JPH0683887B2 - Multiple method for taking castings by centrifugal die casting - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a centrifugal casting method in which casting is performed by pouring molten metal into a mold and rotating the mold, and a plurality of castings are produced by pouring once. The present invention relates to a method for obtaining a plurality of cast products that can be manufactured simultaneously.

2. Description of the Related Art Centrifugal casting method is widely adopted as one of the means for casting a dense cast product having few casting defects such as shrinkage cavities and blow holes. This centrifugal casting method, the molten metal is poured into the mold while rotating the mold at a high speed around the center of rotation, and the molten metal is adhered to the inner wall surface of the mold cavity in a layered manner by the centrifugal force during the mold rotation, It is one of the casting methods for producing hollow or other annular cast products such as cast iron pipes and ball valves.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In the conventional centrifugal casting method that is generally practiced, the molten metal is poured into a single cavity that is provided in the mold. 1
Only individual castings could be produced. For this reason, when it is necessary to cast a large number of ball valves and other annular castings such as deformed rings, the pouring work must be repeated by the required number, and the manufacturing efficiency per unit time was low, There was a strong demand for improvement in the field.

Therefore, as disclosed in Japanese Examined Patent Publication No. 37-7706, a plurality of castings have been attempted by a sand type centrifugal casting method. However, in this method, a plurality of sand molds must be prepared in advance, which complicates the preparatory work, and sets a plurality of sand molds, or has a drawback that it takes time to demold a manufactured casting. there were. Moreover, when setting a plurality of sand molds, the sand molds may be damaged, and the quality of the cast product is unstable, which is not practically sufficient.

An object of the present invention is to provide a method for collecting a plurality of castings by centrifugal mold casting according to the present invention, which has been proposed in order to satisfactorily solve the above-mentioned problems. It is an object of the present invention to make it possible to manufacture a plurality of cast products by casting, to improve the work efficiency in the field and to reduce the manufacturing cost per piece.

Means for Solving the Problems In order to achieve the above object, a method for taking a plurality of cast products by centrifugal mold casting according to the present invention is a pair of dicetable molds,
A plurality of cavities corresponding to the external shape of the cast product are used as a mold with a split mold formed so as to communicate with each other in the axial direction of the rotation center, and the molten metal is supplied to the cavities and the mold is used. It is characterized in that a plurality of castings are cast at the same time by rotating.

Example Next, a method for obtaining a plurality of castings by centrifugal die casting according to the present invention will be described below with reference to the accompanying drawings in relation to specific means for carrying out the method. FIG. 1 shows a schematic longitudinal section of a mold used in a centrifugal casting machine in which the method of the present invention can be suitably carried out, and FIG. 2 shows an axial end face of the mold in FIG.

In the figure, reference numeral 10 indicates a mold used in a known horizontal centrifugal casting machine (not shown), and the mold 10 is composed of a long cylindrical body made of a metal material that can be repeatedly used, and includes a pair of upper and lower parts. It consists of an upper mold 12 and a lower mold 14 that can be divided into halves. On the inner surface of one of the split molds 12, a plurality of recesses 12a are provided in a recessed relationship so as to be adjacent to each other along the axial direction, and the other split mold 14 also has a plurality of recesses along the axial direction. The recesses 14a are provided so that they are successively adjacent to each other.
Then, the split molds 12 and 14 are united on their split surfaces as shown in the drawing, and the plurality of recesses 12a and 14a described above are opposed to each other, so that the inside of the mold 10 has a longitudinal axis of a rotation center. A plurality of cavities 16 adjacent to each other at predetermined intervals in the direction are defined. The inner surfaces of the plurality of cavities 16 define the outer shape of a cast product, such as a ball valve, which requires casting as described above, and each cavity 16 is independent as shown in FIG. They are designed to communicate with each other along the axis of rotation without forming a closed space.

A hollow boss that is detachably mounted on a centrifugal casting machine (not shown) and rotatably supports the mold at both ends of the mold 10.
18 and 18 have been received and fixed respectively. The opening diameter of the through hole 20 penetrating in the axial direction of each hollow boss 18 is set to a dimension that allows a pouring pipe 22 described later to be inserted without contact, and the through hole 20 is It is adapted to spatially communicate with the cavity 16 adjacent to the hollow boss 18. The pouring pipe 22 communicates with a molten metal supply source (not shown), and supplies the molten metal to the plurality of cavities 16 through the nozzle holes 24. Further, in the horizontal centrifugal casting machine, the pouring pipe 22 is arranged so as to horizontally extend through the through hole 20 of the hollow boss 18 in the horizontally arranged mold 10.

The nozzle holes 24 are bored in the required number in the circumferential direction of the pouring pipe 22, and the perforation intervals are as shown in FIG. The size is set to correspond to the center. Further, the pouring pipe 22 is sealed around the through hole 20 of the hollow boss 18 by an appropriate sealing means (not shown), and the pouring pipe 22 is cast as necessary during pouring or when pouring is completed. It is constructed so that it can be slowly pulled out horizontally from 10.

Operation of the embodiment In order to perform centrifugal casting using the mold 10 having the above-mentioned configuration, the mold 10 obtained by combining the divided molds is inserted into the rotary table of a horizontal centrifugal casting machine (not shown) through the hollow boss 18. It is rotatably mounted, and a pouring pipe 22 is horizontally inserted into the through hole 20. Then, the mold 10 is rotated around its horizontal central axis, and the molten metal is injected toward the corresponding cavity 16 from the nozzle hole 24 of the pouring pipe 22. This makes the cavity
The molten metal poured into 16 is diffused to the inner wall surface of the cavity with a required thickness by the centrifugal force when the mold is rotated, and a ball valve having a required size and shape is cast. Then, after pouring the molten metal and solidifying the molten metal, the upper and lower molds 12, 14 are removed, and the ball valve, which is a high-quality cast product 26 with a fine structure and few defects,
A large number of cavities 16 are simultaneously manufactured.

In this embodiment, the molten metal may be injected when the mold is stopped, and the mold may be rotated after the start of pouring or after the completion of pouring.

EFFECTS OF THE INVENTION As described above, according to the method of the present invention, it is possible to simultaneously obtain a large number of a plurality of castings with high quality in one casting at the time of carrying out the centrifugal casting method, and to divide the two-piece halves. Since only the mold is used, the setting of the mold and the taking out of the cast product can be performed easily and quickly, so that the work efficiency on site can be dramatically improved and the manufacturing cost per piece can be reduced. Moreover, since the mold is composed of split molds and can be used repeatedly, there is an advantage that the running cost can be reduced. In this embodiment, the case of using the horizontal centrifugal casting machine has been described, but it can be suitably applied as it is to the vertical centrifugal casting machine for casting the molten metal by rotating the mold around the vertical central axis. Is.

[Brief description of drawings]

1 is a schematic longitudinal sectional view of a mold used in a centrifugal casting machine for carrying out the method of the present invention, FIG. 2 is an axial end view of the mold in FIG. 1, and FIG. 3 is a view of carrying out the method of the present invention. It is a mold longitudinal section showing a state where an annular casting was cast in the cavity of the mold. 10 …… Mold, 12 …… Upper mold 14 …… Lower mold, 16 …… Cavity 18 …… Hollow boss, 20 …… Through hole 22 …… Molten pipe, 24 …… Nozzle hole

Claims (1)

[Claims] 1. A pair of molds (12, 14) which can be divided into a plurality of cavities (16) corresponding to the external shape of a cast product (26).
Is used as a mold (10), which is formed so as to communicate with each other in the axial direction of its rotation center, and the molten metal is supplied to the cavity (16) and the mold (10) is rotated. This allows multiple cast products (2
A method for multiple castings by centrifugal mold casting, characterized in that 6) is cast at the same time.