JPH0335597B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hot isostatic press apparatus that stores a workpiece in a heating furnace inside a high-pressure container and processes the workpiece under high temperature and high pressure.

The hot isostatic press equipment (HIP equipment) stores the workpiece in a heating furnace built into a high-pressure container, and heats the inert gas such as argon gas sealed inside to high temperature and high pressure. The heating furnace has a space surrounded by a heat insulating layer, that is, a furnace chamber. However, in order to improve the thermal efficiency inside the furnace, the heat insulating layer is made of a material that has particularly excellent heat resistance and insulation performance, and the temperature inside the furnace can now be raised to about 2000 degrees Celsius and about 2000 atmospheres. At the same time, the processed product after hot isostatic pressing is heated at 100 to 150℃ in the furnace.
It is necessary to cool down the material to a certain degree before taking it out, and it takes a long time to cool down the inside of the furnace, which is surrounded and defined by a heat insulating layer. Therefore, conventionally, a cooling means for forcibly circulating a refrigerant within the furnace has been employed in order to actively lower the temperature inside the furnace.

However, in the conventional cooling method using forced circulation, it is difficult to flow the refrigerant into every corner of the triple structure consisting of a high-pressure container, a heat insulating layer, and a heating mechanism, and a satisfactory cooling effect cannot be obtained. However, this method requires a complicated forced circulation device, which increases the size of the entire device.

The present invention was developed in order to eliminate the above-mentioned drawbacks of the heating furnace of the conventional hot isostatic press apparatus, and is a hot isostatic press equipped with a heating furnace with a built-in heating mechanism inside a high-pressure container. In a hydraulic press device, an air inlet passage having an intake check valve is provided on the lower side of the heating furnace defined by a heat insulating layer, and the air is passed from the exhaust check valve at the upper part of the furnace through a flow path in the heat insulating layer to the lower end. It is characterized by the fact that it is equipped with a cooling mechanism that has an in-furnace gas exhaust path that connects to the flow path outside the heat insulating layer through a side exhaust check valve. An object of the present invention is to provide a heating furnace for a hot isostatic press apparatus that can efficiently cool a heating furnace inside a high-pressure container by incorporating the above.

The present invention has the above-mentioned structure, and when the pressure inside the flow path outside the heat insulation layer is reduced upon completion of the hot isostatic pressing process, the reduced pressure opens the exhaust check valve and reaches the flow path inside the heat insulation layer, and is then used for exhaust. As the check valve is opened and the gas reaches the furnace chamber, the high-temperature, high-pressure gas in the furnace chamber is cooled and discharged through the flow path inside the insulation layer and the flow path outside the insulation layer. As the inside of the flow path outside the heat insulating layer is cooled, the intake check valve opens due to the relative negative pressure inside the furnace chamber, and the gas inside the furnace is replaced by low-temperature gas flowing in from the intake air path, thereby achieving the above-mentioned pressure reduction and increase. By repeating pressure (injection of low-temperature gas), the entire interior of the high-pressure vessel, including the furnace chamber, can be efficiently cooled in a short time, and the hot isostatic press processing capacity can be significantly improved by shortening the cycle time. .

Furthermore, in the present invention, since the discharged high-temperature and high-pressure furnace gas is cooled while flowing through the heat insulating layer inner flow path and the heat insulating layer outer flow path of the cooling mechanism, the air intake and exhaust ports of the high pressure vessel, It is possible to prevent heat damage to the intake and exhaust pipe on-off valves, etc. that are connected in series, and to significantly increase their durability.It is also possible to reduce the time required to fill inert gas for processing by filling the flow path in the heat insulating layer with low-temperature gas. It has advantages such as miniaturization of the device by incorporating a cooling mechanism with a short and simple structure into the compact interior of the heating furnace.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. An embodiment of the present invention is shown in FIGS. 1 and 2,
In the figure, 1 is the high-pressure container main body, 2 is the bottom lid with a seal ring 2a, and 3 is the top lid with a seal ring 3a. A bottom cover 3 and a top cover 2 are placed on the top and bottom of the high-pressure vessel body 1.
As shown in the diagram, the containers are tightly sealed to form a closed high-pressure container with a structure that can withstand high temperatures and pressures.

Further, on the upper side of the bottom lid 2, upper and lower members 4a,
A hearth 5 made of a heat insulating material is disposed via a support member 4 having a support member 4b.
A cylindrical heat insulating layer 10 having an upper surface is placed at an appropriate distance around the periphery of the high-pressure vessel. Furnace chamber A surrounded and defined
A hermetically sealed heating furnace with , and has a structure in which hot isostatic pressing can be applied to the housed workpieces (not shown) under high pressure.

Furthermore, the heat insulating layer 10 includes an inner heat insulating layer 10
a. Consisting of an outer heat insulating layer 10b and an exterior plate 11, a flow path B within the heat insulating layer extending from the top surface to the lower side is provided between the inner heat insulating layer 10a and the outer heat insulating layer 10b, and the inner and outer heat insulating layers A cover ring 13 inserted into the protruding lower end 11a of the exterior plate 11 is disposed on the lower end sides of the exterior plates 10a and 10b, and the lower end 11a of the exterior plate 11 is removably fitted into the support member 4. The heat insulating layer 10 has hanging tools 14,
It is suspended by the upper lid 3 via the upper lid 3 and can be stored in and taken out from the high-pressure container together with the upper lid 3.

Furthermore, on the lower side of the heating furnace, there is an inlet check valve 15 that is attached to the lower member 4b of the support member 4 and that allows air to flow only to the furnace chamber A side, and an upper member 4 of the heating furnace.
an air inlet passage consisting of an air inlet hole 16 extending through the hearth 5, and an inner heat insulating layer 10 at the upper part of the furnace.
A is provided with an exhaust check valve 17 that communicates with the flow path B in the heat insulating layer and allows flow only to the flow path side,
A spiral channel 13a for cooling is provided on the outer peripheral surface of the cover ring 13 and communicates with the lower end of the channel B in the heat insulating layer. Upper and lower members 4a, 4
A cooling pipe 18 with fins is disposed in the cooling chamber D between the space D and reaches the lower end 11a of the exterior plate 11.
A discharge check valve 19 is provided which can flow only to the side of the flow path C outside the heat insulating layer between the high pressure container main body 1 and the high pressure container body 1,
A cooling flow path consisting of an exhaust check valve 17, a heat insulating layer inner flow path B, a spiral flow path 13a, and a cooling pipe 18;
The exhaust check valve 19 and the flow path C outside the heat insulating layer constitute a furnace gas exhaust path.

Further, an intake/exhaust port 20 is provided in the upper part of the high-pressure container, that is, the upper lid 3, and an intake/exhaust pipe 21 having an on-off valve 22 is connected to the intake/exhaust port 20.
Bottom cover 2 serving as the intake side of the intake check valve 15
Entrance space E between the lower member 4b of the support member 4
The air is communicated with the lower part of the flow path C outside the heat insulating layer through an opening (not shown) provided in the lower end 11a of the exterior plate 11, and further, air flows in from the inlet side space E via the intake check valve 15. The cooled low-temperature gas flows through the cooling chamber D in the support member 4 and into the furnace chamber A through the air inlet hole 16.

Note that 30 in FIG. 1 is a sealing member between the lower end of the inner heat insulating layer 10a and the lower end 11a of the exterior plate 11 and the cover ring 13.

The illustrated embodiment has the above-mentioned configuration, so the upper cover 3 is removed from the high-pressure container body 1 and the heat insulating layer 1 is removed.
0, the furnace chamber A in the high-pressure vessel main body 1 can be opened, and the products to be processed are placed on the hearth 5 and accommodated. Then, as shown in the figure, a heat insulating layer 10 is placed inside the high-pressure vessel main body 1, an upper lid 3 is fitted, and an appropriate mechanism (not shown) is used to supply a processing inert gas such as argon gas to the inside and outside of the heating furnace inside the high-pressure vessel. Pressurize gas,
By enclosing the inert gas in the furnace chamber A at high temperature and high pressure using the heater 6, the workpiece (not shown) on the hearth 5 is subjected to hot isostatic pressing, that is, powder sintering, etc. It is possible to perform molding processing.

If the item to be processed is taken out immediately after the processing is finished, extremely high-temperature and high-pressure gas inside the furnace will blow out, making it difficult and dangerous to handle the high-temperature item. Container must be opened. In the embodiment described above, when the hot isostatic pressing process is completed, the on-off valve 22 is opened to exhaust the inside of the flow path C outside the heat insulating layer to reduce the pressure, and the reduced pressure opens the exhaust check valve 19 to open the cooling pipe 18 and the spiral stream. The passage 13a reaches the passage B in the heat insulating layer, and the exhaust check valve 17 is opened, and the high-temperature, high-pressure furnace gas in the furnace chamber A flows from the exhaust check valve 17 through the furnace gas discharge passage and is insulated. Extralayer flow path C
The air is discharged from the intake/exhaust port 20 and the intake/exhaust pipe 21 .

After the hot isostatic pressing process is completed, the inside of the high-pressure container has the highest temperature in the furnace chamber A, and the inside of the heat insulating layer flow path B, the spiral flow path 13a, the cooling pipe 18, and the flow path outside the heat insulating layer C side. Since the temperature is relatively low, the high-temperature and high-pressure furnace gas in the furnace chamber A is cooled during the discharge, and thermal damage to the intake and exhaust ports 20, intake and exhaust pipes 21, on-off valves 22, etc. is significantly reduced. Their durability is increased.

Next, after the pressure reduction, low temperature gas is pressurized into the flow path C outside the heat insulating layer from the intake/exhaust pipe 21 and the intake/exhaust port 20 and pressurized. The low-temperature gas cools the flow path C and flows into the inlet side space E of the inlet check valve 15, so that it is cooled from the inlet check valve 15, which is opened in conjunction with the pressure reduction in the furnace chamber A. It flows into the chamber D and further flows into the furnace chamber A from the air inlet 16 to be replaced with the furnace gas.

By repeating the depressurization and pressurization (low-temperature gas injection) on the side of the flow path C outside the heat insulating layer, the entire area inside the high-pressure container including the inside of the heating furnace can be efficiently cooled and depressurized. The pressure characteristics P and temperature characteristics T as shown in FIG. 2 are obtained, and the temperature drop progresses smoothly, resulting in efficient cooling and pressure reduction at the same time.

Furthermore, when filling inert gas for generating high-temperature, high-pressure gas to be used for processing new objects to be processed after the cooling is finished, low-temperature gas is filled in the flow path B in the heat insulating layer. The time required for encapsulation is shortened, and the time required for cooling is shortened.
Processing cycle time is shortened and throughput is significantly improved.

Furthermore, the cooling mechanism of the present invention has a simple structure and is compactly incorporated into the heating furnace, making the device excellent in durability, reliability, and compactness.

Although the present invention has been described above with reference to embodiments, it goes without saying that the present invention is not limited to such embodiments, and that various design modifications can be made without departing from the spirit of the present invention. .

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a hot isostatic pressing apparatus showing an embodiment of the present invention, and FIG. 2 is a characteristic diagram of temperature and pressure in the embodiment shown in FIG. 1: High pressure container body, 2: Bottom lid, 3: Top lid, 6:
heating mechanism (heater), 10: heat insulation layer, 15: intake check valve, 16: intake hole, 17: exhaust check valve, 19: discharge check valve,
A: Furnace chamber, B: Channel inside the heat insulating layer, C: Channel outside the heat insulating layer.

Claims (1)

[Claims] 1. In a hot isostatic press device equipped with a heating furnace with a built-in heating mechanism in a high-pressure container, an air intake path having an air intake check valve is provided on the lower side of the heating furnace defined by a heat insulating layer. The cooling mechanism is equipped with an in-furnace gas discharge passage that runs from an exhaust check valve at the top of the furnace, through a passage within the insulation layer, through a discharge check valve at the bottom end to a passage outside the insulation layer. Heating furnace of hot isostatic press equipment.