JPS61172023A - Method for measuring residual stress-imparing depth - Google Patents
Method for measuring residual stress-imparing depthInfo
- Publication number
- JPS61172023A JPS61172023A JP1283085A JP1283085A JPS61172023A JP S61172023 A JPS61172023 A JP S61172023A JP 1283085 A JP1283085 A JP 1283085A JP 1283085 A JP1283085 A JP 1283085A JP S61172023 A JPS61172023 A JP S61172023A
- Authority
- JP
- Japan
- Prior art keywords
- residual stress
- strain
- depth
- peening treatment
- tube
- 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
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/20—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress
- G01L1/22—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress using resistance strain gauges
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Force Measurement Appropriate To Specific Purposes (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明シ、原子力用蒸気発生器管等に用いる管材の表面
にショットピーニング処理を施したさいの、残留応力付
与深さの測定方法に関するものである。[Detailed Description of the Invention] Industrial Field of Application The present invention relates to a method for measuring the depth of residual stress when shot peening is applied to the surface of a tube material used for a nuclear steam generator tube, etc. .
従来の技術
原子力用蒸気発生器管等に用いる管材の表面に応力腐食
割れが生ずるのを防止するため、該表面にショットピー
ニング処理を施し、圧ｍ残留応力を発生させる方法が打
撃われている。このとき、上記ショットピーニング処理
程度が過剰であると被ピーニング処理面と反対の面の引
張残留応力が過大となり、該表面に、粒界腐食等に起因
する亀裂が生じた場合、その亀裂が進展しゃすい状況と
なり、また逆にショットピーニング処理程度が不足であ
ると、被ピーニング処理面の残留応力層が全面腐食によ
り早期に除去されてしまう。従って製造ラインにおいて
は、管材の表面部に適度の深さの残留応力層を形成させ
、残留応力付与深さを迅速に測定し、Ｍｍ定の結果をフ
ィードバックして、ショットピーニングの処理条件設定
に供することが必要である。BACKGROUND OF THE INVENTION In order to prevent stress corrosion cracking from occurring on the surface of tube materials used in nuclear power steam generator tubes and the like, a method of subjecting the surface to a shot peening treatment to generate pressure m residual stress has been widely used. At this time, if the degree of shot peening is excessive, the tensile residual stress on the surface opposite to the surface to be peened will become excessive, and if a crack occurs on the surface due to intergranular corrosion, the crack will propagate. If the shot peening treatment is insufficient, the residual stress layer on the surface to be peened will be quickly removed due to general corrosion. Therefore, on the production line, a residual stress layer of an appropriate depth is formed on the surface of the pipe material, the depth of residual stress is quickly measured, and the Mm determination results are fed back to set the shot peening processing conditions. It is necessary to provide
従来、例えば管外表面部の残留応力付与深さを測定する
には、ショットピーニング処理を施した後の供試管につ
いて、管外表面すら、電解研磨により一定の深さずつ薄
層を除去していき、除去するごとにＸ線応力測定法で応
力を測定するか、あるいは管内周もしくは管外周から、
順次同心円拭に一定の深さずつ削っていき、削るごとに
それぞれ管外周もしくは管内周に貼着したひずみゲージ
でひずみ量を測定することにより、管外表面から管内表
面にわたっての残留応力分布を求め、該残留応力分布か
ら管外表面部の残留応力付与深さを求めていた。Conventionally, for example, in order to measure the depth of residual stress applied to the outer surface of a tube, a thin layer was removed to a certain depth even from the outer surface of the tube after shot peening by electropolishing. Either measure the stress using X-ray stress measurement each time it is removed, or from the inner or outer circumference of the pipe.
The residual stress distribution from the outer surface of the tube to the inner surface of the tube is determined by sequentially carving to a certain depth in concentric circles and measuring the amount of strain with a strain gauge attached to the outer circumference or inner circumference of the tube each time. The depth of residual stress applied to the outer surface of the tube was determined from the residual stress distribution.
発明の目的
しかしながら、上記いずれの方法を用いても、残留応力
付与深さを求めるには、ＶＨフットーニング処理を施し
た後の供試管を用い、かつ長時間を要するので、ショッ
トピーニング処理条件設定へのフィードバックが遅れ、
そのため良好な品質管理を行ないえないという欠点があ
った。本発明は、かかる欠点を解決することを目的とし
たものである。Purpose of the Invention However, with any of the above methods, determining the depth of residual stress requires using a test tube that has been subjected to VH foottone treatment and requires a long time, so shot peening treatment conditions must be set. feedback is delayed,
Therefore, there was a drawback that good quality control could not be carried out. The present invention aims to solve these drawbacks.
発明の構成
本発明は、ピーニング処理管材の、被ピーニング処理面
と反対の面に、ひずみゲージを貼着して、ピーニング処
理によって生じたひずみ量を検出し、該検出値にもとづ
いて、あらかじめ求めたひ□ずみ量と残留応力付与深さ
との関係から、被ピーニング処理面における残留応力付
与深さを求めることを要旨とする残留応力付与深さ測定
法である。Structure of the Invention The present invention detects the amount of strain caused by peening by attaching a strain gauge to the opposite surface of the peened pipe material, and calculates the amount of strain in advance based on the detected value. This is a residual stress application depth measurement method that aims to determine the residual stress application depth on the surface to be peened from the relationship between the amount of strain and the residual stress application depth.
以下に、本発明について詳細に説明する。The present invention will be explained in detail below.
第２図は管外表面にピーニング処理を施した後の管材の
断面において、管外表面から管内表面にわたっての残留
応力の生成状況を示す模式図である。外表面側の加工層
■では圧縮残留応力（８）、内表面側の非加工層０では
引張残留応力■が生じており、外表面側の加工層■の厚
さが、上記の管タト表面部の残留応力付与深さに相当す
る。FIG. 2 is a schematic diagram showing how residual stress is generated from the outer surface to the inner surface of the tube in a cross section of the tube material after the outer surface of the tube has been subjected to peening treatment. Compressive residual stress (8) occurs in the treated layer ■ on the outer surface side, and tensile residual stress ■ occurs in the untreated layer 0 on the inner surface side, and the thickness of the treated layer ■ on the outer surface side This corresponds to the depth at which residual stress is applied.
いま、管の肉厚をｔ１加工層の厚さをδとし、また加工
層において、
軸方向応力を σ、２、
円周方向応力を σｌ１１１
非加工層において、
軸方向応力を σ２７、 軸方向ひずみをｅ、２、円
周方向応力を０２０１円周方向ひずみをｅ２（Ｊ、とす
ると、応力の釣合条件より、次の（１ａ）式および（１
ｂ）式が成り立つ。Now, the wall thickness of the pipe is t1, the thickness of the processed layer is δ, and in the processed layer, the axial stress is σ, 2, the circumferential stress is σl111, and in the unprocessed layer, the axial stress is σ27, and the axial strain is Assuming that e is 2, the circumferential stress is 0201, and the circumferential strain is e2(J), then from the stress balance conditions, the following equations (1a) and (1
b) The formula holds true.
σ１．．δ＋σ２．（ｔ−δ）＝０・・・（１ａ）式σ
１ｏδ＋σｚ６（ｔ−６）＝０・・・（ｌｂ）式（１ａ
）式および（１ｂ）式において、（を−６）は非加工層
の厚さを表わす。σ1. ．． δ+σ2. (t-δ)=0...(1a) formula σ
1oδ+σz6(t-6)=0...(lb) Formula (1a
) and (1b), (-6) represents the thickness of the unprocessed layer.
また非加工層においては、応力とひずみとの間に、ヤン
グ率をＥ１ポアソン比をνとして、次の（２ａ）式およ
び（２ｂ）式の関係がある。In the unprocessed layer, there is a relationship between stress and strain as expressed by the following equations (2a) and (2b), where Young's modulus is E1 and Poisson's ratio is ν.
σ ” （”！Ｚ＋νｇｚ６ ）・・・（２ａ）式
％式％
従って、管内表面のひずみ、ｅ！Ｚ 、ｆ１２１ｊを測
定すれば、（２ａ）式および（２ｂ）式から非加工層に
おける応力σ！２およびσ２０が求められ、一方加工層
における応力σ１ｚＮ σ、０を測定することにより、
（ｌａ）式あるいは（１ｂ）式から加工層の厚さδを求
めることができる。すなわち、管内表面のひずみ εｚ
ｚ 、 ｅ’ａ６と、加工層における応力σ１ｚまたは
σ、θと、加工層の厚さδとの間に相関関係がある。σ ” (”!Z+νgz6 )...(2a) Formula % Formula % Therefore, the strain on the pipe inner surface, e! If Z and f121j are measured, the stress σ! in the unprocessed layer can be obtained from equations (2a) and (2b). 2 and σ20 are determined, while by measuring the stress σ1zN σ,0 in the processed layer,
The thickness δ of the processed layer can be determined from equation (la) or equation (1b). In other words, the strain on the pipe inner surface εz
There is a correlation between z, e'a6, the stress σ1z or σ, θ in the processed layer, and the thickness δ of the processed layer.
本発明は上記の相関関係を用いた残留応力付与深さの測
定方法であって、あらかじめ被処理管の材質・寸法別お
よびピー二／グ処理条件別に、加工層にあける応力を種
々変えてやりながら、管内表面のびずみε、２、ｅ□の
いずれか一方と、加工層の厚さδとの間の関係を求めて
おき、上記８２２、ｅ□のいずれか一方を検出すること
によって、加工層の厚さδ、すな□わち残留応力付与深
さを求める方法である。The present invention is a method for measuring the depth of applying residual stress using the above correlation, and the stress applied to the processed layer is varied in advance depending on the material and dimensions of the pipe to be treated and the peening treatment conditions. At the same time, the relationship between strain ε, 2, e□ on the pipe inner surface and the thickness δ of the processed layer is determined, and by detecting either of the above 822, e□, processing can be performed. This is a method for determining the layer thickness δ, that is, the depth to which residual stress is applied.
第１図は本発明に係る具体的な測定方法の一例を示す説
明図である。第１図において被処理管材（１）の外表面
にショット■を投射してピーニング処理を行なうにあた
り、ひずみゲージａ）を被ピーニング処理面と反対の面
、すなわち管内表面に貼着し、ピーニング処理を行ない
ながら、該ピーニング処理によって生じたひずみ量をひ
ずみ計（イ）で検出する。一方、ひずみ量と残留応力付
与深さとの関係をあらかじめ求めておき、上記ひずみ計
（２）で検出したひずみ量にもとすき、残留応力付与深
さを求める。FIG. 1 is an explanatory diagram showing an example of a specific measuring method according to the present invention. In Figure 1, when performing peening treatment by projecting shot (1) onto the outer surface of the pipe material to be treated (1), strain gauge a) is attached to the surface opposite to the surface to be peened, that is, the inner surface of the tube, and the peening treatment is carried out. While performing the peening process, the amount of strain caused by the peening process is detected using a strain meter (a). On the other hand, the relationship between the amount of strain and the depth of applying residual stress is determined in advance, and the depth of applying residual stress is determined using the amount of strain detected by the strain gauge (2).
実 施 例 以下、実施例にもとずいて更に詳細に説明する。Example Hereinafter, a more detailed explanation will be given based on examples.
まず、本発明の考え方の基礎になっている上記の方法、
すなわち管内表面のひずみと、加工層における応力とを
実測して加工層の厚さ、言い換えれば残留応力付与深さ
、を求める方法（以下簡易推定法という）について説明
する。First, the above method, which is the basis of the idea of the present invention,
That is, a method (hereinafter referred to as a simple estimation method) for determining the thickness of the processed layer, in other words, the depth of applying residual stress, by actually measuring the strain on the pipe inner surface and the stress in the processed layer will be explained.
第３図は、簡易推定法が、前記従来法と比較して、実用
上問題ない精度を有するかどうかを調べた結果を示す図
で、外径２２寵、肉厚１．２７ ｍで、第１表に示す化
学成分を有する原子力用蒸気発生゛容管に対し、直径３
５０〜５９０μのガラスピーズを用い、投射圧力２ｋｇ
／ｃＪ１投射ノズル数４本送管スピード８００ ｗｍ
／Ｗｉｎでシ冒ットピーニング処理を行なった場合の実
験結果である。FIG. 3 is a diagram showing the results of an investigation to see whether the simple estimation method has accuracy sufficient for practical use compared to the conventional method. For a nuclear steam generation vessel having the chemical composition shown in Table 1, a diameter of 3
Using 50-590μ glass beads, projection pressure 2kg
/cJ1 Number of projection nozzles: 4, pipe speed: 800 wm
These are the experimental results when the cut peening process was performed using /Win.
第 １ 表
第３図において、横軸は管外表面からの深さを、縦軸は
管外表面部の残留応力を示す。第３図中、実１！（ａ）
および破１ｆ！（ｂ）は簡易推定法にもとずき、ひずみ
ゲージを貼着して求めた管内表面のひずみと、Ｘ線応力
測定法により求めた管外表面部の残留応力とから、管外
表面部の残留応力付与深さを求め、図示したもので、実
線（ａ）は軸方向に関する測定値にもとすく結果であり
、破線（ｂ）は円周方向に関する測定値にもとずく結果
である。In Table 1 and Figure 3, the horizontal axis represents the depth from the outer surface of the tube, and the vertical axis represents the residual stress on the outer surface of the tube. In figure 3, fruit 1! (a)
And broken 1f! (b) is based on the simple estimation method, and is calculated from the strain on the inner surface of the tube determined by attaching a strain gauge and the residual stress on the outer surface of the tube determined by X-ray stress measurement. The depth of residual stress applied is determined and illustrated, where the solid line (a) is the result based on the measured value in the axial direction, and the broken line (b) is the result based on the measured value in the circumferential direction. .
また、実１１！ （ｃ）および破１！ （ｄ）は従来法
にもとすき、電解研磨により管外表面から一定の深さず
つ薄膜を除去していき、除去するごとにＸ線応力測定法
で残留応力を測定して、残留応力付与深さを求めたもの
で、実！（Ｃ）は実線（ａ）に対応する軸方向に関する
結果であり、破１！ （ｄ）は破！１（ｂ）に対応する
円周方向に関する結果である。Also, fruit 11! (c) and Break 1! (d) is similar to the conventional method; the thin film is removed from the outer surface of the tube by a certain depth by electrolytic polishing, and the residual stress is measured by X-ray stress measurement each time it is removed, and the residual stress is applied. I was looking for depth, and it's true! (C) is the result regarding the axial direction corresponding to the solid line (a), and it is broken 1! (d) is broken! 1(b) is the result regarding the circumferential direction.
第３図において、本簡易推定法にもとず（実線（＆）お
よび破＃Ｉ （ｂ）と、従来法にもとず（実１！（ｃ）
および破１！ （ｄ）とを比較すると、縦軸（Ｗ外表面
の残留応力）の値が０であるとｄの横軸（管外表面から
の深さ）の値、すなわち残留応力付与深′さは、本発明
の簡易推定法にもとすく場合若干小さくなるが、実用上
十分の精度を存することがわかる。In Fig. 3, the results are shown based on the present simple estimation method (solid line (&) and broken #I (b), and based on the conventional method (actual 1! (c)).
And break 1! Comparing with (d), if the value of the vertical axis (residual stress on the outer surface of W) is 0, the value of the horizontal axis (depth from the outer surface of the tube) of d, that is, the depth of applying residual stress is It can be seen that the simple estimation method of the present invention has sufficient accuracy for practical use, although it is slightly smaller.
次に、上記簡易推定法を用いて、本発明方法について説
明する。Next, the method of the present invention will be explained using the above-mentioned simple estimation method.
第４図は前記の原子力用蒸気発生器管に対し、直径３５
０〜５９０μのガラスピーズを用い、投射圧力２〜４
ｋｇ ｆ／ｃＪで、道管スピードを２５０〜８００鶴／
ｗｉｎの範囲で段階的に変え、ピーニング処理を行ない
、管内表面に貼着したひずみゲージによりひずみ量を検
出し、これと、ＸＩｌ応力測定法で求めた管外表面部の
応力とから、簡易推定法により残留応力付与深さを求め
、横軸を円周方向ひずみ量、縦軸を残留応力付与深さと
して表したものである。Figure 4 shows a diameter of 35 mm for the nuclear steam generator tube described above.
Using glass beads of 0 to 590μ, projection pressure of 2 to 4
kg f/cJ, pipe speed 250-800 Tsuru/
The amount of strain is detected by a strain gauge attached to the inner surface of the tube, and the stress on the outer surface of the tube determined by the XIl stress measurement method is used for simple estimation. The depth of residual stress is determined by the method, and the horizontal axis is the amount of strain in the circumferential direction, and the vertical axis is the depth of residual stress.
第４図において、実！Ｉ（ａ）は投射ノズル数４本、破
１！（ｂ）は同じく１本の場合である。第４図から、投
射ノズルの本数が異ると、ひずみ量と残留応力付与深さ
との関係は異るが、各々の場合について、管内表面のひ
ずみ量と残留応力付与深さとの間に一定の関係があるこ
とがわかる。In Figure 4, fruit! I(a) has 4 projection nozzles and 1 break! (b) is also the case of one piece. From Fig. 4, it can be seen that the relationship between the amount of strain and the depth of applying residual stress differs when the number of projection nozzles differs, but in each case, there is a constant relationship between the amount of strain on the inner surface of the pipe and the depth of applying residual stress. It turns out that there is a relationship.
従って、本発明方法によれば、管外表面にピーニング処
理を行なうさい、管内表面にひずみゲージを貼着しでお
き、前記ピーニング処理によって生じたひずみ量を検出
することにより、該検出値にもとすいて管外表面の残留
応力付与深さを求めることができる。Therefore, according to the method of the present invention, when performing peening treatment on the outer surface of the tube, a strain gauge is attached to the inner surface of the tube and the amount of strain caused by the peening treatment is detected, so that the detected value can also be applied to the peening treatment. The depth of residual stress applied to the outer surface of the tube can be determined as follows.
発明の詳細
な説明したように、本発明は、管外表面にピーニング処
理を行なうさい、管内表面に貼着したひずみゲージによ
りひずみ量を検出し、該検出値にもとずいて、あらかじ
め求めたひずみ量と残留応力付与深さとの関係から、被
ピーニング処理面の残留応力付与深さを求める方法であ
るため、ピーニング処理実施中に残留応力付与深さを把
握できるという利点がある。従って、必要に応じ、ピー
ニング処理条件を迅速にコントロールするととが可能で
、品質管理面における有用性は極めて大きい。As described in detail, the present invention detects the amount of strain using a strain gauge attached to the inner surface of the tube when performing peening treatment on the outer surface of the tube, and based on the detected value, calculates the amount of strain determined in advance. Since this method determines the depth of residual stress applied to the surface to be peened from the relationship between the amount of strain and the depth of residual stress applied, it has the advantage that the depth of residual stress applied can be grasped during the peening process. Therefore, it is possible to quickly control the peening treatment conditions as required, which is extremely useful in terms of quality control.
なお、以上の説明は、管外表面に対しピーニング処理す
る場合の測定方法について述べたが、逆に管内表面に対
しピーニング処理する場合においても、本発明方法が適
用可能であり、かつ管内表面に対しピーニング処理する
場合におけると同様の効果があることはもちろんである
。The above explanation has been about the measurement method when peening the outside surface of the pipe, but conversely, the method of the present invention is also applicable when peening the inside surface of the pipe. On the other hand, it goes without saying that the same effect as in the case of peening treatment can be obtained.
第１図は本発明に係る具体的な測定方法の一例を示す説
明図、第２図は残留応力の生成伏況を示す模式図、第３
図は管外表面からの深さと管外表面部の残留応力との関
係を示す線図、第４図は管内表面円周方向のひずみと残
留応力付与深さとの関係を示す線図である。
■・・・被処理材、２・・・シコット、３・・・ひずみ
ゲージ、４・・・ひずみ計、・５・・・加工層、 ６・
・・非加工層、７・・・引張残留応力、 ８・・・圧縮
残留応力。
出 願 人 住友金属工業株式会社
代理人弁理士 押 １）良 久曜姉
第 １ 図
′第２図
第３図
第４図
Ｉ肉物門用方肖ｔｂｆ）ｆＪｔFIG. 1 is an explanatory diagram showing an example of a specific measurement method according to the present invention, FIG. 2 is a schematic diagram showing the generation situation of residual stress, and FIG.
The figure is a diagram showing the relationship between the depth from the tube's outer surface and the residual stress on the tube's outer surface, and FIG. 4 is a diagram showing the relationship between the strain in the circumferential direction on the tube's inner surface and the depth to which residual stress is applied. ■... Material to be treated, 2... Cicotte, 3... Strain gauge, 4... Strain meter, 5... Processing layer, 6.
...Unprocessed layer, 7... Tensile residual stress, 8... Compressive residual stress. Applicant Sumitomo Metal Industries Co., Ltd. Patent Attorney 1) Hisayo Ryo 1 Figure 2 Figure 3 Figure 4
Claims (1)
に、ひずみゲージを貼着して、ピーニング処理によって
生じたひずみ量を検出し、該検出値にもとずいて、あら
かじめ求めたひずみ量と残留応力付与深さとの関係から
、被ピーニング処理面における残留応力付与深さを求め
ることを特徴とする残留応力付与深さ測定法。A strain gauge is attached to the opposite surface of the peened pipe to detect the amount of strain caused by the peening process, and based on the detected value, the amount of strain determined in advance and the remaining amount are determined. A residual stress application depth measuring method characterized by determining the residual stress application depth on a surface to be peened from the relationship with the stress application depth.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1283085A JPS61172023A (en) | 1985-01-25 | 1985-01-25 | Method for measuring residual stress-imparing depth |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1283085A JPS61172023A (en) | 1985-01-25 | 1985-01-25 | Method for measuring residual stress-imparing depth |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS61172023A true JPS61172023A (en) | 1986-08-02 |
Family
ID=11816292
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1283085A Pending JPS61172023A (en) | 1985-01-25 | 1985-01-25 | Method for measuring residual stress-imparing depth |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61172023A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009168562A (en) * | 2008-01-15 | 2009-07-30 | Fujitsu Ltd | Stress evaluating method using raman spectroscopy, and method of manufacturing semiconductor device |
| JP2011252811A (en) * | 2010-06-02 | 2011-12-15 | Ihi Corp | Residual stress measuring method |
-
1985
- 1985-01-25 JP JP1283085A patent/JPS61172023A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009168562A (en) * | 2008-01-15 | 2009-07-30 | Fujitsu Ltd | Stress evaluating method using raman spectroscopy, and method of manufacturing semiconductor device |
| JP2011252811A (en) * | 2010-06-02 | 2011-12-15 | Ihi Corp | Residual stress measuring method |
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