JPS58159964A - Method for casting internally flanged pipe - Google Patents

Abstract

PURPOSE:To melt stick a ring for an inside flange firmly to the inside surface of a pipe in the stage of producing an internally flanged pipe by a centrifugal casting method, by supporting the ring for forming the internal flange in a metallic flask for casting, and regulating the rotation of the flask and the ring specifically in the stage of charging molten metal into the flask through a charging spout and casting the pipe centrifugally. CONSTITUTION:A ring 4 for an internal flange which is beforehand made in a metallic flask 1 for centrifugal casting is held by the holding jaws 7 of a holder 14 in the outside part and is held concentrically in the flask 1. While the flask 1 and the ring 4 are rotated, molten metal is charged into the flask through a charging spout 2, whereby a pipe is cast centrifugally. In this case, the number of revolutions of the flask 4 is set differently from the number of revolutions of the ring 4, and the number of revolutions of the ring 4 is synchronized with the number of revolutions of the flask 1 according to the solidification of the molten metal. The molten metal on the surface of the ring 4 in contact with the molten metal is changed incessantly by which the contact surface of the ring 4 is melt stuck securely to the inside surface of the pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides #! The present invention relates to a method for casting an inner flange tube having II.

When obtaining a tube body by a casting method, the centrifugal force casting method is most frequently used. In order to obtain such an inner flange tube by centrifugal force casting, an end plate or the like is used in a centrifugal casting frame (mold) to insert a ring made in advance of the same material as the casting tube material. , set in a predetermined position by fastening means such as bolts, and by casting molten metal while rotating the centrifugal casting frame in the usual manner, the ring is cast with the molten metal, and the tube body is ilI! It is customary to obtain I by K. However, this conventional method has a problem in that it is not possible to completely fuse and integrate the rings. That is, in this method, when the molten metal to be cast reaches between the outer surface of the ring and the inner surface of the mold as the metal frame rotates, the molten metal remains stationary with respect to the ring, so the molten metal in contact with the ring In order to melt the surface, heat is absorbed first by the ring side, and solidification tends to start early, making it difficult to sufficiently melt and integrate the two. It is possible to form an uneven surface on the molten metal contact side of the ring, to plate it with easily soluble materials such as zinc or copper, or to add black, but the effect is not sufficient, and Preparation and operation are troublesome.

The present invention has been made to solve these problems, and its characteristics include V! , a ring serving as an inner flange is supported at a predetermined position in a centrifugal casting metal frame from the outside of the metal frame, and the ring is placed in contact with the molten metal that is cast into the metal frame and rotates with the rotation of the metal frame. is rotated concentrically with the metal frame and at a rotational speed different from the metal frame rotational speed.Then, as the molten metal solidifies, the ring rotational speed is synchronized with the metal frame rotational speed, thereby casting the ring. The point is to obtain a inner tsuba tube.

The present invention will be described in detail below with reference to the illustrated embodiment. FIG. 1 shows an example of an inner flange tube, in which the inner circumferential surface of the tube body has a #! The part@koma is integrally formed. In order to obtain such an inner flange tube by the centrifugal force casting method, a separate ring casting means as illustrated in FIGS. 2 and 3 has conventionally been used. That is, in both figures, using the centrifugal casting mold (mold) fl)K end play) No. 1), the ring (4) that will become the crocodile part is clamped with a support (6) such as a fastening bolt. Set it in the fixed position, pour 1m1 of molten metal from the pouring gutter, and place the metal frame (1).
Through the rotation of the ring (4) and the metal frame (11
Then, by melting the outer circumferential surface of the ring (4) using the heat of the molten metal and casting it together, the two are integrated and the inner flange pipe as shown in Fig. K11 is obtained with the droplet solidification. However, as mentioned earlier, in the cast-in state, the molten metal m rotating between the metal frame (1) and the ring (4) is in a stationary state, and is heated by the ring (4) K in contact with it. The molten metal that has been deprived of molten metal begins to solidify, and the power to melt the contact surface of the ring (4) is weak.

Its complete integration into one piece is what sets it apart.

In contrast, the present invention proposes new means as illustrated in FIGS. 4 and 5.

That is, in Fig. 4, (1) shows the centrifugal casting metal frame, (ri) shows the pouring Gl, and ii) shows the end play F, and these V
i Similar to Fig. 2.3, it is completely similar to that of the conventional centrifugal casting machine, but in the present invention, the cast-in ring (4) is set and held at a predetermined position in the metal frame (1), and A support device (B) capable of imparting rotation to the front ring (4) is installed outside the metal frame (11).The support device TJ4 is mounted on the moving rail (B). Wheel(
The main body is mounted so that it can freely move forward and backward in the direction of the metal frame (g) and the running drive motor (g), and the metal frame (
9 holders (118) are rotatably supported concentrically with the metal frame (1) by the support cylinder part Oη protruding toward the metal frame (1); a ring holding claw (1) that can be expanded and contracted in the radial direction around the center;
In order to expand and contract the retaining claw (7) in the radial direction and to provide QJIK rotation of the holder together with the retaining claw (7), an operating shaft (to) is rotatable around the O-axis and can be moved back and forth in the axial direction.
The ring holding claws (1) are elastically supported in the center direction by springs +all projected from a cylindrical spring holder (9&) located at the center of the metal frame. ) has an operating shaft (to) O engagement head (LOa)
A protruding guide rod (LOb) is slidably inserted, and the engagement head (10 m) has a disc-shaped O shape, and its outer circumferential surface abuts the inner surface of each ring holding claw ( ). It is.

The operating shaft is engaged and inserted into the holder through a spline structure or a key structure, etc. so that it can rotate and move forward and backward, and the other end of the operating shaft is fitted with air for advancing and retracting provided on the main body side. The advancing/retracting rod (8a) of the V cylinder (a) and the connector (8b) provided in the K are connected in a non-rotatable manner, and in order to provide flexible rotational movement to the operating shaft - the coaxial shaft in the middle. The drive motor (b) is connected via a transmission mechanism (2) such as a belt or pulley, and the motor (b) is connected to a torque detection mechanism, a brake mechanism, etc., although it is not shown in the figure. The structure necessary for switching is provided, and (7L) in the figure shows the pin axis for pivoting the ring retaining claw (7) to the holder.

The support device used in the present invention is a casting ring (
4) is held in a predetermined setting device of the centrifugal casting metal frame (1), and when casting is completed, it can be evacuated outside the metal frame 11), and the ring 14) can rotate at variable speeds relative to K. It is of course possible to use a mechanism necessary for this purpose other than the structure illustrated in the illustrated device 04, but the illustrated support device (B)
According to , the following motion can be obtained. That is, when the reciprocating rod (8a) of the air cylinder (11) is set to the retracted position as shown in Fig. 4, the operating shaft is also retracted along with it via the connector (8b), and the locking head (loa) is retracted as shown in FIG. Each ring holding claw (7) of the holder brocade is a pivot pin shaft (7m)
The ring (4) is expanded in the radial direction using the ring as a fulcrum, and the ring (4) is held from the inner surface and set in a predetermined position within the metal frame (1). On the other hand, when the advancing/retracting rod (aa) is moved forward, the result is K.

As shown in Fig. 5, the first operating shaft moves forward together, and as the engagement head (log) moves forward, each ring holding pawl (γ) of the umbrella ring I is moved by the spring (9) to the pivot pin shaft. When Kll is closed in the radial direction with (a) as the fulcrum, the ring (4)
As it separates, the entire body (2) O retreats, causing the ring retaining claw opening to contract and close) V! end play)
The central hole in iiiK can be pulled out to the outside without any problem. In addition, the holder's partial tank is rotated by the operating shaft through the transmission mechanism when the motor is started, and also through the torque detection mechanism and braking mechanism, so that the desired rotational state can be obtained. Each ring retaining claw () from the tank
), the ring (4)K can be arbitrarily given rotation at a rotation speed different from the rotation speed of the metal frame (11) or rotation at the same rotation speed as the rotation speed of the metal frame i1+.

Centrifugal force casting of the inner flange tube O by integrating the l) ring (4) according to the present invention is carried out as follows. Support device
is brought close to the metal frame (1) K, and insert the group of ring holding claws ( ) in the contracted and closed state into the metal frame (1) through the center hole of the end plate 1s), and After the ring (4) is set in a predetermined position, the rotation of the metal frame fl) is performed by expanding and abutting the retaining claw (7) on the inner circumferential surface of the ring (4) that is separately inserted into the ring (4). As soon as the pouring starts, the molten metal (3) is poured by inserting the pouring gutter.
4) is rotated via the holder brocade by rotation of the operating shaft side by the motor (b) and the transmission mechanism 2, and the number of rotations is made different from the number of rotations of the metal frame (1). As a result, the molten metal is brought to the inner surface of the metal frame by centrifugal force due to the rotation of the metal frame fil, and a slip occurs between the contact surface between the ring (4) and the molten metal that rotates 119J with the metal frame (1), so that the molten metal remains stationary. If the ring (4) is replaced constantly, the solidification of the molten metal flow at the contact surface is delayed, and this increases the effect of melting the contact surface of the ring (4). This makes it possible to activate melting.

Therefore, if the slip is made larger, the so-called cavity VM effect will also be added. In this way, the fusion bond between the molten metal and the ring is made more WPTo and more reliable. Next, as the poured molten metal solidifies due to the elapse of O time O after casting, the molten metal! $10 Due to increased viscosity, etc., the torque of the O rotation of the metal frame (1) to rotate the ring (4) through the molten metal (1) increases, but along with this, the rotation speed of the ring (4) increases. is gradually changed in speed to synchronize it with the rotational speed of the metal frame i11, and when the casting of the molten metal is completed, the rotation of the metal frame (1) is stopped, and the rotation of the ring (4) is also stopped to complete the casting. After that, the ring holding claw (7) is closed as shown in Figure 5, and the support device (b) is moved back.
The ring retaining claw (7) is retracted out of the metal frame (1), and the inner flange tube body (2), in which the ring (4) is integrally cast as a flange circle, is taken out. In carrying out the above-mentioned invention, the outer surface of the ring (4) that comes into contact with the molten metal may be formed with an uneven surface in advance, or may be plated with an easily f# fusible composite material such as zinc or copper. Applying flux is free.

According to the method of the present invention, the ring that becomes the inner tsuba (
4) and the molten metal (phantom) that encases it, there is no incomplete fusion, and the inner flange part is completely integrated, ensuring a reliable volume. That is, in the present invention, the ring (
4) is not held in a fixed state so as to rotate in synchronization with the metal frame (1) as in the past, but instead of being held in a fixed state so as to rotate in synchronization with the metal frame (1), the ring (4) By holding and setting the ring in a rotatable state, as the molten metal is poured, the ring (4) is given a rotation speed different from that of the metal frame (1). The ring (4) and It is possible to obtain complete fusion and integration of the parts, eliminate peeling of the inner p1 part due to incomplete fusion and other ◆ defects, and in terms of strength, it is possible to obtain a solid and strong inner flange part without L7 alignment. It can be done.

[Brief explanation of drawings]

Figure 311 is a side sectional view of the main part of the inner flange pipe, Figure 2.3 is a side sectional view of each main part showing conventional cast-in ring fixation and centrifugal casting.
FIG. 4 is a vertical sectional side view of the main part showing an embodiment of the method of the present invention, and FIG.
The figure is a side cross-sectional view of the main part showing the ring support released state. (1)...Centrifugal casting metal frame, (2)...Pouring gutter, (1
)...Molten metal, (4)...Ring, (5)...End plate, 17)...Ring holding claw i11...Air V cylinder for advancing and retracting the operating shaft, (9)...Spring , scream...
Operating shaft, Ql)...Motor for rotating the operating shaft, (B)...
・Guide rail, aI... travel drive motor, (b)
...Support device. Patent applicant Kubota Iron Works Co., Ltd. Figure 7 Figure 4 Figure 2 Figure 3 Figure 5

Claims (1)

[Claims] 1. A ring serving as an inner flange is supported at a predetermined position within a centrifugal casting metal frame from the outside of the same metal frame, and the ring is placed in contact with the molten metal that is cast into the metal frame and rotates with the rotation of the metal frame. The ring is rotated concentrically with the metal frame and at a rotational speed different from the metal frame rotational speed, and then as the molten metal solidifies, the ring rotational speed is synchronized with the metal frame rotational speed, and the shilling is cast. An inner flange tube casting method featuring: