CA2314197C - Improvements relating to the pouring of metals - Google Patents
Improvements relating to the pouring of metals Download PDFInfo
- Publication number
- CA2314197C CA2314197C CA 2314197 CA2314197A CA2314197C CA 2314197 C CA2314197 C CA 2314197C CA 2314197 CA2314197 CA 2314197 CA 2314197 A CA2314197 A CA 2314197A CA 2314197 C CA2314197 C CA 2314197C
- Authority
- CA
- Canada
- Prior art keywords
- pouring device
- mould
- launder
- molten metal
- metal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Landscapes
- Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
Abstract
A pouring device for the casting of metals is disclosed. The device includes a discharge assembly for discharging molten metal into a mould, feed means for delivering molten metal to the discharge assembly, measuring means adapted to measure the level of molten metal in the discharge assembly, and valve means provided in operative association with the discharge assembly, the valve means being responsive to signals from the measuring means to control the rate of discharge of molten metal by the discharge assembly.
A continuous method of casting metal is also disclosed.
A continuous method of casting metal is also disclosed.
Description
IMPROVEMENTS RELATING TO THE POURING OF METALS
Field of the Invention This invention relates to a pouring device for metal casting and in a particular non-limiting aspect relates to a pouring device which is suitable for operation with automatic casting apparatus of the type described in Applicant's co-pending Australian patent Application No 69991 /98.
Background of the Invention In typical systems for the casting of molten metals such as zinc or lead, a launder is used to cast the molten metal into a mould. In this casting process it is important to ensure that the amount of metal cast into the mould falls within acceptable weight parameters.
It is also important to ensure that splashing is minimised because of the obvious dangers associated with splashing hot metals. More importantly, air should not be included in the molten metal as it can cause oxidation of the metal with the formation of unwanted dross. Voids in the cast metal resulting from the inclusion of air, also effect the mechanical properties of the metal.
Thus there is a need for a launder design and pouring system device which obviates or minimises the stated difficulties associated with casting metal using a launder.
In Applicant's co-pending Australian patent Application No 69991/98, the disclosures of which are incorporated herein by this cross reference, there is disclosed a launder design which to some extent reduces the launder casting difficulties mentioned above.
However, because the launder requires a tilting action to allow different moulds to be moved under the launder pouring system for the casting process and to cause metal flow, it is not possible to maintain a constant level of molten metal in the launder. This means that molten metal must he caused to flow through the launder at variable rates and depths with the result that smooth metal flow is not possible. Thus, the metal experiences turbulence and the problems associated with turbulence such as mixing with air.
The current invention seeks to improve upon Applicant's earlier launder design by reducing the turbulence normally associated with the tilting action of tilting launder designs.
Field of the Invention This invention relates to a pouring device for metal casting and in a particular non-limiting aspect relates to a pouring device which is suitable for operation with automatic casting apparatus of the type described in Applicant's co-pending Australian patent Application No 69991 /98.
Background of the Invention In typical systems for the casting of molten metals such as zinc or lead, a launder is used to cast the molten metal into a mould. In this casting process it is important to ensure that the amount of metal cast into the mould falls within acceptable weight parameters.
It is also important to ensure that splashing is minimised because of the obvious dangers associated with splashing hot metals. More importantly, air should not be included in the molten metal as it can cause oxidation of the metal with the formation of unwanted dross. Voids in the cast metal resulting from the inclusion of air, also effect the mechanical properties of the metal.
Thus there is a need for a launder design and pouring system device which obviates or minimises the stated difficulties associated with casting metal using a launder.
In Applicant's co-pending Australian patent Application No 69991/98, the disclosures of which are incorporated herein by this cross reference, there is disclosed a launder design which to some extent reduces the launder casting difficulties mentioned above.
However, because the launder requires a tilting action to allow different moulds to be moved under the launder pouring system for the casting process and to cause metal flow, it is not possible to maintain a constant level of molten metal in the launder. This means that molten metal must he caused to flow through the launder at variable rates and depths with the result that smooth metal flow is not possible. Thus, the metal experiences turbulence and the problems associated with turbulence such as mixing with air.
The current invention seeks to improve upon Applicant's earlier launder design by reducing the turbulence normally associated with the tilting action of tilting launder designs.
Disclosure of the Invention In one aspect the invention provides a pouring device for the casting of metals including, a discharge assembly for discharging molten metal into a mould, feed means for delivering molten metal to the discharge assembly, measuring means adapted to measure the level of molten metal in the discharge assembly, and valve means provided in operative association with the discharge assembly, the valve means being responsive to signals from the measuring means to control the rate of discharge of molten metal by the discharge assembly.
The discharge assembly may include a funnel. The funnel may also include an outlet. The outlet may be opened and closed by the valve means. The outlet may be associated with a diffuser for controlling flow of metal.
The feed means may include a launder. The launder may take the form of a channel reservoir. The channel reservoir is suitably arranged to deliver molten metal from a molten metal source to the funnel. It may be associated with a return launder. The return launder is suitably arranged to direct any overflow of molten metal provided by the feed means away from the funnel. Suitably, it may be arranged to return the overflow molten metal to the molten metal source, or it may be integral with the funnel and return the overflow molten metal to the mould. In an alternative embodiment the return launder may be suitably arranged to return the overflow metal to a reject area or vessel.
The return launder may include a return inlet. The return inlet may be arranged so that when molten metal exceeds a predetermined level in the launder, it flows under the influence of gravity via the return launder to the metal source.
A pump may be provided to pump metal from the metal source into the launder.
Suitably the pump may be arranged to pump metal at a constant rate. The pump may in an alternative embodiment be arranged to pump metal at a variable rate.
The valve means may include a member for opening and closing the outlet. It may be a poppet valve.
Suitably the valve means is operated by a powered actuator which may be electrically activated to open and close the valve means. This device may be a linear actuator. The linear actuator may be connected to the valve means by a valve stem. The valve stem may extend into the funnel of the discharge assembly.
Suitably, the powered actuator can act to vary the rate of discharge of metal from the discharge assembly during the period metal is being cast into a mould. For example, the actuator may open the valve means at the start of discharge into a mould to initially cause metal to discharge into the mould at a relatively slow rate. The actuator may then adjust the valve means to flow at a relatively faster rate after a proportion of the metal has been cast into the mould.
The pouring device may include a launder. The launder may be supported so as to allow the weight of the launder pressing down on the support, including the molten metal contained therein to be weighed by the measuring means. Thus the action of the valve may be controlled in response to the weight measured by the measuring means.
Suitably, the launder is supported for pivotal movement. It may also be supported by a structure including a load cell for measuring the weight of the launder.
A measuring means may be provided to directly measure the level of molten metal in the launder. The measuring means may be a laser level sensor, probe or similar device.
Control means may be provided to control the operation of the valve means in response to signals from the measuring means. The control means may operate to provide that the level of molten metal in the launder falls within predetermined limits during continuous operation. The control means may also operate to control the flow rate of the pump.
Alternatively, or in addition, the control means may operate to provide that the level of the molten metal in the mould falls within a predetermined level during continuous operation.
As the launder may be relatively fixed in position it is necessary to bring moulds up towards the level of the discharge assembly of the launder.
Thus, the launder may be associated with supply means for bringing moulds into registry with the discharge assembly of the launder.
The supply means may include a lifting assembly for raising and lowering moulds with respect to the discharge assembly.
Suitably the lifting assembly initially lifts each mould from a lower starting position to a higher one in registry with the discharge assembly. Thereafter each mould may be gradually lowered during the actual filling of the mould with molten metal by the launder.
This is so as to keep the level of the metal in the mould close to the outlet of the discharge assembly during the period metal is cast into the mould. In this way, the risks of splash, turbulence and entrainment of air are reduced. Other benefits may include improvements in accuracy of block weight, less lip on the edge of blocks and less mould damage due to less concentration of incoming hot metal on one point of the mould.
Finally, after the mould has been filled with a predetermined weight of metal, it may be returned to its lower starting position.
The lifting assembly may include mould weighing means for measuring the weight of metal cast into the mould during the casting process. The position of the mould relative to the outlet of the discharge assembly may be adjusted in accordance with the weight measured by the mould weighing means. The control means may operate to control the level of the mould on the lifting assembly in response to signals from the mould weighing means. The control means may also operate to control the valve in response to signals from the mould weighing.
The control means may also operate to control the feed pump in response to signals from the mould weighing means.
The lifting assembly may include a hydraulic cylinder which is actuated by the control means to lower and raise the moulds.
Suitably the supply means includes means for indexing moulds to a position underneath the discharge assembly ready to be lifted into position by the lifting assembly. These indexing means may include a turntable. The turntable may include a plurality of cradles for holding the moulds. The turntable may be provided with access openings beneath the cradles. This is to allow the lifting assembly to protrude therethrough when lifting moulds towards and into registry with the discharge assembly. Most suitably, the turntable will be of a type described in Applicant's co-pending Australian patent Application No 69991/98.
In further aspects the invention provides lifting assemblies, discharge assemblies and/or supply means as hereinbefore described and/or any combination of two or more of these.
In a further aspect the invention provides a continuous method of casting molten metal into a mould including the steps of using a launder having an outlet to supply molten metal, serially indexing moulds to a starting position beneath the outlet, raising each mould to a fill position in registry with the outlet, filling each mould with metal, 5 returning each filled mould to the starting position, and moving each mould away from the starting position while moving a succeeding mould to the starting position.
Most suitably, each mould is gradually lowered during the casting of the molten metal to maintain the outlet within a predetermined distance or range of distances in relation to the level of metal cast into the mould.
Preferred embodiments of the invention will now be described with reference to the accompanying drawings.
Brief Description of the Drawings Figure 1 shows a side elevational view of a pouring device in accordance with the invention associated with a turntable for delivering moulds;
Figure 1 a shows a forward section of the pouring device shown in Figure 1 on an expanded scale;
Figure I b shows the section A-A of the pouring device of Figure la;
Figure 2 shows a plan view of a pouring device in association with fragmentary views of a turntable and molten metal supply;
Figure 2a shows an expanded plan view of a section of Figure 2 showing a portion of the turntable and lifting apparatus for supplying moulds to the pouring device.
Figure 3 shows a side elevation of the block lift and weight control.
Detailed Description of the Preferred Embodiments Referring to Figures 1, la, Ih, 2, 2a and 3 of the accompanying drawings there is shown a pouring device generally designated 1 in association with a turntable 3 and a lifting assembly 4.
The discharge assembly may include a funnel. The funnel may also include an outlet. The outlet may be opened and closed by the valve means. The outlet may be associated with a diffuser for controlling flow of metal.
The feed means may include a launder. The launder may take the form of a channel reservoir. The channel reservoir is suitably arranged to deliver molten metal from a molten metal source to the funnel. It may be associated with a return launder. The return launder is suitably arranged to direct any overflow of molten metal provided by the feed means away from the funnel. Suitably, it may be arranged to return the overflow molten metal to the molten metal source, or it may be integral with the funnel and return the overflow molten metal to the mould. In an alternative embodiment the return launder may be suitably arranged to return the overflow metal to a reject area or vessel.
The return launder may include a return inlet. The return inlet may be arranged so that when molten metal exceeds a predetermined level in the launder, it flows under the influence of gravity via the return launder to the metal source.
A pump may be provided to pump metal from the metal source into the launder.
Suitably the pump may be arranged to pump metal at a constant rate. The pump may in an alternative embodiment be arranged to pump metal at a variable rate.
The valve means may include a member for opening and closing the outlet. It may be a poppet valve.
Suitably the valve means is operated by a powered actuator which may be electrically activated to open and close the valve means. This device may be a linear actuator. The linear actuator may be connected to the valve means by a valve stem. The valve stem may extend into the funnel of the discharge assembly.
Suitably, the powered actuator can act to vary the rate of discharge of metal from the discharge assembly during the period metal is being cast into a mould. For example, the actuator may open the valve means at the start of discharge into a mould to initially cause metal to discharge into the mould at a relatively slow rate. The actuator may then adjust the valve means to flow at a relatively faster rate after a proportion of the metal has been cast into the mould.
The pouring device may include a launder. The launder may be supported so as to allow the weight of the launder pressing down on the support, including the molten metal contained therein to be weighed by the measuring means. Thus the action of the valve may be controlled in response to the weight measured by the measuring means.
Suitably, the launder is supported for pivotal movement. It may also be supported by a structure including a load cell for measuring the weight of the launder.
A measuring means may be provided to directly measure the level of molten metal in the launder. The measuring means may be a laser level sensor, probe or similar device.
Control means may be provided to control the operation of the valve means in response to signals from the measuring means. The control means may operate to provide that the level of molten metal in the launder falls within predetermined limits during continuous operation. The control means may also operate to control the flow rate of the pump.
Alternatively, or in addition, the control means may operate to provide that the level of the molten metal in the mould falls within a predetermined level during continuous operation.
As the launder may be relatively fixed in position it is necessary to bring moulds up towards the level of the discharge assembly of the launder.
Thus, the launder may be associated with supply means for bringing moulds into registry with the discharge assembly of the launder.
The supply means may include a lifting assembly for raising and lowering moulds with respect to the discharge assembly.
Suitably the lifting assembly initially lifts each mould from a lower starting position to a higher one in registry with the discharge assembly. Thereafter each mould may be gradually lowered during the actual filling of the mould with molten metal by the launder.
This is so as to keep the level of the metal in the mould close to the outlet of the discharge assembly during the period metal is cast into the mould. In this way, the risks of splash, turbulence and entrainment of air are reduced. Other benefits may include improvements in accuracy of block weight, less lip on the edge of blocks and less mould damage due to less concentration of incoming hot metal on one point of the mould.
Finally, after the mould has been filled with a predetermined weight of metal, it may be returned to its lower starting position.
The lifting assembly may include mould weighing means for measuring the weight of metal cast into the mould during the casting process. The position of the mould relative to the outlet of the discharge assembly may be adjusted in accordance with the weight measured by the mould weighing means. The control means may operate to control the level of the mould on the lifting assembly in response to signals from the mould weighing means. The control means may also operate to control the valve in response to signals from the mould weighing.
The control means may also operate to control the feed pump in response to signals from the mould weighing means.
The lifting assembly may include a hydraulic cylinder which is actuated by the control means to lower and raise the moulds.
Suitably the supply means includes means for indexing moulds to a position underneath the discharge assembly ready to be lifted into position by the lifting assembly. These indexing means may include a turntable. The turntable may include a plurality of cradles for holding the moulds. The turntable may be provided with access openings beneath the cradles. This is to allow the lifting assembly to protrude therethrough when lifting moulds towards and into registry with the discharge assembly. Most suitably, the turntable will be of a type described in Applicant's co-pending Australian patent Application No 69991/98.
In further aspects the invention provides lifting assemblies, discharge assemblies and/or supply means as hereinbefore described and/or any combination of two or more of these.
In a further aspect the invention provides a continuous method of casting molten metal into a mould including the steps of using a launder having an outlet to supply molten metal, serially indexing moulds to a starting position beneath the outlet, raising each mould to a fill position in registry with the outlet, filling each mould with metal, 5 returning each filled mould to the starting position, and moving each mould away from the starting position while moving a succeeding mould to the starting position.
Most suitably, each mould is gradually lowered during the casting of the molten metal to maintain the outlet within a predetermined distance or range of distances in relation to the level of metal cast into the mould.
Preferred embodiments of the invention will now be described with reference to the accompanying drawings.
Brief Description of the Drawings Figure 1 shows a side elevational view of a pouring device in accordance with the invention associated with a turntable for delivering moulds;
Figure 1 a shows a forward section of the pouring device shown in Figure 1 on an expanded scale;
Figure I b shows the section A-A of the pouring device of Figure la;
Figure 2 shows a plan view of a pouring device in association with fragmentary views of a turntable and molten metal supply;
Figure 2a shows an expanded plan view of a section of Figure 2 showing a portion of the turntable and lifting apparatus for supplying moulds to the pouring device.
Figure 3 shows a side elevation of the block lift and weight control.
Detailed Description of the Preferred Embodiments Referring to Figures 1, la, Ih, 2, 2a and 3 of the accompanying drawings there is shown a pouring device generally designated 1 in association with a turntable 3 and a lifting assembly 4.
The arrangement of pouring device, turntable and lifting assembly is for the purposes of casting molten metal obtained from the molten metal source 19 into the moulds 5. These moulds are provided with mould pins 6 as per the description in Australian patent Application No 69991 /98.
The pouring device includes feed means 7, in the form of a channel reservoir or launder.
This is arranged to feed molten metal from the source 19 to the discharge assembly 9.
A return launder 11 is arranged to allow excess molten metal to flow under the influence of gravity back to the source 19.
The return launder includes the overflow return channel 12 communicating with the overflow from the channel reservoir via the return inlet 47.
A pump 13 is arranged to pump molten metal from the source 19 into the channel reservoir and to maintain the level of metal therein within predetermined limits. This level of metal is represented by the dotted lines 29 for the highest level and 31 for the lowest level.
The launder is mounted on the post 21 via a pivot mount 23 near one end of the launder.
Near the other end of the launder a second post 25 provided with a load cell 27 provides support for the launder. Should some means other than a load cell be used to measure the level in the launder, then this pivot would not be required. Suitably, a laser sensor 75 may be arranged to determine the level of metal in the launder.
It should be noted that the pivot mount 23 is only necessary for allowing very slight pivotal movements required to allow the load cell 27 to give weight readings for the combined weight of the launder and molten metal contained therein. The combined weight corresponds to the level of molten metal in the launder.
The discharge assembly 9 includes a funnel 33 provided at the end of the V-shaped launder. The funnel is positioned so that it can deliver molten metal into the mould 5 which has been located underneath the outlet 35 of the funnel by the turntable 3.
The outlet of the funnel is formed of a material which is capable of withstanding the harsh environment associated with the casting of molten metal.
The outlet may be provided with a diffuser which is not shown in the drawing, for the purposes of smoothing the flow of molten metal from the outlet into the mould, reducing splashing and reducing the degree of entrainment of air.
The pouring device includes feed means 7, in the form of a channel reservoir or launder.
This is arranged to feed molten metal from the source 19 to the discharge assembly 9.
A return launder 11 is arranged to allow excess molten metal to flow under the influence of gravity back to the source 19.
The return launder includes the overflow return channel 12 communicating with the overflow from the channel reservoir via the return inlet 47.
A pump 13 is arranged to pump molten metal from the source 19 into the channel reservoir and to maintain the level of metal therein within predetermined limits. This level of metal is represented by the dotted lines 29 for the highest level and 31 for the lowest level.
The launder is mounted on the post 21 via a pivot mount 23 near one end of the launder.
Near the other end of the launder a second post 25 provided with a load cell 27 provides support for the launder. Should some means other than a load cell be used to measure the level in the launder, then this pivot would not be required. Suitably, a laser sensor 75 may be arranged to determine the level of metal in the launder.
It should be noted that the pivot mount 23 is only necessary for allowing very slight pivotal movements required to allow the load cell 27 to give weight readings for the combined weight of the launder and molten metal contained therein. The combined weight corresponds to the level of molten metal in the launder.
The discharge assembly 9 includes a funnel 33 provided at the end of the V-shaped launder. The funnel is positioned so that it can deliver molten metal into the mould 5 which has been located underneath the outlet 35 of the funnel by the turntable 3.
The outlet of the funnel is formed of a material which is capable of withstanding the harsh environment associated with the casting of molten metal.
The outlet may be provided with a diffuser which is not shown in the drawing, for the purposes of smoothing the flow of molten metal from the outlet into the mould, reducing splashing and reducing the degree of entrainment of air.
A valve 37 provided in the funnel is used to regulate the flow of molten metal from the discharge assembly. The valve includes a ball 39 which may be formed of the same material as the outlet 35.
A valve stem 41 connects the ball to an electrically operated actuation mechanism in the form of the linear actuator 43. The linear actuator is controllable by control means not shown in the drawings to control the extent of opening the valve. The control means may be a computer or other electronic device such as a PLC.
The turntable 3 is constructed to rotate about the turntable axis 49. It includes a plurality of mould cradles 51 which are each adapted to be rotated to a starting position under the outlet of the discharge assembly.
Axis openings 53 are provided under each of the mould cradles. These are for the purpose of allowing the lifting assembly to push through the relevant openings to lift the mould from the starting position in which it is shown resting on the cradle in Figure 1, to the elevated position also shown in Figure 1. In the elevated position the discharge assembly actually protrudes into the mould in the casting process.
The lifting assembly shown in more detail in Figure 3 and Figure 2a includes a base plate 55 secured to a floor 57. A cavity 59 is provided beneath the base plate to accommodate the rear portion of the lifting assembly.
The lifting assembly is constructed so that the mould support 61 comes into registry with the bottom portion of a mould when the turntable indexes the mould to a position below the outlet.
The mould support is itself mounted on slidable supports 62 which are adapted to slide up and down in the hollow guides 68.
A hydraulic cylinder 63 is arranged to move the mould support up and down.
The hydraulic cylinder is mounted on the cylinder mounting assembly 65. This includes the vertical mounting pieces 66 and cylinder mounting plate 67.
The cylinder mounting plate in turn is mounted on the hollow guides 68 which are themselves secured to the assembly mounting plate 69. The assembly mounting plate is mounted via bolts 70 to the base plate 55. Thus the entire lifting assembly 4 may be easily removed by unscrewing the bolts and lifting the assembly mounting plate.
g Three load cells 71 shown in Figure 2a are provided underneath the mould support 61 for the purposes of sensing the weight of molten metal cast into the mould on a continuous basis. The output from the load cells is connected to control means which control the operation of the lifting assembly and the valve.
Finally, a splash cover 73 is provided to protect the lifting assembly against molten metal which may be splashed from the moulds.
In operation of the apparatus, moulds 5 on the turntable 3 are each indexed into a starting position above the lifting assembly 4 and below the discharge assembly 9, as the lifting assembly is provided immediately underneath the discharge assembly.
Electronic control means actuate the hydraulic cylinder 63 to push the mould support 61 through the access opening 53 to contact the underneath central portion of the mould and push it to the upward position shown in Figure 1 of the drawings.
Once it has reached this upward position, the valve 37 partially opens in response to signals from the control means and metal which has been maintained in the launder between the levels 29 and 31 starts to flow at a relatively low rate into the mould until the bottom of the mould 4 has been covered with molten metal. This initial low rate is to limit the amount of splashing and air entrainment in the initial stages of filling the mould.
At the same time, the load cells 71 are sensing the amount of metal in the mould. Signals from the load cells are directed to the controller which then actuates the cylinder to lower the mould as it is filling with metal and to increase the degree of opening of the valve to increase the rate of metal flowing from the launder into the mould. The signals from the load cell 27 which indicate the level of the molten metal in the launder are also fed into the controller at the same time. These signals may also be factored into adjusting the extent by which the control means open or close the valve to ensure that the level of molten metal in the launder stays within the defined predetermined limits. For example, if the metal level in the launder is low, the valve may limit the flow rate. Alternatively, if it is high, the flow rate may be increased although the main guard against overly high metal levels is the return launder.
The control means may also serve to control the degree of pumping of the pump 13 in certain arrangements.
During the mould filling operation the level of the outlet 35 is kept within a predetermined distance range of the level of metal in the mould to reduce splashing.
Initially it is above the metal which then rises to cover the outlet as the mould is filled. Once the mould has been filled however, the control means actuates the cylinder to return the filled mould to the cradle and actuates the turntable to index the next mould on the turntable for repeating the filling cycle.
The provision of the return launder 11 ensures that excess molten metal will be returned to the molten metal source 19 as the level of the return inlet 47 is below that of the predetermined upper level of metal 29 shown in the drawing. The greater the level of metal above the return inlet 47 the greater the rate at which the excess metal flows back under the influence of gravity through the return launder to the metal source.
Thus, the system is automatically self regulating.
The return launder may be constructed to return excess metal directly to the mould in certain arrangements.
These arrangements would serve to provide a means of overflow should returning metal to the source be impracticable.
It can be seen from the foregoing description that the level of molten metal in the launder is maintained within fairly tightly defined limits. Furthermore, the rate of metal discharged through the discharge assembly is also carefully controlled as is the height of the discharge assembly with respect to the level of metal in the mould. All of these factors contribute to reducing splashing and the amount of turbulence in the molten metal as it passes through the launder and through the discharge assembly into the mould with the result that the likelihood of air entrainment and formation of dross is reduced.
While it has been convenient to describe the invention herein in relation to particularly preferred embodiments, it is to be appreciated that other constructions and arrangements are considered as falling within the scope of the invention. Various modifications, alterations, variations and/or additions to the constructions and arrangements described herein are also considered as falling within the scope and ambit of the present invention.
Integer List 1 pouring device 3 turntable 5 4 lifting assembly 5 mould 6 mould pins 7 feed means (launder-channel reservoir) 9 discharge assembly 10 11 return launder 12 overflow return 13 pump 19 molten metal source 21 post 23 pivot mount post 27 load cell 29, range of metal levels 33 funnel 20 35 outlet (with optional diffuser - not shown) 37 valve 39 ball 41 valve stem 43 linear actuator 25 47 return inlet 49 turntable axis 51 mould cradle 53 access opening 55 base plate 57 floor 59 cavity 61 mould support 62 slidable supports 63 hydraulic cylinder 65 cylinder mounting assembly 66 vertical mounting pieces 67 cylinder mounting plate 68 hollow guides 69 assembly mounting plate 70 bolts 71 load cells 73 splash cover 75 direct level measurement means (laser sensor)
A valve stem 41 connects the ball to an electrically operated actuation mechanism in the form of the linear actuator 43. The linear actuator is controllable by control means not shown in the drawings to control the extent of opening the valve. The control means may be a computer or other electronic device such as a PLC.
The turntable 3 is constructed to rotate about the turntable axis 49. It includes a plurality of mould cradles 51 which are each adapted to be rotated to a starting position under the outlet of the discharge assembly.
Axis openings 53 are provided under each of the mould cradles. These are for the purpose of allowing the lifting assembly to push through the relevant openings to lift the mould from the starting position in which it is shown resting on the cradle in Figure 1, to the elevated position also shown in Figure 1. In the elevated position the discharge assembly actually protrudes into the mould in the casting process.
The lifting assembly shown in more detail in Figure 3 and Figure 2a includes a base plate 55 secured to a floor 57. A cavity 59 is provided beneath the base plate to accommodate the rear portion of the lifting assembly.
The lifting assembly is constructed so that the mould support 61 comes into registry with the bottom portion of a mould when the turntable indexes the mould to a position below the outlet.
The mould support is itself mounted on slidable supports 62 which are adapted to slide up and down in the hollow guides 68.
A hydraulic cylinder 63 is arranged to move the mould support up and down.
The hydraulic cylinder is mounted on the cylinder mounting assembly 65. This includes the vertical mounting pieces 66 and cylinder mounting plate 67.
The cylinder mounting plate in turn is mounted on the hollow guides 68 which are themselves secured to the assembly mounting plate 69. The assembly mounting plate is mounted via bolts 70 to the base plate 55. Thus the entire lifting assembly 4 may be easily removed by unscrewing the bolts and lifting the assembly mounting plate.
g Three load cells 71 shown in Figure 2a are provided underneath the mould support 61 for the purposes of sensing the weight of molten metal cast into the mould on a continuous basis. The output from the load cells is connected to control means which control the operation of the lifting assembly and the valve.
Finally, a splash cover 73 is provided to protect the lifting assembly against molten metal which may be splashed from the moulds.
In operation of the apparatus, moulds 5 on the turntable 3 are each indexed into a starting position above the lifting assembly 4 and below the discharge assembly 9, as the lifting assembly is provided immediately underneath the discharge assembly.
Electronic control means actuate the hydraulic cylinder 63 to push the mould support 61 through the access opening 53 to contact the underneath central portion of the mould and push it to the upward position shown in Figure 1 of the drawings.
Once it has reached this upward position, the valve 37 partially opens in response to signals from the control means and metal which has been maintained in the launder between the levels 29 and 31 starts to flow at a relatively low rate into the mould until the bottom of the mould 4 has been covered with molten metal. This initial low rate is to limit the amount of splashing and air entrainment in the initial stages of filling the mould.
At the same time, the load cells 71 are sensing the amount of metal in the mould. Signals from the load cells are directed to the controller which then actuates the cylinder to lower the mould as it is filling with metal and to increase the degree of opening of the valve to increase the rate of metal flowing from the launder into the mould. The signals from the load cell 27 which indicate the level of the molten metal in the launder are also fed into the controller at the same time. These signals may also be factored into adjusting the extent by which the control means open or close the valve to ensure that the level of molten metal in the launder stays within the defined predetermined limits. For example, if the metal level in the launder is low, the valve may limit the flow rate. Alternatively, if it is high, the flow rate may be increased although the main guard against overly high metal levels is the return launder.
The control means may also serve to control the degree of pumping of the pump 13 in certain arrangements.
During the mould filling operation the level of the outlet 35 is kept within a predetermined distance range of the level of metal in the mould to reduce splashing.
Initially it is above the metal which then rises to cover the outlet as the mould is filled. Once the mould has been filled however, the control means actuates the cylinder to return the filled mould to the cradle and actuates the turntable to index the next mould on the turntable for repeating the filling cycle.
The provision of the return launder 11 ensures that excess molten metal will be returned to the molten metal source 19 as the level of the return inlet 47 is below that of the predetermined upper level of metal 29 shown in the drawing. The greater the level of metal above the return inlet 47 the greater the rate at which the excess metal flows back under the influence of gravity through the return launder to the metal source.
Thus, the system is automatically self regulating.
The return launder may be constructed to return excess metal directly to the mould in certain arrangements.
These arrangements would serve to provide a means of overflow should returning metal to the source be impracticable.
It can be seen from the foregoing description that the level of molten metal in the launder is maintained within fairly tightly defined limits. Furthermore, the rate of metal discharged through the discharge assembly is also carefully controlled as is the height of the discharge assembly with respect to the level of metal in the mould. All of these factors contribute to reducing splashing and the amount of turbulence in the molten metal as it passes through the launder and through the discharge assembly into the mould with the result that the likelihood of air entrainment and formation of dross is reduced.
While it has been convenient to describe the invention herein in relation to particularly preferred embodiments, it is to be appreciated that other constructions and arrangements are considered as falling within the scope of the invention. Various modifications, alterations, variations and/or additions to the constructions and arrangements described herein are also considered as falling within the scope and ambit of the present invention.
Integer List 1 pouring device 3 turntable 5 4 lifting assembly 5 mould 6 mould pins 7 feed means (launder-channel reservoir) 9 discharge assembly 10 11 return launder 12 overflow return 13 pump 19 molten metal source 21 post 23 pivot mount post 27 load cell 29, range of metal levels 33 funnel 20 35 outlet (with optional diffuser - not shown) 37 valve 39 ball 41 valve stem 43 linear actuator 25 47 return inlet 49 turntable axis 51 mould cradle 53 access opening 55 base plate 57 floor 59 cavity 61 mould support 62 slidable supports 63 hydraulic cylinder 65 cylinder mounting assembly 66 vertical mounting pieces 67 cylinder mounting plate 68 hollow guides 69 assembly mounting plate 70 bolts 71 load cells 73 splash cover 75 direct level measurement means (laser sensor)
Claims (39)
1. A pouring device for the casting of metals including:
(a) a discharge assembly for discharging molten metal into a mould;
(b) feed means for delivering molten metal to the discharge assembly from a molten metal source;
(c) measuring means adapted to measure the level of molten metal in the discharge assembly; and (d) valve means provided in operative association with the discharge assembly, the valve means being responsive to signals from the measuring means to control the rate of discharge of molten metal by the discharge assembly.
(a) a discharge assembly for discharging molten metal into a mould;
(b) feed means for delivering molten metal to the discharge assembly from a molten metal source;
(c) measuring means adapted to measure the level of molten metal in the discharge assembly; and (d) valve means provided in operative association with the discharge assembly, the valve means being responsive to signals from the measuring means to control the rate of discharge of molten metal by the discharge assembly.
2. A pouring device according to claim 1, wherein the discharge assembly includes a funnel.
3. A pouring device according to claim 2, wherein the funnel includes an outlet which may be opened and closed by the valve means.
4. A pouring device according to claim 3, wherein the outlet is associated with a diffuser for controlling flow of metal.
5. A pouring device according to any one of claims 2 to 4, wherein the feed means includes at least one launder arranged to deliver molten metal from a molten metal source to the funnel.
6. A pouring device according to claim 5, wherein the launder is supported so as to allow the weight of the launder pressing down on the support, including the molten metal contained therein, to be weighed by the measuring means.
7. A pouring device according to claim 5 or 6, wherein the or each launder is supported for pivotal movement.
8. A pouring device according to claim 6 or 7, wherein the launder is supported by a structure including a load cell for measuring the weight of the launder.
9. A pouring device according to claim 5, wherein a measuring means is provided to measure the level of molten metal in the launder.
10. A pouring device according to claim 9, wherein said measuring means is a laser sensor or a probe.
11. A pouring device according to any one of claims 2 to 10, and further including a return launder arranged to direct any overflow of molten metal provided by the feed means away from the funnel.
12. A pouring device according to claim 11, wherein the return launder is arranged to return the overflow molten metal to the molten metal source.
13. A pouring device according to claim 11, wherein the return launder is formed integrally with the funnel to return overflow molten metal to the mould.
14. A pouring device according to claim 11, wherein the return launder is arranged to return overflow material to a reject area or vessel.
15. A pouring device according to any one of claims 11 to 14, wherein the return launder includes a return inlet arranged so that when molten metal exceeds a predetermined level in the launder, it flows under the influence of gravity via the return launder to the metal source.
16. A pouring device according to any one of claims 5 to 15, and further including a feed pump to pump metal from the metal source into the launder.
17. A pouring device according to claim 16, wherein the feed pump is arranged to pump metal at a constant rate.
18. A pouring device according to claim 14, wherein the pump is arranged to pump metal at a variable rate.
19. A pouring device according to any one of claims 1 to 18, wherein the valve means is operated by a powered actuator to open and close the valve means.
20. A pouring device according to claim 19, wherein the powered actuator is a linear actuator connected to the valve means by a valve stem.
21. A pouring device according to claim 20, wherein the valve stem extends into the funnel of the discharge assembly.
22. A pouring device according to any one of claims 1 to 21, wherein a control means is provided to control the operation of the valve means in response to signals from the measuring means.
23. A pouring device according to claim 22, wherein the control means operates to provide that the level of molten metal in the launder falls within predetermined limits during a continuous operation.
24. A pouring device according to claim 22, wherein the control means operates to provide that the level of molten metal in the mould falls within a predetermined limits during a continuous operation.
25. A pouring device according to any one of claims 22 to 24, wherein the control means also operates to control the flow rate of the feed pump in response to signals from measuring means.
26. A pouring device according to any one of claims 5 to 25, wherein said feed launder is associated with supply means for bringing moulds into registry with the discharge assembly.
27. A pouring device according to claim 26, wherein the supply means includes a lifting assembly for raising and lowering moulds with respect to the discharge assembly.
28. A pouring device according to claim 27, wherein said lifting assembly initially lifts each mould from a lower starting position to a higher one in registry with the discharge assembly.
29. A pouring device according to claim 27 or 28, wherein the lifting assembly lowers the moulds during filling of the moulds with molten metal.
30. A pouring device according to any one of claims 27 to 29, wherein the lifting assembly returns the filled mould to an initial lower starting position.
31. A pouring device according to any one of claims 27 to 30, wherein the lifting assembly includes a mould weighing means for measuring the weight of metal cast into the mould during the casting process.
32. A pouring device according to claim 31, wherein the control means controls the level of the mould on the lifting assembly in response to signals from the mould weighing means.
33. A pouring device according to claim 31 or 32, wherein the control means controls the feed pump in response to signals from the mould weighing means.
34. A pouring device according to any one of claims 27 to 33, wherein the supply means further includes means for indexing moulds to a position underneath the discharge assembly ready to be lifted into position by the lifting assembly.
35. A pouring device according to claim 34, wherein the indexing means includes a turntable.
36. A pouring device according to claim 35, wherein the turntable includes a plurality of cradles for holding the moulds.
37. A pouring device according to claim 36, wherein the turntable includes access openings beneath the cradles to allow the lifting assembly to protrude therethrough when lifting moulds towards and into registry with the discharge assembly.
38. A continuous method of casting molten metal into a mould including the steps of:
(a) using a launder having an outlet to supply molten metal;
(b) serially indexing moulds to a starting position beneath the outlet;
(c) raising each mould to a fill position in registry with the outlet;
(d) filling each mould with metal;
(e) returning each filled mould to the starting position; and (f) moving each mould away from the starting position while moving a succeeding mould to the starting position.
(a) using a launder having an outlet to supply molten metal;
(b) serially indexing moulds to a starting position beneath the outlet;
(c) raising each mould to a fill position in registry with the outlet;
(d) filling each mould with metal;
(e) returning each filled mould to the starting position; and (f) moving each mould away from the starting position while moving a succeeding mould to the starting position.
39. A method according to claim 38, wherein each mould is lowered during the casting of the molten metal to maintain the outlet within a predetermined distance or range of distances in relation to the level of metal cast into the mould.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AUPQ8574A AUPQ857400A0 (en) | 2000-07-05 | 2000-07-05 | Improvements relating to the pouring of metals |
| AUPQ8574 | 2000-07-05 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2314197A1 CA2314197A1 (en) | 2002-01-05 |
| CA2314197C true CA2314197C (en) | 2010-08-17 |
Family
ID=3822640
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2314197 Expired - Lifetime CA2314197C (en) | 2000-07-05 | 2000-07-21 | Improvements relating to the pouring of metals |
Country Status (2)
| Country | Link |
|---|---|
| AU (1) | AUPQ857400A0 (en) |
| CA (1) | CA2314197C (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102441666B (en) * | 2011-12-09 | 2013-07-10 | 西南铝业（集团）有限责任公司 | Method and system for controlling emergency rise of casting runner |
-
2000
- 2000-07-05 AU AUPQ8574A patent/AUPQ857400A0/en not_active Withdrawn
- 2000-07-21 CA CA 2314197 patent/CA2314197C/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| CA2314197A1 (en) | 2002-01-05 |
| AUPQ857400A0 (en) | 2000-07-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2415540B1 (en) | Automatic pouring method | |
| US4114675A (en) | Method and apparatus for pouring a mold with a selectable amount of casting material | |
| US4460163A (en) | Device and furnace for discharging measured quantities of molten metal | |
| CA2314197C (en) | Improvements relating to the pouring of metals | |
| JPH08294765A (en) | Constant molten metal surface level melt holding furnace | |
| US6896032B1 (en) | Stopper-poured molten metal casting vessel with constant head height | |
| JP2009255133A (en) | Differential pressure casting apparatus | |
| JP2000107851A (en) | Apparatus for low-pressure-casting molten metal in up- grade | |
| US6892791B1 (en) | Trajectory compensation for tiltable stopper-poured molten metal casting vessel | |
| CN104907548A (en) | Powerful casting liquid adding system for aluminum alloy wheels | |
| EP0327485B1 (en) | Improvements in liquid metal distribution systems in billet moulds | |
| KR101021029B1 (en) | Low pressure casting device and filling method of inert gas | |
| KR102180806B1 (en) | Snout Device, and Apparatus for Galvanizing Steel Sheet Having The Same | |
| US5080327A (en) | Area displacement device for molten metal ladle | |
| JPH0257463B2 (en) | ||
| JPH0195856A (en) | Pump for supplying molten metal | |
| JP2588142Y2 (en) | Bulk specific gravity measuring device | |
| JPH05293633A (en) | Automatic molten metal pouring apparatus | |
| JP3527628B2 (en) | Hot water supply control device | |
| JPS6138758Y2 (en) | ||
| RU2750227C1 (en) | Continuous metal casting installation | |
| US5645792A (en) | Slag control shape release apparatus for molten metal vessels | |
| SU1154344A1 (en) | Method of controlling process of degassing of molten steel in stream | |
| KR200170170Y1 (en) | Water Supply Device for Tofu Maker | |
| JPS58110169A (en) | Charging method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKEX | Expiry |
Effective date: 20200721 |