JPH09323253A - Method and apparatus for polishing inner surface of high-pressure gas container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase polishing force and improve the workability of polishing by rotating a high pressure gas cylinder by eccentricity after putting an abrasive material and polishing auxiliary liquid into the cylinder so that the movement of the abrasive material becomes accelerating movement in the direction reverse to the direction of rotation of the cylinder partially. SOLUTION: First, a proper amount of an abrasive material 7 for rough finish and a proper amount of polishing auxiliary liquid 8 are mixed and put in a cylinder 1. Next, the cylinder 1 is put sideways, and an eccentric axis Y which is eccentric by eccentricity distance L from a central axis X of the cylinder 1 is rotated by eccentricity as a rotary axis. Then, the movement of the abrasive material 7 in the cylinder 1 is affected by speed vector which faces opposite to cylinder speed vector which is added by eccentric rotation of the cylinder 1 in addition to conventional drop vector and becomes accelerating movement in the opposite direction to the direction of rotation of the cylinder 1 partially. Consequently, directivity of the movement of the abrasive material 7 becomes active. In particular, possibilities of contact of the abrasive material 7 with an inner face in a corner part of the cylinder are increased, and friction polishing force for the inner face is increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for polishing the inner surface of a high pressure gas container.

[0002]

2. Description of the Related Art In recent years, a steel seamless container is generally used as a container for storing high-pressure gas. This steel seamless container is mainly made of alloy steel, stainless steel, etc., has an internal volume of about 5 to 100 liters, and is equipped with a valve for charging and discharging gas at one end or both ends. ing. Figure 5 is an example of this,
1 is a container, 2 is a valve protection cap attached to the mouth of a head 3 which is one end of the container, and 4 is a container 1
Shows the bottom of the.

By the way, the high-pressure gas used in the semiconductor industry and the like is increasingly required to have ultra-high purity. The higher the purity of the gas, the more important the surface roughness of the inner surface of the container 1 that stores the gas. If the surface roughness is poor, dust or water will be trapped in the depressions, which will reduce the purity of the gas. Therefore, at present, the inner surface of the container 1 is polished by various methods to adjust the surface roughness to match the gas purity.

As a method of polishing the inner surface of the container 1 as described above, conventionally known methods are the rotation type shown in FIG.
It is a revolution orbit type. The rotation type is a method in which the container is rotated with the central axis of the container 1 as the rotation axis, and polishing is performed at the contact surface between the abrasive 5 charged in the container and the inner surface of the container. In this method, the required surface roughness is obtained. However, there is a problem in that the polishing power is weak to obtain the above-mentioned properties, and therefore it takes a long time to polish.
Further, the rotation and revolution type is a method in which a plurality of attached containers 1 are revolved and rotated, a centrifugal force is applied to the abrasive 5, and the abrasive 5 is abraded by the contact surface between the abrasive 5 and the inner surface of the container. In this case, there is no problem like the rotation type, but the workability of attaching and detaching the container 1 to and from the polishing device is extremely poor, and it takes time to perform the work, and the polishing device has a solid structure that can withstand centrifugal force. There is a problem of being requested. Figure 6,
7 and 6 are polishing auxiliary liquids, which are loaded into the container together with the abrasive 5 during polishing.

[0005]

SUMMARY OF THE INVENTION Therefore, the present invention solves the above-mentioned conventional problems, can increase the polishing power, and has a high workability of polishing. The purpose is to provide a device.

[0006]

In order to achieve the above object, the invention of claim 1 is such that an abrasive material and a polishing auxiliary liquid are charged into an empty high-pressure gas container, and then a predetermined amount is obtained from the central axis of the container. The container is eccentrically rotated about the eccentric axis that is eccentric to the distance as an axis of rotation, so that the movement of the abrasive in the container is partly accelerating in the direction opposite to the rotating direction of the container. .

According to a second aspect of the present invention, a drive motor for rotating the container is provided, and the container to be ground on the rotary shaft of the motor is attachable / detachable such that the center axis of the container is eccentric to the center axis of the rotary shaft. A storage cylinder having a front end opening to be stored is mounted substantially horizontally, and a chucking member for chucking the stored container is provided in the front end opening of the storage cylinder.

[0008]

1 (A) is a schematic diagram showing an eccentric rotation system of a container according to an embodiment of the present invention, and FIG. 1 (B) is a schematic diagram showing movement of an abrasive or the like in the container. is there. The polishing method according to the present invention is tumbling polishing, and includes two steps, a rough polishing step and a finishing step. This tamping polishing will be specifically described. First, a predetermined rough finishing abrasive 7 and an auxiliary polishing liquid 8 are mixed in an appropriate amount and charged into the empty container 1 through its mouth. The rough polishing abrasive 7 is made of a material such as a molten aluminum oxide product or an alumina sintered product,
The shape is also various, such as triangular, quadrangular, rhombic, and granular.

After the polishing material 7 and the polishing auxiliary liquid 8 are charged as described above, the container 1 is eccentrically rotated with the eccentric axis Y which is eccentric by a predetermined distance from the central axis X of the container 1 as a rotation axis. Let This eccentricity distance (amount of eccentricity) L is as shown in FIG. 1 (A), which is obtained as a distance from the central axis X of the container 1, and is smaller than the radius of the container 1. The state of each rotational position in FIG. 1A is shown in FIGS.
Is shown in These figures, especially Figure 2 (C) and Figure 1
As can be seen from (B), due to the eccentric rotation described above, the container 1
In addition to the conventional drop vector B ₁ , the movement of the abrasive 7 within the container is added by the eccentric rotation of the container 1 and the container velocity vector B
_Under the influence of ₂ and the reverse velocity vector B ₃ , a part of the container 1 has an accelerating motion in the direction opposite to the rotating direction of the container 1 (arrow 9).
reference). As a result, the direction of movement of the abrasive 7 becomes active, and in particular, the chances of the corners of the abrasive 7 contacting the inner surface of the container 1 increase, and the frictional abrading force on the inner surface of the container 1 increases. This increase of the polishing force is effective not only on the body of the container 1 but also on the inner surfaces of the head 3 and the bottom 4 on the side surface side, and the same roughness effect as the body can be obtained. Moreover, the polishing area is increased.

When the rough finish polishing is completed, the contents are discharged from the container 1, a polishing agent for the next finishing and a polishing auxiliary material are charged (neither is shown), and the polishing is performed in the same manner. Then, after polishing, the contents are discharged, and the product is obtained by washing and drying the inner surface of the container.

FIG. 3 is a vertical sectional front view of a polishing apparatus for realizing the above-mentioned container eccentric rotation type polishing, and FIG. 4 is a plan view with a part thereof omitted. In this polishing apparatus, a plurality of drive motors 11 for rotating a container are installed in parallel on a base 10. A hollow box-shaped support member 13 is installed in front of each motor 11, and a storage cylinder 15 having a front end opening is supported by a bearing 14 on the front end side in the support member, and a rear end mounting portion 16 is attached to the motor 11. Axis of rotation
It is connected to 17 via a coupling 18 and is rotatably housed in a horizontal direction. The storage cylinder is arranged so that the center axis of the storage cylinder 15 (which is also the center axis X of the container 1) is eccentric with the center axis of the rotation shaft 17 of the motor 11 (which is also the eccentric axis Y). The structure of 15 is formed. A chucking member 20 is provided at the front end opening of the storage cylinder 15 so that the container 1 detachably stored in the storage cylinder 15 can be chucked. 22 in FIG.
Is a safety fence for center guides.

In the polishing apparatus as described above, the container 1 is loaded into the housing cylinder 15 from the rear end side, and after being loaded, the chucking member 20 chucks the substantially intermediate body part thereof. As a result, the container 1 is firmly held at the eccentric position as described above, and the eccentric rotation is possible by the subsequent driving of the motor 11. That is, due to this eccentric rotation, as described above, a part of the movement of the abrasive 7 in the container 1 becomes an accelerating movement in the direction opposite to the rotation direction of the container 1, and the friction polishing force is increased.
This also leads to an increase in the polishing area. In the case of this polishing apparatus, as described above, the container 1 to be polished can be brought into a polishing state simply by loading it from the rear end side into the storage cylinder 15 and chucking it by the chucking member 20. Installation of the container does not take time unlike the rotation and revolution type. It is possible to sufficiently increase the frictional polishing force and increase the polishing area with the same installation time as the rotation type.

The polishing apparatus shown in this embodiment is only a preferable example, and other structures may be used as long as the same effects can be expected. Further, in the embodiment, a plurality of polishing devices are shown, but this is
A single unit may be provided, or a plurality of dozens may be installed in parallel. The most desirable embodiment of the present invention is to install several tens of polishing devices in parallel, and to carry out all the processes from mounting of the container to the devices to rotation by automatic control.

[0014]

As described above, the present invention is as described above, and after the abrasive and the polishing auxiliary liquid are charged into an empty high pressure gas container and the stopper is plugged, the eccentricity is eccentric by a predetermined distance from the center axis of the container. The container is eccentrically rotated with the axis as the axis of rotation, and the movement of the abrasive in the container is partially accelerated, which is opposite to the direction of rotation of the container. Power can be increased and workability is good. Further, according to the polishing apparatus of the present invention, the holding of the container can be performed by one-touch by the chucking member, and the mounting of the container is extremely easy, and a large number of polishing devices are installed in parallel and automatically controlled and operated. There is an excellent effect that it is also possible.

[Brief description of drawings]

FIG. 1 (A) is a schematic view showing an eccentric rotation system of a container according to an embodiment of the present invention, and FIG. 1 (B) is a schematic view showing a movement of an abrasive in the container.

2 (A) to (D) are schematic views showing states of respective rotation positions A, B, C, D of the container in FIG. 1 (A).

FIG. 3 is a vertical cross-sectional front view of a polishing device that realizes polishing of a container eccentric rotation method.

FIG. 4 is a plan view with a part omitted from the above.

FIG. 5 is a vertical sectional front view of a conventional high-pressure gas container with a part thereof omitted.

FIG. 6 is a schematic view showing a conventional rotation type polishing method.

FIG. 7 is a schematic view showing a conventional rotation / revolution type polishing method.

[Explanation of symbols]

 1 Container 2 Cap 7 Rough Finishing Abrasive 8 Polishing Auxiliary Liquid 10 Base 11 Drive Motor 14 Bearing 13 Supporting Member 15 Storage Cylindrical Body 16 Rear End Attachment 17 Rotating Shaft 18 Coupling 20 Chucking Member X Container Center Axis Y Eccentric axis L Eccentric distance (Eccentricity)

Claims (2)

[Claims] 1. An empty high-pressure gas container is charged with an abrasive and a polishing auxiliary liquid, and then the container is eccentrically rotated about an eccentric axis that is eccentric from the center axis of the container by a predetermined distance, and then the container is placed inside the container. The method for polishing the inner surface of a high-pressure gas container, wherein a part of the movement of the polishing material is accelerated in a direction opposite to the rotation direction of the container. 2. A front end opening for removably housing a container rotation drive motor, wherein the rotation shaft of the motor is removably housed so that the center axis of the container is eccentric to the center axis of the rotation shaft. An inner surface polishing apparatus for a high-pressure gas container, wherein a storage cylinder is attached substantially horizontally, and a chucking member for chucking the container stored in the front end opening of the storage cylinder is provided.