JP2005030891A

JP2005030891A - Surface non-destructive inspection apparatus and surface non-destructive inspection method

Info

Publication number: JP2005030891A
Application number: JP2003195778A
Authority: JP
Inventors: Tetsuo Aikawa; 徹郎相川
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 2003-07-11
Filing date: 2003-07-11
Publication date: 2005-02-03

Abstract

<P>PROBLEM TO BE SOLVED: To make performable an efficient inspection by non-destructively detecting a damage on the surface of a nozzle, or the like. <P>SOLUTION: A surface non-destructive inspection apparatus for inspecting an inspection surface non-destructively is provided with a distance measurement sensor for measuring the distance to the inspection surface, based on information obtained by photographing an inspection surface; a shifter for moving the distance measurement sensor to a position for photographing the inspection surface and further for scanning the distance measurement sensor along the inspection surface; a distance measuring apparatus for obtaining distance to the inspection surface, based on signals from the distance measurement sensor; scanning control information in the shifter; and an evaluation apparatus for detecting damage on the inspection surface, based on a shape image by creating the shape image for expressing the shape of the inspection surface, based on distance information to the inspection surface obtained by the distance measuring apparatus. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、発電設備などで使用されるノズルなどの表面に発生した損傷を非破壊で自動的に検査するための検査装置および検査方法に関する。
【０００２】
【従来の技術】
発電設備などで使用されている機器部品は、機能の安全性を維持するために定期的な点検が実施されている。前述した点検において、機器の安全性や性能に大きく影響を与える損傷を検出するために、機器を分解した後に外観や内部を検査する分解点検が実施されており、これは最も重要視される点検項目である。
【０００３】
従来のノズルに関する分解点検は、ノズル表面に発生した損傷の有無および損傷の寸法によって検査の合否を定めている。また、前検査は、検査員による目視にて実施されている。
【０００４】
【発明が解決しようとする課題】
上述した従来の検査員による目視検査では、検査員の熟練度などに起因して統一的な検査基準にて実施することは困難である。また、検査員の作業労力に頼っているため、生産性のある効率的な検査が提供できない。
【０００５】
本発明は上記従来技術の課題を解決するためになされたものであり、ノズルなどの表面に発生した損傷を画像処理にて非破壊的に検出し効率的な検査を行なうことのできる表面検査装置および表面検査方法を提供することを目的とする。
【０００６】
【課題を解決するための手段】
この発明は上記目的に沿うものであって、請求項１に記載の発明は、検査表面を非破壊的に検査する表面非破壊検査装置において、前記検査表面を撮影することによって得た情報に基づいて前記検査表面までの距離を計測する距離計測センサと、前記距離計測センサを、前記検査表面を撮影する位置まで移動させて、さらに前記距離計測センサを前記検査表面に沿って走査させる移動装置と、前記距離計測センサからの信号に基づいて前記検査表面までの距離を求める距離計測装置と、前記移動装置の走査制御情報と、前記距離計測装置で求めた前記検査表面までの距離情報とに基づいて、前記検査表面の形状を表す形状画像を作成しその形状画像に基づいて前記検査表面の損傷を検出する評価装置と、を有すること、を特徴とする。
【０００７】
また、請求項９に記載の発明は、側面を有する筒状の検査表面を非破壊的に検査する表面非破壊検査装置において、前記検査表面を撮影する撮像装置と、前記検査表面の側面から発した光を反射させて前記撮像装置に伝送するためにミラーと、前記撮像装置を検査位置まで移動させる移動装置と、前記撮像装置で得られた画像を、前記ミラーの形状と前記ミラーに映り込んだ形状に基づいて画像処理を施し平面展開画像を作成する検査表面展開装置と、前記検査表面展開装置で作成した平面展開画像に基づいて前記検査表面の損傷を検出する評価装置と、を有すること、を特徴とする。
【０００８】
また、請求項１５に記載の発明は、検査表面を非破壊的に検査する表面非破壊検査方法において、距離計測センサを、前記検査表面を撮影する位置まで移動させて、さらに前記距離計測センサを前記検査表面に沿って走査させる移動ステップと、前記距離計測センサによって前記検査表面を撮影する撮影ステップと、前記距離計測センサからの信号に基づいて前記検査表面までの距離を求める距離計測ステップと、前記移動装置の走査制御情報と、前記距離計測ステップで求めた前記検査表面までの距離情報とに基づいて、前記検査表面の形状を表す形状画像を作成しその形状画像に基づいて前記検査表面の損傷を検出する評価ステップと、を有すること、を特徴とする。
【０００９】
【発明の実施の形態】
以下、本発明に係わる実施の形態について、図面を参照して説明する。ここで，相互に共通または類似の部分には共通の符号を付して、重複説明は省略する。
図１は、本発明に係る表面非破壊検査装置の第１の実施の形態の全体概略構成図である。上下移動や前後／左右移動および旋回移動を有した移動装置２に取り付けられた距離計測センサ１は、予め記憶した移動情報を基に移動制御装置４によって制御された移動装置２により、ノズル１００の検査箇所である表面の検査位置まで移動し検査表面に沿って走査される。
【００１０】
距離計測センサ１は撮像装置（後述）を有し、その撮像装置でノズル１００の検査表面２００を撮影し、撮影した映像をアナログの電気信号として映像信号線１２を介して距離計測装置３へ伝送する。距離計測装置３では、距離計測センサ１から伝送されたアナログの映像信号（電気信号）をＡ／Ｄ変換器２５（図２等参照）でデジタルの画像データに変換した後、画像データに画像処理を施し、距離計測センサ１からノズル１００の検査表面２００までの距離を計測する。
【００１１】
距離計測センサ１と距離計測装置３の第１の具体的構成例を図２を参照して説明する。この例では、距離計測センサ１は、ノズル１００の検査表面２００をステレオ的に撮影できる２台の撮像装置２０２ａ／２０２ｂを備え、１本の映像信号線１２で伝送開始時間をずらし２台分の映像信号を距離計測装置３へ伝送するか、若しくは２本の映像信号線１２で各々の映像信号を距離計測装置３へ伝送する。
【００１２】
距離計測装置３は、１台または２台のＡ／Ｄ変換器２５、視差演算プロセッサ２０６、距離演算プロセッサ２０７を備える。距離計測センサ１から伝送される２台の撮影装置２０２ａ／２０２ｂのアナログの映像信号（電気信号）をＡ／Ｄ変換器２５でデジタルの画像データに変換し、視差演算プロセッサ２０６にて２枚の画像データ間で対応する各画素の関連性を求め、視差量を演算する。距離演算プロセッサ２０７では、視差演算プロセッサ２０６で演算した視差量に基づいて、距離計測センサ１から検査表面２００までの距離が演算される。
【００１３】
次に、距離計測センサ１と距離計測装置３の第２の具体的構成例を図３を参照して説明する。この例では、距離計測センサ１は、撮像装置３０２と光学装置３０３を有する。光学装置３０３は、撮像装置３０２の正面に配置した第２反射ミラー３０５と、第２反射ミラーの両側に配置した第１反射ミラー３０４ａ／３０４ｂを備えている。
【００１４】
第１反射ミラー３０４ａ／３０４ｂと第２反射ミラー３０５は、ノズル１００の検査表面２００から放たれた光を第１光路３０６ａと第２光路３０６ｂに沿って撮像装置へ伝達するように配置調整されており、また、第１光路３０６ａと第２光路３０６ｂを伝達してきた検査表面２００からの光は、撮像装置３０２の異なる位置へ入力される。
【００１５】
例えば撮像装置３０２が備えた受光素子（図示せず）が長方形型の場合、縦中央を境界として片側が第１光路３０６ａからの光を受光し、反対片側が第２光路３０６ｂからの光を受光するような構成である。これにて、単一の撮像装置３０２でステレオ的に検査表面２００を撮影することができ、距離計測センサ１の小型化が可能となる。
【００１６】
図３の距離計測装置３は、Ａ／Ｄ変換器２５、画像分割プロセッサ３１０、視差演算プロセッサ３１１、距離演算プロセッサ３１２を備える。距離計測センサ１から伝送される撮像装置３０２のアナログの映像信号（電気信号）はＡ／Ｄ変換器２５でデジタルの画像データに変換され、画像分割プロセッサ３１０にて距離計測センサ１の第１光路３０６ａと第２光路３０６ｂの光を受光した領域で画像データが分割される。視差演算プロセッサ３１１は、画像分割プロセッサ３１０で分割した画像データ間で対応する各画素の関連性を求め視差量を演算する。距離演算プロセッサ３１２では、視差演算プロセッサ３１１で演算した視差量に基づいて距離計測センサ１から検査表面２００までの距離が演算される。
【００１７】
次に、距離計測センサ１と距離計測装置３の第３の具体的構成例を図４を参照して説明する。この例では、距離計測センサ１は、ノズル１００の検査表面２００へ直線状の軌跡としてレーザ光を走査し照射するレーザ光照射装置４０３と、そのレーザ光が検査表面で反射した反射光を撮影する撮像装置４０２を備えている。レーザ光照射装置４０３は、レーザ光を発生させレーザ光をビーム状に絞り込む対物レンズを有したレーザ発振器４０４と、ビーム状のレーザ光を検査表面２００に直線状に走査させる可動式ミラー４０５を備えている。
【００１８】
図４の距離計測装置３は、Ａ／Ｄ変換器２５、画像処理プロセッサ４０９、距離演算装置を備えている。距離計測センサ１から伝送される撮像装置４０２のアナログの映像信号（電気信号）はＡ／Ｄ変換器２５でデジタルの画像データに変換され、画像処理プロセッサ４０９にて画像データへ２値化処理および細線化処理などの画像処理を施され、検査表面２００におけるレーザ光の反射領域が特定される。その後、距離演算プロセッサ４１０にて、画像処理プロセッサ４０９で特定したレーザ光の反射領域の座標値に基づいて距離計測センサ１から検査表面２００までの距離が演算される。
【００１９】
次に、距離計測センサ１と距離計測装置３の第４の具体的構成例を図５を参照して説明する。この例では、距離計測センサ１は、ノズル１００の検査表面２００へ格子状にレーザ光を照射するレーザ光照射装置５０３と、そのレーザ光が検査表面２００で反射した反射光を撮影する撮像装置５０２を備えている。レーザ光照射装置５０３は、レーザ光を発生させレーザ光をビーム状に絞り込む対物レンズを有したレーザ発振器５０４と、ビーム状のレーザ光を格子状に偏光する偏光レンズ５０５を備えている。偏光レンズ５０５は，例えば複合円筒レンズである。
【００２０】
図５の距離計測装置３は、Ａ／Ｄ変換器２５、画像処理プロセッサ５０９、距離演算プロセッサ５１０を備えている。距離計測センサ１から伝送される撮像装置５０２のアナログの映像信号（電気信号）はＡ／Ｄ変換器２５でデジタルの画像データに変換され、画像処理プロセッサ５０９にて画像データへ２値化処理および縮短化処理などの画像処理を施され、検査表面２００におけるレーザ光の反射領域が特定される。その後、距離演算プロセッサ５１０にて画像処理プロセッサ５０９で特定したレーザ光の反射領域の座標値に基づいて距離計測センサ１から検査表面２００までの距離が演算される。
【００２１】
図１において、距離計測装置３で求めた距離計測センサ１からノズル１００の検査表面２００までの距離データは、距離信号線１０を介して評価装置５へ伝送され、また、移動装置２の走査に関する制御情報は、移動制御装置４によって制御信号線１１を介して評価装置５へ伝送される。
【００２２】
評価装置５は、例えば図６に示すように、表面形状画像作成装置６００、検査基準作成装置６０１、判定装置６０２、基準形状記録装置６０３を備えており、ノズル１００の検査表面２００に発生した損傷を検出する。
【００２３】
距離計測装置３から伝送される距離データと移動制御装置４から伝送される走査制御情報は、それぞれ、距離信号線１０および制御信号栓１１を通して表面形状画像作成装置６００へ入力される。表面形状画像作成装置６００は、移動装置２の走査に合わせて距離計測センサ１が計測した距離データを、移動制御装置４から伝送された走査制御情報を基に連結結合することで検査表面２００の形状を表す２次元の形状画像を作成する。表面形状画像作成装置６００にて作成された形状画像は、画像を構成する各画素の値が距離に応じた値を表している。
【００２４】
図１では、移動装置２にて距離計測センサ１を移動させ検査表面２００に沿って走査する構成であるが、移動装置２にてノズル１００を移動させ、距離計測センサ１を検査表面２００に沿って走査する構成でもよい。
【００２５】
前記構成では、表面形状画像作成装置６００で形状画像を作成する際に、距離計測センサ１とノズル１００の位置関係が既知でなければならないが、人間によって手動でノズル１００を検査位置に設置する場合、設置誤差が発生する。表面形状画像作成装置６００は、距離データにおいて同一の表面箇所を計測した重複する距離データ間の差分を演算し、差分が最小値となり得る補正値を求めることで設置誤差などに起因する計測精度の低下を抑制することが可能である。
【００２６】
基準形状記録装置６０３には、予め正常な検査表面の形状である基準形状を記憶しておき、判定装置６０２は、表面形状画像作成装置６００にて作成した形状画像と基準形状記録装置６０３に記録した基準形状を比較し、検査表面２００に発生した損傷の度合いを求め、求めた損傷の度合いによって検査の合否を判定する。
【００２７】
また、検査基準作成装置６０１は、検査の合否を判定する基準を過去の検査結果や補修実績などから作成する。例えば、ノズル１００にユニークな識別番号がある場合、図１の入力装置９にて識別番号を入力し、入力した識別番号を基に過去の検査結果を記録した検査結果記録装置７から過去の検査結果や補修実績などを参照し、定めた基準に従って検査の合否判定の基準を作成する。評価装置５の検査結果は、検査信号線３０を介して表示装置６および検査結果記録装置７に送信され、検査結果の表示や検査結果が記録保存される。
【００２８】
検査報告書作成装置８では、検査結果記録装置７に記録保存された過去の検査結果から、検査結果や検査報告書として必要な情報を参照し、予め定めたフォーマットの検査報告書を自動で作成することもできる。
【００２９】
次に、本発明に係る表面非破壊検査装置の第２の実施の形態を説明する。図７は、第２の実施の形態に係わる表面非破壊検査装置の全体概略構成図である。上下移動や前後／左右移動および旋回移動を有した移動装置２に取り付けられた撮像装置７０１は、予め記憶した移動情報を基に移動制御装置４によって制御された移動装置２により、ノズル１００の上部へ移動される。
【００３０】
図８は、検査体の使用用途から考えられる検査表面を図示したものである。図８においてノズル１００の検査表面は、筒状をした検査体の開口部上面にあたる上部検査表面８０１と、側面にあたる外側検査表面８０２および内側検査表面８０３である。この実施の形態では、検査体であるノズル１００の上部に移動した撮像装置７０１にて、図８に示した上部検査表面８０１とともに外側検査表面８０２および内側検査表面８０３を撮影するためのミラー７１０を備えている。ミラー７１０は、外側検査表面８０２から放たれた光を屈折（反射）させるための外面ミラーと、内側検査表面８０３から放たれた光を屈折（反射）させるための内面ミラーから構成される。
【００３１】
外面ミラーの一例を図９を参照して説明する。外面ミラー９０１は、筒型をしたノズル１００の側面にあたる外側検査表面８０２の外側に環状に配置され、外側検査表面８０２から放たれた光を屈折（反射）させ上部の撮像装置７０１へ導くものである。外側検査表面８０２から放たれた光は外面ミラー９０１の鏡面部９０４へ放射され、鏡面部９０４にて上部の撮像装置７０１の方向へ屈折（反射）され撮像装置７０１へ入力される。
【００３２】
また、撮像装置７０１が照明装置を備えている場合、照明装置は外面ミラー９０１の鏡面部９０４へ光を照射し、照射された光は鏡面部９０４にてノズル１００の外側検査表面８０２の方向に屈折（反射）され、屈折（反射）された光にて外側検査表面８０２が照らされる。外面ミラー９０１の鏡面部９０４の形状としては、検査体であるノズル１００の形状に合わせた形状が望ましく、例えばノズル１００が円筒形の場合には円錐型凹面が望ましい。
【００３３】
内面ミラーの一例を図１０を参照して説明する。内面ミラー１００１は、筒型をしたノズル１００の内側面にあたる内側検査表面８０３から放たれた光を屈折（反射）させ上部の撮像装置７０１へ導くものである。内側検査表面８０３から放たれた光は内面ミラー１００１の鏡面部１００４へ放射され、鏡面部１００４にて上部の撮像装置７０１の方向へ屈折（反射）され撮像装置７０１へ入力される。
【００３４】
また、撮像装置７０１が照明装置を備えている場合、照明装置は内面ミラー１００１の鏡面部１００４へ光を照射し、照射された光は鏡面部１００４にてノズル１００の内側検査表面８０３の方向に屈折（反射）され、屈折（反射）された光にて内側検査表面８０３が照らされる。内面ミラー１００１の鏡面部１００４の形状としては、検査体であるノズル１００の形状に合わせた形状が望ましく、例えばノズル１００が円筒形の場合には円錐型凸面が望ましい。
【００３５】
外面ミラー９０１と内面ミラー１００１を配設したノズル１００を上部から撮影した撮像装置７０１で得られる画像データには、図８に示した上部検査表面８０１と外側検査表面８０２および内側検査表面８０３が写像されており、撮像装置７０１は、撮影した画像データを検査表面展開装置へ送信する。
【００３６】
図７で、検査表面展開装置７０３は、撮像装置７０１から送信された画像データに画像処理を施すことで、画像データに映り込んだ上部検査表面８０１と外側検査表面８０２および内側検査表面８０３の領域を判断し抽出する。次に、画像データから判断抽出した上部検査表面８０１の領域を、画像データに映り込んだ形状とノズル１００の形状を基に座標変換し平面の上部検査表面展開画像を作成する。
【００３７】
また、画像データから判断抽出した外側検査表面８０２と内側検査表面８０３の領域についても、画像データに映り込んだ形状とノズル１００の形状およびミラー９０１、１００１の形状を基に座標変換し、平面の外側検査表面展開画像と内側検査表面展開画像を作成する。前展開画像を作成することで、各々の検査箇所で異なる検査分解能を統一化することができるとともに、損傷の寸法計測などが適切に評価できる。これにより、検査精度の低下を抑制することができる。
【００３８】
評価装置７０４では、検査表面展開装置７０３にて作成された展開画像に画像処理を施しノズル１００の表面に発生した損傷を自動で認識し検査する。損傷を自動で求めるための画像処理の一例としては、まず損傷の輪郭線を求めるために微分処理を施し、次に微分成分の大きさがあるしきい値以上の領域を抽出する２値化処理を行なう。２値化処理にて抽出した結果は、損傷の輪郭線であるため輪郭線で囲まれた領域を損傷領域とする閉領域埋込み処理を行なう。閉領域埋込みにて抽出した領域の面積があるしきい値以上を選択するノイズ除去処理を実行し、これまでの処理にて抽出された領域が損傷となる。
【００３９】
評価装置７０４でノズル１００の外観を自動で検査した結果は、各展開画像に自動で認識した損傷の領域の色を変えてオーバーレイ表示し、人が視覚的に理解しやすい情報で表示装置６に出力され、前表示とともに合否判定結果や損傷の寸法情報なども同時に表示装置６に出力される。また、評価装置７０４の検査結果は、撮像装置７０１の画像データ、検査表面展開装置で作成された展開画像などの検査過程情報とともに検査結果記録装置７に記録保存される。
【００４０】
検査報告書作成装置８では、検査結果記録装置７に記録保存された過去の検査結果から、検査結果や検査報告書として必要な情報を参照し、予め定めたフォーマットの検査報告書を自動で作成することもできる。
【００４１】
【発明の効果】
以上説明したように、本発明によれば、発電設備などで使用されるノズルなどの表面に発生した損傷を非破壊で自動に２次元的または３次元的に検査できることから、検査員の熟練度に依存することなく、統一的な検査基準で効率的に検査を行なうことができる。
【図面の簡単な説明】
【図１】本発明に係る表面非破壊検査装置の第１の実施の形態を示す全体ブロック図。
【図２】図１の距離計測センサおよび距離計測装置の第１の具体例を示すブロック図。
【図３】図１の距離計測センサおよび距離計測装置の第２の具体例を示すブロック図。
【図４】図１の距離計測センサおよび距離計測装置の第３の具体例を示すブロック図。
【図５】図１の距離計測センサおよび距離計測装置の第４の具体例を示すブロック図。
【図６】図１の評価装置の具体例を示すブロック図。
【図７】本発明に係る表面非破壊検査装置の第２の実施の形態を示す全体ブロック図。
【図８】図７のノズルを拡大して示す部分縦断面図。
【図９】図７の撮像装置およびノズルの付近の具体例を示す模式的部分縦断面図。
【図１０】図７の撮像装置およびノズルの付近の、図９とは異なる具体例を示す模式的部分縦断面図。
【符号の説明】
１…距離計測センサ、２…移動装置、３…距離計測装置、４…移動制御装置、５…評価装置、６…表示装置、７…検査結果記録装置、８…検査報告書作成装置、９…入力装置、１０…距離信号線、１１…制御信号線、１２…映像信号線、２５…Ａ／Ｄ変換器、３０…検査信号線、１００…ノズル、２００…検査表面、２０２ａ，２０２ｂ…撮像装置、２０６…視差演算プロセッサ、２０７…距離演算プロセッサ、３０２…撮像装置、３０４ａ，３０４ｂ…第１反射ミラー、３０５…第２反射ミラー、３０６ａ…第１光路、３０６ｂ…第２光路、３１０…画像分割プロセッサ、３１１…視差演算プロセッサ、３１２…距離演算プロセッサ、４０２撮像装置、４０３レーザ光照射装置、４０４レーザ発振器、４０５…可動式ミラー、４０９…画像処理プロセッサ、４１０…距離演算プロセッサ、５０２…撮像装置、５０４…レーザ発振器、５０５…偏光レンズ、５０９…画像処理プロセッサ、５１０…距離演算プロセッサ、６００…表面形状画像作成装置、６０１…検査基準作成装置、６０２…判定装置、６０３…基準形状記録装置、７０１…撮像装置、７０３…検査表面展開装置、７０４…評価装置、７１０…ミラー。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an inspection apparatus and an inspection method for automatically inspecting damage generated on the surface of a nozzle or the like used in a power generation facility or the like in a nondestructive manner.
[0002]
[Prior art]
Equipment parts used in power generation facilities and the like are regularly inspected to maintain functional safety. In the above-mentioned inspections, in order to detect damage that greatly affects the safety and performance of the equipment, an overhaul inspection is performed to inspect the appearance and interior after disassembling the equipment, which is the most important inspection. It is an item.
[0003]
In the overhaul inspection related to the conventional nozzle, the pass / fail of the inspection is determined by the presence or absence of damage occurring on the nozzle surface and the size of the damage. The pre-inspection is performed visually by an inspector.
[0004]
[Problems to be solved by the invention]
The above-described visual inspection by the conventional inspector is difficult to carry out according to a uniform inspection standard due to the skill level of the inspector. Also, because it relies on the labor of the inspector, it cannot provide a productive and efficient inspection.
[0005]
The present invention has been made in order to solve the above-described problems of the prior art, and is a surface inspection apparatus capable of nondestructively detecting damage generated on the surface of a nozzle or the like by image processing and performing an efficient inspection. And it aims at providing the surface inspection method.
[0006]
[Means for Solving the Problems]
The invention according to the first aspect is based on information obtained by photographing the inspection surface in a surface nondestructive inspection apparatus for nondestructively inspecting the inspection surface. A distance measuring sensor that measures the distance to the inspection surface, a moving device that moves the distance measuring sensor to a position where the inspection surface is imaged, and further scans the distance measuring sensor along the inspection surface; Based on a distance measuring device that obtains a distance to the inspection surface based on a signal from the distance measuring sensor, scanning control information of the moving device, and distance information to the inspection surface obtained by the distance measuring device. And an evaluation device that creates a shape image representing the shape of the inspection surface and detects damage to the inspection surface based on the shape image.
[0007]
According to a ninth aspect of the present invention, there is provided a surface nondestructive inspection apparatus for nondestructively inspecting a cylindrical inspection surface having a side surface, and an imaging device for photographing the inspection surface and a side surface of the inspection surface. A mirror for reflecting the transmitted light to be transmitted to the imaging device, a moving device for moving the imaging device to an inspection position, and an image obtained by the imaging device reflected on the shape of the mirror and the mirror An inspection surface development device that performs image processing based on the shape and creates a flat development image, and an evaluation device that detects damage on the inspection surface based on the flat development image created by the inspection surface development device. It is characterized by.
[0008]
The invention according to claim 15 is the surface non-destructive inspection method for non-destructively inspecting the inspection surface. The distance measurement sensor is moved to a position where the inspection surface is photographed, and the distance measurement sensor is further moved. A movement step of scanning along the inspection surface, an imaging step of photographing the inspection surface by the distance measurement sensor, and a distance measurement step of obtaining a distance to the inspection surface based on a signal from the distance measurement sensor; Based on the scanning control information of the moving device and the distance information to the inspection surface obtained in the distance measurement step, a shape image representing the shape of the inspection surface is created and the inspection surface of the inspection surface is generated based on the shape image. And an evaluation step for detecting damage.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments according to the present invention will be described below with reference to the drawings. Here, a common code | symbol is attached | subjected to a mutually common or similar part, and duplication description is abbreviate | omitted.
FIG. 1 is an overall schematic configuration diagram of a first embodiment of a surface nondestructive inspection apparatus according to the present invention. The distance measuring sensor 1 attached to the moving device 2 having vertical movement, front / rear / left / right movement, and turning movement moves the nozzle 100 by the moving device 2 controlled by the movement control device 4 based on the movement information stored in advance. It moves to the inspection position on the surface that is the inspection location and is scanned along the inspection surface.
[0010]
The distance measuring sensor 1 has an imaging device (described later). The imaging device captures the inspection surface 200 of the nozzle 100 and transmits the captured image to the distance measuring device 3 via the video signal line 12 as an analog electric signal. To do. In the distance measuring device 3, an analog video signal (electrical signal) transmitted from the distance measuring sensor 1 is converted into digital image data by an A / D converter 25 (see FIG. 2 and the like), and then image processing is performed on the image data. The distance from the distance measuring sensor 1 to the inspection surface 200 of the nozzle 100 is measured.
[0011]
A first specific configuration example of the distance measurement sensor 1 and the distance measurement device 3 will be described with reference to FIG. In this example, the distance measuring sensor 1 includes two imaging devices 202a / 202b capable of photographing the inspection surface 200 of the nozzle 100 in a stereo manner, and the transmission start time is shifted by one video signal line 12 for two units. The video signal is transmitted to the distance measuring device 3, or each video signal is transmitted to the distance measuring device 3 through the two video signal lines 12.
[0012]
The distance measuring device 3 includes one or two A / D converters 25, a parallax calculation processor 206, and a distance calculation processor 207. The analog video signals (electrical signals) of the two imaging devices 202a / 202b transmitted from the distance measuring sensor 1 are converted into digital image data by the A / D converter 25, and two images are processed by the parallax calculation processor 206. The relevance of each pixel corresponding between image data is calculated | required, and the amount of parallax is calculated. The distance calculation processor 207 calculates the distance from the distance measurement sensor 1 to the inspection surface 200 based on the amount of parallax calculated by the parallax calculation processor 206.
[0013]
Next, a second specific configuration example of the distance measurement sensor 1 and the distance measurement device 3 will be described with reference to FIG. In this example, the distance measurement sensor 1 includes an imaging device 302 and an optical device 303. The optical device 303 includes a second reflecting mirror 305 disposed in front of the imaging device 302, and first reflecting mirrors 304a / 304b disposed on both sides of the second reflecting mirror.
[0014]
The first reflecting mirror 304a / 304b and the second reflecting mirror 305 are arranged and adjusted so as to transmit the light emitted from the inspection surface 200 of the nozzle 100 to the imaging device along the first optical path 306a and the second optical path 306b. In addition, light from the inspection surface 200 transmitted through the first optical path 306 a and the second optical path 306 b is input to different positions of the imaging device 302.
[0015]
For example, when the light receiving element (not shown) included in the imaging device 302 is rectangular, one side receives light from the first optical path 306a with the vertical center as a boundary, and the other side receives light from the second optical path 306b. It is the composition which does. Thus, the inspection surface 200 can be imaged in a stereo manner with the single imaging device 302, and the distance measuring sensor 1 can be downsized.
[0016]
3 includes an A / D converter 25, an image division processor 310, a parallax calculation processor 311 and a distance calculation processor 312. An analog video signal (electrical signal) of the imaging device 302 transmitted from the distance measurement sensor 1 is converted into digital image data by the A / D converter 25, and the first optical path of the distance measurement sensor 1 is converted by the image division processor 310. The image data is divided in the area where the light beams 306a and 306b are received. The parallax calculation processor 311 calculates the amount of parallax by obtaining the relevance of corresponding pixels between the image data divided by the image division processor 310. The distance calculation processor 312 calculates the distance from the distance measurement sensor 1 to the inspection surface 200 based on the parallax amount calculated by the parallax calculation processor 311.
[0017]
Next, a third specific configuration example of the distance measurement sensor 1 and the distance measurement device 3 will be described with reference to FIG. In this example, the distance measuring sensor 1 captures a laser beam irradiation device 403 that scans and irradiates a laser beam as a linear locus on the inspection surface 200 of the nozzle 100 and reflected light that is reflected by the inspection surface. An imaging device 402 is provided. The laser light irradiation device 403 includes a laser oscillator 404 having an objective lens that generates laser light and narrows the laser light into a beam, and a movable mirror 405 that linearly scans the inspection surface 200 with the beam-shaped laser light. ing.
[0018]
4 includes an A / D converter 25, an image processor 409, and a distance calculation device. An analog video signal (electrical signal) of the imaging device 402 transmitted from the distance measuring sensor 1 is converted into digital image data by the A / D converter 25, and binarized into image data by the image processor 409. Image processing such as thinning processing is performed, and the reflection region of the laser beam on the inspection surface 200 is specified. Thereafter, the distance calculation processor 410 calculates the distance from the distance measurement sensor 1 to the inspection surface 200 based on the coordinate value of the reflection region of the laser light specified by the image processing processor 409.
[0019]
Next, a fourth specific configuration example of the distance measurement sensor 1 and the distance measurement device 3 will be described with reference to FIG. In this example, the distance measuring sensor 1 includes a laser light irradiation device 503 that irradiates the inspection surface 200 of the nozzle 100 with a laser beam in a lattice shape, and an imaging device 502 that captures reflected light reflected by the inspection surface 200. It has. The laser light irradiation device 503 includes a laser oscillator 504 having an objective lens that generates laser light and narrows the laser light into a beam shape, and a polarizing lens 505 that polarizes the beam-like laser light in a lattice shape. The polarizing lens 505 is a compound cylindrical lens, for example.
[0020]
The distance measuring device 3 in FIG. 5 includes an A / D converter 25, an image processing processor 509, and a distance calculation processor 510. An analog video signal (electrical signal) of the imaging device 502 transmitted from the distance measuring sensor 1 is converted into digital image data by the A / D converter 25, and binarized into image data by the image processor 509. Image processing such as shortening processing is performed, and the reflection region of the laser beam on the inspection surface 200 is specified. Thereafter, the distance calculation processor 510 calculates the distance from the distance measurement sensor 1 to the inspection surface 200 based on the coordinate value of the reflection region of the laser light specified by the image processing processor 509.
[0021]
In FIG. 1, distance data from the distance measurement sensor 1 obtained by the distance measurement device 3 to the inspection surface 200 of the nozzle 100 is transmitted to the evaluation device 5 via the distance signal line 10, and also relates to scanning of the moving device 2. The control information is transmitted to the evaluation device 5 via the control signal line 11 by the movement control device 4.
[0022]
For example, as shown in FIG. 6, the evaluation device 5 includes a surface shape image creation device 600, an inspection reference creation device 601, a determination device 602, and a reference shape recording device 603, and damage generated on the inspection surface 200 of the nozzle 100. Is detected.
[0023]
The distance data transmitted from the distance measuring device 3 and the scanning control information transmitted from the movement control device 4 are input to the surface shape image creating device 600 through the distance signal line 10 and the control signal plug 11 respectively. The surface shape image creating apparatus 600 connects the distance data measured by the distance measuring sensor 1 in accordance with the scanning of the moving device 2 based on the scanning control information transmitted from the moving control device 4 to thereby connect the inspection surface 200. A two-dimensional shape image representing the shape is created. In the shape image created by the surface shape image creation device 600, the value of each pixel constituting the image represents a value corresponding to the distance.
[0024]
In FIG. 1, the distance measuring sensor 1 is moved by the moving device 2 and scanned along the inspection surface 200. However, the nozzle 100 is moved by the moving device 2 and the distance measuring sensor 1 is moved along the inspection surface 200. May be configured to scan.
[0025]
In the above configuration, when the shape image is created by the surface shape image creation device 600, the positional relationship between the distance measurement sensor 1 and the nozzle 100 must be known. However, when the nozzle 100 is manually installed at the inspection position by a human being. Installation error occurs. The surface shape image creating apparatus 600 calculates a difference between overlapping distance data obtained by measuring the same surface portion in the distance data, and obtains a correction value that can minimize the difference, thereby obtaining a measurement accuracy due to an installation error or the like. It is possible to suppress the decrease.
[0026]
The reference shape recording device 603 stores a reference shape that is a normal inspection surface shape in advance, and the determination device 602 records the shape image created by the surface shape image creation device 600 and the reference shape recording device 603. The reference shapes thus obtained are compared, the degree of damage generated on the inspection surface 200 is obtained, and the pass / fail of the inspection is determined based on the obtained degree of damage.
[0027]
Further, the inspection standard creation device 601 creates a standard for determining whether or not the inspection is successful from past inspection results and repair results. For example, when the nozzle 100 has a unique identification number, the identification number is input by the input device 9 of FIG. 1, and the past inspection result is recorded from the inspection result recording device 7 that records the past inspection result based on the input identification number. Refer to the results and repair results, and create a criterion for pass / fail inspection according to the established criteria. The inspection result of the evaluation device 5 is transmitted to the display device 6 and the inspection result recording device 7 through the inspection signal line 30, and the display of the inspection result and the inspection result are recorded and stored.
[0028]
The inspection report creation device 8 automatically creates an inspection report in a predetermined format by referring to information necessary as an inspection result or an inspection report from past inspection results recorded and stored in the inspection result recording device 7. You can also
[0029]
Next, a second embodiment of the surface nondestructive inspection apparatus according to the present invention will be described. FIG. 7 is an overall schematic configuration diagram of the surface nondestructive inspection apparatus according to the second embodiment. The imaging device 701 attached to the moving device 2 having the vertical movement, the front / back / left / right movement, and the turning movement moves the upper portion of the nozzle 100 by the moving device 2 controlled by the movement control device 4 based on the movement information stored in advance. Moved to.
[0030]
FIG. 8 illustrates an inspection surface that can be considered from the intended use of the inspection object. In FIG. 8, the inspection surfaces of the nozzle 100 are an upper inspection surface 801 corresponding to the upper surface of the opening of the cylindrical inspection object, and an outer inspection surface 802 and an inner inspection surface 803 corresponding to the side surfaces. In this embodiment, a mirror 710 for imaging the outer inspection surface 802 and the inner inspection surface 803 together with the upper inspection surface 801 shown in FIG. I have. The mirror 710 includes an outer mirror for refracting (reflecting) the light emitted from the outer inspection surface 802 and an inner mirror for refracting (reflecting) the light emitted from the inner inspection surface 803.
[0031]
An example of the outer mirror will be described with reference to FIG. The outer mirror 901 is annularly arranged outside the outer inspection surface 802 corresponding to the side surface of the cylindrical nozzle 100, and refracts (reflects) light emitted from the outer inspection surface 802 and guides it to the upper imaging device 701. is there. The light emitted from the outer inspection surface 802 is emitted to the mirror surface portion 904 of the outer mirror 901, and is refracted (reflected) toward the upper imaging device 701 by the mirror surface portion 904 and input to the imaging device 701.
[0032]
When the imaging device 701 includes an illumination device, the illumination device irradiates light to the mirror surface portion 904 of the outer mirror 901, and the irradiated light is directed to the outer inspection surface 802 of the nozzle 100 at the mirror surface portion 904. The outer inspection surface 802 is illuminated with the refracted (reflected) and refracted (reflected) light. The shape of the mirror surface portion 904 of the outer mirror 901 is preferably a shape that matches the shape of the nozzle 100 that is an inspection object. For example, when the nozzle 100 is cylindrical, a conical concave surface is desirable.
[0033]
An example of the inner surface mirror will be described with reference to FIG. The inner mirror 1001 refracts (reflects) light emitted from the inner inspection surface 803 corresponding to the inner surface of the cylindrical nozzle 100 and guides it to the upper imaging device 701. The light emitted from the inner inspection surface 803 is emitted to the mirror surface portion 1004 of the inner surface mirror 1001, and is refracted (reflected) toward the upper imaging device 701 by the mirror surface portion 1004 and input to the imaging device 701.
[0034]
When the imaging device 701 includes an illumination device, the illumination device irradiates light to the mirror surface portion 1004 of the inner surface mirror 1001, and the irradiated light is directed toward the inner inspection surface 803 of the nozzle 100 by the mirror surface portion 1004. The inner inspection surface 803 is illuminated with the refracted (reflected) and refracted (reflected) light. The shape of the mirror surface portion 1004 of the inner surface mirror 1001 is desirably a shape that matches the shape of the nozzle 100 that is an inspection object. For example, when the nozzle 100 is cylindrical, a conical convex surface is desirable.
[0035]
The upper inspection surface 801, the outer inspection surface 802, and the inner inspection surface 803 shown in FIG. 8 are mapped to image data obtained by the imaging device 701 in which the nozzle 100 provided with the outer mirror 901 and the inner mirror 1001 is photographed from above. The imaging device 701 transmits the captured image data to the inspection surface developing device.
[0036]
In FIG. 7, the inspection surface development device 703 performs image processing on the image data transmitted from the imaging device 701, so that the upper inspection surface 801, the outer inspection surface 802, and the inner inspection surface 803 are reflected in the image data. Judgment and extraction. Next, the region of the upper inspection surface 801 determined and extracted from the image data is coordinate-converted based on the shape reflected in the image data and the shape of the nozzle 100 to create a flat upper inspection surface development image.
[0037]
In addition, the regions of the outer inspection surface 802 and the inner inspection surface 803 determined and extracted from the image data are also coordinate-converted based on the shape reflected in the image data, the shape of the nozzle 100, and the shapes of the mirrors 901 and 1001 to obtain a flat surface. An outer inspection surface development image and an inner inspection surface development image are created. By creating the pre-deployed image, it is possible to unify different inspection resolutions at each inspection location, and it is possible to appropriately evaluate damage dimension measurement and the like. Thereby, the fall of a test | inspection precision can be suppressed.
[0038]
In the evaluation device 704, the developed image created by the inspection surface development device 703 is subjected to image processing to automatically recognize and inspect the damage generated on the surface of the nozzle 100. As an example of image processing for automatically obtaining damage, a binarization process is performed in which a differentiation process is first performed in order to obtain an outline of damage, and then a region where the magnitude of the differential component is equal to or greater than a threshold value is extracted. To do. Since the result extracted by the binarization process is a damage contour line, a closed region embedding process is performed in which a region surrounded by the contour line is a damaged region. A noise removal process for selecting an area of the region extracted by embedding the closed region to a certain threshold value or more is executed, and the region extracted by the previous processing is damaged.
[0039]
The result of automatically inspecting the appearance of the nozzle 100 by the evaluation device 704 is displayed as an overlay on each developed image by changing the color of the damaged area automatically recognized on the display device 6 with information that is easy to understand visually. In addition to the previous display, the pass / fail judgment result, the dimension information of damage, and the like are simultaneously output to the display device 6. The inspection result of the evaluation device 704 is recorded and stored in the inspection result recording device 7 together with inspection process information such as image data of the imaging device 701 and a developed image created by the inspection surface development device.
[0040]
The inspection report creation device 8 automatically creates an inspection report in a predetermined format by referring to information necessary as an inspection result or an inspection report from past inspection results recorded and stored in the inspection result recording device 7. You can also
[0041]
【The invention's effect】
As described above, according to the present invention, the damage generated on the surface of a nozzle or the like used in a power generation facility or the like can be automatically and non-destructively inspected two-dimensionally or three-dimensionally. Independent inspection can be performed efficiently with uniform inspection standards.
[Brief description of the drawings]
FIG. 1 is an overall block diagram showing a first embodiment of a surface nondestructive inspection apparatus according to the present invention.
FIG. 2 is a block diagram showing a first specific example of the distance measuring sensor and the distance measuring device of FIG.
FIG. 3 is a block diagram showing a second specific example of the distance measuring sensor and the distance measuring device of FIG. 1;
4 is a block diagram showing a third specific example of the distance measurement sensor and the distance measurement device in FIG. 1;
FIG. 5 is a block diagram showing a fourth specific example of the distance measurement sensor and the distance measurement device in FIG. 1;
6 is a block diagram showing a specific example of the evaluation apparatus of FIG. 1. FIG.
FIG. 7 is an overall block diagram showing a second embodiment of the surface nondestructive inspection apparatus according to the present invention.
8 is a partial longitudinal sectional view showing the nozzle of FIG. 7 in an enlarged manner.
9 is a schematic partial longitudinal sectional view showing a specific example in the vicinity of the imaging device and nozzle of FIG. 7;
10 is a schematic partial longitudinal sectional view showing a specific example different from FIG. 9 in the vicinity of the imaging device and nozzle of FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Distance measuring sensor, 2 ... Moving apparatus, 3 ... Distance measuring apparatus, 4 ... Movement control apparatus, 5 ... Evaluation apparatus, 6 ... Display apparatus, 7 ... Inspection result recording apparatus, 8 ... Inspection report preparation apparatus, 9 ... Input device, 10 ... Distance signal line, 11 ... Control signal line, 12 ... Video signal line, 25 ... A / D converter, 30 ... Inspection signal line, 100 ... Nozzle, 200 ... Inspection surface, 202a, 202b ... Imaging device , 206 ... parallax calculation processor, 207 ... distance calculation processor, 302 ... imaging device, 304a and 304b ... first reflection mirror, 305 ... second reflection mirror, 306a ... first optical path, 306b ... second optical path, 310 ... image division Processor, 311 ... Parallax calculation processor, 312 ... Distance calculation processor, 402 imaging device, 403 laser light irradiation device, 404 laser oscillator, 405 ... Movable mirror, 409 ... Image Physical processor 410 ... Distance calculation processor 502 ... Imaging device 504 ... Laser oscillator 505 ... Polarized lens 509 ... Image processing processor 510 ... Distance calculation processor 600 ... Surface shape image creation device 601 ... Inspection standard creation device ,..., Determination device, 603... Reference shape recording device, 701... Imaging device, 703... Inspection surface development device, 704.

Claims

In surface nondestructive inspection equipment that inspects the inspection surface nondestructively,
A distance measuring sensor for measuring a distance to the inspection surface based on information obtained by photographing the inspection surface;
A moving device that moves the distance measuring sensor to a position where the inspection surface is imaged and further scans the distance measuring sensor along the inspection surface;
A distance measuring device for obtaining a distance to the inspection surface based on a signal from the distance measuring sensor;
Based on the scanning control information of the moving device and the distance information to the inspection surface obtained by the distance measuring device, a shape image representing the shape of the inspection surface is created, and based on the shape image, the inspection surface An evaluation device for detecting damage;
A surface non-destructive inspection apparatus characterized by comprising:

The surface nondestructive inspection apparatus according to claim 1, wherein the distance measurement sensor includes a plurality of imaging devices that image the inspection surface from a plurality of positions having different viewpoints. apparatus.

The surface nondestructive inspection apparatus according to claim 1, wherein the distance measuring sensor includes an imaging device and an optical device, and the optical device transmits light emitted from the inspection surface to the first and second optical paths. First and second reflecting mirrors that respectively transmit along the optical path, and are configured such that light transmitted along the first and second optical paths is input to different positions of the imaging device. A surface non-destructive inspection device.

4. The surface nondestructive inspection apparatus according to claim 2, wherein the distance measuring device obtains a position where the same area is imaged between images of different viewpoints obtained by imaging the inspection surface by the imaging device, and reaches the inspection surface. A non-destructive surface inspection apparatus characterized by being configured to calculate a distance of

2. The surface nondestructive inspection apparatus according to claim 1, wherein the distance measuring sensor includes a laser beam irradiation device that scans a laser beam as a linear locus on the inspection surface, and a reflected light of the laser beam generated on the inspection surface. And a non-destructive surface inspection apparatus characterized by comprising:

2. The surface nondestructive inspection apparatus according to claim 1, wherein the distance measuring sensor polarizes the beam-shaped laser light by a polarizing lens and irradiates the polarized laser light on the inspection surface in a grid pattern. And a non-destructive inspection apparatus characterized by comprising: an imaging device that captures reflected light of laser light generated on the inspection surface.

The surface nondestructive inspection device according to claim 5, wherein the distance measuring device obtains a captured position of the reflected light generated on the inspection surface based on an image captured by the imaging device, and performs the inspection. A non-destructive surface inspection apparatus characterized by being configured to calculate a distance to a surface.

2. The surface nondestructive inspection apparatus according to claim 1, wherein the evaluation device includes a reference shape recording device that records and holds a reference shape of the inspection surface, and compares the shape image with the reference shape to perform the inspection. A non-destructive surface inspection apparatus characterized by being configured to detect surface damage.

In a non-destructive surface inspection apparatus that non-destructively inspects a cylindrical inspection surface having a side surface,
An imaging device for imaging the inspection surface;
A mirror to reflect and transmit light emitted from the side surface of the inspection surface to the imaging device;
A moving device for moving the imaging device to an inspection position;
An inspection surface development device that performs image processing on the image obtained by the imaging device based on the shape of the mirror and the shape reflected on the mirror to create a planar development image;
An evaluation device for detecting damage on the inspection surface based on a flat development image created by the inspection surface development device;
A surface non-destructive inspection apparatus characterized by comprising:

The surface nondestructive inspection apparatus according to claim 9, wherein the inspection surface is a cylindrical outer surface, and the mirror is annularly arranged along a circumferential direction of the cylindrical outer surface. A surface nondestructive inspection device.

The surface nondestructive inspection apparatus according to claim 9, wherein the inspection surface is an inner surface of a cylindrical object, and the mirror is inserted inside the cylindrical object. Inspection device.

10. The surface nondestructive inspection apparatus according to claim 1 or 9, wherein the inspection result recording apparatus that records and holds the inspection result, the inspection result by the evaluation apparatus, and the past inspection result recorded in the inspection result recording apparatus. A surface non-destructive inspection device characterized by further comprising a display device for displaying.

13. The surface nondestructive inspection apparatus according to claim 12, wherein an inspection standard for determining whether or not the inspection surface is inspected by the evaluation device is created based on a past inspection result recorded in the inspection result recording device. A surface non-destructive inspection device, further comprising a preparation device.

The surface nondestructive inspection apparatus according to claim 1, further comprising an inspection report creation apparatus that creates an inspection report based on an output of the evaluation apparatus.

In the non-destructive surface inspection method that non-destructively inspects the inspection surface,
Moving the distance measuring sensor to a position where the inspection surface is imaged, and further moving the distance measuring sensor along the inspection surface; and
An imaging step of imaging the inspection surface by the distance measuring sensor;
A distance measuring step for obtaining a distance to the inspection surface based on a signal from the distance measuring sensor;
Based on the scanning control information of the moving device and the distance information to the inspection surface obtained in the distance measurement step, a shape image representing the shape of the inspection surface is created and the inspection surface of the inspection surface is generated based on the shape image. An evaluation step to detect damage;
A surface nondestructive inspection method characterized by comprising: