JPH0229168B2 - DENJIRYURYOKEINOSEIZOHOHO - Google Patents
DENJIRYURYOKEINOSEIZOHOHOInfo
- Publication number
- JPH0229168B2 JPH0229168B2 JP16911382A JP16911382A JPH0229168B2 JP H0229168 B2 JPH0229168 B2 JP H0229168B2 JP 16911382 A JP16911382 A JP 16911382A JP 16911382 A JP16911382 A JP 16911382A JP H0229168 B2 JPH0229168 B2 JP H0229168B2
- Authority
- JP
- Japan
- Prior art keywords
- outer casing
- measuring tube
- welding
- nickel
- joint
- 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
Links
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 26
- 229910001141 Ductile iron Inorganic materials 0.000 claims description 10
- 238000005304 joining Methods 0.000 claims description 8
- 229910052759 nickel Inorganic materials 0.000 claims description 8
- 238000000034 method Methods 0.000 claims description 6
- 229910000963 austenitic stainless steel Inorganic materials 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 238000003466 welding Methods 0.000 description 30
- 229910000990 Ni alloy Inorganic materials 0.000 description 6
- 239000007789 gas Substances 0.000 description 6
- 238000010586 diagram Methods 0.000 description 3
- 239000012530 fluid Substances 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 230000001681 protective effect Effects 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000010894 electron beam technology Methods 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- 230000035515 penetration Effects 0.000 description 2
- 239000004809 Teflon Substances 0.000 description 1
- 229920006362 Teflon® Polymers 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 150000002815 nickel Chemical class 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
- G01F1/56—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using electric or magnetic effects
- G01F1/58—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using electric or magnetic effects by electromagnetic flowmeters
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Volume Flow (AREA)
Description
【発明の詳細な説明】
〔発明の技術分野〕
この発明は電磁流量計の製造方法に係り、特に
測定管と外筐との接合方法の改良に関する。DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing an electromagnetic flowmeter, and particularly to an improvement in a method for joining a measuring tube and an outer casing.
第１図は従来の電磁流量計の構造を示した断面
図である。流体を通す非磁性体の測定管１はこれ
を収納する外筐５の内壁面で接合され、接合部７
を有する。
FIG. 1 is a sectional view showing the structure of a conventional electromagnetic flowmeter. A measuring tube 1 made of a non-magnetic material through which a fluid passes is joined at the inner wall surface of an outer casing 5 that houses it, and a joining part 7 is formed.
has.
また１対の電極２が測定管１に対し管軸に直交
配設されている。また１対の電極２を結ぶ線と測
定管１の管軸とにそれぞれ直交する直径軸線上に
配設され外筐の一部を兼ねる磁極３および３′が
設けられる。この磁極３，３′にはコイル４，
４′が巻回されている。 Further, a pair of electrodes 2 are arranged perpendicularly to the tube axis of the measuring tube 1. Further, magnetic poles 3 and 3' are provided on diameter axes perpendicular to the line connecting the pair of electrodes 2 and the tube axis of the measuring tube 1, respectively, and also serve as part of the outer casing. These magnetic poles 3, 3' have coils 4,
4' is wound.
外筐５，５′はコイル４，４′をも兼ねている。
また測定管１を流体から絶縁、および腐食防止す
るためにテフロン等で形成した絶縁ライナ６がが
設けられている。 The outer casings 5, 5' also serve as coils 4, 4'.
Further, an insulating liner 6 made of Teflon or the like is provided to insulate the measuring tube 1 from fluid and prevent corrosion.
また上述したように測定管１と外筐５とは接合
部７において外筐５の内壁面で接合されている。
流体を通す測定管１は非磁性体すなわちオーステ
ナイト系ステンレス鋼からなつており、外筐５は
電極２、磁極３、コイル４等を収納し、かつ電極
２から出てくる流量に比例した信号を取り出すた
めに図示していない端子箱を必要としている。 Further, as described above, the measuring tube 1 and the outer casing 5 are joined at the joint portion 7 on the inner wall surface of the outer casing 5.
The measuring tube 1 through which the fluid passes is made of a non-magnetic material, that is, austenitic stainless steel, and the outer casing 5 houses the electrode 2, the magnetic pole 3, the coil 4, etc., and transmits a signal proportional to the flow rate coming out from the electrode 2. A terminal box (not shown) is required to take it out.
このように従来の電磁流量計は複雑な構成を有
しており、この複雑な構成を有する電磁流量計を
安価に製作する方法の一つとして外筐５を鋳造品
として製作することが多い。 As described above, conventional electromagnetic flowmeters have complicated configurations, and as one method for inexpensively manufacturing electromagnetic flowmeters having such complicated configurations, the outer casing 5 is often manufactured as a cast product.
このさい鋳造材料としては強度上ダクタイル鋳
鉄を用いるのが一般的で、測定筐１と外筐５との
接合部７はアーク溶接によつて形成される。しか
し一般にオーステナイトステンレス鋼とダクタイ
ル鋳鉄とを直接アーク溶接により接合すると、溶
接金属やダクタイル鋳鉄側の溶接熱影響部に溶接
割れが生ずるという欠点があつた。このため従来
のアーク溶接による接合方法を用いる場合には第
２図に示したように外筐５のダクタイル鋳鉄を所
要寸法より小さく試作し、その部分にニツケル合
金８をガス溶接等により肉盛溶接するのが一般的
であつた。その後測定管１を挿入するために肉盛
溶接部を所望寸法に機械加工で施削する。 In this case, ductile cast iron is generally used as the casting material due to its strength, and the joint 7 between the measuring casing 1 and the outer casing 5 is formed by arc welding. However, in general, joining austenitic stainless steel and ductile cast iron by direct arc welding has the disadvantage that weld cracks occur in the weld metal and the weld heat affected zone on the ductile cast iron side. For this reason, when using the conventional joining method by arc welding, as shown in Figure 2, the ductile cast iron of the outer casing 5 is prototyped smaller than the required dimensions, and nickel alloy 8 is overlaid by gas welding etc. on that part. It was common to do so. Thereafter, in order to insert the measuring tube 1, the overlay weld is machined to a desired size.
ダクタイル鋳鉄製の外筐５とニツケル合金８と
オーステナイトステンレス鋼製の測定管１とを第
３図に示すようにアーク溶接により接合すると、
ニツケル合金８の効果により溶接割れの発生を減
少させた接合部７，７′を得ることができる。接
合部表面は絶縁ライナ６と面接触させるので機械
加工にて施削し仕上げた状態で使用する。 When the outer casing 5 made of ductile cast iron, the nickel alloy 8 and the measuring tube 1 made of austenitic stainless steel are joined by arc welding as shown in FIG.
Due to the effect of the nickel alloy 8, it is possible to obtain joints 7, 7' in which the occurrence of weld cracks is reduced. Since the joint surface is brought into surface contact with the insulating liner 6, it is used after being machined and finished.
しかしこのような従来の方法ではニツケル合金
８をダクタイル鋳鉄製の外筐５に肉盛溶接する作
業は狭隘部で円周方向の溶接となるため熟錬した
作業者によつても難かしく長時間を要していた。 However, in this conventional method, overlay welding of the nickel alloy 8 to the ductile cast iron outer casing 5 involves circumferential welding in a narrow area, which is difficult and takes a long time even for experienced workers. It required
また肉盛溶接部を本溶接するために所要寸法に
施削しなければならないという欠点を有してい
た。 Another drawback is that the overlay weld portion must be machined to the required dimensions in order to perform the final welding.
この発明の目的は電磁流量計の測定管と外筐と
の気密接合を形成するに当り溶接割れの発生がな
く、しかも信頼性の向上した電磁流量計の製造方
法を提供するにある。
It is an object of the present invention to provide a method of manufacturing an electromagnetic flowmeter that does not cause weld cracks when forming an airtight connection between a measuring tube and an outer casing of the electromagnetic flowmeter and has improved reliability.
この発明では上記目的を達成するために、オー
ステナイト系ステンレス鋼よりなる非磁性体の測
定管と、この測定管を収納するダクタイル鋳鉄よ
りなる円筒状の外筐とを前記外筐の内壁面上で接
合するに際し、前記外筐の接合箇所に環状溝を設
け、この環状溝内へ線状または粉末状のニツケル
を挿入し、高エネルギ密度熱源を照射して前記ニ
ツケルを溶融させて前記測定管と前記外筐とを接
合することを特徴としている。
In order to achieve the above object, in this invention, a non-magnetic measuring tube made of austenitic stainless steel and a cylindrical outer casing made of ductile cast iron that houses this measuring tube are arranged on the inner wall surface of the outer casing. When joining, an annular groove is provided at the joining location of the outer casing, a wire or powdered nickel is inserted into the annular groove, and a high energy density heat source is irradiated to melt the nickel and connect it to the measuring tube. It is characterized in that it is joined to the outer casing.
以下この発明を実施例に基づいて詳細に説明す
る。 The present invention will be described in detail below based on examples.
第４図はこの発明の一実施例に係る電磁流量計
の製造方法を説明するための図である。
FIG. 4 is a diagram for explaining a method of manufacturing an electromagnetic flowmeter according to an embodiment of the present invention.
なお第１図に示したと同一部分には同一符号を
付してその説明を省略する。 Note that the same parts as shown in FIG. 1 are given the same reference numerals and their explanations will be omitted.
この発明では測定管１と外筐５との接合に際し
てニツケルを用いる。このニツケルを溶融するに
あたりレーザ発振器２０により発生したレーザー
ビーム２１を反射鏡２２および集光レンズ２３を
用いて接合部１０および１０′に導き、測定管１
と外筐５の内壁面とを接合させる。 In this invention, nickel is used for joining the measuring tube 1 and the outer casing 5. To melt this nickel, a laser beam 21 generated by a laser oscillator 20 is guided to the joint parts 10 and 10' using a reflecting mirror 22 and a condensing lens 23, and the measuring tube 1
and the inner wall surface of the outer casing 5 are joined.
なおレーザ溶接時に溶接部を保護するために保
護カバ２４が設けられており、レーザ溶接時に溶
接部をシールドするためのシールドガス２５が保
護カバ２４内に導びかれるようになつている。 A protective cover 24 is provided to protect the welded portion during laser welding, and a shielding gas 25 for shielding the welded portion during laser welding is guided into the protective cover 24.
次に測定管１と外筐５との接合についてさらに
詳しく説明する。 Next, the connection between the measuring tube 1 and the outer casing 5 will be explained in more detail.
第５図および第６図は測定管１と外筐５との接
合部分を示した拡大断面図である。外筐５の測定
管１との接合個所には環状溝１１が設けられ、こ
の環状溝１１内にはニツケル線または粉末状のニ
ツケル１０が挿入されている。測定管１と外筐５
との接合にさいしてはこのニツケル線またニツケ
ル粉末１０をレーザ光により溶融して接合部１２
を形成する。 5 and 6 are enlarged cross-sectional views showing the joint portion between the measuring tube 1 and the outer casing 5. FIG. An annular groove 11 is provided at the joint of the outer casing 5 with the measuring tube 1, and a nickel wire or powdered nickel 10 is inserted into the annular groove 11. Measuring tube 1 and outer casing 5
When joining the nickel wire or nickel powder 10 with the laser beam, the nickel wire or the nickel powder 10 is melted with a laser beam to form the joint 12.
form.
ここで用いられるレーザ溶接は周知のように電
子ビーム溶接と同じようにエネルギー密度が高く
高速溶接ができるという特徴を有している。 As is well known, the laser welding used here has the characteristics of high energy density and high speed welding, similar to electron beam welding.
第４図に示すレーザ発振器２０により発振させ
たレーザービーム２１は反射鏡２２により角度を
変えられ、集光レンズ２３により集光されて接合
個所へ照射される。この時レーザービーム２１の
照射位置はニツケル線またはニツケル粉末１０上
にくるように調節される。レーザ溶接中には接合
部１２が酸化したり接合部に欠陥が発生すること
を防止するためと、溶接時のスパツタによる集光
レンズ２３の損傷を防止するために、ヘリウムガ
スまたはアルゴンガス等の不活性ガスをシールド
ガス２５として保護カバ２４内に供給し、接合部
を保護する。測定管１と外筐５とは図示していな
い回転装置に取り付けられ、溶接時には連続回転
させられる。 A laser beam 21 oscillated by a laser oscillator 20 shown in FIG. 4 has its angle changed by a reflecting mirror 22, is condensed by a condensing lens 23, and is irradiated onto the joint. At this time, the irradiation position of the laser beam 21 is adjusted so that it is on the nickel wire or nickel powder 10. During laser welding, helium gas, argon gas, etc. An inert gas is supplied as a shielding gas 25 into the protective cover 24 to protect the joint. The measuring tube 1 and the outer casing 5 are attached to a rotating device (not shown) and are continuously rotated during welding.
レーザービーム２１はその出力を第７図に示す
ように制御して照射する。すなわち所望の溶けこ
み深さが得られ出力P0に上昇するまでの時間T1
と出力P0が０になるまでの時間T3をとり、出力
の増減をゆるやかにして良好な溶接部を得るよう
にしている。 The laser beam 21 is irradiated with its output controlled as shown in FIG. In other words, the time T 1 until the desired penetration depth is obtained and the output rises to P 0
The time T 3 required for the output P 0 to reach 0 is taken, and the output is gradually increased or decreased in order to obtain a good welded part.
なお第７図に示されるT2は溶接時間を示し、
被溶接物が一回転する時間に対応する。このよう
な構成にすれば出力が急変することにより発生す
る溶接欠陥を除去することができる。 In addition, T 2 shown in Fig. 7 indicates welding time,
Corresponds to the time it takes for the workpiece to rotate once. With this configuration, it is possible to eliminate welding defects that occur due to sudden changes in output.
このようなレーザー溶接を用いることにより接
合部１２の金属組織はニツケルを含有した組織と
なり、溶接金属やダクタイル鋳鉄製の外筐５側の
熱影響部にも溶接割れの発生のない健全な溶接部
を得ることができる。 By using such laser welding, the metal structure of the joint part 12 becomes a structure containing nickel, and a sound weld part with no weld cracks is created in the weld metal and the heat affected zone on the side of the outer casing 5 made of ductile cast iron. can be obtained.
本発明者らの実験によれば接合部の直径が53
mm、第６図に示す接合部１２の必要溶け込み深さ
Ｈを3.5mmとした場合、レーザ出力2.5KW、レー
ザ溶接速度1000mm／m′n、集光レンズ２３の焦点
距離190mm、Heガスのシールド、被溶接物の連続
回転速度を6rpmとして溶接をおこない良好な結
果を得た。 According to experiments by the inventors, the diameter of the joint is 53
mm, when the required penetration depth H of the joint 12 shown in Fig. 6 is 3.5 mm, the laser output is 2.5 KW, the laser welding speed is 1000 mm/m'n, the focal length of the condenser lens 23 is 190 mm, and the shielding of He gas Good results were obtained by welding the workpiece at a continuous rotation speed of 6 rpm.
以上説明したようにこの発明によれば、測定管
と外筐との接合に環状溝を設けニツケル線または
ニツケル粉末を挿入してレーザ溶接により電磁流
量計を製造するようにしたので、ダクタイル鋳鉄
製の外筐へニツケル合金を肉盛溶接する困難な作
業を省略することができる。
As explained above, according to the present invention, an annular groove is provided at the joint between the measuring tube and the outer casing, a nickel wire or nickel powder is inserted, and an electromagnetic flowmeter is manufactured by laser welding. The difficult work of welding nickel alloy overlay onto the outer casing of the device can be omitted.
またダクタイル鋳鉄製の外筐へニツケル合金を
肉盛溶接したあとで機械加工工程を省略すること
ができる。しかもレーザ溶接の場合には電子ビー
ム溶接の場合と異り真空引きを実現するための時
間が不要となるため高能率な溶接が得られる。 Furthermore, the machining process can be omitted after overlay welding the nickel alloy to the ductile cast iron outer casing. Moreover, in the case of laser welding, unlike in the case of electron beam welding, there is no need for time to create a vacuum, so highly efficient welding can be achieved.
さらにまたレーザ溶接の場合には大気中溶接で
あるため電磁流量計のように形状が複雑で小口径
から大口径を有する製品いずれの場合にも使用で
きる。 Furthermore, in the case of laser welding, since welding is carried out in the atmosphere, it can be used for products with complex shapes, such as electromagnetic flowmeters, having small to large diameters.
このようにレーザ溶接によつて電磁流量計の測
定管と外筐とを接合するので高能率で信頼性の高
い電磁流量計を得ることができるという利点を有
する。 Since the measuring tube and the outer casing of the electromagnetic flowmeter are thus joined by laser welding, there is an advantage that a highly efficient and reliable electromagnetic flowmeter can be obtained.
第１図は従来の電磁流量計の構造を示す断面
図、第２図および第３図は従来の接合法を示した
断面図、第４図はこの発明の一実施例を説明する
ための図、第５図、第６図はこの発明による接合
部の状態を示した断面図、第７図は溶接時のレー
ザビームの出力変化を示した特性図である。
１……測定管、５……外筐、１０……ニツケル
線またはニツケル粉末、１１……環状溝、１２…
…接合部、２１……レーザービーム。
FIG. 1 is a sectional view showing the structure of a conventional electromagnetic flowmeter, FIGS. 2 and 3 are sectional views showing a conventional joining method, and FIG. 4 is a diagram illustrating an embodiment of the present invention. , FIG. 5, and FIG. 6 are cross-sectional views showing the state of the joint according to the present invention, and FIG. 7 is a characteristic diagram showing changes in laser beam output during welding. DESCRIPTION OF SYMBOLS 1... Measuring tube, 5... Outer casing, 10... Nickel wire or nickel powder, 11... Annular groove, 12...
...joint, 21...laser beam.
Claims (1)
性体の測定管と、この測定管を収納するダクタイ
ル鋳鉄よりなる円筒状の外筐と前記外筐の内壁面
上で接合するに際し、前記外筐の接合箇所に環状
溝をもうけ、この環状溝内へ線状または粉末状の
ニツケルを挿入し、高エネルギ密度熱源を照射し
て前記ニツケルを溶融させて前記測定管と前記外
筐とを接合することを特徴とする電磁流量計の製
造方法。1. When joining a non-magnetic measuring tube made of austenitic stainless steel to a cylindrical outer casing made of ductile cast iron that houses this measuring tube on the inner wall surface of the outer casing, a An annular groove is formed, a wire or powdered nickel is inserted into the annular groove, and a high energy density heat source is irradiated to melt the nickel to join the measuring tube and the outer casing. A method for manufacturing an electromagnetic flowmeter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16911382A JPH0229168B2 (en) | 1982-09-28 | 1982-09-28 | DENJIRYURYOKEINOSEIZOHOHO |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16911382A JPH0229168B2 (en) | 1982-09-28 | 1982-09-28 | DENJIRYURYOKEINOSEIZOHOHO |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5958318A JPS5958318A (en) | 1984-04-04 |
| JPH0229168B2 true JPH0229168B2 (en) | 1990-06-28 |
Family
ID=15880538
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16911382A Expired - Lifetime JPH0229168B2 (en) | 1982-09-28 | 1982-09-28 | DENJIRYURYOKEINOSEIZOHOHO |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0229168B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0718722B2 (en) * | 1987-05-22 | 1995-03-06 | 株式会社東芝 | Electromagnetic flowmeter detector and manufacturing method thereof |
| JPH0629687Y2 (en) * | 1988-01-06 | 1994-08-10 | 株式会社東芝 | Electromagnetic flowmeter detector |
| US6308882B1 (en) * | 1999-09-13 | 2001-10-30 | Dana Corporation | Method for joining ductile iron and steel |
| DE102008057755B4 (en) * | 2008-11-17 | 2015-12-17 | Krohne Ag | Magnetic-inductive flowmeter |
-
1982
- 1982-09-28 JP JP16911382A patent/JPH0229168B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5958318A (en) | 1984-04-04 |
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