DE1433032A1 - Method and apparatus for manufacturing rolled metal products from molten material - Google Patents

Description

Method and apparatus for manufacturing rolled metal products from molten metal

(It becomes the priority of the patent application in the United States Ser. No 25 498 of March 21, 1960 claimed)

The invention "relates to the manufacture of metal parts such as "for example steel billets, lobes, sheet iron slabs, in pieces of the desired cross-section, dimensions and weights, directly from the molten metal and without the use of a first or pre-roll.

After "previously known methods steel ingots were cast and stored in pit furnace. Such ingots were then if

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that was required, reheated and put in a roughing mill Free-s-rolled in order to elongate the cast ingot and its cross-sectional dimensions to diminish. As a result, a slab was formed, the length of which was three or more times its largest Cross-sectional dimensions and their cross-sectional dimensions genes were not significantly larger than 500 cm (120 square inches) ο The slabs were then rolled into billets, their Cross-sectional dimensions are not significantly larger than 90 cm (36 square inches) and their length three or more times the largest cross-sectional dimension. Sometimes / ingots are converted into rectangular, elongated sheet iron slabs in a roughing mill rolled, the cross-sectional dimensions of which in the

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On the order of 120 cm (48 square inches) to 900 cm (360 square inches) and three or more times their length the largest cross-sectional dimension. Such Billets and sheet iron slabs were then rolled out further to commercial products such as rods, tubes and sheets.

Previous efforts to make ingots eliminated the need for soaking furnaces by casting slabs or billets, billets (including Tube blanks) and / or sheet iron slabs on commercial Avoid basis were unsuccessful. According to the invention it will enables such lobes, billets (including tubular blanks) and / or sheet iron slabs by means of incline casting can be cast in a long graphite mold and immediately are then to be rolled into commercial products.

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For the purposes of this description, the following definitions are given: "Bulb or slab ¹¹ is a piece of steel that has substantially uniform cross-sections that are not essential

taller than 300 cm (120 square inches) and one length three or more times the largest cross-sectional dimensions.

"Knüppel" (including Eohrrons) is a piece of steel from substantially uniform cross-sections that are not substantially are larger than 90 cm (36 square inches) - and their length three or more times the largest cross-sectional dimension ".

"Eisenbleehbramme" is a piece of steel with approximately uniform rectangular elongated cross-sections measuring from 120 cm (48 square inches) to 900 cm (360 square inches) and from a length three or more times the largest cross-sectional dimension.

It was found that the only casting that succeeds immediately can be rolled into a commercial product without the intermediate stages described above are required, such a casting is the outer surface of which is perfect is free of shrinkage gaps or bites.

Furthermore, it has been found that when such a casting is performed at a temperature which is above the "welding temperature of the metal of the Casting lies, is rolled, the internal shrinkage gaps or Cracks due to internal welding of the metal during the rolling process be eliminated. The rationale for these operations is

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to seek that the oxidation of the surfaces of the outer " Shrinkage gaps or cracks that are influenced by the atmosphere are exposed to irregularities in the surface have consequences that are not eliminated by internal welding " can be. However, if all the shrinkage cracks are within the ingot, oxidation cannot occur, and the rolling brings about a tighter weld, the ■ has the advantage that practically perfect products can be immediate rolling process can be generated.

Furthermore, it was found that a casting with an outer surface, which is free from shrinkage gaps or cracks; can be produced by casting in a permanent mold which causes the outer surface of the casting is completed. In addition to "using a permanent mold is it is necessary to ensure that the end surfaces of the; Castings are also free of shrinkage cracks .. That can caused by a, mold stopper on each other opposite ends of the cavity of the casting mold or that a cloister lock at one end of the cavity the mold is arranged and an.dem other end of the cavity of the Giessfprm a special type of riser is arranged

The main objective of the invention is therefore to provide a method of manufacturing rolled metal parts in which a casting can be rolled directly into a finished metal product without the need for it

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to undertake intervening process steps of the cast bloom and the pre-rolling.

Another object of the invention is a method for the manufacture of rolled metal products in which a casting is produced that is free from external shrinkage cracks or splitting is for immediate rolling, - while its temperature is still above the welding temperature of the metal.

The invention consists in a method of manufacturing rolled Metal products made from molten metal placed in an airtight container, comprising the following steps: An airtight connecting conduit between the container and an inlet at one end of an elongated one Casting mold that consists of eus mold material and on its other end with a riser for sealing internal shrinkage of the casting to a limited depth of the other end of the mold is provided; Applying an overpressure on the metal in the container to push it off the container into the mold; Closing the inlet of the mold with a closing piece made of mold material after the mold is filled; Cutting off part of the other end of the casting in an area above the depth of influence of the riser which is completely free of internal shrinkage cavities after the metal has solidified into a casting in the mold; Heat the casting until its total temperature is above the welding temperature of the metal; and then before the temperature of the casting again below this welding temperature

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falls, rolling the cast iron all internal shrinkage cavities by "internal welding" are eliminated.

The features and advantages of the invention are apparent from the following Embodiments explained with reference to the drawings. In the drawings show:,

Fig. 1 is a perspective view of an embodiment according to the invention, as it is applied "when · Pouring with a common mold,

Fig. 2 is a plan view of a device nach.Fig. 1, FIG. 3 a side view of a device according to FIG. 1,

Fig. 4 is a front view, seen from the right side of Fig. 3 , ■, ·

Fig. 5 is a horizontal section along the line VV of

6 is a plan view of a new embodiment,

7 shows a vertical section along the line VII-Vir of Fig. 6,

Fig. 8 is a side view in partial detail accordingly of Fig. 6,

9 shows a partial section of a vertical axis along the line IX-IX of Fig. 6,

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Pig. Fig. 10 is a side view of the frame of the power device for the closing piece,

Pig. 11 shows a vertical section along the line XI-XI of FIG ! ig. 10,

Pig. 12 is an end view from the left side of FIG seen,

Pig. 14 a plan view of the frame of the striker Schielser,

Pig. 14 a vertical section along the line XIV-XIY of Pig, 13, ·

Pig. 15 a plan view of the closing piece slide,

Pig. 16 shows a vertical section along / the line XVI-XYI the pig. 15,

Pig, 17 a plan view of the striker insert against which the inlet of the casting mold comes to rest,

Pig. 18 shows a vertical section along the line XVIII-XVIII the pig. 17,

Figure 19 is a side view, partially in section, of a billet mold assembly according to the invention, which with the device according to the Pig. 1 to 18 is used,

Pig. 20 shows a horizontal section along the line XX-XX of the Pig. 19

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Fig. 21 a 'Dr on looks at the lower box half of the mold according to Figs. 19 and 20, "- · _.

22 a view "" iron below of the upper box half of the casting mold according to FIGS. 19 and 20, ■■■ _..- : -

Fig. 23 a ^ SO-nfereohten /! DBil-gchiiit ^ "along the--.

of Fig. 21. ..

In each figure certain details are omitted; around a to ensure a clearer overview, and these details are depicted sufficiently clearly in other views ». ■

According to FIG. 1, a casting mold device 2 consists of a casting mold 4 which is formed from a mold material whose: coefficient of thermal conductivity at 18 ° has a value on the order of 0.1 calories per second per cm per ⁰ G per cm or larger. A very; particularly suitable material "" that has such a thermal conductivity is graphite *: / V

The device 2 also consists of a "carriage 6 to which; the mold 4 can be connected by means of customary cleats 7. or by means of gravity. The mold; 4 * and the carriage 6 move during the glazing process ,, as will be described in more detail below, -as-a zwei.zusammen and can unit ± n the desired manner are separated from each ^other.

The carriage 6 has wheels -B, ^ d'ie roll on rails 10 'and is

; .- "'.-" -, -.-. *. ': "den .--. '-; .- .-". furthermore with a piece of Versehliesstück or a / 'Eiiiiass ab-. closing device equipped »generally with 12

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The closure 12 is best shown in the I ¹ Ig. 6 ″ to 8 and 13 ″ to 18 shown, and it consists of a S c hie "be guide 14 with an opening or through-hole 15 in which a bush 16 is seated (FIG. 7) made of any suitable material, such as Graphite, baked clay, or lining stoneware. A cutout or slot 18 (Pig. 13) is formed in the slider guide 14 and is defined in part by an inner edge 20 for a purpose described below.

A slide or a plate 22, preferably made of cast iron, copper or another suitable mold material that the above-mentioned value of a low coefficient of thermal conductivity is slidably attached to the guide 14 and has an opening or inlet 24 with a socket 26 which is similar in shape and material composition to that of the bush 16. The slide 22 is connected to a channel 28 (FIG. 14) of guide 14 and sits along surface 30 the channel immediately below the shoulders or shoulders 32> which form another channel 34 in which a loose insert 36 sits (Fig. 6 to 7 and 17 to 18), which is inserted removably into an opening 38 of the top plate 40 of the carriage 6 and in his Shape matches the shape of the opening.

The slide guide 14 is detachably connected to the plate 40 with the aid of eyelets 42 on the guide, which have openings 44, in the lugs 46 on the underside of the plate 40 be included. The lugs 46 are slotted for receiving

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of locking wedges 48, which in the closed position shown in FIG can be driven in and quickly by one blow against the sehmale end of the wedges 48 can be removed.

The insert 36 has an opening 50 with a socket 52 (Fig. 7) which the sockets' 16 and. 26 is similar in shape and material, the openings 15, 24 and 60, when they are aligned with one another, form a continuous inlet for the flow of molten metal into an inlet conduit 54 (FIG. 7;) of the casting mold 4. : .- -..--- * ■ -... - · _ -

The device 2 rolls along rails 10 until one of the wheels hits a retractable holding part 56 (Fig. 4). This holding part is pivotably articulated at 55 with an eyelet 57 on the rail section 10a in order to bring the openings 15, 24 and 50 into position in a vertically aligned position one above the other and by means of the head piece of a pouring pipe 58. The lower end of de ^- s G-iessrohres communicates with a source of material to be cast, such as-for example, a ladle with molten metal, which is not shown here, in connection. These are the conditions in which they sit; Wheels 8 on rail parts 10a, which are to be separated from the rail track 10 and are to be moved vertically.

The rail parts 10a sit on a frame 60, which in turn at its corners by conventional spindle and spindle nut lifting gear 62 connected to a bidirectional electric motor 64 is carried. The lifters are on beams 66 protruding from the foundation (Fig. 3 and 4)

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attached and raise or lower the frame 60 according to the Rotational movement of the shaft 68 of the motor 64 in one direction or the other. The frame 60 is guided by rollers 70 (Fig. 2 and 3), which are stuck to the frame and vertically out of the ! Foundation towering beams 72 cooperate. The car will on each of its sides in line with the head of the Pipe 58 through guide rails 71 seated on the foundation (Lig. 1) led into one formed between them Slot to receive a pin 73 on the plate 40 of the carriage 6.

With the device 2 aligned with the head of the tube 58, the motor 64 is started to lower the frame 60 until a conical inlet 74 in the bottom of the slide guide 14 looks onto a complementary conical portion 76 on the top of the Tube 58 touches down. The frame continues to move downward until the slide guide 14 is stuck against the conical portion of the tube 58 by gravity or other means (not shown here) so that an essentially airtight connection between the tube and. the slide guide 14 comes about »Thereupon the metal into which the tube 14 is immersed is put under pressure, for example in the manner _x as that in the US patent ITr. 2,847,739 of Aug. 19, 1958 - EQ Sylvester to force the metal upwardly through openings 15, 24 and 50 and inlet 54 until the mold is filled. Doughing of the carriage 6 during the semolina process is limited by the shoulders 75 (FIG. 1) which are attached to supports and are described in more detail below.

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When the -jorm is filled, the slide 22 is operated as will be described below to the near flow of molten metal through the entrance, and then the * Pressure on the molten metal subsided, the rail sections 10a are lifted up until they are back with the rail track 10 stand together, and the door direction 2 is along the Rail track over the holding parts 56 ;. rolled away that in ineffective. would be pivoted. The holding part 56 is then again swiveled into the effective position, and another door direction 2 is placed in position and poured as described above.

The way in which the closing piece 12 is operated can, best from the lig. 8 and 10 to 12 can be removed; there it can be seen that if the gate device 2 on the head of the tube is <58%, a power-operated gate device 78, which sits on the cover 80 of a container -81 for molten metal, is located between the slide 22 and- has pushed a stop SZ from. the underside of the plate 40 protrudes »When the gate direction 78 is actuated, be it by hydraulic or pneumatic pressure, to push the gate direction 78 apart in the axial direction, a cylinder part 84, 'of the gate direction 78, moves against the block 82 applies and a sol \ benteil 8 "β of Torrichtung 78 abuts against the Schliesstüeksichieber 22 ^{.Torfichtung;.} ^ 78 -weiät eineii only limited stroke on, and- at the end / * stroke is the slider 22 in a position ^ in which its opening; 24; over the 'edge 20 of the slide guide 14 Mnülaer. ^ is pushed, whereupon _{: the} face of the metal ■■ in. " the opening; 24

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falls out through the recess or slot 18 so that the Socket 26 does not have to be replaced for every Q-essvorgang "Needs. Relieving the pressure on the molten metal in the container 81 "also causes the metal in the Bushing 16 falls back so that this bushing does not need to be replaced for every casting process either.

The device 78 is cantilevered or floating, so that when actuated, the forces generated by this device 78 to move the closing piece 12 in the closed position within the device 2 are short-circuited, so that a closed force flow is present; This "special attachment consists of a carrier 88, which is on the cover 80 through Welding is attached at 90. The carrier has a V-shaped channel 92 in which a correspondingly complementary shaped slide 94 is seated. The cylinder part 84 is through with the slide 94 Pinch rollers 98 connected to levers 100 which are pivotable at 102 are hinged to the slide 94 and are brought to clamp by a compression spring 104. A pin protrudes from the slide 94 106 down through an elongated slot 108 of the channel 92 and is connected to a tension spring 110 for alignment, which, after the device 78 has been discharged, a collar 109 of the cylinder part 84 against a holding plate 111 on the carrier 88 pushes and thereby the cylinder part 84 yielding in the correct The position in the space between the slide 22 and the stop 82 holds when the device 2 is out of the position shown in FIG. 8 position shown lifted or lowered into this position.

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After starting device 78 as above is described, allows the slide 94 sufficient axial movement for the / device 78 so that developed there Forces within the device 2 are short-circuited in closed flow, and practically no reaction force on the Carrier 88 or the cover 80 is transferred.

After removing the cylinder84 from the clamps 98- that can by hand, by lifting: the cylinder and pressing the Every 104 done - will be the spring. 104 held in position on lugs 112 on levers TOO by a weak force; which comes from a tension spring 113 connected to the lower ends of the Lever 100 is connected. ; : .. -...-;

It should be mentioned here that the cover 80 with the upper part of its container 81 through brackets, not shown here connected to the beams supported in the foundation 114 sit, and the rail parts 10a can by hand from the Frame 60 can be removed and also put on to use and removing the lid 80 and a non-illustrated Gdesspan with molten metal * in which the tube 58 flows out to facilitate. The structure of the container 81, the cast pan (not shown here), the cover 80 and the tube 58 is not the subject of the present invention and can be used in made of the type Hein, such as that in the -cited US patent. font is shown, it can also be any other expedient Construction be carried out, wherein the tube on the cover or · elsewhere in connection with the; molten metal in the

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Container 81 stands and is attached.

It should be noted that the sockets 16, 26 and 52 on their upper ends are flanged so that in Pig. 7, the flange of the socket 16 in the aligned position shown the slide 22 lies, the flange of the bushing 26 against the insert 36 is and the flange of the socket 52 against the mold 4 is located around inlet 54 »

In FIGS. 19 to 23 a mold device is shown, which according to the invention a special billet casting mold device 116 has for casting steel billets that are used in commercial products can be rolled such as wire or rods without any intermediate process step such as forging or roughing.

The casting device 116 consists of an upper frame 117, which is formed by long side beams 118, which are fused with cross beams 120 and 121. The upper half of the box 122 of the mold is formed from one or more blocks 124, those made of mold material, for example graphite, with the characteristics of thermal conductivity described above exist. These blocks are clamped against angles 120 and 121 with clamping pieces 126 and screws and nuts 128. The blocks 124 are further secured by a clamp 130 and bolts and nuts 132 (one of which is on the left side of the Fig. 19 is shown) stretched against a stop angle 134, which is welded or otherwise fastened to the frame girders 118 is.

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The casting mold device Ί 16 "still consists of a lower one Frame 136 formed by long side beams 138 is that with long angle iron 14: 0 and transverse angles 141 and 143 are welded. The lower half 142 of the mold consists of one or more blocks 144 made of mold material and lies against the angle 140 and is secured by a clamping piece 1.46 and bolts and nuts 148 (one of which is shown on the left-hand side of FIG. "1" 9) clamped against a stop bracket 147 which is attached to the frame 136 by welding or. "" is "" attached "in some other way. \ ..

The frames 117 and 136 are connected to one another by means that can be easily separated from one another, such as screws and nuts 149, for example, so that: the upper 122 and lower box halves are clamped together and a casting cavity 151 in the form a conventional stick form, of between 5 m and 7 »50 m: is long (30 20And foot) and approximately square cross section ite of dimensions of between 5 and 15 cm (2 and 6 inches) at a _Se: ^':.; '

that the. end of the casting, that the Inlet opposite the casting cavity, free of Schwih.dimgsrissen remains ,, a special riser arrangement is required.

That; upper end; The gate is provided with: a block 148a of coconut material: which has the thermal conductivity properties given above, such as graphite, and an opening; - 150 - which is in contact with the mold cavity t5t; steitt and ^ on the other hand the

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Connects to a riser cavity 152 of another block 148b made of the mold material. This block 148b is clamped over the block 148a by bolts and nuts 153 (one of these bolts and nuts is shown on the left-hand side of I ¹ Xg, 19).

"The lower end of the upper flask 122 is with a block 152 made of mold material. The block 152 has an inlet conduit 155 which connects to the lower end of the casting cavity 151 is in communication and this with the openings 15, 24 and 50 (Mg, 7) of the shutter 12 connects to a carriage 2a. These Arrangement is essentially the same as that with the carriage 2 described above, with the exception that the carriage 2a preferably has only one pair of wheels 8a because the lower half of the molding box 142 is pivotably mounted on a pivot bracket 154 at its opposite end. This swivel bracket is welded to the supports 138 and is pivotable in-öinem V-shaped support 156 of a carriage 158, its wheels 160 run on the rails 10. The rail parts 10a and their Lifting and lowering device as well as the casting and locking devices are shown and described in Figures 1 through 18, and are not in detail in the i'ig. 19 and 21 reproduced »

It can be seen that when the rail sections 10a from « be lowered to connect the inlet 155 to the measuring tube 58, as described above, a pivoting movement between the device 116 and the rail sections 10a

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takes place, specifically, with the help of the wheels 8a, and there is also a pivoting movement between the carriage 158 and the. Device 11.6 instead, with the help of the viewing pivot bracket 154.

In practice, billets and sheet iron slabs have been cast "at a metal flow rate of about 65 pounds per second. These billets were approximately 30 3 ½ feet long and had a square cross-section Not more than 8.1 cm (3 1/4 inches) on a side., The upper 122 and lower box halves, which form the die in which such billets were cast, were formed from graphite blocks which were machined on their superposed surfaces 20 to form the mold cavity 151. It has been recognized that graphite forms a very fine dendritic structure on the surface of the casting, and according to the invention it is extraordinary It is essential that both the casting mold and the riser as well as the closing piece 22 consist of a material which has the thermal conductivity properties described above, namely a coefficient of thermal conductivity with a value of at least 0.1 calories per second per cm per ⁰ C per cm, so that products such as slabs, billets or flakes, which are to be rolled immediately afterwards, can be poured under bridge. .; . '

For a semolina form with a cavity of about 7.50 m (30 puss) length or more is the longitudinal axis of the Gdessform preferably at an angle in the order of magnitude of 24 °

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or less in relation to the horizontal.

To the whole process of manufacturing a rolled metal product according to the teachings of the invention to describe, it should first be noted that the casting is initially through Pressure casting from below under non-turbulent flow conditions is generated, as described above ", with the application of superatmospheric pressure on the metal in the belSLter.

After the mold and the riser cavities are filled and the molten metal flows into the mold cut off the pusher device described above the casting is allowed to cool to the point where it has solidified enough to be removed from the mold.

It should be noted that up to this process step, the entire outer surface of the casting with the Exception self-understanding of the surface of the riser, which was exposed to the open atmosphere, with the inner surface of the

Casting mold made of chill material and / or the closing piece has been in contact 'and therefore completely free of extraneous Shrinkage gaps or cracks. Due to the riser arrangement is the belt part or the upper end of the casting up to a depth of several centimeters free of shrinkage cracks.

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Now the rising end of the casting is cut off in order to remove the pouring funnel or the lost head and to obtain the desired length for the casting. The casting is cut in the part that is free from shrinkage cracks so that the outer end face of the casting is like the. Rest of the surface of the casting, is free of shrinkage voids. ■ " _: · '- ■

Sails- the total temperature of the casting "up to. ^ Maintains the - ,, _; -Welding temperature of the metal; has fallen, and. That is usually the Sail, the casting is heated again until its total temperature is above the welding temperature des- metal-, les lies.- ■■■■ ""-.-.;._; ■ Λ ^; ,: / - '. """." ^{': V;;} ■.. -" ■. _^::: ·. _; _; ■; ■ -.-. "

The casting is then ready to be rolled directly into commercial products. During the rolling process, any internal shrinkage giants or gaps are welded in the casting, namely by the rolling process itself, so that a finished product is obtained that is completely free of has internal irregularities and a perfectly uniform "■ '" construction ·; ..-. ". '':" .. , "-""-.':^;.""."V;;;"'^ ^ -.-'- · ■■ -

Claims (8)

'■ H33032 (2Ta] G UTE RS LO H I. W-, the 5th · .. HoTfB ^!?.? .. 1960 Wilhelmstrasse 4 claims 1.) Method of manufacturing rolled metal products from molten metal, which is in an airtight container (81) is located, characterized by the following process, stepet establishing an airtight connection (58) between the container (81) and an inlet (155) at one end of an elongated casting mold (4) which consists of mold material and at its other end is provided with a riser (150, 152) for sealing in the event of internal shrinkage of the casting to a limited depth from the other end of the form} applying positive pressure to the metal in the Container to take the metal from the container into the mold press j. Closing the connection (155) with a sealing piece (22) made of mold material after the mold is filled! after the metal has solidified into a casting in the form of cutting off of one! part from the other end of the casting in an area above the depth mentioned, which is completely heating of the is free of internal shrinkage increases • the casting until its total temperature is above the welding temperature of the metal lies; then, before the temperature of the casting has fallen below its welding temperature again, rolling out the casting until all internal shrinkage cavities are eliminated by internal welding. 909836/0358 2.) The method according to claim!, "Characterized» that the Coefficient of thermal conductivity of the mold material at 18 ° Q a value in the order of 0.1 calories per Second per cm pr® 0 per cm or greater. 3.) Method according to one of the preceding claims, - characterized in that the coefficient of thermal conductivity of the material of the sole set (22) at 18 ° C ■ - ■■■ - ■ "■ 2 Has a value of the order of 0.1 calories per second per cm per ⁰ O per cm or greater. 4.) Method according to one of the preceding claims, characterized indicated that the material of the mold is graphite 5.) Method according to one of the preceding claims, characterized in that the material of the Sehliesstückes is metal. 6.) Method according to one of the preceding claims, characterized characterized in that the shape lies above the container and the molten metal is pressed out of the container into the mold against the effect of gravity, 7.) Method according to one of the preceding claims, daduroh characterized in that the shape with its longitudinal axis in one Angle to the horizontal is inclined, which is less than 90 °. 8.) Method according to one of the preceding claims, characterized by the process step that the casting before the Rolling is reheated until its temperature is above the welding temperature of the metal.%.,. 90983670358