JPS63180338A - Forging and forming method for nozzle part - Google Patents
Forging and forming method for nozzle partInfo
- Publication number
- JPS63180338A JPS63180338A JP62012029A JP1202987A JPS63180338A JP S63180338 A JPS63180338 A JP S63180338A JP 62012029 A JP62012029 A JP 62012029A JP 1202987 A JP1202987 A JP 1202987A JP S63180338 A JPS63180338 A JP S63180338A
- Authority
- JP
- Japan
- Prior art keywords
- body member
- nozzle
- main body
- punch
- nozzle part
- 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
Links
- 238000000034 method Methods 0.000 title claims abstract description 21
- 238000005242 forging Methods 0.000 title claims description 7
- 239000000463 material Substances 0.000 claims description 18
- 238000005096 rolling process Methods 0.000 abstract description 2
- 238000000465 moulding Methods 0.000 description 5
- 230000007547 defect Effects 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 238000005452 bending Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000003754 machining Methods 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E30/00—Energy generation of nuclear origin
- Y02E30/30—Nuclear fission reactors
Landscapes
- Forging (AREA)
Abstract
Description
【発明の詳細な説明】
〈発明の目的〉
産業上の利用分野
本発明はノズル部の精造成形方法に係り、詳しくは、原
子炉その他の圧力容器本体の一部として供される本体部
材にノズル部を一体に鍛造成形するノズル部の鍛造成形
方法に係る。[Detailed Description of the Invention] <Object of the Invention> Industrial Field of Application The present invention relates to a method for precision molding of a nozzle part, and more particularly, to a method for forming a main body member used as a part of the main body of a pressure vessel such as a nuclear reactor. The present invention relates to a forging method for a nozzle part, in which the nozzle part is integrally forged.
従 来 の 技 術
一般に、原子炉等の圧力容器本体には多くのノズルが取
付けられる。口のノズル類は通常本体部材とは別個に製
造され溶接によって一体に接合されている。しかしなが
ら、圧力容器本体は安全性の観点から溶接線がより少な
いことが望まれ、この点から、圧力容器の本体部材とノ
ズル部とを一体で製造する方法が提案されている。その
一つとして、特公昭５７−２４１８号公報は板材を素材
として、この板材に下孔をあけてポンチで押下げ、所謂
バーリング加工を行なってノズル部を成形する方法が提
案されているが、この場合に成形できるノズル部の肉厚
や高さは素材の板厚、下孔の直径、ポンチの外径等に支
配されて所望の高さと肉厚を有するノズルを形成するこ
とができず、また、最も高応力となるノズル内面のコー
ナ一部の丸みが非常に大きくなり、所望形状を得ること
ができない欠点があった。Conventional technology In general, many nozzles are attached to the main body of a pressure vessel such as a nuclear reactor. The mouth nozzles are usually manufactured separately from the main body member and joined together by welding. However, from the viewpoint of safety, it is desired that the pressure vessel main body has fewer weld lines, and from this point of view, a method has been proposed in which the main body member and the nozzle portion of the pressure vessel are manufactured integrally. As one such method, Japanese Patent Publication No. 57-2418 proposes a method of forming a nozzle part by using a plate material as a material, drilling a pilot hole in the plate material and pressing it down with a punch, and performing a so-called burring process. In this case, the thickness and height of the nozzle part that can be formed are controlled by the thickness of the material, the diameter of the pilot hole, the outer diameter of the punch, etc., and it is not possible to form a nozzle with the desired height and thickness. In addition, a part of the corner of the inner surface of the nozzle, where the stress is the highest, becomes extremely rounded, making it impossible to obtain a desired shape.
また、特開昭５８−２２１６２１号公報にはバーリング
加工の前に素材の内側からノズル内径にほぼ等しい直径
を有し、先端面を平坦としてポンチを素材の肉厚の０．
２〜０．３倍の深さまで押込んで凹み加工を行なうこと
により、ダイス肩を支点として曲げ変形を抑制し、ノズ
ル内面コーナ一部のダレを小さくすることが提案されて
いる。Furthermore, Japanese Patent Application Laid-open No. 58-221621 discloses that before burring, a punch with a diameter approximately equal to the inner diameter of the nozzle is used from the inside of the material, the tip surface is flattened, and the punch is 0.00 mm in thickness of the material.
It has been proposed to suppress bending deformation using the die shoulder as a fulcrum by pressing the die to a depth of 2 to 0.3 times to form a dent, thereby reducing sag at a part of the inner corner of the nozzle.
しかし、これらの何れの場合においても素材の肉厚が厚
くなると、バーリング加工した時に、下孔部分で剪断変
形が支配的となり、第３図に示すようにノズル先端部の
肉厚比（ノズル先端厚ｌ′素材肉厚）が急激に減少し、
ノズル形状に成形できないという共通の問題があった。However, in any of these cases, when the wall thickness of the material becomes thick, shear deformation becomes dominant in the pilot hole part when burring is performed, and as shown in Figure 3, the wall thickness ratio of the nozzle tip (nozzle tip The thickness l′ (material thickness) decreases rapidly,
A common problem was that it could not be molded into a nozzle shape.
発明が解決しようとする問題点
本発明は上記欠点の解決を目的とし、具体的には、圧力
容器等の本体部材の一部とノズル部とを一体に成形する
際に、曲げ支配の塑性変形を行なわせることにより、所
望の高さならびに肉厚を有するノズル部を経済的に鍛造
により成形できるノズル部の鍛造成形方法を提案する。Problems to be Solved by the Invention The present invention aims to solve the above-mentioned drawbacks. Specifically, when a part of a main body member such as a pressure vessel and a nozzle part are integrally molded, plastic deformation dominated by bending is avoided. We propose a forging method for a nozzle part that can economically form a nozzle part having a desired height and wall thickness by performing the following steps.
〈発明の構成〉
問題点を解決するための
手段ならびにその作用
本発明は、圧力容器本体の一部として供される本体部材
とノズル部とを一体に熱間成形する際に、前記ノズル部
に対応するところに、予め下記条件に適合するよう凹部
と、該凹部の中央部に下孔を設け、口の下孔を介して、
該下孔と同心円状にセットされたポンチとダイとによっ
て熱間成形し、本体部材にノズル部を一体に成形するこ
とを特徴とする。<Structure of the Invention> Means for Solving the Problems and Their Effects The present invention provides that when a main body member provided as a part of a pressure vessel main body and a nozzle part are integrally hot-formed, the nozzle part is At the corresponding locations, a recess is provided in advance to meet the following conditions, and a pilot hole is provided in the center of the recess, and the opening is inserted through the pilot hole.
It is characterized in that the nozzle portion is integrally formed into the main body member by hot forming using a punch and die set concentrically with the pilot hole.
Ｄ／Ｔ≧１，２ Ｔ＞０．６Ｔ。D/T≧1,2 T>0.6T.
但し、 Ｄ・・・・・・ポンチ径
■・・・・・・凹部における素材の厚み■０・・・・・
・素材の元厚
以下、図面によって本発明の手段たる構成ならびに作用
について説明すると、次の通りである。However, D... Punch diameter ■ Thickness of material at concave part ■ 0...
・Below the original thickness of the material, the structure and operation of the means of the present invention will be explained with reference to the drawings as follows.
第１図は本発明方法を実施する一例の説明図であり、第
２図（ａ）は本発明方法で成形されたノズル部の一例の
縦断面図、第２図（ｂ）は比較例で成形されたノズル部
の一例の縦断面図であり、第３図はノズル先端部と素材
厚の肉厚比とポンチ径（Ｄ）／素材肉厚ｍの関係を示し
たグラフであり、第４図は表面欠陥発生率と凹部の深さ
くＴ。FIG. 1 is an explanatory diagram of an example of implementing the method of the present invention, FIG. 2(a) is a longitudinal cross-sectional view of an example of a nozzle part formed by the method of the present invention, and FIG. 2(b) is a comparative example. FIG. 3 is a longitudinal cross-sectional view of an example of a molded nozzle part, and FIG. The figure shows surface defect occurrence rate and recess depth T.
−Ｔ’ｌ／本体部材の肉厚（■０）の関係を示したグラ
フである。It is a graph showing the relationship between -T'l/thickness of the main body member (■0).
本発明者等は、圧力容器等の本体部材とノズル部とを経
済的に、かつ所望のノズル寸法で一体に成形する調造法
を開発するために多くの実験を重ねたところ、従来例の
ように平板状素材からバーリング加工によってノズル部
を成形する際に、ノズルの内径で決まるポンチの直径（
０）と素材の肉厚（■０）との比Ｄ／Ｔｏが１．２より
小さいときは第３図に示すように下孔部分で剪断変形が
支配的になり、ノズル先端部の肉厚比が小さくなり、ノ
ズル形状に成形することができないことが分った。本発
明成形方法はこれらの知見により完成したものである。The inventors of the present invention conducted many experiments to develop a preparation method for integrally molding the main body member of a pressure vessel etc. and the nozzle part economically and with desired nozzle dimensions, and found that When forming a nozzle part from a flat material by burring, the diameter of the punch determined by the inner diameter of the nozzle (
When the ratio D/To of 0) and the material thickness (■0) is smaller than 1.2, shear deformation becomes dominant in the pilot hole, as shown in Figure 3, and the wall thickness at the nozzle tip decreases. It was found that the ratio became small and it was impossible to mold it into a nozzle shape. The molding method of the present invention was completed based on these findings.
第１図は本発明方法によって本体部材と一体にノズル部
を鍛造成形する場合の一例の説明図である。本体部材３
にノズル部を成形する場合に、予め、本体部材３のノズ
ル取付部に対応するところに凹部４を形成する。この凹
部４は本体部材３を鋼塊から鍛造あるいは圧延またはそ
の組み合わせ等で製造した後に、機械加工あるいは他の
適正な方法でノズル取付部に形成できる。FIG. 1 is an explanatory diagram of an example of a case in which a nozzle portion is forged integrally with a main body member by the method of the present invention. Main body member 3
When molding the nozzle portion, a recess 4 is formed in advance at a location corresponding to the nozzle attachment portion of the main body member 3. The recess 4 can be formed in the nozzle mounting portion by machining or other suitable methods after the main body member 3 is manufactured from a steel ingot by forging, rolling, or a combination thereof.
次に、この本体部材３において凹部４の略々中央部に下
孔５を形成し、この下孔５にポンチ１を押下げて第２図
（ａ）に示す如く、ノズル部６ａを一体に成形する。こ
の場合、凹部４はノズル部成形に必要な分だけの材料が
確保できるものであれば良いが、一般には、凹部４は成
形しようとするノズル部の内径より若干小さな直径を有
するように構成する。また、凹部４の深さは成形すべき
ノズル部の形状によって変化させるが、通常、本体部材
３の肉厚の０，４倍以下とする。すなわち、第４図に示
すように凹部の深さが本体部材の肉厚の０．４倍以上に
なると、バーリング加工する場合に成形したノズル内面
の表面欠陥発生率が急激に上昇するので０．４倍以下と
するっ凹部厚みｍと素材の元厚（Ｔｏ）の比は、（Ｔｏ
−Ｔｌ／Ｔｏ ＜ ０．４
従って、 Ｔ／Ｔｏ ＞ ０．６
また、前記のように第３図よりポンチ直径（Ｄ）と凹部
の厚み（Ｔ）との比は、
Ｄ／Ｔ≧１．２
とすることによって肉厚比が改良され、良好なノズル形
状が得られる。Next, a pilot hole 5 is formed in the main body member 3 at approximately the center of the recess 4, and the punch 1 is pushed down into the pilot hole 5 to assemble the nozzle portion 6a into one piece, as shown in FIG. 2(a). Shape. In this case, the recess 4 may be of any size as long as it can secure enough material to mold the nozzle, but generally the recess 4 is configured to have a diameter slightly smaller than the inner diameter of the nozzle to be molded. . Further, the depth of the recess 4 varies depending on the shape of the nozzle portion to be molded, but is usually 0.4 times or less the thickness of the main body member 3. That is, as shown in FIG. 4, when the depth of the recess becomes 0.4 times or more the thickness of the main body member, the incidence of surface defects on the inner surface of the molded nozzle during burring increases rapidly. The ratio of the concave thickness m and the original thickness of the material (To), which should be 4 times or less, is (To
-Tl/To < 0.4 Therefore, T/To > 0.6 Also, as mentioned above, from FIG. 3, the ratio of the punch diameter (D) to the thickness of the recess (T) is D/T≧1. 2, the wall thickness ratio is improved and a good nozzle shape can be obtained.
以上の通りに一体に成形する場合に、通常はポンチ１と
ダイ２とを所定のプレス装置に組入れてから本体部材３
を所定の温度に加熱保持してダイ２にセットする。その
後、ポンチ１を通常の速度で圧下して本体部材３に目通
させると、本体部材には所望のノズルｉ６ａが第２図ｆ
ａ）に示すように成形できる。When integrally molding as described above, normally the punch 1 and the die 2 are assembled into a predetermined press device, and then the main body member 3 is assembled.
is heated and maintained at a predetermined temperature and set in die 2. Thereafter, when the punch 1 is pushed down at a normal speed and passed through the main body member 3, the desired nozzle i6a is formed in the main body member as shown in FIG.
It can be molded as shown in a).
実施例 次に、実施例によって説明すると、次の通りである。Example Next, an example will be explained as follows.
マス、ＳＡ ５０８ Ｇ１−３材の鋼塊から鍛造して肉
厚３００市に成形し、これを本体部材３の母板とした。The mass was forged from a steel ingot made of SA 508 G1-3 material and formed into a wall thickness of 300 mm, and this was used as the base plate of the main body member 3.
その後、この母板から機械加工で、直径２９０１１１＋
１１φ、高さく３０ｍの凹部４を形成した。この本体部
材３において凹部４の略々中央部に直径１００嗣φの下
孔５を形成したのち、本体部材３は１２００℃に加熱し
た。なお、下孔５を先に形成した後、凹ｇＢ４を形成し
てもよい。After that, by machining from this mother plate, the diameter 290111+
A recess 4 with a diameter of 11 and a height of 30 m was formed. After forming a pilot hole 5 with a diameter of 100 mm approximately in the center of the recess 4 in this main body member 3, the main body member 3 was heated to 1200°C. Note that the recess gB4 may be formed after the pilot hole 5 is formed first.
一方、直径２９０ｓφのポンチ１を用意し、このポンチ
１の先端形状は半頂角５０″の円錐状とし、更に、内径
５００ｓφのダイ２を用意し、このダイ２の内径のコー
ナ一部には半径７５ｍｍの丸味をつけた。On the other hand, a punch 1 with a diameter of 290 sφ is prepared, and the tip of this punch 1 has a conical shape with a half apex angle of 50''. Furthermore, a die 2 with an inner diameter of 500 sφ is prepared, and a part of the inner diameter corner of this die 2 is Rounded with a radius of 75mm.
、そこで、このポンチ１とダイ２とを６０００１−ンプ
レスに組み込み、上記のように加熱保持された本体部材
３をダイ２の上にセットし、ポンチ１を通常の速度で圧
下したところ、第２図（ａ）に示す如く、ノズル部６ａ
が成形できた。また、比較のために、通常の平板をその
まま使用し、同様の下孔をあけ、同一のポンチとダイを
用いて熱間鍛造を行なったところ、第２図（ｂｌに示す
如くノズル部６ｂを有する本体部材３が得られた。Therefore, this punch 1 and die 2 were assembled into a 60001-n press, the main body member 3 heated and held as described above was set on top of the die 2, and the punch 1 was pressed down at a normal speed. As shown in Figure (a), the nozzle part 6a
was able to be formed. For comparison, a normal flat plate was used as it was, a similar pilot hole was drilled, and hot forging was performed using the same punch and die. A main body member 3 having the following properties was obtained.
第２図＋ａ＞と（ｂ）を比較すると明らかなように、本
発明方法によって成形されたノズル部は高さならびに肉
厚分布が比較例に較べるときわめてすぐれていることが
わかった。As is clear from a comparison of FIGS. 2+a> and (b), the nozzle portion formed by the method of the present invention was found to be extremely superior in height and wall thickness distribution compared to the comparative example.
なお、ダイ２の内径部は開放型として実施したが、この
開放型の他に閉塞型としても良好なノズル部を得ること
ができる。Although the inner diameter portion of the die 2 is an open type, a good nozzle portion can be obtained by using a closed type instead of this open type.
〈発明の効果〉
以上詳しく説明したように、本発明は、圧力容器本体の
一部として供される本体部材とノズル部とを一体に熱間
成形する際に、前記ノズル部に対応するところに、予め
、０／Ｔ≧１．２、■〉０．６Ｔｏに適合するよう凹部
を成形した後、凹部の中央部に下孔を設け、この下孔を
介して、同心円状にセットされたポンチとダイとによっ
て熱間成形し、本体部材にノズル部を一体に成形するこ
とを特徴とするノズル部の鍛造成形方法であって、ポン
チ径（旧、四部の厚み（Ｔｌおよび素材の元厚（工０）
をコントロールすることによって従来法の欠陥を改良し
、所望の高さおよび肉厚を有するノズルを形成すること
ができるようになった。<Effects of the Invention> As explained in detail above, the present invention provides a method for forming a part corresponding to the nozzle part when hot-forming the main body member and the nozzle part, which are provided as a part of the pressure vessel main body, together. , After forming a recess in advance to meet 0/T≧1.2, ■>0.6To, a pilot hole is provided in the center of the recess, and a punch set concentrically is inserted through the pilot hole. This is a forging method for a nozzle part, which is characterized by hot forming the nozzle part with a main body member and a die, and forming the nozzle part integrally with the main body member. 0)
By controlling this, it has become possible to improve the defects of the conventional method and form a nozzle with a desired height and wall thickness.
第１図は本発明方法を実施する一例の説明図、第２図＋
ａｌは本発明方法で成形されたノズル部の一例の縦断面
図、第２図（ｂ）は比較例で成形されたノズル部の一例
の縦断面図、第３図はノズル先端部と素材厚の肉厚比と
ポンチ径ｌ′素材肉厚の関係を示したグラフ、第４図は
表面欠陥発生率と凹部の深さ／本体部材の肉厚の関係を
示したグラフである。
符号１・・・・・・ポンチ
２・・・・・・ダイ
３・・・・・・本体部材（被鍛造物）
４・・・・・・凹部
５・・・・・・下孔
６・・・・・・ノズル部Figure 1 is an explanatory diagram of an example of implementing the method of the present invention, Figure 2 +
al is a vertical sectional view of an example of a nozzle part molded by the method of the present invention, FIG. 2(b) is a vertical sectional view of an example of a nozzle part molded by a comparative example, and FIG. FIG. 4 is a graph showing the relationship between the thickness ratio of the punch diameter l' and the material thickness, and FIG. 4 is a graph showing the relationship between the surface defect occurrence rate and the depth of the recess/the thickness of the main body member. Code 1... Punch 2... Die 3... Main body member (forged object) 4... Concavity 5... Pilot hole 6.・・・・・・Nozzle part
Claims (1)
とを一体に熱間成形する際に、前記ノズル部に対応する
ところに、予め下記条件に適合するよう凹部と、該凹部
の中央部に下孔を設け、この下孔を介して、該下孔と同
心円状にセットされたポンチとダイとによって熱間成形
し、本体部材にノズル部を一体に成形することを特徴と
するノズル部の鍛造成形方法。 Ｄ／Ｔ≧１．２ Ｔ＞０．６Ｔ＿０ 但し、Ｄ……ポンチ径 Ｔ……凹部における素材の厚み Ｔ＿０……素材の元厚[Claims] When hot-forming the main body member and the nozzle part, which are provided as part of the pressure vessel main body, into one body, a recess is formed in advance in a place corresponding to the nozzle part so as to meet the following conditions. A pilot hole is provided in the center of the recess, and hot forming is performed through the pilot hole using a punch and die set concentrically with the pilot hole to integrally mold the nozzle portion into the main body member. A forging method for a nozzle part characterized by: D/T≧1.2 T>0.6T_0 However, D...Punch diameter T...Thickness of the material at the recess T_0...Original thickness of the material
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62012029A JPS63180338A (en) | 1987-01-20 | 1987-01-20 | Forging and forming method for nozzle part |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62012029A JPS63180338A (en) | 1987-01-20 | 1987-01-20 | Forging and forming method for nozzle part |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63180338A true JPS63180338A (en) | 1988-07-25 |
Family
ID=11794175
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62012029A Pending JPS63180338A (en) | 1987-01-20 | 1987-01-20 | Forging and forming method for nozzle part |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63180338A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010218583A (en) * | 2010-07-05 | 2010-09-30 | Nec Corp | I/o processing device and method |
-
1987
- 1987-01-20 JP JP62012029A patent/JPS63180338A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010218583A (en) * | 2010-07-05 | 2010-09-30 | Nec Corp | I/o processing device and method |
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