JPH02307649A - Method and device for continuously casting copper and copper alloy - Google Patents

Abstract

PURPOSE:To enable the casting of a copper and copper alloy ingot without any flaw without using flux by interposing a heat resistant ring into a connecting part at molten metal side between a heat resistant material and a mold and solidifying molten metal filled up in pouring basin part into the mold. CONSTITUTION:The pouring basin part 3 surrounded with the heat resistant material 4 at upper part of the mold 1 is disposed and the molten metal 6 supplied into the pouring basin part 3 is cooled from the surrounding of the mold while preventing the molten metal from infiltration into the connecting part with the heat resistant ring 5 interposed into the connecting part at molten metal side between the heat resistant material 4 and the mold 1 and solidified under condition of interrupting air. Further, preceding to the start of the casting, lubricator of graphite, silicone oil, etc., are applied on the inner face of the copper-made mold 1. Consequently, the involution of oxide, etc., does not occur and further, the consumption of the lubricator is extremely reduced and the use of flux for maintaining oxide prevention and supporting the lubrication is eliminated and the flaw phenomenon can be perfectly prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for continuous casting of copper and copper alloys. More specifically, the present invention relates to a continuous casting method and apparatus for producing ingots without surface defects without using flux.

[Prior Art] Conventionally, continuous casting of copper and copper alloys uses a copper mold 1 equipped with a water-cooled jacket 1-2, as shown in FIG. This was done by injecting flux 10 from above and continuously casting while supplying flux 10 to the surface of the molten metal.

In this case, the use of flux was indispensable as it not only keeps the surface of the molten metal in the mold warm and prevents oxidation, but also functions as a lubricant.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional continuous casting, the flux may get caught up in the molten metal and cause defects due to foreign matter, or the flux or oxides may adhere to the surface of the ingot 7 and cause the ingot surface to deteriorate. Quality problems often occur, and it has been difficult to completely prevent various defects caused by the use of these fluxes.

The present invention aims to solve the problems of the prior art, and provides a continuous casting method for copper and copper alloys for producing defect-free ingots without using flux, and an apparatus for applying the method. The purpose is to provide

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention, in continuous casting of copper and copper alloy, applies lubricating oil to the inner wall surface of the mold, and then uses a heat insulating material provided above the mold. The molten metal is supplied to the enclosed sump, and is cooled from around the mold while preventing the molten metal from penetrating into the connection by a non-heat-resistant ring inserted in the molten metal side connection between the heat insulating material and the mold. , a method for drawing out the solidified ingot from the bottom of the mold, and a method in which a pool surrounded by a heat insulating material is provided above the mold, and a heat-resistant material ring is inserted between the heat insulating material and the mold on the molten metal side. That is.

[For production]

According to the present invention, a molten metal is provided above the mold and surrounded by a heat insulating material, and the molten metal filled in the molten metal pool solidifies in the mold while being isolated from the atmosphere. Such entanglement will not occur.

Furthermore, the consumption of lubricating oil is extremely low, and if lubricating oil is applied to the inner surface of the mold before starting casting, no further replenishment of lubricating oil is required.

Therefore, the use of flux to support oxidation prevention and lubricity, which are important in the prior art, is no longer necessary.

〔Example〕

Hereinafter, the present invention will be described in detail based on illustrated embodiments.

FIG. 1 is a sectional view showing one embodiment of a continuous casting apparatus according to the present invention, and the same reference numerals are given to the same components as in FIG. 3 showing the conventional example described above.

In FIG. 1, 1 is a copper mold equipped with a water cooling jacket 2, and above the mold 1 is provided a sump 3 surrounded by a heat insulating material 4. Molten metal 6 of copper or copper alloy is supplied from the upper part of the trough 3 via a float 9 from a gutter 8. The molten metal 6 is filled into the sump 3 and starts to solidify in the mold, but the molten metal temperature during casting of copper and copper alloys is, for example, 950 to 950°C.
Since it is as high as 1150°C and has high permeability, it easily penetrates into the gap between the mold 1 and the heat insulating material 4. When molten metal enters the gap,
It causes adverse effects such as solidification and horizontal cracks on the ingot surface.

Therefore, in the present invention, it is an important requirement to insert the heat-resistant material ring 5 into the molten metal side connecting portion between the heat insulating material 4 and the mold 1.

As heat-resistant materials, 5i3N4-ON, 'Zr0241
Ceramics such as N are used effectively. The shape of the heat-resistant material ring 5 is circular, square, or similar to the horizontal cross-sectional shape of the mold, and the cross-section is preferably wedge-shaped as shown in FIGS. 2(a) and 2(b).

Before starting casting, a lubricant such as graphite or silicone oil is applied to the inner wall surface of the copper mold 1. Since the solidification of the molten metal 6 in the mold 1 is performed in a position isolated from the atmosphere by the molten metal filled in the sump 3, there is no entrainment of oxides and the consumption of lubricating oil is extremely low. Therefore, as described above, if a lubricant is applied to the inner wall surface of the mold before the start of casting, casting can be carried out without any further supply of lubricant, and the use of flux becomes unnecessary.

In order to obtain copper and copper alloys with good surface quality, it is best to increase the wall thickness of the heat insulating material 4 forming the pool 3 to maintain the molten metal in the pool 3 at a high temperature. 3 height L
It is desirable to set H to at least 172 times the length LM of the mold 1.

A copper mold with an inner diameter of 262 mm and a length of 380 mm was used as the mold, and the insulation material was 75 mm thick and 200 m high.
Form a pool above the mold using a quartz glass insulation material (heat resistance temperature: 1650°C, thermal conductivity: 0', 88 Kcal/m, Hr, 'σ) at the connection between the mold and the insulation material. Free-cutting brass (Cu 59
．． 30wt, %, Pb 3゜Qwt%, Sn 0.30
%, Fe 0.2 wt %, Zn remaining), a cylindrical ingot with no cracks and a smooth surface was obtained.

Table 1 [Effects of the Invention] As described above, according to the method and apparatus for continuous casting of copper and copper alloys of the present invention, a smooth surface without the adhesion of oxides etc. on the surface can be formed without using flux. High-quality copper and copper alloy ingots with specific properties can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing one embodiment of the present invention, FIG. 2 is a sectional view showing an example of the shape of a heat insulating ring, and FIG. 3 is a longitudinal sectional view showing a conventional casting apparatus. ■... Mold 2... Water cooling jacket 3.
...Hot water pool 4...Insulating material 5...Heat-resistant material ring 6...Molten metal 7...Ingot 8.
... Gutter 9 ... Float 10 ... Flux Ll + ... Height of sump LM ... Mold length Patent applicant Nitto Metal Co., Ltd. agent Patent attorney Masaya Takahata Procedural amendment (voluntary) ) 1. Display of the case 1999 Patent Application No. 128329 2 Title of the invention Continuous casting method and apparatus for copper and copper alloys 3 Person making the amendment Relationship to the case Patent applicant address 11 Taito 4-chome, Taito-ku, Tokyo Number 4'
Name: Shin Nitto Metal Co., Ltd. Representative Director Atsushi Takeuchi 4, Agent: 171-5, "Hana heat-resistant material ring" in the "Detailed explanation of the invention" section of the specification subject to amendment, page 4, line 1 of the specification "..." is corrected to "Heat-resistant ring...". "Casting temperature" on page 7, line 7 of the specification (in Table 1) is corrected to "casting speed."that's all

Claims (1)

[Claims] 1. After applying lubricating oil to the inner wall surface of the mold, supplying molten metal to a pool surrounded by a heat insulating material provided above the mold, and connecting the molten metal side between the heat insulating material and the mold. A continuous casting method for copper and copper alloys, characterized in that the molten metal is cooled from around the mold while a heat-resistant ring inserted in the mold prevents the molten metal from entering the connection part, and the solidified ingot is pulled out from the bottom of the mold. . 2. A continuous casting apparatus for copper and copper alloys, characterized in that a sump surrounded by a heat insulating material is provided above the mold, and a heat-resistant ring is inserted at the molten metal side connection between the heat insulating material and the mold. 3. The continuous casting apparatus for copper and copper alloys according to claim 2, wherein the heat-resistant ring inserted is a wedge-shaped ceramic ring.