JPH0741396B2 - Casting method of copper pipe casted into copper alloy casting - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a method for casting a copper pipe cast into a copper alloy casting to cast a copper alloy casting having a hollow tubular portion which becomes a copper tube through which a cooling medium is passed.

[Prior art]

The casting technique for casting a pipe through which a coolant for cooling is cast is generally called a pipe-casting stuffing method. Among castings cast by such a casting method, there is a press die which is a copper alloy casting, for example. Such a press die is heated by heat generated by plastic deformation of a work such as a mild steel plate, a stainless steel plate, and a titanium plate and frictional heat generated by friction between the work and the press die, and a thermal strain generated by the heating. As a result, the quality of the pressed product related to the dimensional accuracy of the pressed product becomes difficult to maintain. Therefore, in order to keep the press die at a temperature within a predetermined range, it must be cooled. Therefore, the material of the press die is required to have excellent heat transfer properties, so copper alloys with excellent heat transfer properties that are excellent in hardness, wear resistance, and seizure resistance both in Japan and overseas. Is used as a mold material, and a copper pipe or the like is cast by casting to pass a refrigerant. By the way, the most important thing in this casting-cum-casting technology is
When casting a copper alloy mold, because it depends on how much melt loss of the pipe encircled in the casting can be reduced, an extremely large number of methods for preventing melt loss of the encircled pipe have been proposed. Therefore, the melt loss preventing means according to some conventional examples will be outlined below. For example, in Japanese Unexamined Patent Publication No. 62-28058, as shown in FIG. 3 which is an explanatory view of a pipe melting loss prevention means, a wire 2 is wound around the outer circumference of a pipe 1 to be cast, and the wire 2 is wound around 1 to 5 times to form a mold 4. , A method of preventing melting damage of the pipe 1 to be cast is disclosed. Further, in Japanese Patent Application Laid-Open No. 50-123033, as shown in FIG. 4 which is an explanatory view of a pipe melting damage prevention means, a protective plate 2 is welded to the outer periphery of a pipe 1 to be cast, and the outer periphery of the pipe 1 is covered by welding. A method for preventing melting damage of the cast tube 1 is disclosed. Further, in Japanese Patent Laid-Open No. 63-101066, as shown in FIG. 5 which is an explanatory view of a pipe melting loss preventing means, a cast-in pipe 1
Is incorporated into the mold 4, and a method of pouring the refrigerant into the encircled pipe 1 from the refrigerant supply pipe f _p which penetrates the mold 4 and communicates with one end side of the pipe 1 to prevent its melting loss. It is disclosed. As is well understood from the above description, any of the cast-in-mold casting methods mainly focuses on preventing melting damage of the cast-in pipe.

[Problems to be Solved by the Invention]

By the way, when casting a pipe into a copper alloy casting,
If a steel pipe is used, it is extremely effective in preventing melting loss from the viewpoint of its melting point, but it is not practically preferable from the viewpoint of cooling efficiency of a copper alloy casting. Therefore, for a copper alloy casting, a tube made of a material having excellent heat conductivity such as a copper tube is used, but when casting a molten copper alloy into a mold, the copper is melted in terms of the melting point of copper. Naturally, the above-mentioned melting damage prevention means must be taken for the pipe. However, in the first conventional example in which the wire is wound around the outer circumference of the tube among the conventional means for preventing melting of the tube, it takes a long time to wind the wire, which is uneconomical, and the protection around the outer circumference of the tube is required. The second conventional example in which the plate is covered by welding requires a longer time than the first conventional example because it is the method of fixing the protective plate by welding, and the molten metal of the copper alloy does not flow well, so However, there is a problem to be solved that the adhesion is poor. Furthermore, in the third conventional example in which the refrigerant is poured into the pipe that is cast while the molten metal is being cast into the mold, in the unlikely event that the pipe melts and melts into a melt hole, the melt will flow from this melt hole into the melt. There is a risk of causing a steam explosion due to the leakage of the refrigerant, and there was a safety concern during the casting work of the casting. Therefore, it is an object of the present invention to provide a method of casting a copper pipe cast into a copper alloy casting that allows easy and safe casting of a copper alloy casting having a hollow tube portion with excellent cooling efficiency.

[Means for Solving the Problems]

The present invention has been made in view of the above circumstances, and therefore, the gist of the copper pipe cast and round casting method for a copper alloy casting according to the present invention is a copper pipe made of pure copper, from the outer diameter of the copper pipe. Also, a short copper pipe made of a plurality of pure copper of a predetermined length having a predetermined large inner diameter is externally fitted in an adjacent state to create an assembled pipe, and the assembled pipe is bent into a predetermined shape and incorporated into a mold. It is characterized in that a molten metal of a copper alloy having a melting point lower than that of pure copper is cast into a mold incorporating an assembly pipe.

[Action]

According to the copper pipe cast burial casting method according to the present invention, since a plurality of short copper pipes are externally fitted to a copper pipe made of pure copper to create an assembled pipe, this short copper pipe is easily externally fitted to the copper pipe. And, it can be bent easily. Further, in a mold incorporating a short copper pipe bent into a predetermined shape, a molten metal of a copper alloy having a melting point lower than that of pure copper that can obtain a certain fluidity even at a temperature below the melting point of pure copper is cast into the short copper pipes. The molten metal of the copper alloy that enters is cooled by the short copper pipe and further cooled by the partial melting of the short copper pipe to reach the outer peripheral portion of the copper pipe. Then, the melted part of the short copper tube and the molten copper alloy are mixed and solidified.

【Example】

FIG. 1 is an external perspective view of a short copper pipe fitted onto a straight copper pipe before bending according to an embodiment of the present invention, and an assembled state of the copper pipe into a mold for casting a copper alloy mold. With reference to FIG. 2 of the explanatory view, the same components as those of the conventional one and those having the same function will be described below with the same reference numerals. That is, reference numeral 1 shown in FIG. 1 is a copper tube having a large outer diameter × wall thickness = φ22 mm × t3.5 mm made of pure copper having a melting point of 1083 ° C. Wall thickness x length = φ32 mm
A short copper tube 2 having a large diameter of × t2.0mm × L100mm and a short length was externally fitted to form an assembly tube 3. The short copper tube 2 is selected to have an inner diameter such that the copper tube 1 can be easily fitted onto the copper tube 1, and its length is determined by the bending radius of the copper tube 1. is there. It is to be noted that such an assembly pipe 3 is provided on the copper pipe 1 and a plurality of short copper pipes 2
The reason why the structure is fitted to the outside is to facilitate bending of the copper tube 1. Then, the assembly pipe 3 is subjected to a predetermined bending process, and the second pipe
As shown in the figure, this was incorporated into a casting mold 4 for casting a 280 mm × 380 mm × 1500 mm press die (not shown). Then the temperature at which the solid and liquid phases are in equilibrium, or Soli
dus907 ~ 917 ℃, the temperature at which the solid phase is crystallized from the liquid phase in the equilibrium diagram, that is, Liquidus 937 ~ 947 ℃, the melt of the copper alloy with the composition described below, at a low temperature of 1050 ℃ as low as possible and AlBC4 A press die was cast by casting into the mold 4 at a standard casting speed at the time of casting of a kind of casting. That is, this copper alloy is disclosed in Japanese Patent Publication No. 61-43417 filed by the present applicant, and has a composition of Cu-9.0% Al-9.1% Mn-3.1.
% Si-0.7% Co. The casting temperature of the molten copper alloy is set in consideration of the degree of melting of the assembly pipe 3 and the fluidity of the molten copper alloy. In addition to the above copper alloy, for example, the composition Cu-12Al-3Sn-3F
There is one that is represented by the HZ-CE-2FB brand code of e and a copper alloy that is represented by the SO330 brand code of the composition Cu-10Al-9Mn-3Fe-1.5Ni. It is often used as a material. However, the former Solidus
Is 979 ℃, Liquidus is 1025 ℃, and the latter Solidus
Is 985 ° C., and Liquidus is 1028 ° C., the melting point of the copper alloy used in this example is 70 to 80 than the melting point of these copper alloys.
It will be about ℃ lower. First, the press die cast in this way was cut, and the melted state of the cast pipe 3 was examined. As a result, at the time of casting of the press die, a gap is naturally formed between the fitted short copper pipes 2 at the bending portion of the copper pipe 1, and the outer peripheral surface of the copper pipe 1 is directly exposed to the molten copper alloy. However, there was a concern that this portion would be melted, but in the result of the press die cutting examination after casting, almost no melted portion was found in any portion of the copper tube 1. Of course, a part of the short copper pipe 2 fitted on the copper pipe 1 had begun to melt, but solidified in a state where the melted portion and the molten copper alloy were mixed, and the short copper pipe 2 and the copper alloy It was in good contact with the casting body. When the molten copper alloy comes into contact with the short copper pipes 2, the heat required to heat the short copper pipes 2 is removed from the molten copper alloy, while the amount of heat required to melt the short copper pipes 2 is also removed. Therefore, it is understood that the copper pipe 1 does not melt, but a part of the short copper pipe 2 melts out, mixes with the molten copper alloy, and rapidly solidifies. Therefore, as described above, it is only necessary to externally fit the short copper pipe 2 to the copper pipe 1. Therefore, the first conventional example in which the wire is wound around the outer periphery of the pipe or the second outer coating of the pipe by welding is used. It is possible to construct the assembly pipe 3 without requiring a long time as in the conventional example, and since it is not necessary to pour a refrigerant into the pipe as in the third conventional example, it is extremely safe to cast the molten copper alloy into the mold 4. I was able to get in. Next, in the uncut press die, in addition to the copper tube 1 having excellent thermal conductivity, the short copper tube 2 externally fitted to the copper tube 1 has excellent adhesion due to leaching of the copper alloy into the molten metal. By gender
It was confirmed that an extremely excellent cooling effect was obtained.

【The invention's effect】

As described above in detail, according to the copper pipe cast Gurumi casting method to the copper alloy casting according to the present invention, it is only necessary to externally fit a plurality of predetermined length short copper pipes to a copper pipe made of pure copper, As compared with the first conventional example in which wire is wound around the outer circumference of the pipe and the second conventional example in which a protective plate is welded around the outer circumference of the pipe, the work of preventing melting damage of a copper pipe can be performed extremely quickly. In addition, the melt of the short copper cylinder that melts at the temperature of the melt of the copper alloy having a melting point lower than that of the pure copper, which has a certain fluidity even at a temperature below the melting point of the pure copper, mixes with the melt of the copper alloy, and the cooled copper alloy Since it solidifies quickly together with the molten metal, the problem of poor adhesion between the pipe and the casting body due to defective molten metal rotation due to the presence of the protective plate, as in the second conventional example, is also solved. Further, unlike the third conventional example, it is not necessary to pour the refrigerant during the casting of the molten metal into the mold, so that there is no possibility of inducing a steam explosion or the like due to the leakage of the refrigerant. It is possible to expect an extremely great effect on the improvement of the casting work efficiency of the copper alloy casting having the above, the improvement of the quality of the copper alloy casting, and the improvement of the safety during the casting operation.

[Brief description of drawings]

FIG. 1 and FIG. 2 relate to a copper pipe cast-in-turn casting method for a copper alloy casting according to an embodiment of the present invention. FIG. 1 shows a straight copper pipe before bending and a short copper pipe is externally fitted to the copper pipe. FIG. 2 is a perspective view showing the appearance of the assembled copper tube into a mold for casting a copper alloy mold,
3 to 5 relate to a conventional example, FIG. 3 is an explanatory view of a pipe melting loss preventing means of a first conventional example, FIG. 4 is an explanatory view of a pipe melting loss preventing means of a second conventional example, and FIG. FIG. 9 is an explanatory view of a pipe melting loss preventing means of a third conventional example. 1 ... Copper tube, 2 ... Short copper tube, 3 ... Assembly tube, 4 ... Mold.

Claims (1)

[Claims] 1. An assembled pipe is produced by fitting a copper pipe made of pure copper with a plurality of short copper pipes made of pure copper and having a predetermined length and an inner diameter larger than the outer diameter of the copper pipe so as to be adjacent to each other. Then, the assembled pipe is bent into a predetermined shape and incorporated into a mold, and a molten copper alloy having a melting point lower than that of pure copper is cast into a mold incorporating the assembled pipe into a copper alloy casting. Pipe casting and toy casting method.