JPH11270709A - Ball for ball valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ball for a ball valve reduced in material and machining cost, improved in yield, lightweight and strong, decreased in fluid resistance, eliminating accumulating and precipitation of foreign matter inside, and with no labor required for removing cutting chips and burrs particularly when a stem connecting recessed groove is machined. SOLUTION: A ball 1 for a ball valve is provided with a cylindrical inner wall 3, an outer wall 2 having a surface with an external shape in a circular arc section, a hollow part 11 arranged between the inner/outer walls 3, 2 by abutting an end part of the outer wall 2 closely to an end part of the inner wall 3, a partition wall 4 connecting the inner/outer walls 3, 2 inside the hollow part 11, and a stem connecting recessed groove 9 in the external shape. In this ball 1, the recessed groove 9 is provided on the partition wall 4, and at least its wall thickness in a recessed groove part is formed wider than a width of the recessed groove 9, so as to prevent the recessed groove 9 from communicating with the hollow part 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ball of a ball valve which is mounted on a pipe for water, oil, gas or the like and used for controlling the fluid.

[0002]

2. Description of the Related Art A sheet 2 as shown in a longitudinal sectional view of FIG.
Ball 22 used for ball valve 21 having 2a
Are of various types, each made by different molding methods. Ball 2 shown in longitudinal section in FIG.
Numeral 3 is made by cutting a round bar material or a forged material. This ball 23 has many portions to be cut off, wastes material, requires a lot of processing time, and is expensive. Also, since there is no hollow portion, it is heavy, and particularly large diameter one is extremely heavy.

The ball 24 shown in the vertical sectional view of FIG. 6 is made by casting or welding a plate or tube by press working or the like. I have. However, in the case of casting, defects such as cavities are often found after spherical processing, and the material and processing time are wasted. In addition, since the shape is complicated, it is necessary to increase the thickness in order to improve the flow of the molten metal.

[0004] When a plate or a tube is made by pressing and welding, the relationship between the pipe diameter and the wall thickness is limited.
Generally, it becomes soft and easily deformed, and is difficult to handle. Welding is also a very cumbersome operation because the welds are relatively thin and therefore easily deformed by heat.

The ball 25 shown in the vertical sectional view of FIG. 7 is made by casting or pressing a plate material or a tube material.
Although it can be made lightweight and inexpensive, this ball 25
The flow of the fluid flowing through the inside of the ball 25 is disturbed to increase the fluid resistance, and foreign matter in the fluid is accumulated or deposited in the inside 25a of the ball 25, which is caught between the ball and the seat and hinders the operation of the valve. Spillage or spillage may adversely affect the piping system. In the case of making by casting, there is a problem due to a cavity as in the case of the ball 24 shown in FIG. 6, and in the case of making a plate or tube by pressing or the like, it is soft and easily deformed. Become.

The present inventor has proposed a molding method which has solved various problems in the conventional ball as described above, and FIG. 8 is a longitudinal sectional view thereof (Japanese Patent Laid-Open No. 9-276).
No. 961). In the drawing, the ball 26 has an outer cylinder and an inner cylinder arranged in a double cylinder, and forms an intermediate body having a disk-shaped wall at a substantially central portion in the longitudinal direction. The outer cylinder is formed into a spherical shape by press working, and further subjected to necessary machining and the like to be formed.

[0007]

However, according to this molding method, for example, when the ball 26 is formed by forming a groove in the stem mounting portion 26a, the hollow portion 26b communicates with the outside and the groove is formed in the stem mounting portion 26a. When cutting, cutting chips enter the hollow portion 26b, and the removal thereof is troublesome, and burrs are formed on the cutting portion, and the finishing work for removing the burr is troublesome.

The present invention has been developed in view of the above-mentioned circumstances, and its object is to reduce material costs and processing costs, to improve yield, to be lightweight, and to have excellent strength. The purpose of the present invention is to provide a ball that improves the function of a valve without causing turbulence in a fluid or accumulating or depositing foreign matter in the ball. An object of the present invention is to provide a ball for a ball valve, which does not require the trouble of eliminating the valve, and is therefore less expensive.

[0009]

In order to solve the above-mentioned problems, the present invention has a cylindrical inner wall and an outer wall having a surface whose outer shape is a circular arc in section. A hollow portion is provided between the inner wall and the outer wall in close contact with an end of the ball valve, a partition wall for connecting the inner wall and the outer wall within the hollow portion is provided, and a concave groove for stem connection is provided on the outer shape. In the ball, the concave groove is provided on the partition wall, and at least the partition wall thickness of the concave groove portion is made larger than the width of the concave groove so that the concave groove does not communicate with the hollow portion.

In this case, it is preferable to form a mark for forming the concave groove at the position of the outer shape for forming the concave groove.

[0011] The ball for a ball valve of the present invention is formed by forging a raw material for forging and performing machining to form the outer shape of the ball and a cylindrical through-hole. An economical ball with optimal thickness, strong and not too heavy and does not require excessive material and processing.

Further, when forming the concave groove for connecting the stem by forming a groove, cutting chips do not enter the hollow portion and burrs do not occur.
This makes the ball cheaper.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the ball for a ball valve according to the present invention will be described below with reference to the drawings. FIG.
FIG. 2 is a longitudinal sectional view showing an example of the ball for a ball valve of the present invention, and FIG. 2 is a longitudinal sectional view of the AA section in FIG. FIG. 3 is a longitudinal sectional view showing a state in which the ball shown in FIGS. 1 and 2 is being formed.

In FIG. 3, reference numeral 2 denotes an outer wall, and 3 denotes a cylindrical inner wall. These are arranged in a double cylindrical shape, and an annular partition wall 4 is provided in the middle of the longitudinal direction. Exterior wall 2
The partition wall 4 between the inner wall 3 and the inner wall 3 is later provided with a concave groove 9 for stem connection.
The thickness of the partition wall 4 at this portion is formed wider than the width of the concave groove 9. In the drawing, only the thickness of the concave groove portion of the partition wall 4 is formed larger than the width of the concave groove 9, but the entire wall thickness of the partition wall 4 may be formed thicker.

As described above, a concave groove 9 is formed on the outer surface of the outer wall 2 which is an upper portion of the figure for forming a concave groove 9 for connecting a stem later. Marks (recesses in the figure) 7 for processing are formed. Note that, as described above, when the entire thickness of the partition wall 4 is formed to be larger than the width of the concave groove 9, the mark 7 for groove processing may not be provided.

The forged product in the state shown in FIG. 3 is formed by pressing the outer wall 2 and the end of the inner wall 3 so as to be in close contact with each other.
And a hollow portion 11 is provided between them, and the outer shape of the outer wall 2 is formed into a surface having a circular arc cross section. Further, the partition wall 4 'in the inner wall 3 was removed by machining to form a through hole 8, a concave groove 9 for stem connection was formed, and polishing and plating were performed to complete the structure. This is the ball 1 shown in FIG. Although not shown, the outer shape of the intermediate portion of the outer wall that does not contact the sheet (see 22a in FIG. 4) is left cylindrical, and only the outer shapes of both ends of the outer wall that contact the sheet are formed on a surface having a circular arc cross section. The outer shape of the ball 1 is not limited to a spherical shape.

In FIG. 2, reference numeral 10 denotes a thickened portion. Even if a groove is formed in the concave groove 9 for stem connection by this thickening, the concave groove 9 does not communicate with the hollow portion 11. The hollow portion 11 of the ball 1 is not exposed to the outside.

Further, as shown by a dashed line in FIG. 1, a through hole 12 for communicating the body cavity with the flow path (through hole 8) of the ball 1 may be provided in the inner wall 3. This through hole 12
Also functions to prevent abnormal pressure rise in the body cavity.

Further, a cutout hole 13 may be formed by cutting off a part of the outer shell of the ball 1 which does not come into contact with a sheet, for example, a lower surface portion. The cut holes 13 can further reduce the weight of the ball 1 and contribute to preventing abnormal pressure rise in the body cavity.

As described above, the ball 1 for a ball valve of the present invention is formed by forming a spherical outer shape of a ball and a cylindrical through hole 8 by forging a material for forging and performing machining. It is an economical ball that is free from defects such as cavities, has an optimum thickness, is strong and not too heavy, and does not require excessive materials and processing.

Further, since the cylindrical flow path (through-hole 8) is formed, the flow of the fluid is not disturbed and the fluid resistance is not increased, and foreign matter can be accumulated or deposited in the ball. Absent.

Further, when the concave groove 9 is formed by grooving, cutting chips do not enter the hollow portion 11 and burrs do not occur. The ball 1 becomes cheap.

Also, since the mark (concave 7) for forming the groove 9 for connecting the stem is formed, the groove (concave 7) is obeyed when the concave groove 9 is formed on the spherical material. Thereby, the groove processing of the concave groove 9 can be reliably performed on the partition wall 4. Further, the ball for a ball valve is preferably formed by a warm / hot forging using a copper-based alloy having excellent warm / hot workability as a material.

[0024]

As described above, the ball for a ball valve according to the present invention can reduce material costs, processing costs, etc., improve the yield, and is lightweight and excellent in strength, and generate turbulent flow in a fluid. Improves the function of the valve without raising or accumulating or depositing foreign matter in the ball, especially since cutting chips do not enter the hollow part or generate burrs when processing the groove of the stem mounting part. Therefore, it is possible to provide an inexpensive ball for a ball valve without the trouble of removing these.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a ball for a ball valve of the present invention.

FIG. 2 is a longitudinal sectional view of the AA section of FIG. 1 as viewed in the direction of the arrow.

FIG. 3 is a longitudinal sectional view showing an intermediate body in the process of forming the ball shown in FIGS. 1 and 2;

FIG. 4 is a longitudinal vertical sectional view showing an example of a ball valve.

FIG. 5 is a longitudinal sectional view showing an example of a conventional ball for a ball valve.

FIG. 6 is a longitudinal sectional view showing an example of a conventional ball for a ball valve.

FIG. 7 is a longitudinal sectional view showing an example of a conventional ball for a ball valve.

FIG. 8 is a longitudinal sectional view showing a ball for a ball valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ball for ball valve 2 Outer wall 3 Inner wall 4 Partition wall 9 Recessed groove 11 Hollow part

Claims (1)

[Claims] 1. An inner wall having a cylindrical inner wall and an outer wall having a surface whose outer shape is an arc of a circle. An end of the outer wall is in close contact with an end of the inner wall, and a hollow portion is formed between the inner wall and the outer wall. Providing a partition for connecting the inner wall and the outer wall in the hollow portion, and providing a concave groove for stem connection in the outer shape, wherein the concave groove is provided on the partition, and A ball for a ball valve, wherein a wall thickness of a partition wall of a shaped groove is wider than a width of a recessed groove so that the recessed groove does not communicate with a hollow portion.