DE2011434A1 - - Google Patents

Description

8000 MOnch.n 60, t OL HRZ. 19Λ Γ \ 11 / Ο /

Dipl.-Ing. Egon Prinz -sr ».i» r _e .r.tr «.,. I9 ZViI **. O**

Dr. Gertrud Hauser Dipl.-Ing. Gottfried Leiser

Patent attorneys

Telegrams: Maze monks

Telephone: 83 15 10
Postal checking account: Munich 117078

Us he signs: S 2f? 46

SOUTHWIEE 'COMPANY
1.26 .Fertilla Street ■
Carrollton, Georgia /Y.St.A.

Procedure and. Device for pre-cooling a continuous Casting machine

In a casting machine with a rotating casting wheel that has a circumferential groove, and a continuous flexible band that is placed on the groove and is with the casting wheel moved over a substantial arc of its rotation to an arcuate, moving one Forming mold is usually a liquid coolant, such as B. water, is supplied to the outer surfaces of the mold while the molten metal is solidified. Applying the coolant to the outer surfaces of the mold increases heat transfer to the molten one Metal and the solidification speed of the metal and protects the mold against destruction by heat * The casting wheel and the flexible band are very sensitive in the part of the arcuate shape where the molten metal in the mold is poured because the molten metal is hottest at this point and the casting wheel and the Tape can be heated from a relatively low temperature to an extremely high temperature and expand very, quickly.

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When the operator of a continuous casting machine initially puts that machine into operation, it usually causes the casting wheel to rotate slowly and the molten metal into the mold cavity flows in at a relatively high flow rate until a melt pool of the molten metal and then it adjusts the flow rate of the molten metal and increases the flow rate Speed of rotation of the casting wheel while the molten metal pool is maintained. The usual length of time between the initial pouring of the molten metal into the arcuate mold, which is formed by the casting wheel and the flexible belt and the application of the liquid coolant the outer surface of the arcuate shape is about 15 seconds. During the initial pouring of the molten Metal in the arcuate shape, the casting wheel and flexible tape are usually cooler than one Time when the machine has been running for a certain amount of time, as the machine initially has a considerable amount of time Part that will maintain its own room temperature, and the molten metal will initially be in the arcuate shape Solidify the shape without the need to apply liquid coolant. The shock of heat transfer from however, the molten metal on the material of the relatively cold casting wheel and flexible belt is considerable and causes significant destruction of these materials that would not occur if the mold surfaces were to be would be continuously cooled during start-up.

During this start-up process there is a considerable risk that the melt pool of the molten metal

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is imprecisely controlled and the shape overflows. When melted Metal comes into contact with the coolant, causing a violent explosion. Therefore, the operator leaves the casting machine usually creates the melt pool of the molten metal in the arched shape, before it lets the coolant get onto the outer surfaces of the casting wheel and flexible belt, and avoids carefully overflowing the form, and. despite the damage caused to the casting wheel and the belt as a result of the Delay in the coolant supply is added.

The present invention relates to a method and a Device for cooling a continuous casting machine, with liquid coolant before and during start-up operation is fed to the casting machine without a significant risk of explosion as a result of the overflow of molten metal from the casting machine or from wet Form surfaces consists. The liquid coolant is applied to the flexible belt and to the casting wheel in places at the Applied outer surfaces of the arcuate shape, where the likelihood that the coolant will be low inner mold surfaces prior to initial pouring of the molten metal touches, and where an overflow of molten metal is unlikely to touch the liquid coolant. The coolant is applied to the flexible tape with a small amount and speed by means of a fine nozzle arrangement between the band arrangement roller and the band, by means of the band collecting tube, which is arranged directly in the height of the fine nozzles and applied through the wheel collecting tubes of the first stage. Although the coolant is applied in a small amount and at a low rate, it is combined with the

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remaining room temperature of the casting wheel and the flexible Tape is effective to protect these elements against heat deterioration during the initial pouring of the molten To protect metal for a period of time that would be required by the average operator of a metal casting machine sufficient to produce the molten metal pool in the arcuate shape and to start the caster at operating speed bring to.

It is therefore an object of this invention to provide a method and apparatus for cooling a continuous To create casting machine before and during the initial stages of metal casting without significant explosion hazards occur as a result of inadvertent mixing of coolant with the molten metal.

Another object of this invention is to provide a pre-cooling system for a continuous casting machine, this works to protect the casting wheel and the flexible belt against unintentional metal fatigue and destruction during to protect the initial operation of the machine.

Another object of this invention is to provide a method for cooling a continuous casting machine, in which the operator uses the machine for an extended period of time during the initial operation of the Machine can operate without using the main cooling system without the risk of the machine overheating.

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Further objects, features and advantages of the present invention will become apparent from the following description in connection with the drawing. Show in it:

Fig. 1 is a side view of a continuous casting machine, with some parts omitted for clarity;

Fig. 2 is a detailed view of the part of the casting machine according to Fig. 1 in which the flexible tape is initially comes into contact with the circumferential groove of the casting wheel;

3 shows a section through the casting wheel and its coolant collecting pipes, along the line 3-3 in Fig. 2, and

Fig. 4 is a front view of the fine nozzle and the upper one Part of the upper tape collection tube, taken along lines 4-4 in FIG. 2.

From the drawing, in which like reference numerals are the same Identifying parts in all figures, Fig. 1 shows a Casting machine 10, which has a casting wheel 11, a continuous flexible tape 12 and tape placement rollers 14a, 14b, 14c and I4d. As shown in Fig. 3, the casting wheel 11 consists of an assembly including a rotatable support plate 15, assembly edges 16 and 18 and a mold ring 19 includes. The shaped ring forms an outward-facing, annular circumferential groove 20 which has an inner wall 21 and inclined side walls 22. The continuous flexible tape 12 closes the circumferential groove 20 to form an arcuate mold cavity that extends around the the lower part of the casting wheel 11 extends around.

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As best seen in FIG. 2, the tape arranging roller 14a operates around the continuous tape 12 to move into contact with the mold ring 19, and an inlet spout 24 protrudes into the semicircular shape, which is formed by the band 12 and the shaped ring 19. The inlet spout 24 is used to get molten metal in the semicircular shape from a ladle 25 (Fig. 1) to fill so that a molten bath from the molten Metal is formed. The flow rate of the molten metal from the ladle 25 through the spout 24 is regulated so that the upper mirror 26 of the molten metal pool is normally the lower End of the inlet spout 24 covered to cause turbulence of the molten metal in the semicircular shape to decrease.

The tape arranging roller 14a has a pair of annular ones Grooves 28 and 29 (Fig. 4), and a fine array of nozzles 30 is in close proximity to the tape assembly roller 14a arranged and protrudes into the grooves 28 and 29. The fine nozzle assembly 30 is of the type shown in FIG U.S. Patent No. 3,333,629 and has a feed line 31 and a pair of spaced apart arranged wedge-shaped nozzles 32 and 33 which protrude into the annular grooves 28 and 29, respectively. The feed line 31 has openings 34 in the nozzles 32 and 33. The nozzles 32 and 33 each include a nozzle front plate 35, which is made with a curvature corresponding to the curvature of the outer surface of the mold ring 19, and several Nozzle openings 36 extend through the nozzle faceplate 35. The nozzle openings 36 are shaped so that that they are directed substantially in the downward direction from the tape arranging roller 14a, and that through the

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Coolant passing through the openings 36 flows mainly only in the downward direction. The upper ends of the nozzle face plates 35 are in the annular grooves 28 and 29 of the tape arrangement roller 14a arranged so high that as is convenient, and the top wall 38 of the nozzles 32 and 33 is formed with a curvature substantially corresponding to the inner surface 39 of the grooves 28 and 29.

An upper band collecting tube 40 is arranged immediately in the vicinity and below the fine nozzle arrangement 30 and extends in the downward direction around the casting wheel 11. A lower tape collection tube 41 (Fig. 1) is immediately in located near and below the upper tape collection tube 4P and extends further in the downward direction and ends approximately under the casting wheel 11. A rear strip manifold 42 extends from the lower part of the casting wheel 11 up to the tape assembly roller 14d, and a rear one fine nozzle assembly 44 protrudes between the ribbon assembly roller 14d and the casting wheel 11 in a similar manner such as the nozzle assembly 30 between the ribbon assembly roller 14a and the casting wheel 11.

A pair of side manifolds 45 are disposed on opposite sides of the arcuate mold and extend downward from the entrance of the arcuate mold to the bottom portion of the casting wheel 11 and the like lateral collecting tubes 46 extend from the lower Part of the casting wheel 11 upwards to the exit part of the arcuate shape.

Casting wheel headers 48, 49 and 50 are near the rotatable support plate 15 arranged approximately in the same plane as the mold ring 19 »Die Gießradsammelrohre 48, 49 and

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50 each extend over an arc of approximately 90 ° around the casting wheel 11 from the band arrangement roller 14a over the lower part of the casting wheel and up to the band arrangement roller 14d. A plurality of nozzles 51 extend from the outer curved portion of the casting wheel manifolds 48, 49 and 50 and serve to spray coolant onto an inner surface 52 of the mold ring 19. As shown in Fig. 1, the liquid coolant, such as. B. water, the fine nozzles and the manifolds of the casting machine 10 via a main line 53 is supplied. Several branch lines extend from the main line 53 and are in communication with the various nozzle assemblies and headers. A branch line 54 is in communication with the fine nozzle arrangement 30, a branch line ^ is in communication with the upper band collecting pipe 40, a branch line 56 is in communication with the lower band collecting pipe 41, a branch line 57 is in communication with the rear band collecting pipe, branch lines 58 and 59 are in communication with the side manifolds 45, and branch lines 60 and 61 are in communication with the side manifolds 46. Each branch line has a manual control valve which is used to regulate the flow of coolant from the main line i? 3. A branch line 62 extends from the main pipe 53 and is connected to a central terminal 64 for the slide Gießradsammelrohre 48, 49 and ^ O. The slide port 64 has control slide valves 65, 66 and 67 which serve to control the flow of coolant from the branch line 62 into each of the casting wheel manifolds 48 and 49 and 50, respectively.

A main control slide 70 is arranged in the main line 53 and serves to control the coolant flow through the

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Main line 53 through to the branch lines 54 to 62 to control. The main control slide 70 becomes pneumatic controlled, and the flow of the actuating fluid to one pneumatic control motor 71 is controlled by a solenoid Valve 72 regulated. -

A main branch line 73 is with the main line 53 upstream of the main control slide valve 70 and bypass lines 74, 75 and 76 are between the Main shunt line 73 and branch lines 54 and 55 or the casting wheel collecting pipe 48 is connected. The openings of the bypass lines 74, 75 and 76 are also controlled by manual control slide. Check valves 78 and 79 are in branch lines 54 and 55 located upstream of the connections between these lines and their respective branch lines 74 and 75 exist. Similarly, a check valve (not shown) is disposed in the spool port 64, to flow coolant from the casting wheel manifold 48 back to the valve port 64 and the branch line 62 to prevent. The coolant flow through the main bypass line 73 is controlled by a solenoid operated valve 80.

Way of working

When the operator wants to start continuous casting of metal in the casting machine 10, he guides the usual start-up processes that require the heating of the Metal in an oven to a temperature of over 1093 ° C, preheating the cleaning device and of the ladle, adjusting the belt tension, that Drying the belt and wheel to ensure

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that there is no moisture on these surfaces, and include various other preparatory work. That Valve 80 of main bypass line 73 is opened, allowing liquid coolant to flow through the main bypass line 73 is routed to the bypass lines 74, 75 and 76. The manual control valve of the bypass line. 74, 75 and 76 are preset so that the coolant with low speed and amount of the fine nozzle arrangement 30, the upper Bandsammeirohr 40 and the Gi eßradsammelrohr 48 is supplied. The coolant occurs from the nozzles provided on these manifolds and is applied to the outer surfaces of the semicircular shape upset. The coolant flowing through the nozzle assembly 30 becomes approximately downward along the outer surface of the belt 12 passed. Since the upper parts of the nozzles 32 and 33 of the nozzle assembly 30 in the annular Groove 28 of the tape arrangement roller 14a are inserted, the coolant flow in this area is on the annular Rage 28 and 29 of the tape arrangement roller 14a limited, until he gets out of the grooves 28 and 29 to the relationship between the nozzle faceplate 35 and the outer surface of the belt 12, which extends downward from the ribbon arrangement roller 14a. Thus serve the direction in which the coolant emerges from the nozzle openings 36 and the subsequent features of the annular grooves 28 and 29 of the tape assembly roller 14a to prevent Coolant flows into the mold cavity, splashes or sprays through the circumferential groove 20 of the casting wheel 11 and the belt 12 is formed.

The upper openings of the nozzles 51, which extend from the casting wheel manifold 48 extend out are carefully directed downward within the casting wheel 11 so that the out

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Coolant exiting these nozzles cannot flow, splash, or spray into the mold cavity. aside from that the nozzles 51 are directed against the inner surface 52 (Fig. 3) of the mold ring 19, and the arrangement edges 16 and 18 serve to control the jet of the jet emerging from the nozzles 51 To limit coolant to the inner surface of the mold ring 19.

Since the upper tape liner tube 40 against the nozzle assembly 30 is offset downwards, there is little or no risk of coolant from the nozzles of the upper band collecting tube 40 comes into contact with the surfaces of the arcuate shape.

The manual control valves of the web flow lines 74, 75 and 76 are regulated so that a relatively small volume and a relatively low flow rate of coolant from the nozzle assembly 30, from the upper Band collecting tube 40 and from the casting wheel collecting tube 48 is created to further reduce the possibility of coolant accidentally splashing or spraying on the surfaces of the arcuate shape. The check valves 78 and "79 in the branch lines 54 and 55 and the check valve in the spool connection 64 prevent that Coolant during the initial coolant flow through the entire system from the main bypass line 73 from flowing through it. Of course, these check valves open, when the main line 53 is switched on by the main spool valve 70.

When the operator is ready to start casting start, it turns the casting wheel with a relatively low

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and adjusts the pouring pan's metering pin to pour a relatively large amount of molten metal into the semicircular shape until a molten metal pool is formed. It is desirable that the molten metal pool mirror 26 cover the open end of the spout 24 so that there is a minimum of turbulence in the molten metal contained in the mold. When the operator has made the molten metal pool, the main control valve JO of the main line 53 is opened by energizing its solenoid, and coolant flows in a larger volume and at a higher speed through the various branch lines 54 to 62, around the nozzle assemblies 30 and 44 and to supply the manifolds 40, 41, 42, 45, 46, 48, 49 and 50. As a result, the coolant which is already flowing out of the nozzle arrangement 30, the upper band collecting tube 40 and the casting wheel collecting tube 48 increases its speed and its volume immediately when the remaining collecting tubes are switched on. At this time, the angular speed of the casting wheel is increased to cast metal in a larger amount.

The pre-cooling during the initial casting, before the main coolant flow is turned on, gives the Operator the ability to bring the casting wheel to normal speed now, even before the main coolant flow is supplied usually a time delay of about 3 seconds between the moment the operator does the The main spool solenoid energizes and the coolant flows through the various nozzles completely

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the manifolds takes place. Although this time lag so far was a bit critical with the known systems and before had to be compensated for by the operator, it is in the precooling system according to the invention less important as the pre-cooling system serves to reduce the Mold destruction and damage significantly due to the initial Reduce heat transfer in the casting machine.

At this point it should be understood that the casting wheel manifold 48 and the upper band collection tube 40 serve to remove the cooled area of the mold from the inlet spout 24 and the nozzle assembly 30 down to expand the lower part of the casting wheel 11 during the preliminary stages of casting, and that the low angular velocity of the casting wheel during this casting stage gives the opportunity to use up the heat of the molten metal within this length of the casting wheel path, so that the metal is at an acceptable temperature, which does not damage the materials of the casting machine. Thus, there are risks of operator error considerably degraded without normal function affect the machine. - -. ■■

Although the invention has been explained such that it is controlled by manual control of the circuits of the valve solenoids, the system eigejjnt for an automatic operation program in which the main spool ¹ JO is opened automatically after the bypass valve has been opened 80th For example, a circuit has been developed to open the main spool valve 70 after the bypass valve is initially opened

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a predetermined amount of time has elapsed to open the main spool valve 70 when the temperature of the casting wheel has reached a predetermined height, and to open the main control valve 70 when a Melt pool of molten metal at the entrance of the arcuate shape by a nuclear radiation metal mirror sensor has been established. Obviously, combinations of these arrangements and various other automatic control arrangements can be developed.

The circuit was designed for an automatic start-up system in which the flow rate of the molten Metal, the speed of the casting wheel and the cooling water are controlled automatically.

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Claims (1)

201 U3A Patent claims: 1. A method of continuous casting of metal, in which the metal is in a molten state into a semicircular shape Mold is poured through a circumferential groove of a rotatable casting wheel and a continuous flexible belt is formed, characterized in that first a coolant with relative low volume is applied to parts of the outer surfaces of the mold while the mold temperature increases as a result of heat transfer from the molten metal during the initial casting stages, and that then the volume of the coolant flow to the same parts of the outer surfaces of the mold increased and additional coolant volume to others Parts of the outer surfaces of the mold are conducted while the mold temperature after the initial Casting stages increases. 2. The method according to claim 1, characterized in that in the step of initially applying a coolant with a relatively low volume to parts of the outer surfaces of the mold, the coolant is applied to the parts of the outer surfaces of the mold prior to any increase in the mold temperature and that the application of the The low volume coolant is continued during the initial casting stages. 3. The method according to claim 1, characterized in that that in the step of initially applying coolant, the coolant is initially through a : -16- 009839/1533 201H3A fine nozzle arrangement is applied in the vicinity of the flexible tape at the point where the flexible Tape touches the casting wheel first, and the coolant is applied to the flexible tape while it runs through the first part of its arc of movement with the casting wheel. 4. The method according to claim 1, characterized in that that in the step of applying additional coolant volume, the coolant on the side surfaces of the casting wheel is applied. 5. Apparatus for performing the method according to claim 1, with a rotatable casting wheel having a circumferential groove forms, and a continuous flexible band that closes part of the groove to a Form arcuate shape characterized by combining with multiple spray devices for liquid Coolants, which are attached near the arcuate shape, to liquid coolant to apply the outer surfaces of the mold, and flow control devices to apply the coolant through at least one of the spray devices having a first predetermined flow volume and optionally with a second predetermined flow volume. 6. Apparatus according to claim 5, characterized in that that the spray devices have a first strip manifold, which is arranged in the vicinity of the belt and extends from the point where the belt first touches the casting wheel, extends to the lower peripheral portion of the casting wheel, a second band collecting tube, which is in the vicinity -17- 009839/1533 of the belt is arranged and is from the lower um- " to catch section of the casting wheel until the point extends where the tape separates from the casting wheel, a pair of lateral ones Manifolds, which are arranged on opposite sides of the casting wheel and each from the point where the strip first touches the casting wheel, extend to the lower portion of the casting wheel and comprise a plurality of inner headers, which extend around the inner surface of the casting wheel from where the ribbon first contacts the casting wheel to where the ribbon "extends" releases from the casting wheel, and that the flow control devices have slide to at least one of the Headers with the liquid coolant under one to load first print and to optionally at least this one and the remaining headers with the liquid Charge coolant with a second pressure. Device according to claim 6, characterized in that that the spool valve has a first spool valve that is connected between a source of pressurized . Coolant and all manifolds are switched on, .a second control slide, which is placed between the .source ; of the pressurized coolant and at least one of the headers is turned on, and include check valves associated with at least one of the headers are in communication and are arranged so that they prevent coolant from at least the one of the headers flows to the other headers. . . ' 8. Apparatus according to claim 5, characterized in that _f, the current control devices comprise means for < Q0383 9/1533 201U3A delivering the coolant to the outer surfaces of the first sections of the flexible belt and the casting wheel, which form the first part of the semicircular shape, with a first predetermined volume of flow, and optionally the outer surfaces of the first sections of the flexible belt and the casting wheel and the outer surfaces of the other parts of the flexible belt and to feed the casting wheel, which form the remainder of the semicircular shape, with a second predetermined flow volume. 009839/1533 Le e rs e ι te