JPH01142016A - Continuous vacuum degassing equipment for molten copper - Google Patents

Abstract

PURPOSE:To save the power consumption of continuous vacuum degassing apparatus for molten steel at low cost by raising the molten copper from a molten copper receiving chamber into a connecting chamber continuously vacuum exhausted while blowing inert gas and lowering to a molten steel discharging chamber after adding additive. CONSTITUTION:Upper end parts of a riser tube 8 and a downtake tube 9 inserted into the molten copper receiving chamber 2 and the molten steel discharging chamber 3 in the furnace body 1, respectively, are connected with the connecting chamber 10 and the inner part thereof is made to vacuum with the vacuum exhaust device 15 connecting with an exhaust hole 14. In the above continuous vacuum degassing apparatus 21, the molten copper continuously supplied into the receiving chamber 2 from a molten copper inlet 4 is raised into the riser tube 8 and flowed in the connecting chamber 8 together with inert gas introduced from a blowing hole 11 at the intermediate position. At there, the degassing of the molten copper is executed and also the necessary additive is mixed from an additive charging hole 16. After that, the degassed molten copper is descended to the discharging chamber 3 through the downtake tube 9 and introduced out from a molten steel outlet 6. The inner diameter of the above downtake tube 9 is desirable to be more than 1.5 times the inside diameter of the riser tube 8. Further, the molten copper is desirably stirred by arranging an electromagnetic coil to each of the riser tube 8, downtake tube 9 and the connecting chamber 10.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an apparatus for continuously degassing and refining molten copper under vacuum.

, (Prior Art) Conventionally, vacuum degassing has not been normally performed on molten copper, but recently, the adoption of vacuum degassing is being considered due to the demand for improving the quality of oxygen-free copper. Common vacuum degassing methods include the ladle degassing method, DH degassing method, and RH degassing method, which have been conventionally applied to molten copper.

(Problems to be Solved by the Invention) However, the above-mentioned conventional vacuum degassing methods are all batch processing methods using steel strips. For this reason, it takes a great deal of effort and time to transport the molten metal, such as tapping the ladle into the ladle, transporting the ladle with a crane etc., attaching it to a degassing device, and removing and transporting the ladle after degassing. The temperature drop is also large. In addition, the first few minutes of the vacuum processing time are spent lowering the vacuum chamber to a certain degree of vacuum, so the net vacuum degassing time during one charge operation time becomes even shorter, which increases productivity. In addition, since it is a batch process, large-capacity steel plates, cranes, ladle carts, vacuum tanks, vacuum pumps, etc. are all required, and the equipment costs are low.This invention solves the above-mentioned drawbacks of the conventional method. Well, it's 1.6 years old, 1 year old, 1 year old.

The present invention aims to provide a continuous vacuum degassing device for molten copper.

(Means for Solving the Problems) However, the device of the first invention according to the present invention comprises a furnace body having a receiving chamber communicating with the molten metal inlet and a tapping chamber communicating with the ejection port, and a lower end portion. has a rising pipe inserted into the hot water receiving chamber, a descending pipe whose lower end is inserted into the hot water tapping chamber, and a connecting chamber connecting the lower end of the rising pipe and the upper end of the descending pipe, An additive inlet and an exhaust outlet are provided in the connection chamber,
This continuous vacuum degassing apparatus for molten copper is characterized in that this exhaust port is connected to a vacuum evacuation device, and an inert gas blowing port is provided in the middle part of the riser pipe.

Further, the apparatus of the second invention includes a furnace body including a receiving chamber communicating with a molten metal inlet and a tapping chamber communicating with a molten metal outlet, a riser pipe having a lower end inserted into the receiving chamber, and a rising pipe having a lower end inserted into the receiving chamber. A downcomer pipe inserted into the tapping chamber and a connection chamber connecting the upper end of the riser pipe and the upper end of the downcomer pipe are provided, and the connection chamber is provided with an additive inlet and an exhaust port, and the connection chamber is provided with an additive inlet and an exhaust port. A gate-connected vacuum degassing device for molten copper, characterized in that an inlet is connected to a vacuum evacuation device, and an inert gas inlet and an electromagnetic coil for driving the molten metal are provided in the middle of the riser pipe. .

Further, the apparatus of the third invention includes a furnace body having a storage chamber communicating with a molten metal inlet and a molten metal outlet, a riser pipe whose lower end is inserted into the storage chamber, and a riser pipe whose lower end is inserted into the storage chamber. A downcomer pipe is provided, and a connection chamber that connects the F end of the riser pipe and the upper end of the downcomer pipe, an additive inlet and an exhaust port are provided in the connection chamber, and the exhaust port is connected to a vacuum evacuation device. This continuous vacuum degassing apparatus for molten copper is characterized in that an inert gas inlet is provided in the intermediate portion of the riser pipe.

Further, the apparatus of the fourth invention includes a furnace body having a storage chamber communicating with a molten metal inlet and a molten metal outlet, a rising pipe having a lower end inserted into the storage chamber, and a descending pipe having a lower end inserted into the storage chamber. a connecting chamber that connects the upper end of the rising pipe and the upper end of the descending pipe, the connecting chamber is provided with an additive inlet and an exhaust port, and the exhaust port is connected to a vacuum evacuation device. The continuous vacuum degassing apparatus for molten copper is also characterized in that an inert gas inlet and an electromagnetic coil for driving the molten metal are provided in the middle part of the riser pipe.

(Function) In the continuous vacuum degassing device of this invention, the hot water receiving chamber (
When molten copper is supplied to the first and second inventions) or the storage chamber (third and fourth inventions), the molten copper is sucked up into the connection chamber through the riser pipe by the exhaust action of the connection chamber by the vacuum exhaust device. , and - inert gas blown from an inert gas suction port provided in the middle of the riser pipe (first and third inventions) or the inert gas and electromagnetic coil (second and fourth inventions) The molten copper in the tube is driven upward and continuously supplied into the evacuated connection chamber, and is vacuum degassed as it flows through the connection chamber toward the downcomer. On this occasion,
Since the molten copper is actively stirred by the inert gas for driving the molten metal and adjusting the flow rate, vacuum degassing within the connection chamber is particularly effective. Also the second and fourth
In the invention, the electromagnetic coil also performs induction heating of the molten copper in the riser pipe, so the temperature drop of the molten copper is small. On the other hand, additives for alloys such as aluminum are supplied into the connection chamber from the additive inlet, and the composition of the molten copper is adjusted by effectively utilizing the stirring action. Incidentally, refining flux can also be supplied from the additive inlet. In the first and second inventions, the molten copper after vacuum degassing flows into the tapping chamber through the downcomer pipe, and is continuously supplied to subsequent casting equipment, refining equipment, etc.

Further, in the third and fourth inventions, a part of the molten copper that has flowed into the storage chamber through the downcomer pipe is continuously supplied from the melting outlet to the subsequent equipment together with the molten copper in the storage chamber, and the molten copper in the storage chamber is Together with this, it is sucked into the riser tube and subjected to vacuum degassing treatment again.

(Example) An embodiment of the first invention will be described below with reference to FIG.

In the figure, reference numeral 1 denotes a furnace body made of refractory material, and inside thereof a molten metal receiving chamber 2 and a molten metal tapping chamber 3 are provided at intervals. 4
is a molten metal inlet communicating with the molten metal receiving chamber 2, and is connected to a molten copper supply source such as a melting furnace via a molten metal supply pipe 5. Further, 6 is a molten metal outlet communicating with the tapping chamber 3, and is connected to a subsequent refining tank via a tapping pipe 7. Further, 8 is an ascending pipe, 9 is a descending pipe, and 10 is a connecting chamber, all of which are made of a tubular body made of refractory material such as graphite. The parts are respectively inserted into the hot water tap chamber 3. Reference numeral 11 denotes an inert gas inlet made of a porous brick or the like provided in the middle of the riser pipe 8, and is connected to an inert gas supply source 12 such as argon. Further, 13 is an electromagnetic coil for stirring the molten metal surrounding the middle part of the downcomer pipe 9. The connecting chamber 10 is a tubular body with both ends closed, and the inside of the connecting chamber 10 communicates with the insides of the ascending pipe 8 and the descending pipe 9.

14 is an exhaust port provided in the connection chamber 10, and the steam knee 9
= Connected to a vacuum evacuation device 15 such as Zecta.

Reference numeral 16 denotes an additive inlet provided in the connection chamber 10, and a hopper 17 which accommodates an additive S for alloys such as aluminum.
17. Note that these hoppers have a known structure that allows the inside of the hopper to be evacuated when charging, and 18 is a rotary valve, and 19 is a vacuum pump. Further, 20 is an electromagnetic coil that surrounds the middle part of the connecting chamber 10.
This is to control the amount of movement of the molten metal within 0. Note that 26 is an outer wall (described later) that is attached as necessary.

To degas molten copper using the continuous vacuum descaling device 21 configured as described above, molten copper is charged into the receiving chamber 2 and the tapping chamber 3, and the vacuum evacuation device 15 is operated. When the molten copper is evacuated to a vacuum, the molten copper fills the rising pipe 8 and the descending pipe 9 and flows into the bottom of the connecting chamber 10. Therefore, inert gas inlet 11
When an inert gas such as argon is blown into the riser pipe 8, the molten copper in the riser pipe 8 is driven by the blown gas and flows upward, passing through the connection chamber 10 and reaching the downcomer pipe 9. Since a flow is formed, the flow from the molten metal inlet 4 to the receiving chamber 2
If molten copper is continuously supplied into the chamber, the following vacuum degassing will be performed continuously. That is, the molten copper is vigorously stirred by the blown gas, and a vacuum degassing reaction is actively performed within the connection chamber 10. Furthermore, by continuously introducing the additive S into the connection chamber 10 from the additive inlet 16, the alloying elements of the molten copper can be made uniform. Connection room 10
The flow rate of molten copper passing through can be controlled by adjusting the amount of gas blown from the inert gas blowing port 11 and the amount of current applied to the electromagnetic coil 20 . When the molten copper that has passed through the connection chamber 10 descends in the downcomer pipe 9, it is subjected to the induction stirring action by the electromagnetic coil 13, and passes through the tapping chamber 3 as degassed molten copper with a uniform component distribution, and then exits from the molten metal outlet 6. It is continuously supplied to subsequent refining equipment. If the inner diameter of the downcomer pipe 9 is made larger than the inner diameter of the riser pipe 8 (preferably 1.5 times or more the inner diameter of the riser pipe 8), the time required for the molten copper to pass through the descender pipe 9 can be lengthened, and This is particularly preferred because the molten copper in the tube 9 can be sufficiently stirred and the components and temperature can be made uniform.

Next, FIG. 2 shows an embodiment of the second invention, except that in addition to the inert gas inlet 11 in the embodiment described above, an electromagnetic coil 22 surrounding the middle part of the riser pipe 8 is provided. It has the same configuration as the example, and the same parts as in FIG. 1 are denoted by the same reference numerals as in FIG. 1.

In the continuous vacuum degassing device 23 of this embodiment, the rising drive of the molten copper in the riser pipe 8 and the control of the flow rate of the molten copper are carried out by blowing gas from the inert gas suction port 11 and using the electromagnetic coil 22.
The other effects are the same as those in the previous embodiment.

FIG. 3 shows an embodiment of the fourth invention, in which the furnace body 1 is provided with a single storage chamber 24 communicating with the molten metal inlet 4 and the molten metal outlet 6, and the lower ends of the ascending pipe 8 and the descending pipe 9. The structure is the same as that of the embodiment shown in FIG. 2, except that the part is inserted into this storage chamber 24, and the same parts as in FIG. 2 are denoted by the same symbols as in FIG. 2. .

In the continuous vacuum degassing device 25 of this embodiment, the molten copper flowing from the molten metal inlet 4 is temporarily stored in the storage chamber 24 and subjected to the following vacuum degassing process at the molten metal outlet 4. is continuously supplied to the outside.

That is, in the same way as the embodiment shown in FIG. When the additive S is added, the molten copper is vacuum degassed while forming a circulation flow from inside the storage chamber 24 through the rising pipe 8, the connecting chamber 101 and the downcomer pipe 9 and returning to the storage chamber 24.

Note that if the electromagnetic coil 22 is removed from the apparatus shown in FIG. 3, the apparatus according to the third embodiment of the invention can be obtained.

The present invention is not limited to the above-described embodiments, but may include, for example, using a shallow horizontal tank-like body as the connection chamber 10.
The shape, material, etc. of each part may be other than those mentioned above. Further, the electromagnetic coil 13 provided in the downcomer pipe 9 portion may be omitted. Furthermore, as shown in FIG. 1, the portions not in contact with or immersed in molten copper may be covered with an outer wall 26 made of a metal plate such as mild steel, stainless steel, heat-resistant steel, etc. to improve sealing performance.

(Effects of the Invention) As explained above, according to the present invention, molten copper can be directly supplied from a melting furnace etc. to a receiving chamber, and then passed through the furnace main body, riser pipe, connection chamber, and downcomer pipe once or multiple times. After degassing and adjusting the composition during the flow process, it is directly supplied to the subsequent refining equipment or casting equipment, so it can be vacuum degassed continuously without the need to transport the molten metal in a ladle or the like. This allows for large labor savings and improved vacuum degassing productivity, and eliminates the need for transportation equipment such as cranes, making the gas equipment itself and vacuum evacuation equipment more compact. Therefore, equipment costs are reduced.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of a continuous vacuum degassing apparatus showing an embodiment of the first invention, Fig. 2 is a view corresponding to Fig. 1 showing an embodiment of the second invention, and Fig. 3 is a view of the fourth invention. FIG. 2 is a diagram corresponding to FIG. 1 showing one embodiment. 1... Furnace body, 2... Hot water receiving chamber, 3... Hot water tapping chamber, 4
... Molten metal inlet, 6... Molten metal outlet, 8... Rising pipe,
9... Descending pipe, 10... Connection chamber, 11... Inert gas blowing port, 14... Exhaust port, 15... Vacuum exhaust device, 16... Additive inlet, 21... ... Continuous vacuum degassing device, 22... Electromagnetic coil, 23... Continuous vacuum degassing device, 24... Storage chamber, 25... Continuous vacuum degassing device, 26... Outer wall.

Claims (1)

[Scope of Claims] 1. A furnace body having a receiving chamber communicating with a molten metal inlet and a tapping chamber communicating with a molten metal outlet, a riser pipe having a lower end inserted into the receiving chamber, and a rising pipe having a lower end inserted into the receiving chamber; A descending pipe inserted into a tapping chamber and a connecting chamber connecting the upper end of the rising pipe and the upper end of the descending pipe are provided, and the connecting chamber is provided with an additive inlet and an exhaust port, and the exhaust port A continuous vacuum degassing device for molten copper, characterized in that the riser is connected to a vacuum evacuation device, and an inert gas inlet is provided in the middle of the riser pipe. 2. The continuous vacuum degassing apparatus for molten copper according to claim 1, wherein the inner diameter of the downcomer pipe is at least 1.5 times the inner diameter of the riser pipe. 3. A furnace body having a receiving chamber communicating with the molten metal inlet and a tapping chamber communicating with the molten metal outlet, a riser pipe having a lower end inserted into the receiving chamber, and a rising pipe having a lower end inserted into the tapping chamber. The method comprises a downcomer pipe and a connection chamber that connects the upper end of the riser pipe and the upper end of the downfall pipe, the connection chamber is provided with an additive inlet and an exhaust port, and the exhaust port is connected to a vacuum exhaust device. A continuous vacuum degassing apparatus for molten copper, characterized in that an inert gas inlet and an electromagnetic coil for driving the molten metal are provided in the middle part of the riser pipe. 4. The continuous vacuum degassing apparatus for molten copper according to claim 3, wherein the inner diameter of the downcomer pipe is at least 1.5 times the inner diameter of the riser pipe. 5. A furnace body equipped with a storage chamber communicating with a molten metal inlet and a molten metal outlet, a riser pipe whose lower end is inserted into the storage chamber, a downcomer whose lower end is inserted into the storage chamber, and a riser pipe whose lower end is inserted into the storage chamber. A connecting chamber is provided for connecting the upper end of the downcomer to the upper end of the downcomer, and the connecting chamber is provided with an additive inlet and an exhaust port, and this exhaust port is connected to a vacuum evacuation device. A continuous vacuum degassing device for molten copper, characterized by having an inert gas inlet in the section. 6. The continuous vacuum degassing apparatus for molten copper according to claim 5, wherein the inner diameter of the downcomer pipe is at least 1.5 times the inner diameter of the riser pipe. 7. A furnace body equipped with a storage chamber communicating with a molten metal inlet and a molten metal outlet, a riser pipe whose lower end is inserted into the storage chamber, a downcomer whose lower end is inserted into the storage chamber, and a riser pipe whose lower end is inserted into the storage chamber. a connecting chamber connecting the upper end of the downcomer to the upper end of the downcomer; the connecting chamber is provided with an additive inlet and an exhaust port; the exhaust port is connected to a vacuum evacuation device; A continuous vacuum degassing device for molten copper, characterized by having an inert gas inlet and an electromagnetic coil for driving the molten metal. 8. The continuous vacuum degassing device for molten copper according to claim 7, wherein the inner diameter of the downcomer pipe is 1.5 times or more the inner diameter of the riser pipe.