JPH0747454A - Centrifugal force casting method - Google Patents

Abstract

PURPOSE:To provide a means which can eliminate such problems as when a molten metal returns to a casting position, this molten metal and the succeedingly casting molten metal which come into collision with each other, and disturbance of the molten metal and scattering of the molten metal, etc., generated, and a casting defect is generated due to its generation. CONSTITUTION:The tip surface part of a molten metal which is cast into a casting mold 1 hits against an annular member 6 installed in an opening part of the opposite side to a casting position of its molten metal and its advance direction is reversed, and immediately before it returns to the casting position, casting of the molten metal is suspended, and thereafter, the tip surface part of the molten metal hits against an annular member 5 installed in an opening part of the casting position side and its advance direction is reversed, and at the time point when it advances to the opening part side of the opposite side, casting of the molten metal is restarted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centrifugal casting method, and more specifically, while rotating a horizontal centrifugal casting mold in which an annular member having a damming function for molten metal is attached to both openings. The present invention relates to a centrifugal casting method in which a molten metal is cast into the mold from one of the both end openings to perform centrifugal casting of a tubular body.

[0002]

2. Description of the Related Art In such a centrifugal casting method,
Conventionally, the operation of casting the molten metal into the mold is performed continuously from one of the both end openings without interruption,
The tubular body was centrifugally cast.

[0003]

As shown in FIG. 2, for horizontal centrifugal casting, annular members 5 and 6 (so-called bands 5 and 6) having a damming function for molten metal are attached to openings at both ends. When the molten metal is continuously cast into the casting mold 1 of No. 1, the cast molten metal is rotated in the casting mold 1 from the casting position.
2) advance to the tip side in the axial direction (see FIG. 2 (a)),
It is reflected by the annular member 6 on the pouring side and returns to the casting side.
Then, when the front surface portion of the molten metal returns to the casting position (see FIG. 2B), the molten metal A that has returned to that position collides with the molten metal B to be cast later, and is extremely disturbed. Cause the flow of molten metal, or the molten metal flies as droplets, and due to the turbulent flow and molten metal scattering, the inclusion of impurities such as slag and coating agents, air, etc. There is a problem that casting defects are generated and a casting unhealthy layer is formed on the inner peripheral portion of the centrifugal casting pipe. The present invention has been made in view of such an actual situation, and an object thereof is to provide means capable of solving the above-mentioned problems.

[0004]

The centrifugal casting method according to the present invention (hereinafter referred to as the present invention method) is intended for horizontal centrifugal casting in which an annular member having a molten metal damming function is attached to both end openings. While rotating the mold, a molten metal is cast into the mold from one of the both end openings, a centrifugal casting method for centrifugally casting a tubular body, wherein the molten metal cast into the mold The tip surface portion reverses the direction of travel by hitting the annular member attached to the opening opposite to the pouring position of the molten metal, immediately before returning to the pouring position, after interrupting the pouring of the molten metal, At the point where the tip surface portion of the molten metal hits the annular member attached to the opening portion on the casting position side to reverse the traveling direction and progresses to the opening portion side on the opposite side, the casting of the molten metal is restarted. It has features.

[0005]

According to the method of the present invention, the front end surface portion of the molten metal which is cast into the mold and advances to the side opposite to the casting position (hereinafter referred to as the "pouring point side") reverses the advancing direction on the pouring side. Immediately before returning to the pouring position by the molten metal, the pouring of the molten metal is interrupted, so that it is possible to avoid the phenomenon that the molten metal returned to the pouring position collides with the molten metal that is cast later as in the conventional case. Therefore, it is possible to prevent a very disturbed flow of the molten metal or the molten metal from being scattered as droplets due to the collision of the molten metal. Further, when the front surface portion of the molten metal hits the annular member on the casting position side and reverses the traveling direction, and proceeds to the opening side on the opposite side, the casting of the molten metal is restarted. However, at the time of restarting the casting, the flow of the molten metal to be cast later is generated without countering the flow of the front surface portion of the molten metal. Therefore, even in this state, there is no disturbance of the molten metal or scattering of the molten metal,
Moreover, by restarting the casting, sufficient molten metal can be filled into the mold as in the conventional case.

[0006]

As described above, according to the method of the present invention, the occurrence of turbulence of the molten metal, scattering of the molten metal, etc. is suppressed, so that impurities, air, etc. caused by the disorder of the molten metal, scattering of the molten metal, etc. Therefore, the conventional problem that the casting unhealthy layer is formed in the inner peripheral portion of the centrifugal casting pipe is eliminated by suppressing the occurrence of casting defects such as the above, and thus the object of the present invention is achieved.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the portions denoted by the same reference numerals as the conventional example indicate the same or corresponding portions.

In FIG. 1, reference numeral 1 is a horizontal centrifugal casting mold (specifically, a cylindrical metal frame), and the mold 1 is
The engaging recesses 1a and 1b are carried while being locked by the supporting rollers 2 and 3 which are rotationally driven by a driving device (not shown),
It is adapted to rotate following the rotation of the support rollers 2 and 3. A centrifugal casting trough 4 for receiving the molten metal from a ladle (not shown) and casting the molten metal into the mold 1 at one end opening (the left side opening in FIG. 1) of the mold 1.
Is provided with its tip facing the inside of the mold 1. The centrifugal casting trough 4 is equipped with a stopper 4a that can be freely opened and closed. Further, annular members 5 and 6 (so-called bands 5 and 6) that function as dams for the molten metal cast via the centrifugal casting trough 4 are attached to the openings of both ends of the mold 1. ing.

In such a casting apparatus, when the molten metal is cast into the mold 1 from the casting position where the annular member 5 on the molten metal side is mounted, the tip surface portion a of the cast molten metal is shown in FIG.
As shown in (a), it advances to the tip side while rotating in the mold 1, but according to the method of the present invention, the tip surface portion a of the molten metal hits the tip end side annular member 6 and advances. Immediately before reversing the direction and returning to the casting position, the stopper 4a is operated to interrupt the casting of the molten metal as shown in FIG. Therefore, the molten metal A that has returned to the casting position is the molten metal B that is cast later as in the conventional case (see FIG.
The phenomenon of collision with (C) can be avoided. Therefore, it is possible to prevent a very disturbed flow of the molten metal or the molten metal from being scattered as droplets due to the collision of the molten metal.
In order to detect the progress of the front end surface portion a of the molten metal in the mold 1, for example, a high-sensitivity camera capable of monitoring the inside of the mold 1 may be used. Furthermore, according to the method of the present invention, when the front end surface portion a of the molten metal hits the annular member 5 on the molten metal base side to reverse the traveling direction and to advance to the molten metal tip side, the stopper 4a is operated to perform the casting. However, at the point of time when the casting is restarted, the flow of the molten metal B to be cast later is generated without countering the flow of the front surface portion of the molten metal, as shown in FIG.
Therefore, even in this state, the disorder of the molten metal and the scattering of the molten metal do not occur, and moreover, by restarting the casting,
A sufficient amount of molten metal is filled in the mold 1 as in the conventional case. The above-mentioned operation is repeated as long as there is a possibility that the melt is disturbed or the melt is scattered.

It should be noted that although reference numerals are given in the claims for convenience of comparison with the drawings, the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an implementation state of a method of the present invention.

FIG. 2 is an explanatory diagram showing an implementation state of a conventional method.

[Explanation of symbols]

 1 Mold 5, 6 Annular member

Claims (1)

[Claims] 1. A horizontal centrifugal casting mold (1) in which annular members (5), (6) having a molten metal blocking function are attached to both end openings while rotating one of the both end openings. Is a centrifugal casting method in which the molten metal is cast into the mold (1) from the mold to centrifugally cast a tubular body, and the tip surface portion of the molten metal cast into the mold (1) is Immediately before returning to the pouring position by hitting the annular member (6) attached to the opening on the side opposite to the pouring position of the melt, the casting direction of the melt is interrupted, and then the tip of the melt A centrifugal force that restarts the casting of the molten metal when the surface portion hits the annular member (5) attached to the opening on the casting position side to reverse the traveling direction and progresses to the opening portion on the opposite side. Casting method.