JPH11173428A - Sealing device for flange - Google Patents

Sealing device for flange

Info

Publication number
JPH11173428A
JPH11173428A JP33879897A JP33879897A JPH11173428A JP H11173428 A JPH11173428 A JP H11173428A JP 33879897 A JP33879897 A JP 33879897A JP 33879897 A JP33879897 A JP 33879897A JP H11173428 A JPH11173428 A JP H11173428A
Authority
JP
Japan
Prior art keywords
flange
seal
face
seal face
gas
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP33879897A
Other languages
Japanese (ja)
Inventor
Mitsuhiro Yamanaka
光弘 山中
Masayuki Watabe
雅之 渡部
Masahiro Kawakami
正弘 川上
Takeshi Sekiguchi
関口  毅
Norihiko Taguchi
憲彦 田口
Katsuhiro Iwasaki
克博 岩崎
Shinichi Isozaki
進市 磯崎
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JFE Engineering Corp
Original Assignee
NKK Corp
Nippon Kokan Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NKK Corp, Nippon Kokan Ltd filed Critical NKK Corp
Priority to JP33879897A priority Critical patent/JPH11173428A/en
Priority to CN98810337A priority patent/CN1276862A/en
Priority to KR1020007003164A priority patent/KR100339261B1/en
Priority to PCT/JP1998/004703 priority patent/WO1999020966A1/en
Priority to AU94629/98A priority patent/AU751764B2/en
Priority to CA002307090A priority patent/CA2307090C/en
Priority to TW87117290A priority patent/TW434318B/en
Publication of JPH11173428A publication Critical patent/JPH11173428A/en
Pending legal-status Critical Current

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  • Sealing Devices (AREA)
  • Furnace Details (AREA)

Abstract

PROBLEM TO BE SOLVED: To correct the deformation of a flange by providing two or more sealing members holding air-tightness between a seal face member attached to seal faces of a pair of flanges in a furnace or the like in such a manner that it is replaceable and air-tight and a seal face of opposing flange in the radial direction of the flange on the seal face member and the seal face of the opposing flange. SOLUTION: In a large bore flange for furnace body, a seal face member 5 is attached to a seal face of an upper face flange 2 so as to be replaceable, and a packing 9 is interposed between a rear surface of the seal face member 5 and the upper face flange 2 to keep air-tightness between the seal face member 5 and the upper face flange 2. Moreover, expansion type seals 3, 3 are interposed at an interval between the seal face member 5 and a seal face of a lower face flange 1. As for this expansion type seal 3, it has a tube shape in which gas can be introduced, its horizontal displacement is bound by a pressing member 4 provided on the lower face flange 1, and air for expansion is supplied through a gas path for expanding seal 7 formed inside the lower face flange 1.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、炉、圧力容器等に
おけるフランジのシール装置の改良に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a flange sealing device for a furnace, a pressure vessel, and the like.

【0002】[0002]

【従来の技術】従来のフランジのシール装置として、図
4(a) に示すように締結ボルトの内側のシール面に金属
製または非金属性のパッキン(例えば、Oリング、ノン
アスベストガスケット、チューブシール等)をセットし
て締結ボルトの締め付け力でパッキンにある面圧を与え
てシールするもの、或いは同図(b) に示すように、パッ
キンを一対セットしてその間にパージガスを入れ、締結
ボルトの締め付け力で同様にシールを行うものがあり、
(b) の構造では、内側のシールとフランジとの間に隙間
が形成されて炉内のガスが漏れても、このガスは炉外に
出ず、パージガスが炉内に入るようになっている。
2. Description of the Related Art As a conventional flange sealing device, as shown in FIG. 4 (a), a metal or non-metal packing (for example, an O-ring, a non-asbestos gasket, a tube seal) is provided on a sealing surface inside a fastening bolt. Etc.) and set the seal by applying a certain surface pressure to the packing with the tightening force of the fastening bolt, or as shown in FIG. Some seals are similarly made with the tightening force.
In the structure of (b), even if a gap is formed between the inner seal and the flange and gas in the furnace leaks, this gas does not go out of the furnace and the purge gas enters the furnace. .

【0003】[0003]

【発明が解決しようとする課題】しかし、これら従来の
ものは、フランジの開け、閉めを頻繁に行い、しかもフ
ランジが変形したりフランジシール面に傷が入ったりす
るとシールが困難になる。この場合、フランジを交換し
なければシール性の確保はできない。小径フランジの場
合は交換も比較的容易であるが大口径の場合交換は非常
に困難である。
However, in these conventional devices, the flange is frequently opened and closed, and furthermore, the sealing becomes difficult if the flange is deformed or the flange sealing surface is damaged. In this case, the sealing performance cannot be ensured unless the flange is replaced. In the case of a small diameter flange, replacement is relatively easy, but in the case of a large diameter, replacement is very difficult.

【0004】また、上記従来のパッキングは、フランジ
が変形した場合などに必ずしも十分対応できるものでは
なく、その場合のシール性が十分とはいえない。本発明
は上記事情にかんがみてなされたもので、その目的とす
るところは、一対のフランジの少なくとも一方のシール
面を別部材として取替え可能とし、このことにより、フ
ランジの補修を容易にし、またフランジの変形に対する
矯正を行えるシール装置を提供するものである。更に、
膨張型シールを複数個使用し、それらの中間部にパージ
ガスを導入することによりシール性の向上を図ることが
できるシール装置を提供するものである。
Further, the above-mentioned conventional packing cannot always sufficiently cope with a case where the flange is deformed, and the sealing performance in that case is not sufficient. The present invention has been made in view of the above circumstances, and an object thereof is to make it possible to replace at least one sealing surface of a pair of flanges as a separate member, thereby facilitating repair of the flange, and It is intended to provide a sealing device capable of correcting the deformation of the seal. Furthermore,
An object of the present invention is to provide a sealing device that can improve the sealing performance by using a plurality of inflatable seals and introducing a purge gas into an intermediate portion thereof.

【0005】[0005]

【課題を解決するための手段】すなわち本発明は、
(1)一対のフランジの少なくとも一方のシール面に取
替え可能かつ気密にシール面部材を取付け、このシール
面部材とこれに対向するフランジのシール面又はシール
面部材との間に両者間を気密に保持する2以上のシール
部材をフランジの径方向に列設してなることを特徴とす
る、フランジのシール装置、(2)シール部材はチュー
ブシールで、このチューブシールにそれぞれシール膨張
用ガスを導入するガス経路が接続されている、(1)に
記載のフランジのシール装置、(3)シール部材をシー
ル面の所定位置に固定する押え部材と、二つのシール部
材と一対のフランジとの間に形成された空間内にパージ
ガスを導入するガス経路とを設けている、(1)又は
(2)に記載のフランジのシール装置である。
That is, the present invention provides:
(1) A seal face member is replaceably and hermetically attached to at least one of the seal faces of a pair of flanges, and between the seal face member and the seal face of the flange facing the seal face member or the seal face member, the air gap between them is airtight. A flange sealing device characterized in that two or more sealing members to be held are arranged in a row in the radial direction of the flange. (2) The sealing member is a tube seal, and a gas for expanding the seal is introduced into the tube seal. (3) a sealing device for fixing a sealing member at a predetermined position on a sealing surface, and a sealing member for fixing a sealing member at a predetermined position on a sealing surface, and a pair of flanges. The flange sealing device according to (1) or (2), wherein a gas path for introducing a purge gas is provided in the formed space.

【0006】[0006]

【発明の実施の形態】図1は本発明のシール装置の一実
施の形態を示し、例えば、炉内圧2[kgf/cm2] の炉体用
大口径フランジのシール例を示す。この装置は、下面フ
ランジ1(例えば外径寸法、φ12000 mm)と上面フラ
ンジ2との間をシールするもので、上面フランジ2のシ
ール面には、シール面部材5(例えば、断面寸法300 ×
30mm)が取り付けられている。このシール面部材5は、
ボルト11,11により上面フランジに取り替え可能に
取り付けられ、また、シール面部材の裏面と上面フラン
ジとの間にはパッキンが介装され、シール面部材と上面
フランジとの気密性を保持している。上面フランジのシ
ール面、すなわちシール面部材5と下面フランジ1のシ
ール面との間には、炉内側及び炉外側にそれぞれ膨張型
シール3,3(例えば、断面寸法40×40mm)が間隙を設
けて介装されている。膨張型シール3,3は、内部にガ
スを導入可能なチューブ形状をなし、下面フランジ1内
に形成したシール膨張用ガス経路7,7とそれぞれ接続
されている。これらガス経路は図示しないガス(通常は
空気)供給源と接続され、膨張型シールに膨張用空気を
供給し、その供給圧を調節して、両シール面の気密性を
維持するようになっている。これら膨張型シールの両側
にはそれぞれ押え部材4,4(例えば、断面寸法40×40
mm)が下面フランジに固定されて設けられ、膨張型シー
ルの横変位を拘束するようになっている。さらに下面フ
ランジにはパージガス導入経路8が形成され、その基端
は図示しない不活性ガス(通常は窒素ガス)供給源と接
続され、その先端は、膨張型シール間の押さえ部材を通
って前記膨張型シール3,3と上下シール面との間の空
間に開口している。そしてこの空隙に、パージ用窒素ガ
スを導入するようになっている。下面フランジの炉内側
には、上述したシール構造を囲うように遮蔽板10が取
り付けられ、これにより炉内の熱からシール構造を保護
するようになっている。また、上下フランジ1,2に
は、フランジ冷却用の冷却水水路12が形成されてい
る。なお、6は締結ボルト(例えば、M80 ×72本)用の
孔である。
FIG. 1 shows an embodiment of a sealing device according to the present invention. For example, a sealing example of a large diameter flange for a furnace body with a furnace pressure of 2 [kgf / cm 2 ] is shown. This device seals between a lower surface flange 1 (for example, outer diameter dimension, φ12000 mm) and an upper surface flange 2, and a sealing surface member 5 (for example, having a cross-sectional size of 300 ×) is provided on the sealing surface of the upper surface flange 2.
30mm) is attached. This sealing surface member 5
It is replaceably attached to the upper surface flange by bolts 11, and a packing is interposed between the back surface of the sealing surface member and the upper surface flange to maintain the airtightness between the sealing surface member and the upper surface flange. . Inflatable seals 3 and 3 (for example, 40 × 40 mm in cross section) are provided between the seal surface of the upper flange, that is, the seal surface member 5 and the seal surface of the lower flange 1 on the inside and outside of the furnace, respectively. Has been interposed. The inflatable seals 3, 3 each have a tube shape capable of introducing a gas therein, and are connected to seal inflatable gas paths 7, 7 formed in the lower surface flange 1. These gas paths are connected to a gas (usually air) supply source, not shown, to supply inflation air to the inflatable seal, and to adjust the supply pressure to maintain the airtightness of both seal surfaces. I have. Pressing members 4 and 4 (for example, a cross-sectional dimension of 40 × 40) are provided on both sides of these inflatable seals, respectively.
mm) is fixedly provided on the lower surface flange to restrain the lateral displacement of the inflatable seal. Further, a purge gas introduction path 8 is formed on the lower surface flange, the base end of which is connected to an inert gas (usually nitrogen gas) supply source (not shown), and the tip end of which is passed through a holding member between inflatable seals. It is open to the space between the mold seals 3, 3 and the upper and lower seal surfaces. Then, nitrogen gas for purging is introduced into this gap. A shield plate 10 is attached to the inside of the furnace at the lower flange so as to surround the above-described seal structure, thereby protecting the seal structure from heat inside the furnace. Further, cooling water channels 12 for cooling the flange are formed in the upper and lower flanges 1 and 2. Reference numeral 6 denotes a hole for a fastening bolt (for example, M80 × 72).

【0007】この装置では、押え部材4の上面とシール
面部材5を合わせ、下面フランジ1と上面フランジ2を
締結ボルトで締結した後、二つのNBR 製膨張型シール3
に圧力3[kgf/cm2 ] の膨張用空気を2個所のシール膨張
用ガス経路7より送り、膨張型シールを膨張させてシー
ル面部材5に押し付けることによりシールされる。ま
た、下面フランジ1に固定された押さえ部材の当り面も
膨張型シール3の膨張力によりシールされる。そして、
二つの膨張型シール3の中間部に2個所のパージガス導
入経路8より圧力2.5[kgf/cm2 ] の窒素ガスを導入し、
もしも炉内側の膨張側シール3のシールが保てなくなっ
た場合でも炉内のCO等の有毒ガスは外へ出ず、パージガ
ス(窒素ガス)が炉内に入るだけであり、炉外の安全性
は保たれる。また、炉内が高温雰囲気の場合にも遮蔽板
10により膨張型シール3への直接の放射熱を遮蔽で
き、冷却用水路12により膨張型シール3周囲の金物温
度を下げることで膨張型シール3の温度を耐熱温度( 例
えば、80℃) 以下に保つことができる。
In this apparatus, the upper surface of the pressing member 4 and the sealing surface member 5 are aligned, and the lower surface flange 1 and the upper surface flange 2 are fastened with fastening bolts.
Is supplied from two seal inflation gas paths 7 at a pressure of 3 [kgf / cm 2 ], and the inflatable seal is inflated and pressed against the seal face member 5 for sealing. Further, the contact surface of the pressing member fixed to the lower surface flange 1 is also sealed by the expansion force of the expansion type seal 3. And
Nitrogen gas having a pressure of 2.5 [kgf / cm 2 ] is introduced into the intermediate portion of the two inflatable seals 3 from two purge gas introduction paths 8.
Even if the seal of the expansion side seal 3 inside the furnace cannot be maintained, the toxic gas such as CO in the furnace does not go out and only the purge gas (nitrogen gas) enters the furnace, and the safety outside the furnace Is kept. Further, even when the inside of the furnace is in a high temperature atmosphere, the radiant heat directly to the inflatable seal 3 can be shielded by the shield plate 10, and the temperature of the metal around the inflatable seal 3 is reduced by the cooling water channel 12, whereby the inflatable seal 3 is cooled The temperature can be kept below the heat-resistant temperature (for example, 80 ° C.).

【0008】この構造では、図2のように下面フランジ
1と上面フランジ2の隙間が10mm程度以下ならば膨張型
シール3の膨張力でシールは可能であるが、フランジの
締結、開放を繰り返す内にフランジが変形し、その隙間
が10mmを超えるような場合には上面フランジ2とシール
面部材5の間にシール9を挿入したり、図3のようにフ
ランジの変形に合う別のシール面部材5と交換すればシ
ール性は保てる。また、フランジの締結、開放作業など
でシール当り面に傷をつけた場合にもシール面部材5だ
けを交換すればよい。
In this structure, if the gap between the lower surface flange 1 and the upper surface flange 2 is about 10 mm or less as shown in FIG. 2, the seal can be made by the expansion force of the expansion type seal 3, but the fastening and opening of the flange are repeated. In the case where the flange is deformed and the gap exceeds 10 mm, a seal 9 is inserted between the upper surface flange 2 and the seal surface member 5, or another seal surface member adapted to the deformation of the flange as shown in FIG. If it is replaced with 5, the sealing property can be maintained. Also, when the sealing surface is damaged by the fastening or opening work of the flange, only the sealing surface member 5 needs to be replaced.

【0009】[0009]

【発明の効果】以上のように本発明によれば、フランジ
のシール面を交換できるようにすることにより、フラン
ジの補修を容易にし、またフランジの変形に対する矯正
を可能として、シール性の維持を容易に行うことができ
る。また、フランジのシール部材に膨張型シールを複数
使用することにより、シール性が向上し、さらにパージ
ガスをシール部材間に導入することにより、たとえ気密
性が低下してもガス漏れによる危険を防止し、安全性が
向上するなど顕著な効果を発揮する。
As described above, according to the present invention, the repair of the flange can be facilitated by allowing the sealing surface of the flange to be exchanged, and the deformation of the flange can be corrected to maintain the sealing performance. It can be done easily. Also, by using a plurality of inflatable seals for the seal member of the flange, the sealing performance is improved, and by introducing a purge gas between the seal members, even if the airtightness is reduced, danger due to gas leakage is prevented. It has remarkable effects such as improved safety.

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明の一実施の形態を示す断面図。FIG. 1 is a cross-sectional view illustrating one embodiment of the present invention.

【図2】フランジが変形したときの状態を示す説明図。FIG. 2 is an explanatory diagram showing a state when a flange is deformed.

【図3】上フランジが変形したときの変形修正部材の取
り替えを示す説明図。
FIG. 3 is an explanatory view showing replacement of a deformation correcting member when an upper flange is deformed.

【図4】(a ),(b )はそれぞれ従来技術を説明する
断面図。
FIGS. 4A and 4B are cross-sectional views illustrating a conventional technique.

【符号の説明】[Explanation of symbols]

1...下フランジ、 2...上フランジ、 3...膨張型シール、 4...押さえ部材、 5...シール面部材、 6...締結ボルト用孔、 7...シール膨張用ガス導入経路、 8...パージガス導入経路、 9...パッキング、 10...遮蔽板、 11...ボルト、 12...フランジ冷却用の水冷水通路、 1. . . 1. lower flange, . . 2. Upper flange, . . 3. inflatable seal; . . Holding member, 5. . . 5. sealing face member; . . 6. holes for fastening bolts, . . 7. gas introduction path for seal inflation; . . 8. purge gas introduction path; . . Packing, 10. . . 10. a shielding plate; . . Bolts, 12. . . Water cooling water passage for flange cooling,

───────────────────────────────────────────────────── フロントページの続き (72)発明者 関口 毅 東京都千代田区丸の内一丁目1番2号 日 本鋼管株式会社内 (72)発明者 田口 憲彦 東京都千代田区丸の内一丁目1番2号 日 本鋼管株式会社内 (72)発明者 岩崎 克博 東京都千代田区丸の内一丁目1番2号 日 本鋼管株式会社内 (72)発明者 磯崎 進市 東京都千代田区丸の内一丁目1番2号 日 本鋼管株式会社内 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takeshi Sekiguchi 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Japan Inside of Kokan Kogyo Co., Ltd. (72) Inventor Norihiko Taguchi 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Sun Inside the Kokan Co., Ltd. (72) Inventor Katsuhiro Iwasaki 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Japan Inside the Kokan Co., Ltd. (72) Inventor Susumu Isozaki 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Japan Inside Steel Pipe Co., Ltd.

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】一対のフランジの少なくとも一方のシール
面に取替え可能かつ気密にシール面部材を取付け、この
シール面部材とこれに対向するフランジのシール面又は
シール面部材との間に両者間を気密に保持する2以上の
シール部材をフランジの径方向に列設してなることを特
徴とする、フランジのシール装置。
A replaceable and airtight seal surface member is mounted on at least one of the seal surfaces of a pair of flanges, and a gap between the seal surface member and the seal surface of the flange facing the seal member or the seal surface member is provided. A flange sealing device, wherein two or more sealing members for maintaining airtightness are arranged in a row in a radial direction of the flange.
【請求項2】シール部材はチューブシールで、このチュ
ーブシールにそれぞれシール膨張用ガスを導入するガス
経路が接続されている、請求項1に記載のフランジのシ
ール装置。
2. The flange sealing device according to claim 1, wherein the seal member is a tube seal, and a gas path for introducing a seal expansion gas is connected to each of the tube seals.
【請求項3】シール部材をシール面の所定位置に固定す
る押え部材と、二つのシール部材と一対のフランジとの
間に形成された空間内にパージガスを導入するガス経路
とを設けている、請求項1又は2に記載のフランジのシ
ール装置。
A pressure member for fixing the seal member at a predetermined position on the seal surface; and a gas path for introducing a purge gas into a space formed between the two seal members and the pair of flanges. The flange sealing device according to claim 1.
JP33879897A 1997-10-20 1997-12-09 Sealing device for flange Pending JPH11173428A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
JP33879897A JPH11173428A (en) 1997-12-09 1997-12-09 Sealing device for flange
CN98810337A CN1276862A (en) 1997-10-20 1998-10-19 Structure of metallurgical furnace and operating method using same metallurgical furnace
KR1020007003164A KR100339261B1 (en) 1997-10-20 1998-10-19 Structure of metallurgical furnace, exchanging method using the same metallurgical furnace, operating method using the same metallurgical furnace and seal device of flange used at the metallurgical furnace
PCT/JP1998/004703 WO1999020966A1 (en) 1997-10-20 1998-10-19 Structure of metallurgical furnace and operating method using the same metallurgical furnace
AU94629/98A AU751764B2 (en) 1997-10-20 1998-10-19 Structure of metallurgical furnace and operating method using the same metallurgical furnace
CA002307090A CA2307090C (en) 1997-10-20 1998-10-19 Structure of metallurgical furnace and operating method using the same metallurgical furnace
TW87117290A TW434318B (en) 1997-10-20 1998-10-20 Structure of metallurgical furnace and operating method using the same metallurgical furnace

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP33879897A JPH11173428A (en) 1997-12-09 1997-12-09 Sealing device for flange

Publications (1)

Publication Number Publication Date
JPH11173428A true JPH11173428A (en) 1999-06-29

Family

ID=18321579

Family Applications (1)

Application Number Title Priority Date Filing Date
JP33879897A Pending JPH11173428A (en) 1997-10-20 1997-12-09 Sealing device for flange

Country Status (1)

Country Link
JP (1) JPH11173428A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002048244A (en) * 2000-08-02 2002-02-15 Ulvac Japan Ltd Sealing method, sealing mechanism and vacuum treatment equipment
JP2003279045A (en) * 2002-03-20 2003-10-02 Koyo Thermo System Kk Hot air circulation type oven

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002048244A (en) * 2000-08-02 2002-02-15 Ulvac Japan Ltd Sealing method, sealing mechanism and vacuum treatment equipment
JP2003279045A (en) * 2002-03-20 2003-10-02 Koyo Thermo System Kk Hot air circulation type oven

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