JP2843471B2 - Airtight structure of partition door in vacuum processing furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an airtight structure of a partition door in a vacuum processing furnace.

[0002]

2. Description of the Related Art Conventionally, in a tunnel-type vacuum processing furnace, a furnace body is divided into a plurality of zones, and in a process of moving an object to be processed, the furnace body is charged into a vacuum atmosphere from under atmospheric pressure, and then is moved from the vacuum atmosphere to Since it is discharged to the atmospheric pressure, it is partitioned by providing a partition door which can be opened and closed for each furnace zone, and the joining surface between the partition door and the end of the furnace zone has an airtight structure (Japanese Patent Laid-Open No. No. 62-116890).

[0003] The airtight structure of this type of partition door is such that the joint surface between the partition door and the end of the furnace zone is made airtight by being brought into close contact with each other by negative pressure in each zone, so that the degree of vacuum in each zone can be maintained. Have been.

[0004]

In the case where the vacuum processing furnace is a vacuum dezincing furnace which heats galvanized steel scrap under vacuum to evaporate zinc on the surface of the steel scrap to separate the steel scrap into zinc. In addition, evaporating zinc invades the airtight structure of the partition door, hinders the airtight function, makes opening and closing the partition smooth, and lowers the degree of vacuum maintenance, thereby hindering the dezincing operation as described above. There is a risk of giving.

The present invention has been made to solve the above-mentioned problems of the prior art, and the peripheral edge of the partition door is brought into contact with the airtight structure at the end of the furnace zone and gas is blown out. It is an object of the present invention to provide an airtight structure of a partition door in a vacuum processing furnace, which can prevent diffusion and invasion of evaporated zinc, can smoothly open and close the partition door, and can effectively prevent a decrease in the degree of vacuum maintenance.

[0006]

In order to achieve the above object, according to the present invention, an openable and closable partition door for dividing a tunnel type vacuum processing furnace into a plurality of zones is provided in a shut-off chamber, and a peripheral edge of the partition door is provided. The part is characterized by being brought into contact with an airtight structure provided at the end of the furnace zone and having an annular member for ejecting gas.

[0007]

In this way, the vacuum processing furnace is a vacuum dezincing furnace, which heats galvanized steel scrap under vacuum to evaporate the zinc on the steel scrap surface and separate it into steel scrap and zinc. The peripheral edge of the partition door is in contact with the airtight structure at the end of the furnace zone, and the gas is blown out and introduced into the furnace to prevent the zinc from evaporating from the furnace. The opening and closing of the partition door can be smoothly performed, and the predetermined degree of vacuum can be effectively maintained.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an overall structural view of a vacuum processing furnace, and FIG.
1 is a sectional view of FIG. 1, FIG. 3 is a vertical sectional view of an airtight structure of a partition door showing one embodiment of the present invention, and FIG. 4 is an enlarged horizontal sectional view of a main part of the airtight structure.

1 to 4, reference numeral 10 denotes a tunnel type vacuum processing furnace, for example, a vacuum dezincing furnace. The vacuum processing furnace 10 has a circular cross-section, and according to the moving direction of the basket 32 containing the galvanized steel sheet waste, the charging zone 12, the charging shutoff chamber 18, the dezincing zone 14, the discharge shutoff chamber 20, the discharge zone. 16 and the like are arranged in the longitudinal direction.

A plurality of rotating rollers 34 are provided in the longitudinal direction through the furnace wall 78 of the vacuum processing furnace 10. Both ends of the rotating roller 34 are supported by bearings, and a sprocket 37 is attached to the end of the roller and connected to a driving source 35 to rotate the rotating roller to move the basket 32 intermittently. Inside the vacuum processing furnace 10, heating means 40 and 42, for example, a plurality of heating elements are arranged on the floor and on both sides. In the charging zone 12 and the dezincing zone 14, a uniform high-temperature atmosphere of a predetermined temperature is maintained, respectively. Further, the inside of the vacuum processing furnace 10 is maintained at a predetermined degree of vacuum, is connected to a vacuum system 68 via a pipe 70, and 72 indicates an exhaust pipe. A zinc recovery chamber 46 is connected below the vacuum processing furnace 10 via an introduction path 48, and one end of the pipe 70 is opened to the zinc recovery chamber 46, and the inside of the zinc recovery chamber 46 is also opened. It is maintained at a predetermined degree of vacuum.

As described above, in the vacuum processing furnace 10, the basket 32 containing the steel sheet waste is inserted from the charging zone 12 with the operation of the rotating roller 34, intermittently through the dezincing zone 14 to the discharging zone 16. And discharged out of the furnace 10. In the movement process, the dezincing zone 14 is always maintained at a predetermined degree of vacuum, and in the charging zone 12, the internal pressure is at the atmospheric pressure when the basket 32 is loaded. From the time of completion, the partition door 22,
24 is closed and communicated with the pipeline 70 of the vacuum system 68 to start evacuation of the inside and reduce the pressure to a predetermined pressure. Next, the partition door 24 and the partition door 26 at the end of the dezincing zone 14 are opened, and the basket 32 is moved to the dezincing zone 1.
4, the partitioning doors 24 and 26 are closed and the pipeline 70 is also closed, and the pressure relief valve (not shown) provided in the charging band 12 is opened, so that the inside of the charging band 12 becomes large. The pressure returns to the atmospheric pressure, the partition door 22 is opened, and the next basket 32 is opened.
Will be charged. Then, in the discharge zone 16, the operation reverse to the operation in the charging zone 12 is performed.
When the basket 32 is not located at 6, that is, when the basket 32 is located at the charging band 12, the partition doors 28 and 30 are closed, and the inside is depressurized to a predetermined degree of vacuum. .

After the dezincing step, the basket 32 is moved into the discharge zone 16, and subsequently, the partition door 28 is closed and the partition door 30 is opened, and the inside of the discharge zone 12 is restored to the atmospheric pressure. , Basket 32 is vacuum processing furnace 10
It is extracted outside and moved to the next step.

The partitioning doors 24 and 26 are provided in the charging / blocking chamber 18 and the partitioning door 28 is provided in the discharge / blocking chamber 20, respectively.

In the process of moving the basket 32 containing the steel scrap in the dezincing zone 14, the steel scrap is heated in a high-temperature atmosphere under reduced pressure using the heating means 40 and 42 as heat sources, and reaches a predetermined temperature. When the temperature rises, the zinc on the surface of the steel scrap evaporates, generating zinc vapor molecules. Then, the evaporated molecules of zinc that have moved into the gas phase flow in the dezincing zone 14 together with the gas, pass through the introduction path 48, flow into the zinc recovery chamber 46, collide with the recovery box 50, and remove the evaporated molecules. After collection, the gas is exhausted by a vacuum system 68 via line 70.

The inner wall surface of the zinc recovery chamber 46 is provided with a cooling surface 52 formed of a cooling jacket through which a coolant is circulated, so that a low-temperature atmosphere is set, and the surface temperature of the recovery box 50 is set to a temperature lower than the melting point of zinc. ing. The vaporized molecules start to coagulate in the collection box 50, and after a required coagulation time, the coagulation is completed.

FIG. 3 shows partition doors 24 and 26 provided in the charging shutoff chamber 18.
And 28 will be described.

The furnace wall structure of the dezincing zone 14 of the vacuum processing furnace 10 has a furnace shell 77 on the outer periphery and a heat insulating wall 78 on the inner side, and is sufficiently insulated from the high temperature atmosphere in the furnace. It is trying to reduce heat dissipation. The furnace end of the dezincing zone 14 is opened in a rectangular hole shape so that the basket 32 can be moved into the zone. Reference numeral 80 denotes an end plate at the periphery of the opening of the furnace zone end 103. Airtight means for maintaining the degree of vacuum in the vacuum processing furnace 10 is formed between the inner surface of the partition door 26 and the outer surface of the furnace zone end 103.

The door body 50 of the partitioning door 26 has a furnace end opening 79.
It is made to close, is formed using heat insulating material and the like,
The periphery is surrounded by a cooling box 102 through which the coolant flows. The cooling box 102 is provided with the corresponding plate 54 on the side surface of the end plate 80, and the rear surface of the door body 50 is provided with a cooling jacket 56 through which a coolant flows.
The partition door 26 is protected from cooling. Further, a guide member 58 having an L-shaped cross section is provided on the outer periphery of the cooling box 102.
Are arranged.

An airtight structure 104 supported by an end plate 80 is disposed at the end of the dezincing zone 14, that is, at the furnace zone end 103 around the furnace end opening 79 so as to face the cooling box 102. ing.

The airtight structure 104 is provided with an inner annular member 110 and an outer annular member 112, and each of the annular members 11 is provided.
It is attached by the side wall 81 of the cooling box 82 through which the coolant provided as a part of the end plate 80 between 0,112 flows.

The sealing material 7 is provided at an intermediate portion of the side wall 81.
4 are attached by holding members 76 on both sides,
The tip of 4 is made to contact the surface of the contact plate 54. Each of the inner annular member 110 and the outer annular member 112 is formed in a flow path of a gas, for example, N ₂ gas, and is connected to a gas system from outside, and a seal is provided on a wall surface of each of the annular members 110 and 112. As shown by arrows A and B, the injection port 114 of the gas introduced into the dezincing zone 14 and the injection port 116 of the airtight fluid introduced into the charging shutoff chamber 18 are opened. The sealing member 74 is preferably made of an elastic material, for example, nitrile rubber or fluorine rubber, and is cooled and protected by the side wall 81 of the cooling box 82.

By using such airtight means,
In dezincing the galvanized steel sheet waste in the vacuum processing furnace 10, it is possible to prevent zinc from evaporating in the dezincing zone 14 from entering the space between the partition door 26 and the furnace zone end 79 from inside the furnace. Also, when the partition door 26 is opened, the charging belt 12 is opened.
It is possible to avoid the deterioration of the sealing performance due to the vaporized zinc and dust generated in the sealing member 74 due to the above-mentioned gas jetting.
It is possible to suppress the diffusion and invasion of zinc vapor into the fuel cell.

As another embodiment, the cooling box 1 of the partition door 26 is used.
By arranging another hermetic structure in the vicinity of 02, it is possible to avoid that the evaporated performance of zinc or dust adheres to the surface of the aforesaid plate 54 to deteriorate the sealing performance.
Diffusion and invasion of the evaporated zinc from the dezincing zone 14 can be suppressed.

Next, in order to raise and lower the partitioning door 26 so that it can be opened and closed, a clamp member 60 is provided in the charging / discharging chamber 18, and a fixture 62 engaged with the clamp member 60 is located near the cooling box 102. Is attached to the attachment member 64 provided in the first embodiment. Then, by the rotation of the clamp member 60, the partition door 26 is separated from the airtight structure portion 104 and is moved backward on the roller 96 as shown by the dotted line.

Since the partitioning door 26 is moved, a part of the rotary roller 34 provided in the charging / discharging chamber 18 is moved from a position shown by a dotted line to a solid line by a rotating means (not shown). Is rotated to the position indicated by, the interval between the rotating rollers 34 is enlarged, and the lifting and lowering of the partition door 26 can be facilitated.

A heat-insulating plate 84 is connected to the elevating means 86 on the side of the airtight structure 104 inside the charging / discharging chamber 18 so as to be able to move up and down using the elevating means 86.

A hoist 88 for opening and closing the partition door 24 is provided via a chain 90, and a hoist 92 for opening and closing the partition 26 is provided via a chain 94. 24, 26 and a hoist 88,
Reference numerals 92 are operated using hoisting means (not shown).

When the partition door 26 is raised for opening, it is separated from the airtight structure 104, and the heat-insulating plate 84 is lowered by using the lifting / lowering means 86.
The surface of the airtight structure 104 is shielded, so that the airtight structure 104, particularly the sealant 74, is sufficiently protected against radiation from the high-temperature atmosphere in the dezincing zone 14.

[0030]

As described above, according to the present invention,
The vacuum processing furnace is a vacuum dezincing furnace, in which galvanized steel sheet waste is heated under vacuum to evaporate the zinc on the surface of the steel sheet waste and separate it into steel sheet waste and zinc. While being in contact with the airtight structure at the end of the band, the gas is ejected as a high-speed airflow and introduced into the furnace to prevent the diffusion and invasion of zinc vapor from inside the furnace. A great effect is achieved, for example, the smoothness can be maintained and a predetermined degree of vacuum can be effectively maintained.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a vacuum processing furnace.

FIG. 2 is a sectional view of FIG.

FIG. 3 is a longitudinal sectional view of an airtight structure of a partition door showing one embodiment of the present invention.

FIG. 4 is an enlarged horizontal sectional view of a main part of the airtight structure.

[Explanation of symbols]

 10 Vacuum processing furnace 26 Partition door 82, 102 Cooling box 104 Airtight structure 110 Inner annular member 112 Outer annular member

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Mitsuo Ijuin 1780 Kamikono, Yachiyo-shi, Chiba Kawasaki Heavy Industries, Ltd. Inside the Yachiyo Plant (72) Inventor Takehiko Inoue 1780, Kamikono, Yachiyo-shi, Chiba Kawasaki Heavy Industries Yachiyo Plant (72) Inventor Yuji Okada 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Shunichi Fujio 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Kazuhiro Suzuki 3-33 Konosu-cho, Toyota City, Aichi Prefecture Toyokin Co., Ltd. (72) Inventor Yoshiyoshi Nakatani 2-4-7 Kyomachibori, Nishi-ku, Osaka-shi, Osaka Chugai Reactor Industry Co., Ltd. (72) Inventor Tanaka Takashi 2-57 Kyomachibori, Nishi-ku, Osaka-shi, Osaka Inside Chugai Furnace Industry Co., Ltd. (56) References 169174 (JP, A) Jikken 63-39243 (JP, Y2) (58) Fields investigated (Int. Cl. ⁶ , DB name) F27D 7/00-7/06 F27D 1/18 F27B 9/02- 9/04

Claims (4)

(57) [Claims] An openable and closable partitioning door for dividing a vacuum processing furnace of a tunnel type into a plurality of zones is provided in a shut-off chamber, and a peripheral portion of the partitioning door is provided at an end of the furnace zone and is formed of an annular member for ejecting gas. An airtight structure of a partition door in a vacuum processing furnace, the airtight structure being in contact with an airtight structure having the airtight structure. 2. An airtight structure of a partition door in a vacuum processing furnace according to claim 1, wherein an annular member for ejecting gas is provided at an end of the furnace zone facing a peripheral portion of the partition door. . 3. The partitioning door of a vacuum processing furnace according to claim 1, wherein the airtight structure has a double annular member, and a cooling box is provided between each annular member. Airtight structure. 4. The airtight structure of a partition door in a vacuum processing furnace according to claim 1, wherein a cooling box is provided at a peripheral portion of the partition door.