 and 2,000 pounds. The height of these molds is the traditional height of Figure 1. Much lower than large molds. Therefore, for the mold in Figure IA, in a mold with a low height. By using a thinner mold with a long rectangular base to cast the same amount of metal, The bottom area of the ingot is expanded. Thin molds also have end “wings” or Contains an upward extension at the bottom, which facilitates heat release and reduces the volume of large ingots. Even if the depth is increased, the depth will not increase. A thin large ingot is shown in Figure IA. Compared to conventional large ingots, the chance of water intrusion is reduced, and the flat upper side It is a safer product because the surfaces allow better stacking. But long Although not wider than that of the ingot in Figure IA, it still has internal cavities and a slight There are some dents on the top surface.

Other major obstacles to thin molds that have been known for some time relate to handling difficulties. Ru. In particular, the S-crit track is used to hold such ingots between two short sides. It can only be lifted from one side, so when storing or arranging for transportation, Or, when moving to re-dissolve, access will be restricted.

Therefore, one object of the present invention is to have high cooling efficiency and to provide heat transfer at the bottom. By increasing efficiency, the solidification surface inside the large ingot has been improved to move from the bottom to the top. The object of the present invention is to provide a thin mold shape with excellent solidification characteristics.

Another object of the invention is to prevent or reduce the possibility of initial solidification of the top surface of the ingot and Improved thin large ingots that can reduce internal cavities and top surface depressions. and the shape of the mold.

Another object of the invention is to provide a unique feature to the bottom of the ingot by means of depressions or recesses in the bottom of the mold. Form an array of depressions and recesses, and place a pair of forklift teeth on either side of the ingot. Unique large ingot and mold shape that can be inserted even from the ground and overlap perfectly The purpose is to provide the following information.

Disclosure of invention In the present invention, a mold for casting an ingot from molten metal receives molten metal. The mold box has a bottom wall defining a mold cavity to be molded and a side wall extending upward. ing. The bottom wall projects into the cavity and extends longitudinally along the length of the bottom wall. and a first raised region. The first raised area is located at the bottom of the ingot in its cross section. The holes are formed in the longitudinal direction. The bottom wall protrudes into the cavity. at least one second raised area extending widthwise along the width of the ingot; A depression is formed in the cross section in the width direction.

The first and second raised regions are the solidified surface of the molten metal relative to the bottom surface of the ingot or the volume of the ingot. The voids in the ingot are formed so that they move from the bottom to the top of the ingot. Virtually eliminates cavities and depressions on the top surface that inhibit proper ingot stacking. It is prevented.

In a preferred embodiment of the invention, the raised area of 1lEI is located at the center or at the raised ridge. or a protrusion extending along the longitudinal central axis of the bottom wall of the mold cavity. .

The second raised region is suitably shaped like a pair of raised ridges or protrusions, and extends along the width of the bottom wall of the mold. The direction extends on both sides of the central axis and is substantially perpendicular to the central longitudinal projection. The second protrusion is A second depression in the ingot is determined that is continuous with opposing longitudinal sidewalls of the ingot.

The second recesses are spaced apart from each other, and these recesses form the longitudinal sides of the ingot. It receives the teeth of a pair of forklifts approaching from either direction perpendicular to the It is designed to be easy to read and handle.

Another preferred feature of the invention is that the mold extends adjacent the opposing longitudinal sidewalls. The longitudinal edge of the bottom wall of the ingot has a pair of third ridges forming a third (indentation) in the bottom of the ingot. It is said to be the origin area. A third depression is formed at the bottom of the ingot on both sides of the longitudinal center axis. Form side shelves separated by a sufficient distance from each other and perpendicular to the widthwise sides of the ingot. The third (accepts the teeth of a pair of forklifts entering the recess from either direction) It has become so. Longitudinal lateral shelves and width at the bottom of the ingot The arrangement of the second recesses extending in the direction is orthogonal to each other, and The ingot or its stack can be easily handled by a forklift regardless of the are doing. The special feature of these is that they can be inserted from two or more directions due to their indentations. It is designed to be easily accessible during transport for storage or transportation. ing.

Preferred features of the invention include a longitudinally extending central ridge in the mold; By forming a pair of bottom edge ridges (i.e., a third ridge area) extending in the Recessed inward from the bottom of the ingot and at least 25% of its height or the height of the ingot. forming a longitudinal central recess and side ledges. Preferably , the central longitudinal ridge extends over at least 50% of the length of the ingot. Then, the solidification surface progresses from the bottom to the top. The raised lateral shelves are preferably The width of the ingot should be at least 4306 mm to promote the solidification characteristics described above.

The length to width ratio of the ingot is preferably about 1. 6 to 1. 0, The preferred height to length is about 0.2 to 1 or less. Setting various raised areas in combination with the height, length, and width as described above in the preferred embodiment. The solidified surface of thin ingots generally moves from the bottom to the top, Minimizes the occurrence of internal cavities and reduces top surface depressions, while also reducing molten metal This increases cooling efficiency and accelerates solidification, thereby increasing the amount of product produced.

Other objects, features and advantages of the present invention will be apparent from the following description with reference to the accompanying drawings. This becomes clear from reading the detailed description and claims.

Brief description of the drawing FIG. IA is a cross-sectional view of a conventional large ingot taken along line IA-IA in FIG. IB.

FIG. IB is a top plan view of the conventional large ingot of FIG. IA.

Figure IC is the top of the conventional large mold used for casting the large ingots of Figures IA and IB. FIG.

Figure ID is a sectional view taken along the ID-ID line of Figure IC.

FIG. 2 is a top plan view of a thin mold in a preferred embodiment of the invention.

FIG. 3 is a cross-sectional view taken along line 3-3 in FIG.

FIG. 4 is a cross-sectional view taken along line 4-4 extending through the central longitudinal axis of the mold of FIG. It is.

FIG. 5 is a cross-sectional view taken along line 5-5 extending through the center axis in the width direction of the mold in FIG. be.

FIG. 6 is a cross-sectional view taken along line 6-6 in FIG.

Figures 4 and 8 are perspective views of inverted large ingots formed with the molds of Figures 2 to 6. It is.

Best implementation line of the invention 2-6 are engineering scale drawings of a mold 30 according to a preferred embodiment of the invention. It is. Figures 7 and 8 show an ingot formed in the mold 30 schematically shown in Figures 2-6. 40 is shown. Ingot 40 has been inverted to illustrate its bottom surface 52 .

As unique features are described below, the mold 30 has a bottom wall 32 and a side wall 3. 4 and 36, which are new rectangular shaped aluminum plates as illustrated in FIGS. 7 and 8. The shape is such that a minium ingot 40 can be cast. As seen in these Luminium ingot 40 can be easily handled with a forklift regardless of the stacking direction. It is shaped like this. Furthermore, the unique shape of the mold 30 allows for high cooling efficiency. It is possible to solidify the molten metal, and to solidify the ingot 40 from the bottom to the top by the solidification surface j. internal cavities, cracks in the top casting and (unfavorable balance when stacking) This suppresses the occurrence of dents (which caused defects). This means that ingot 4 Prevents cooling water (or rain while stacked outdoors) from accumulating inside the This also prevents problems that would otherwise occur during remelting (e.g. furnace rupture). do. Therefore, in some cases, a preparative solution may be used before redissolution to remove these waters. Necessity of preheating the ingot 40, which was done in a heating furnace, and transporting the ingot to an indoor storage area. can be excluded.

The mold 30 has a bottom wall 32, preferably of a planar profile or rectangular shape (FIG. 2). Structured by a pair of side walls 34 extending in the longitudinal direction and a pair of side walls 36 extending in the width direction. These can be integrally formed or joined using conventional methods to form aluminum or other materials. A mold cavity 38 is defined into which molten metal is poured. Bottom wall 32 and side walls 34.36 is preferably of uniform thickness, e.g. 3 inches), e.g. Manufactured from tile cast iron, etc.

In order to obtain the desired "bottom-to-top" solidification surface characteristics, an important feature of the present invention is that the longitudinal a raised region or ridge 42 extending in the direction; or two widthwise raised raised areas or ridges 44 and 46. It is to have the following. Ridge 42 or longitudinal central axis l! symmetrical to 45 , whereas the widthwise ridges 44,46 preferably extend from the central widthwise axis 47. They are spaced evenly apart from each other. Ridges 42, 44 and 46 inside the mold cavity The top of the is preferably a flat or convex surface, with longitudinal and width The intersection 49 of the ridges is preferably concave in plan view (FIG. 2) and is The solidified ingot can be easily taken out from the bit 38.

A ridge line protruding upward from the mold bottom wall 32 and raised in the width direction or The ridges 42, 44, 46 correspond to the bottom 52 of the large ingot 40 in the longitudinal direction and Advantageous for forming depressions or recesses (48), (50) extending in the width direction . The mold bottom wall 32 is of suitable uniform thickness and has a ridge 42 on the top surface of the bottom wall. 44 and 4G are also connected to the bottom surface 54 of the mold 30. Parts of 48° and 50° are formed. The indentation or recess 48.50 of the ingot 40 is , as well as the corresponding depressions or recesses 48° and 50° on the mold bottom surface 54, Increase the mold bottom area to volume ratio and increase the ridges 42, 44 and 46. By increasing the distance between the covered top surface 56 of the ingot and the inner part of the mold, This effectively promotes solidification from the top of the ingot to the cavity inside the large ingot and its top surface. Reduces the possibility of 56 depressions occurring. Furthermore, high cooling efficiency is a major feature of the present invention. The mold ingot 40 has the same weight but with depressions and depressions 48.50 like the ingot of the present invention. This makes it possible to solidify faster than conventional thin ingots.

The experimental results show that the mold 3 of the present invention has a uniform dimension as described below. In an ingot 40 having a metal weight of 1775 pounds formed in The average time required for solidification of molten metal at Ta. ■Traditional ingots with a metal weight of 0.95 bond are Approximately 3.41 seconds were required for solidification. Rectangular dimensions substantially similar to molds of the present invention Or, unlike the present invention, the bottom wall does not have a ridge extending in the center and width direction. When using a thin mold of 1,515 lb., the ingot weighs 1 lb.

The ingots, which require 13 seconds and weigh 1900 and 2000, are respectively It took 1.52 and 1.50 seconds per code. Therefore, the ingot 40 in the present invention Due to the feature of having depressions extending in the longitudinal and width directions, the height of the ingot ( It is possible to solidify quickly with cooling efficiency of 1, and as a result, it is possible to This allows for faster processing than the type. The solidification rate is 1 degree for the mold, 1 degree for the metal, and It should be recognized that this is related to many factors such as feed rate and the alloy being cast. It is.

A pair of ridges 44, 46 extending in the width direction of the large ingot 30 and correspondingly formed The depression 50 in the ingot 40 is formed by a fork truck as shown in FIG. 1a of the prior art. are separated from each other by a suitable distance equal to the distance between a pair of teeth 25. Furthermore, As shown in FIGS. 5 and 6, the longitudinally extending edge 58 of the mold bottom wall 32 30, extending so as to be continuous with the opposing longitudinal side walls 34 (inside the soil surface of the mold bottom wall). a pair of third raised regions 6 corresponding to the depressions 62 formed on both sides of the central raised region 42; 0, and the bottom of the ingot 40 has a depression of 60° extending in the longitudinal direction (Figures 7-8) form. These holes 62 are located at a distance from each other on both sides of the longitudinal axis of the ingot. a pair of grooves separated from each other and inserted into the recess from a direction perpendicular to one of the sides 64 of the ingot; Suitable raised sides at a distance to receive forklift teeth 25 The shelves are formed in the ingot. In this way, the large ingot 40 of the present invention The teeth 25 of the foot lift the ingot from any of the four sides such as the horizontal side 64 and the vertical side 66. It can be said that it has two-way insertion performance as shown in the figure. This allows the fork truck to ・It is now easier for pick-up workers to lift and place large ingots from both directions. ing.

In the example illustrated in FIGS. 3 and 5, the mold 30 according to the invention includes: The nominal dimensions are as follows.

large mold Nominal size = 76 x 49 and 1/8 x 17 inches Actual size A = 62 and 778 inches Actual size B = 69 and 3/4 inches Actual size C=76 inches Actual size D = 17 inches Actual size E = 4 inches Actual size F=5 inches Actual size G = 9 inches Actual size I (-8 inches Actual size! =25 inches Actual size J = 8 inches Actual size = 3 inches Actual size L = 3 inches Actual size M = radius of curvature 3 inches Actual size N = radius of curvature 3 inches Actual size 0 = radius of curvature 6 inches Actual size P = radius of curvature 3 inches Actual size Q = 17 inches Actual size R = 8 inches Actual size S = 5 inches Actual size T = 3 inches Actual size U = radius of curvature l and 1/2 inches Actual size V = 3 inches Actual size W = 49 and 1/8 inch Actual size X = 3 and l/16 inch Actual size Y-42 and 15/16 inch Actual size Z-20 and 1/2 inch Actual size AA = 9 inches Actual size BB=9 inches Actual size CC = 1 and 1/4 inch The nominal dimensions of the mold 30 as described above include a large mold having a weight of approximately 2000 bonds. It can be used when forming the ingot 40. These dimensions are exemplary and are not used herein. It is possible for those skilled in the art to make appropriate changes based on the following. However, the maximum of invention In order to achieve this effect, a certain relationship is desired between the various dimensions of the mold. That is, large In the mold ingot 40, the central longitudinal (recess 4 8 and the height of the recess 50 extending in the width direction are each indicated by at least dimension G+F. It is a feature of the invention that the height is 25% of the height of the large ingot. Furthermore, large ingots 40, a central longitudinal ridge 49 and a pair of ridges 44 extending in the width direction. ．． The total area occupied by the bottom surface, such as 46, is the size defined by the dimensions rA" x rZJ. It is at least 40% and preferably equal to 50% of the total area of the mold ingot bottom. Big In the mold ingot 40, the width of the raised side shelf 60' indicated by dimension AA is: It is at least 43% of the total width (indicated by dimension Y) of the large ingot. In addition, large casting The length dimension C) relative to the width (dimension Y) of the lump is approximately 1. Whereas it is 6 to 1 However, the ratio of the height dimension F+G) to the length dimension B) of the large ingot is 0. 2? is less than or equal to 1.

As briefly mentioned above, the ridge extending in the center and width direction on the mold bottom W132 The intersection 49 of 42, 44, 48 is preferably smooth and concave and generally If the ingot is mold-like or does not adhere to the mold during solidification and shrinkage, remove the pond. It may be a shape.

The large ingot and mold according to the present invention are similar to the thin mold described above and the one shown in Figure IA-LD. It has many advantages over traditional molds. For example, in the present invention, the thin and the longitudinal and widthwise ridges formed by the ridges 42, 44, 46 on the bottom wall of the mold. The recesses provide better heat dissipation from the central region 70 of the large ingot. this This reduces or prevents the formation of cavities inside the ingot and improves the upper surface 56 of the ingot. The tendency for the surface to become flat is strengthened. In other words, the points of stacking, and the This results in a safer large ingot in terms of preventing pooling. Due to the improvement in heat dissipation mentioned above, , the cooling or solidification time of the ingot for a given metal weight is accelerated.

The flat top surface 56 of the ingot 40 allows for easier stacking. Both of the above Due to the directional insertion characteristic, the ingot can be picked up with the forklift teeth 25 from any of the four sides. This allows fork truck operators to remove the ingot from any desired location. Easy to lift and place.

Furthermore, the mold 30 of the present invention contributes to increasing its own casting weight. Ru. In other words, due to the high cooling efficiency, the mold of the present invention can produce 2000 bonds. Capacity can be easily handled. In addition, higher pouring efficiency Improve your productivity. For example, with - molds, casting or cycle The lifespan of the mold depends on the total number of molds before mold replacement than traditional thin molds. A large amount of ingot aluminum can be produced. Furthermore, high casting efficiency is achieved in one operation. It is possible to cast more metal within a time frame such as a work shift. Noh. Appointment! Many chambers of size can be filled between such It is.

In addition, the large ingot 40 of the present invention has a self-contained structure compared to the conventional type 1 large ingot mentioned above. Contributes to faster heating and melting in the melting furnace. The large ingot of the present invention has a bottom surface The area to volume ratio has been increased and heat is typically reduced during stacking and loading into the furnace. Bottom recess 48.50ε and side shelf 60 that allow heat to reach the bottom of the ingot where it is difficult for heat to pass through. ’, the overall heat transfer efficiency is higher than that of conventional thin large ingots of the same weight. ing.

Another series of experiments compared the casting of 1000 bond ingots with conventional molds. In the case of It has been confirmed that better ingots can be made in terms of ease of rolling and overall appearance. It was done. In experiments, even when using the mold of the present invention, large ingots with internal cavities were produced. It turns out that there is a possibility that it will happen. However, even if proper casting operations are not carried out, Also, the mold of the present invention produced a better ingot than the conventional mold.

One experiment casting metal at 1610 degrees Fahrenheit in a cold mold showed that the conventional 10 The ingot cast in a 00-pound mold has a 0.5-inch depression and two small holes on the top surface. A large internal cavity was formed. 1782 bond cast in a 1500 pound mold of the invention The ingot is 0. Cast with a 2000 pound mold of the present invention with a 5 inch recess on the top surface. The 1858 bonded ingot produced a 1-inch top depression, but none of the ingots No internal cavities were detected.

The ingot cast using the mold of the present invention can be withdrawn within 52 minutes after casting. However, ingots cast using conventional molds were in a molten state in the upper central region. this species It usually takes 90 minutes for the ingot to solidify. The ingot solidified in the mold is The existing aluminum lifting ring placed in the molten metal allows the mold to be removed. It is taken out. If necessary, lifting wedges can be used instead of rings. can.

The present invention may be embodied in other specific embodiments without departing from its spirit or essential characteristics. It may be carried out by Therefore, this example is not limited to all exemplified examples. The scope of the invention should be considered in the light of the above description and not from the attached appendix. is indicated by the scope of the claims, and is attributable to the scope equivalent to or equivalent to the scope of the claims. All changes shall be included within that scope.

Copy and translation of amendment) Submitted Article 184-7, Paragraph 1 of the Patent Act) May 2, 1993 0 days-

Claims (1)

[Claims] 1. A mold for casting molten metal into a metal ingot, the mold receiving the molten metal. It has a bottom wall forming a mold cavity for the mold cavity and a side wall projecting upwardly from the bottom wall. a mold box, the bottom wall protruding into the mold cavity and extending along the length of the bottom wall. The longitudinal cross section corresponding to the bottom surface of the ingot that extends in the longitudinal direction and is formed inside. a first raised region adapted to form an indentation and a first raised region projecting into the mold cavity; A depression with a cross section in the width direction that extends in the width direction of the bottom wall and corresponds to the bottom surface of the ingot. at least one second raised region adapted to form a groove. A mold characterized by. 2. The mold according to claim 1, wherein the first and second raised areas are formed of an ingot. The bottom surface of the ingot has a volume to substantially prevent the formation of cavities within the cavity and the top surface of the ingot. In contrast, the solidified surface in the molten metal is brought into close contact with the mold bottom wall and the first and second raised areas. The ingot is formed in such a proportion that it moves from the bottom of the ingot to the top of the ingot. A mold characterized by. 3. The mold of claim 1, wherein the first raised area is located in the central longitudinal direction of the bottom wall. A ridge or protrusion that extends along the adaxial line and has a raised center; The first raised area has a raised ridge or protrusion shape and is substantially perpendicular to the first raised area. The mold bottom wall also includes a pair of second raised regions disposed on both sides of the central width direction axis of the mold bottom wall. A mold characterized by: 4. The mold according to claim 1, wherein the second raised area is formed on the bottom of the ingot. A continuous depression is formed on the opposite longitudinal side of the ingot. a pair of forks inserted into the recess from a direction substantially perpendicular to one of the opposite side surfaces; They should be spaced apart to accommodate the teeth of the clift and allow for easy handling. A mold characterized by. 5. In the mold according to claim 4, the mold extends adjacent to opposing mold side walls. The edge extending in the longitudinal direction of the bottom wall is approximately perpendicular to one of the widthwise sides of the ingot at the bottom of the ingot. A pair of forklifts that are inserted from the direction of the shelf and enter the bottom of the shelf are A mold is formed to form a pair of longitudinally extending raised side shelves that receive The bottom wall has raised ridges spaced apart from each other on both sides of the longitudinal center axis. A mold forming a pair of third raised areas. 6. The mold of claim 5, wherein the longitudinal axis of the second raised region is , equally spaced from the central axis in the width direction. 7. The mold of claim 6, wherein the central raised ridge is substantially A mold characterized in that the bottom wall of the mold extends over the entire length of the mold. 8. In the mold according to claim 7, the upper surface of the mold bottom wall is located at the front of the mold cavity. characterized by having a recessed portion in the bottom wall between the first and second raised areas. template. 9. In the mold according to claim 8, the surface of the recessed portion in the mold cavity A mold is characterized in that these molds are substantially coplanar with each other. 10. In the mold according to claim 3, the raised ridge at the center corresponds to the length of the ingot. The depression in the hand direction is formed to be at least about 25% of the height of the ingot. A mold characterized by: 11. In the mold according to claim 3, the central raised ridge is located on the bottom wall. A mold, characterized in that it extends over at least 50% of the length of the mold. 12. In the mold according to claim 5, the width of the raised side shelf of the ingot is equal to A mold characterized in that the width is at least about 43% of the total width of the mass. 13. In the mold according to claim 4, the width of the ingot formed by the mold is The ratio of length to length is approximately 1.6 to 1.0, and the ratio of height to length is approximately A mold characterized in that the mold is not larger than 0.2 to 1.0. 14. In large ingots cast from molten metal, the solidification surface of the molten metal is approximately This is the ratio of the bottom of the ingot to the volume that can move from the bottom of the ingot to the top. having a recess extending in the longitudinal direction and a recess extending in the width direction, formed as follows. A large ingot characterized by having a bottom surface of the ingot. 15. In the large ingot according to claim 14, the depression extending in the longitudinal direction is It extends along the longitudinal central axis of the ingot and is also approximately perpendicular to the central depression. and a pair of recesses extending in the width direction arranged on both sides of the center axis in the width direction of the ingot. A large ingot characterized by containing grains. 16. In the large ingot according to claim 15, the pair of depressions extending in the width direction The groove is continuous with the side surface extending in the longitudinal direction of the ingot, and the side surface extending in the longitudinal direction Receives a pair of forklift teeth inserted into the recess from a direction perpendicular to one of the large parts, characterized by being spaced apart from each other so that they can be easily handled Mold ingot. 17. In the ingot according to claim 16, adjacent to a side surface extending in the longitudinal direction of the ingot The edge of the bottom surface extending in the longitudinal direction of the ingot forming a pair of longitudinally extending depressions spaced apart from each other on either side of the line and having a width A pair of forklifts inserted into the recess from a direction perpendicular to one of the sides of the ingot. In order to accommodate the teeth of the A large ingot characterized by forming side shelves in the ingot. 18. In the ingot according to claim 17, the recess extending in the width direction is A large ingot characterized by being equally spaced from the procentric axis. 19. In the ingot according to claim 18, the depression extending in the longitudinal direction of the center is a large ingot characterized by extending over substantially the entire length of the bottom surface of the ingot. 20. In the ingot according to claim 19, the height of the depression extending in the longitudinal direction at the center is A large ingot, characterized in that the height is at least about 25% of the height of the ingot. 21. In the ingot according to claim 20, the depression extending in the longitudinal direction at the center is Large ingot, characterized in that it extends over at least 50% of the length of the ingot . 22. In the ingot according to claim 21, the width of the raised side shelf portion is equal to the width of the ingot. A large ingot characterized by having a width of at least 43% of the total width. 23. In the ingot according to claim 22, the ratio of the length to the width of the ingot is It is approximately 1.6 to 1.0, and the ratio of the height of the ingot to the length is approximately 0.2. A large ingot characterized by not being larger than 1.0.