JPH0274568A - Vacuum-charging of powder into capsule for hip treatment and apparatus therefor - Google Patents

Abstract

PURPOSE:To facilitate the evacuation of a capsule and improve the charging efficiency of powder into the capsule by providing a powder storage container possessed of a weir having holes which do not pass the powder in non-vibrated state, evacuating the storage container and the capsule and transferring the powder from the container to the capsule. CONSTITUTION:A raw material powder 4 is charged into a powder storage container 13. A valve 11 is closed during the above process. A valve 12 is opened to evacuate the container 13. At the same time, the container 13 is vibrated to continuously introduce the powder 4 into a weir 14 in the container 13 little by little through a number of holes 15 of the weir 14. Even if the vacuum degree of the powder 4 is poor in the container 13, it is increased during the passage of the powder 4 through the holes 15. The main body 1 of the capsule is also evacuated parallel to the above operation by opening a valve 10. When the vacuum degrees in the container 13 and the main body 1 reach prescribed levels, the valves 10, 12 are closed and the valve 11 is opened to drop the powder 4 through the weir 14 into the main body 1. The evacuation tube 3 is sealed with a sealing jig 5 and provided to the subsequent HIP treatment process.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method and apparatus for vacuum filling powder into capsules for HIP processing.

(Prior art) Raw material powder such as metal powder or ceramic powder is
In the method of heating, pressurizing, and sintering by IP processing, a method is generally performed in which raw material powder is filled in a container called a capsule, the container is degassed and sealed, and then HIP processing is performed. If the inside of the capsule is not degassed, the residual air inside the capsule may create pores inside the sintered body.
Alternatively, degassing within the capsule is essential since this may cause deterioration of the material of the molded body.

FIG. 3 is a schematic diagram of a conventional process. The vacuum filling method will be explained below based on this.

1) Prepare a capsule body 1 having a degassing tube 3 in the upper lid part 2 and made of metal such as stainless steel, mild steel, or lA (FIG. 3(a)).

2) In air or inert gas atmosphere, raw material powder 4
is filled into the capsule from the degassing pipe 3 (Fig. 3(b)).
.

3) A rubber tube for evacuation is connected to the degassing tube 3, and the inside of the capsule body 1 is degassed using a vacuum pump (not shown). When the inside of the capsule body 1 reaches a predetermined degree of vacuum, the degassing tube 3 is sealed with the degassing tube sealing jig 5 while being evacuated.

Such conventional methods have the following problems.

i) Since the capsule body 1 is evacuated after being filled with the powder 4, the powder increases the exhaust resistance and it is difficult to increase the degree of vacuum inside the capsule body 1. Particularly in the lower part of the capsule body 1, even if the vacuum is applied, the pressure remains almost unchanged from atmospheric pressure, and this tendency is particularly noticeable as the powder becomes finer.

ii) Furthermore, there is a problem in that raw material powder is sucked into the evacuation system during evacuation, which may cause failure of the evacuation device.

As a countermeasure for the above problem i), there is a method of providing grooves on the inner surface of the capsule or attaching a net, as shown in Japanese Patent Application Laid-open No. 62-1n02 or Japanese Patent Application Laid-Open No. 62-274005. However, degassing the center of the capsule takes a long time and is uneconomical. Furthermore, if the powder is fine, degassing is still impossible.

In addition, as a countermeasure for the above problem ii), there is a method of installing a filter in the degassing pipe to prevent the raw material powder from being sucked in, but this causes problems such as an increase in exhaust resistance due to the filter and clogging with the powder.

Furthermore, as a countermeasure to the above problems,
As shown in Publication No. 903, there are two methods: a) placing a capsule in a vacuum chamber and pressing the powder under 11 atmospheres of vacuum, and b) placing powder in a sub-vacuum chamber, evacuating it, and pressing the powder in advance. There is a method of filling the capsule in a vacuum.

However, for the measure a), since the powder is filled into the capsule and then evacuated, the problem i) still remains. Furthermore, with respect to the measure b), when the powder in the subchamber is evacuated, the problem j) above remains.

In addition, both a) and b) rain countermeasures require a vacuum chamber and the entire inside of the vacuum chamber must be evacuated, resulting in a time loss.

(Problems to be Solved by the Invention) In view of the problems of the prior art described above, the present invention provides a method for easily deaerating the inside of a capsule and efficiently filling the deaerated capsule with raw material powder, and It is an object of the present invention to provide an apparatus for carrying out the method.

(Means for Solving Problems According to the Invention) A step of deaerating the powder raw material in a powder storage container equipped with a weir having a large number of openings inside which does not allow powder to pass through when not vibrating, and simultaneously with the step, a capsule body. After both the powder storage container and the capsule body reach a high degree of vacuum, the powder storage container is vibrated to transfer the powder raw material accumulated inside the capsule body into the capsule body. A method for vacuum filling powder into capsules for HIP treatment was constructed in the step of sealing the capsule.

In addition, there is a powder storage container equipped with a weir having a large number of openings that do not allow powder to pass through when the vibration is not applied, and a degassing pipe that passes through a vacuum pump. a two-pronged degassing pipe, which is connected to the two through valves, and whose lower end is connectable to a degassing pipe provided on the top cover of the capsule body;
A vacuum filling device for powder into a capsule for HIP processing was constructed with a jig for sealing the degassing tube of the capsule body.

Furthermore, the weir is shaped like an inverted truncated cone with an upward opening, and has a slanted upper lid at the top, and the numerous openings provided in the weir face diagonally upward.
In addition, it is tapered inward to prevent powder from flowing into the interior in a non-vibration state.

(Example) An explanation will be given based on FIG. 1. 1 is the capsule body. 2
3 is a capsule upper lid, and 3 is a deaeration pipe provided at the center of the capsule upper M2. Reference numeral 4 denotes raw material powder to be filled into the capsule body 1, which is supplied via a degassing pipe 8. The deaeration pipe 3 and the deaeration pipe 8 are connected by a rubber pipe 6. 5 is a degassing tube sealing jig. Reference numeral 7 denotes a branch degassing pipe branched from the degassing pipe 8, which is connected to a vacuum pump (not shown) via a valve 10.

A powder storage container 13 is provided in the upper part of the deaeration pipe 8 via a valve 11, and the container 13 further communicates with the deaeration pipe 9 through a valve 12 to a vacuum pump.

Reference numeral 14 denotes a weir having a large number of openings 15, and is in the shape of an inverted truncated cone that opens upward. A sloped upper lid 16 is provided at the top of the weir 14, and the powder supplied from above is passed through this sloped upper lid 1.
6 and is distributed laterally and accumulates between the weir 14 and the container 13.

As shown in FIG. 2, the opening IS provided in the weir 14 is bored diagonally upward toward the center and tapered inward.
The diameter and inclination are such that powder will not flow into the weir 14 unless vibration is applied.

Although not shown, the container 13 is provided with a vibration device, and when the container 13 is vibrated by the vibration device, powder flows in small amounts through the openings 15 of the weir 14.

(Function) Powder 4 is put into powder storage container 13. At this time, valve 11 is closed. Next, the valve 12 is opened and the inside of the container 13 is evacuated. At the same time, vibration is applied to the container 13. Then, the powder continuously flows into the weir 14 little by little from the opening 15 of the weir 14.
flow inside. At this time, even if the degree of vacuum of the powder 4 in the container 13 is poor, the degree of vacuum is increased when it passes through the opening 15 of the weir 14.

In parallel with the above operation, open the valve 10, and then open the capsule body 1.
When the inside of the container 13 and the inside of the capsule body 1 reach a predetermined degree of vacuum, the valves 10 and 12 are closed.

Next, the valve 11 is opened, and the powder 4 is dropped from the weir 14 into the capsule body 1 to be filled. After the powder 4 is vacuum-filled into the capsule body 1, the degassing tube 3 is sealed with a sealing jig 5 and subjected to the next HIP process.

(Effect) L1I equipped with a large number of openings 15 in the powder storage container 13
14 is provided and the container 13 is evacuated and vibration is also applied, so that the powder continuously falls into the capsule little by little from the flowering. During this falling, the degree of vacuum of the powder increases, and vacuum filling into the capsule is ideally performed.

In particular, the aperture 15 provided in the weir has a diameter and slope that prevents powder from flowing into the capsule unless vibration is applied, so that powder with insufficient vacuum will not flow into the capsule, allowing the powder to fall. The adsorbed gas inside is completely removed and a high quality sintered body can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of an apparatus for implementing the method of the present invention. FIG. 2 is an enlarged view of the section viewed from arrow A in FIG. FIGS. 3(a) to 3(c) are explanatory diagrams of the conventional method. In the figure; 1 Capsule body 3 Deaeration pipe 5. Degassing pipe sealing jig 7 Deaeration pipe 9 Deaeration pipe 11 Valve 13 Container for powder storage 15 Opening capsule top lid Raw material powder rubber tube Deaeration tube valve valve weir Slanted top lid that's all Applicant: Sumitomo Heavy Industries, Ltd. Sub-Agent Patent Attorney Isamu Ohashi Figure 3 (C)

Claims (1)

[Scope of Claims] 1) A step of deaerating the powder raw material in a powder storage container equipped with an internal weir having a large number of openings that do not allow powder to pass through during non-vibration, and a capsule body at the same time as this step. After both the powder storage container and the capsule body reach a high degree of vacuum, the powder storage container is vibrated to transfer the powder raw material accumulated in the weir into the capsule body, and the capsule body is degassed. 1. A method for vacuum filling powder into capsules for HIP processing, the method comprising: 2) A powder storage container that is equipped with a weir inside which has a large number of openings that do not allow powder to pass through when no vibration is applied, and a degassing pipe that passes through a vacuum pump; A HIP process characterized by comprising a bifurcated deaeration pipe which is connected to a pump through a valve and whose lower end can be connected to a deaeration pipe provided on the upper lid of the capsule body, and a jig for sealing the deaeration pipe of the capsule body. Vacuum filling equipment for powder into capsules. 3) The weir is in the shape of an inverted truncated cone that opens upward, has a sloping upper lid, and the numerous openings provided in the weir face diagonally upward and taper inward. The vacuum filling device for powder into capsules for HIP treatment according to claim 2).