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JP2678638B2 - Manufacturing method of butterfly valve - Google Patents
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JP2678638B2 - Manufacturing method of butterfly valve - Google Patents

Manufacturing method of butterfly valve

Info

Publication number
JP2678638B2
JP2678638B2 JP63272686A JP27268688A JP2678638B2 JP 2678638 B2 JP2678638 B2 JP 2678638B2 JP 63272686 A JP63272686 A JP 63272686A JP 27268688 A JP27268688 A JP 27268688A JP 2678638 B2 JP2678638 B2 JP 2678638B2
Authority
JP
Japan
Prior art keywords
valve
valve body
peripheral surface
inner peripheral
mold
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.)
Expired - Lifetime
Application number
JP63272686A
Other languages
Japanese (ja)
Other versions
JPH02120580A (en
Inventor
義則 万木
Original Assignee
株式会社巴技術研究所
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 株式会社巴技術研究所 filed Critical 株式会社巴技術研究所
Priority to JP63272686A priority Critical patent/JP2678638B2/en
Publication of JPH02120580A publication Critical patent/JPH02120580A/en
Application granted granted Critical
Publication of JP2678638B2 publication Critical patent/JP2678638B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Description

【発明の詳細な説明】 (産業上の利用分野) この発明は、鋼管の如き中空円筒状金属管体により形
成される弁本体を備えたバタフライ弁の製造方法に関す
る。
Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a butterfly valve including a valve body formed of a hollow cylindrical metal pipe body such as a steel pipe.

(従来の技術) 従来、バタフライ弁の弁本体は、最も一般的には鋳造
によって形成されており、配管パイプとの接続形態によ
ってフランジ型、ラグ型、ウェハー型等の構造がある
が、いずれにしても重量があり、取り扱いに不便である
と共に、配管パイプのフランジへの接続をためにボルト
・ナットを必要とし、且配管パイプとをバタフライ弁本
体との芯出しを正確にしなければならない為、配管の作
業性が悪いという問題があった。又、鋳造加工は、作業
性、作業環境等の面で問題点が多く好しい加工手段では
ない。
(Prior Art) Conventionally, the valve body of a butterfly valve is most commonly formed by casting, and there are flange-type, lug-type, wafer-type, etc. structures depending on the connection with the piping pipe. However, since it is heavy and inconvenient to handle, it requires bolts and nuts to connect the piping pipe to the flange, and the piping pipe and the butterfly valve body must be accurately centered. There was a problem that the workability of piping was poor. Further, casting is not a preferable processing means because it has many problems in terms of workability and working environment.

更に、鋳造品は重量がある関係上、弁本体内に配設さ
れるシートリングを金型を用いてライニング加工するこ
とが困難であり、一般には嵌め込み方式により装着され
ている。しかしながら、嵌め込み方式では、シートリン
グが脱落する危険性がある為、高流速、高差圧、高温な
どの流体条件では使用出来なかったり、或は発錆、腐食
の危険性があった。
Further, since the cast product has a heavy weight, it is difficult to perform a lining process on the seat ring arranged in the valve body by using a mold, and is generally mounted by a fitting method. However, in the fitting method, there is a risk that the seat ring will fall off, so that it cannot be used under fluid conditions such as high flow velocity, high differential pressure and high temperature, or there is a risk of rusting and corrosion.

特に近年流体輸送の効率化のために多用されて来てい
る小口径弁にあっては、シートリングを嵌め込みにより
装着した場合、シートリング脱落の危険が高く、実際上
採用出来ないという問題があった。
In particular, for small-diameter valves that have been widely used in recent years to improve the efficiency of fluid transportation, there is a problem that when the seat ring is fitted by fitting, there is a high risk of the seat ring falling off and it cannot be practically used. It was

(発明が解決しようとする課題) この発明は、従来の鋳造加工により提供されるバタフ
ライ弁にみられた問題点を解決せんとするものであり、
弁本体を鋼管の如き中空円筒状金属管体で形成せんとす
るものである。
(Problem to be Solved by the Invention) This invention is intended to solve the problems found in the butterfly valve provided by the conventional casting process.
The valve body is a hollow cylindrical metal tube body such as a steel tube.

(課題を解決するための手段) 上記課題を解決するために、この発明が採った手段
は、中空円筒状金属管体の直径方向対向位置に形成され
た軸孔に、フランジ部を管体の内周面に当接係止しつつ
弁棒ガイドを挿通して固着して弁本体を形成し、該弁本
体の外径寸法に合致するフランジ部を有する2分割の金
型を弁本体の両端開口から挿入してセットし、金型と弁
本体の前記弁棒ガイドのフランジ部を含む内周面の一部
との間に形成される空間に未加硫のライニング材料を充
填し、加熱加硫して前記弁棒ガイドのフランジ部を被覆
しつつ弁座を含むライニング層を弁本体の内周面の一部
に形成した後、該ライニング層に外周面を着座させつつ
円板状の弁体を弁本体内に配置し、弁棒を弁本体外方か
ら弁棒ガイドに挿入して弁体に連結するようにしたこと
を特徴とする。
(Means for Solving the Problem) In order to solve the above-mentioned problems, the means adopted by the present invention is such that a flange portion is provided in a shaft hole formed at a diametrically opposed position of a hollow cylindrical metal pipe body, and a flange portion of the pipe body is formed in the shaft hole. The valve rod guide is inserted through and fixed to the inner peripheral surface while being fixed to form a valve body, and a two-piece mold having a flange portion matching the outer diameter dimension of the valve body is provided at both ends of the valve body. Inserted from the opening and set, fill the unvulcanized lining material in the space formed between the mold and a part of the inner peripheral surface of the valve body including the flange portion of the valve rod guide, and heat After forming a lining layer including a valve seat on a part of the inner peripheral surface of the valve body while sulfurating to cover the flange portion of the valve rod guide, the disc-shaped valve while seating the outer peripheral surface on the lining layer Place the body inside the valve body and insert the valve stem into the valve stem guide from the outside of the valve body to connect it to the valve body. It is characterized by having done.

(実施例) 以下に図面を参照しつつ、この発明の好しい実施例を
詳細に説明する。図において(1)は、弁本体であっ
て、鋼管を所定長さに切断したものからなる。種々の配
管、例えば水道用、水輸送用、加熱炉用等に用いられる
鋼管は、使用温度や材質の相違にかかわらず一定の外径
寸法に規格が統一されている。したがって、かかる配管
用鋼管を弁本体として用いることにより、配管とバタフ
ライ弁との接続において外径寸法が一致する結果、芯出
しがきわめて簡単になると共に、従来の如きボルト締め
手段による必要がなく、バンド方式やジョイント方式で
接続することが可能となる。
(Embodiment) A preferred embodiment of the present invention will be described in detail below with reference to the drawings. In the figure, (1) is a valve body, which is formed by cutting a steel pipe into a predetermined length. Steel pipes used for various pipes, for example, for water supply, water transportation, heating furnaces, etc., have a uniform outer diameter standard regardless of the difference in operating temperature and material. Therefore, by using such a steel pipe for piping as the valve body, as a result of matching the outer diameter dimensions in the connection between the piping and the butterfly valve, centering becomes extremely simple and there is no need for conventional bolting means. It becomes possible to connect by a band method or a joint method.

弁本体(1)の内周面の一部はゴム等のエラストマー
材料からなるライニング層(2)で被覆される。該ライ
ニング層(2)の内周面中央部には、円周方向に延びる
弁座(3)が形成され、円板状の弁体(4)の外周縁が
接離して、弁の開閉をもたらす。
A part of the inner peripheral surface of the valve body (1) is covered with a lining layer (2) made of an elastomer material such as rubber. A valve seat (3) extending in the circumferential direction is formed in the center of the inner peripheral surface of the lining layer (2), and the outer peripheral edge of the disc-shaped valve body (4) is brought into contact with and separated from the valve seat (3) to open and close the valve. Bring

弁体(4)は、従来周知の手段例えば鋳造、鋳造等の
加工手段で形成された円板状の構造を有しており、同一
直径方向に対向して延び出す弁棒(5)(6)により弁
本体(1)に回動自在に軸支される。一方の弁棒(5)
は、弁本体(1)外に延び出して、所望の駆動手段(図
示せず)に連結され、弁体(4)に回転力を伝達する。
弁体(4)と、2本の弁棒(5)(6)とは、四角形、
六角形等の角接合やキー接合、或はテーパーボルト・ナ
ット等の適宜の結合手段により結合される。(7)、
(8)は、弁棒(5)(6)を軸挿する耐蝕製の弁棒ガ
イドであって、弁本体(1)の直径方向対向位置に形成
された軸孔(9)に弁本体(1)の内方から挿嵌され、
フランジ部(7a)(8a)を弁本体(1)の内周面に当接
係止して保持されつつ、溶接等の手段で固着される。弁
棒ガイド(7)(8)には、管状のグランド部材(10)
(11)が外挿され、管状グランド部材(10)(11)の一
端はそれぞれ弁本体(1)の外周面に溶接等の手段で固
着される。駆動側の弁棒(5)を軸挿する管状グランド
部材(10)は、外端を開放され、弁棒(5)が駆動手段
との連結のために、外方へ延び出すのを許容している。
他方の管状グランド部材(11)は、その外端をシール材
(13)を介して蓋板(12)で密閉されており、他方の弁
棒(6)は、この管状グランド部材(11)内において終
端している。
The valve body (4) has a disc-shaped structure formed by a conventionally known means, for example, a processing means such as casting, casting, etc., and the valve rods (5) (6) extending in opposition to each other in the same diameter direction. ) Is rotatably supported by the valve body (1). One stem (5)
Extends out of the valve body (1) and is connected to a desired drive means (not shown) to transmit the rotational force to the valve body (4).
The valve body (4) and the two valve rods (5) and (6) are squares,
The connection is made by a corner connection such as a hexagon, a key connection, or an appropriate connection means such as a taper bolt / nut. (7),
Reference numeral (8) is a corrosion-resistant valve rod guide into which the valve rods (5) and (6) are axially inserted. Inserted from the inside of 1),
The flange portions (7a) and (8a) are held in contact with and retained by the inner peripheral surface of the valve body (1), while being fixed by means such as welding. The valve rod guides (7) and (8) have tubular gland members (10).
(11) is externally inserted, and one ends of the tubular gland members (10) and (11) are fixed to the outer peripheral surface of the valve body (1) by means such as welding. The tubular gland member (10) for axially inserting the valve rod (5) on the driving side is opened at the outer end to allow the valve rod (5) to extend outward for connection with the driving means. ing.
The other tubular gland member (11) is sealed at its outer end with a lid plate (12) via a sealing material (13), and the other valve rod (6) is inside this tubular gland member (11). Ends in.

駆動側の管状グランド部材(10)の外端部には、弁棒
(5)の安定と回転の円滑性を保証するために弁棒ガイ
ド(14)が嵌挿される。
A valve rod guide (14) is fitted to the outer end of the driving-side tubular gland member (10) to ensure the stability and smoothness of rotation of the valve rod (5).

弁棒(5)と弁棒ガイド(14)との間をシールするた
めに、Oリング(15)等のシール手段(15)が適用され
る。
A sealing means (15) such as an O-ring (15) is applied to seal between the valve rod (5) and the valve rod guide (14).

第2図を参照して、弁本体(1)の内周面の一部に弁
座(3)を有するライニング層(2)を形成する方法を
説明する。ライニング層(2)は、金型を用いて未加硫
ゴム等のエラストマー材料を圧入し、加硫して、弁本体
(1)の内周面に焼付ることにより形成される。
A method for forming the lining layer (2) having the valve seat (3) on a part of the inner peripheral surface of the valve body (1) will be described with reference to FIG. The lining layer (2) is formed by press-fitting an elastomer material such as unvulcanized rubber using a mold, vulcanizing it, and baking it on the inner peripheral surface of the valve body (1).

成形用金型は、第1及び第2の2個の金型(16、17)
からなり、第1の金型(16)は、上部外周面に弁座成形
部(18)を有した円筒体(19)と、該円筒体(19)の下
部に断面状の溝部(20)を介して連続するフランジ部
(21)とを備えた形状を有し、弁座成型部(18)と円筒
体(19)とは所定形状及び肉厚の弁座(3)と弁本体内
周面のライニング層(2)を形成する。弁座成形部(1
8)には、直径方向に延びる治具挿通孔(22)が貫通し
て形成される。又、フランジ部(21)の内径は、弁本体
(1)の外径と略一致しており、第1金型(16)をセッ
トしたとき、金型のガタ付きが発生するおそれはない。
図に示すように、治具(23)を弁棒ガイド(7)(8)
を介して、治具挿通孔(22)に挿入するとき、弁本体
(1)の端部(1′)と溝部(20)の底面との間に所定
の間隔が形成される。第2の金型(17)は、前記第1の
金型(16)の上に積み重ねられる円筒体(24)と、該円
筒体(24)の上部に断面状の溝部(25)を介して連続
するフランジ部(26)を備える。円筒体(24)、溝部
(25)並びにフランジ部(26)は、前記第1の金型の円
筒体(19)、溝部(20)、フランジ部(21)と同様の機
能を有し、弁本体(1)の軸方向長さと外径とを規制す
る。
The molding dies are the first and second two dies (16, 17)
The first mold (16) is composed of a cylindrical body (19) having a valve seat molding portion (18) on an outer peripheral surface of an upper portion thereof, and a groove portion (20) having a cross section at a lower portion of the cylindrical body (19). The valve seat molding part (18) and the cylindrical body (19) have a predetermined shape and thickness, and a valve seat (3) and a valve body inner circumference. The surface lining layer (2) is formed. Valve seat forming part (1
A jig insertion hole (22) extending in the diametrical direction is formed through 8). Further, the inner diameter of the flange portion (21) is substantially the same as the outer diameter of the valve body (1), and there is no risk of rattling of the mold when the first mold (16) is set.
As shown in the figure, attach the jig (23) to the valve stem guide (7) (8).
When inserted into the jig insertion hole (22) via the, a predetermined space is formed between the end (1 ′) of the valve body (1) and the bottom surface of the groove (20). The second mold (17) includes a cylindrical body (24) stacked on the first mold (16), and a groove (25) having a cross section in the upper part of the cylindrical body (24). A continuous flange portion (26) is provided. The cylinder (24), the groove (25) and the flange (26) have the same functions as the cylinder (19), the groove (20) and the flange (21) of the first mold, The axial length and outer diameter of the body (1) are regulated.

第2の金型(17)の下部外周面には、前記第1の金型
(16)の弁座成型部(18)に連続するライニング層成型
部(27)が形成され、第1、第2の金型(16)(17)
は、弁座部を外れた位置においてパーティングライン
(28)を成すように接合される。
A lining layer molding part (27) continuous with the valve seat molding part (18) of the first mold (16) is formed on the outer peripheral surface of the lower part of the second mold (17). Two molds (16) (17)
Are joined so as to form a parting line (28) at a position outside the valve seat portion.

治具(23)を弁棒ガイド(7)(8)から治具挿通孔
(19)に挿通しつつ第2図に示すように第1、第2の金
型(16)(17)を順次積み重ねて、弁本体(1)にセッ
トするとき、第1、第2の金型(16)(17)と弁本体
(1)とは、フランジ部(21)(26)と弁本体(1)の
外周面との挿嵌関係により、正確に位置を設定されて組
み合わされ、第1、第2の金型(16)(17)と弁本体
(1)の内周面との間にライニング層を成型するための
所要の間隔が形成される。
While inserting the jig (23) from the valve rod guides (7) and (8) into the jig insertion hole (19), the first and second molds (16) and (17) are sequentially inserted as shown in FIG. When stacked and set on the valve body (1), the first and second molds (16) (17) and the valve body (1) are the flange portions (21) (26) and the valve body (1). The lining layer is positioned between the first and second molds (16) and (17) and the inner peripheral surface of the valve body (1) by accurately setting the position of the lining layer and the outer peripheral surface of the valve body. The required spacing for molding is formed.

実際のライニング層(2)の成形に際しては、先ず第
1金型(16)を弁本体(1)にセットした後、ライニン
グ層成型用空間内に未加硫のエラストマー材料を圧入
し、しかる後、第2の金型(17)をセットし、加熱して
加硫を行うようにする。加硫完了後、第2の金型(17)
を上方へ取り出し、治具(23)を抜いて、第1の金型
(16)からライニング層(2)が形成された弁本体
(1)を上方へ抜き出す。その後、圧入時の余分のエラ
ストマーが弁本体(1)と金型(16)(17)の隙間には
み出しているので、これを切除して完成品を得る。
In the actual molding of the lining layer (2), first, the first mold (16) is set on the valve body (1), and then the unvulcanized elastomer material is press-fitted into the lining layer molding space, and then Then, the second mold (17) is set and heated so as to perform vulcanization. After the vulcanization is completed, the second mold (17)
Is taken out upward, the jig (23) is pulled out, and the valve body (1) having the lining layer (2) formed thereon is pulled out upward from the first mold (16). After that, the extra elastomer at the time of press-fitting protrudes into the gap between the valve body (1) and the molds (16) and (17), and is cut off to obtain a finished product.

(発明の作用及び効果) この発明によれば、弁本体の内周面及び端面を金型を
用いた加硫手段により弁座を含むライニング層を焼付け
て装着することが出来るため、ライニング層の密着性が
良く広範囲の流体条件に対応することが可能となり、広
範囲な用途に適合可能なバタフライ弁を提供することが
出来る。
(Operation and Effect of the Invention) According to the present invention, since the lining layer including the valve seat can be baked and attached to the inner peripheral surface and the end surface of the valve body by the vulcanizing means using the mold, It is possible to provide a butterfly valve that has good adhesion and can handle a wide range of fluid conditions, and that can be adapted to a wide range of applications.

ライニング層は、弁本体の外径寸法を基準としてセッ
トされる金型により成型される為、弁座内径寸法が安定
し全閉時におけるシール性の向上をもたらすシートリン
グとなるライニング層の施工が出来、高品質、高性能の
製品を得ることが出来る。
Since the lining layer is molded by a mold that is set based on the outer diameter of the valve body, the lining layer that becomes the seat ring that stabilizes the inner diameter of the valve seat and improves the sealing performance when fully closed can be installed. It is possible to obtain high quality, high performance products.

又、弁座を含むライニング層は、弁本体の内周面を部
分的に被覆する構造である為、高価なエラストマー材料
の使用を必要とする場合に、特に経済性の向上を図るこ
とが出来る。
Further, since the lining layer including the valve seat has a structure that partially covers the inner peripheral surface of the valve body, it is possible to particularly improve the economical efficiency when it is necessary to use an expensive elastomer material. .

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

第1図は縦断面図、第2図は金型と弁本体とのセット状
態を示す縦断面図である。 (1)……弁本体、(2)……ライニング層 (3)……弁座、(4)……弁体 (5)……弁棒、(6)……弁棒 (7)……弁棒ガイド、(8)……弁棒ガイド (9)……軸孔、(10)……管状グランド部材 (11)……管状グランド部材、(12)……蓋体 (13)……シール材、(14)……弁棒ガイド (15)……シール手段、(16)……第1金型 (17)……第2金型、(18)……弁座成型部 (19)……円筒体、(20)……溝部 (21)……フランジ部、(22)……治具挿通孔 (23)……治具、(24)……円筒体 (25)……溝部、(26)……フランジ部 (27)……ライニング層成型部、(28)……パーティン
グライン
FIG. 1 is a vertical sectional view, and FIG. 2 is a vertical sectional view showing a set state of a mold and a valve body. (1) …… Valve body, (2) …… lining layer (3) …… Valve seat, (4) …… Valve body (5) …… Valve rod, (6) …… Valve rod (7) …… Valve rod guide, (8) …… valve rod guide (9) …… shaft hole, (10) …… tubular gland member (11) …… tubular gland member, (12) …… cover (13) …… seal Material, (14) …… Valve guide (15) …… Seal means, (16) …… First mold (17) …… Second mold, (18) …… Valve seat molding part (19)… … Cylinder, (20) …… Groove (21) …… Flange, (22) …… Jig insertion hole (23) …… Jig, (24) …… Cylinder (25) …… Groove, ( 26) …… Flange part (27) …… Lining layer molding part, (28) …… Parting line

Claims (1)

(57)【特許請求の範囲】(57) [Claims] 【請求項1】中空円筒状金属管体の直径方向対向位置に
形成された軸孔に、フランジ部を管体の内周面に当接係
止しつつ弁棒ガイドを挿通して固着して弁本体を形成
し、該弁本体の外径寸法に合致するフランジ部を有する
2分割の金型を弁本体の両端開口から挿入してセット
し、金型と弁本体の前記弁棒ガイドのフランジ部を含む
内周面の一部との間に形成される空間に未加硫のライニ
ング材料を充填し、加熱加硫して前記弁棒ガイドのフラ
ンジ部を被覆しつつ弁座を含むライニング層を弁本体の
内周面の一部に形成した後、該ライニング層に外周面を
着座させつつ円板状の弁体を弁本体内に配置し、弁棒を
弁本体外方から弁棒ガイドに挿入して弁体に連結するよ
うにしたことを特徴とするバタフライ弁の製造方法。
1. A valve rod guide is inserted into and fixed to a shaft hole formed in a diametrically opposed position of a hollow cylindrical metal tube body while abutting and locking the flange portion against the inner peripheral surface of the tube body. A valve body is formed, and a two-divided mold having a flange portion matching the outer diameter of the valve body is inserted and set from both openings of the valve body, and the flange of the valve rod guide of the mold and the valve body is set. The space formed between the inner peripheral surface including a part and a part of the inner peripheral surface is filled with an unvulcanized lining material, and the material is heated and vulcanized to cover the flange portion of the valve rod guide and a lining layer including a valve seat. After forming a part of the inner peripheral surface of the valve body, the disc-shaped valve body is placed inside the valve body while the outer peripheral surface is seated on the lining layer, and the valve stem is guided from the outside of the valve body to the valve stem guide. A method for manufacturing a butterfly valve, characterized in that the butterfly valve is inserted into a valve and connected to a valve body.
JP63272686A 1988-10-28 1988-10-28 Manufacturing method of butterfly valve Expired - Lifetime JP2678638B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP63272686A JP2678638B2 (en) 1988-10-28 1988-10-28 Manufacturing method of butterfly valve

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP63272686A JP2678638B2 (en) 1988-10-28 1988-10-28 Manufacturing method of butterfly valve

Related Child Applications (1)

Application Number Title Priority Date Filing Date
JP34842795A Division JPH08240272A (en) 1995-12-18 1995-12-18 Butterfly valve

Publications (2)

Publication Number Publication Date
JPH02120580A JPH02120580A (en) 1990-05-08
JP2678638B2 true JP2678638B2 (en) 1997-11-17

Family

ID=17517383

Family Applications (1)

Application Number Title Priority Date Filing Date
JP63272686A Expired - Lifetime JP2678638B2 (en) 1988-10-28 1988-10-28 Manufacturing method of butterfly valve

Country Status (1)

Country Link
JP (1) JP2678638B2 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2528709Y2 (en) * 1990-06-28 1997-03-12 株式会社巴技術研究所 Butterfly valve

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5134026Y2 (en) * 1973-02-21 1976-08-23
JPS6064824U (en) * 1983-10-12 1985-05-08 科研工業株式会社 butterfly valve
JPH0814324B2 (en) * 1986-04-18 1996-02-14 高砂熱学工業株式会社 Butterfly valve

Also Published As

Publication number Publication date
JPH02120580A (en) 1990-05-08

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