JPH0423209B2 - - Google Patents
Info
- Publication number
- JPH0423209B2 JPH0423209B2 JP55160275A JP16027580A JPH0423209B2 JP H0423209 B2 JPH0423209 B2 JP H0423209B2 JP 55160275 A JP55160275 A JP 55160275A JP 16027580 A JP16027580 A JP 16027580A JP H0423209 B2 JPH0423209 B2 JP H0423209B2
- Authority
- JP
- Japan
- Prior art keywords
- hardness
- rotor
- center hole
- impact body
- detection
- 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
- 238000001514 detection method Methods 0.000 claims description 27
- 230000002093 peripheral effect Effects 0.000 claims description 15
- 230000006866 deterioration Effects 0.000 description 6
- 238000005259 measurement Methods 0.000 description 6
- 230000006378 damage Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000007542 hardness measurement Methods 0.000 description 2
- 230000003213 activating effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/40—Investigating hardness or rebound hardness
- G01N3/52—Investigating hardness or rebound hardness by measuring extent of rebound of a striking body
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Description
【発明の詳細な説明】
〔発明の目的〕
（産業上の利用分野）
本発明はたとえばタービンや発電機のロータの
中心孔周壁の硬度を測定するためのロータの硬度
測定装置に関する。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a rotor hardness measuring device for measuring the hardness of a peripheral wall of a center hole of a rotor of a turbine or a generator, for example.
（従来の技術）
たとえばタービンロータには軸方向に延びる中
心孔が穿設されていて、ロータ製造時に中心孔か
らの探傷検査を行なつて製品の品質をチエツクし
ているが、圧力約250Kg／cm2ata、温度約550℃の
超高温：超高圧域で使用されるロータについて
は、長期間の使用に伴つて蓄積されるクレープや
熱疲労損傷により材質の劣化が進行したり割れが
発生することがあるので、タービン運転時にも定
期的にロータ外表面や中心孔周面について探傷検
査を行なうとともに材質劣化を判定するための硬
度測定をロータ表面について行なつている。(Prior art) For example, a turbine rotor has a center hole that extends in the axial direction, and when the rotor is manufactured, flaw detection from the center hole is performed to check the quality of the product, but the pressure is about 250 kg/ cm 2 ata, ultra-high temperature of approximately 550℃: For rotors used in ultra-high pressure areas, material deterioration progresses and cracks occur due to crepe and thermal fatigue damage that accumulate over long periods of use. Therefore, even during turbine operation, flaw detection is periodically performed on the outer surface of the rotor and the circumferential surface of the center hole, and hardness measurements are also performed on the rotor surface to determine material deterioration.
（発明が解決しようとする問題点）
一方タービンロータにおいて最も作用応力が大
きく、材質劣化も大きい部位は中心孔の周壁であ
る。(Problems to be Solved by the Invention) On the other hand, in the turbine rotor, the area where the applied stress is the largest and the material deterioration is the greatest is the peripheral wall of the center hole.
即ち中心孔の周壁においては稼働中の高速回転
により大きな遠心応力が作用し、クリープによる
材質劣化の進行が著しい。したがつてロータの材
質劣化を判定し、破壊に対する安全性を確認する
ために、中心孔の周壁部分の硬度を測定すること
が要求されることになる。 That is, large centrifugal stress acts on the peripheral wall of the center hole due to high-speed rotation during operation, and material deterioration due to creep progresses significantly. Therefore, it is required to measure the hardness of the peripheral wall of the center hole in order to determine the deterioration of the material of the rotor and confirm its safety against destruction.
しかしタービンロータの中心孔の長さは５ｍ以
上もあり、しかも孔径はロータの外径約700mmに
対し70〜100mm前後）と小径であるから、広く使
用されているシヨア硬度計のような可搬型で小形
の硬度計でも高さが180mm程度な為中心孔への挿
入ができず、タービンロータの中心孔周壁全域に
亘つて硬度を測定することが現在までできなかつ
た。シヨア硬度計は、内蔵されたハンマーを所定
の高さに保持した後自由落下させ、被計測物に衝
突してはね返つた高さを機械的なメータで読み取
る構造を有している。したがつて十分な打撃エネ
ルギーを得る為にはある程度の初期高さが必要で
あり、原理的に小型化が難しかつた。 However, the length of the center hole of the turbine rotor is more than 5 m, and the hole diameter is small (around 70 to 100 mm compared to the rotor's outer diameter of about 700 mm), so it is difficult to use a portable type like the widely used Shore hardness tester. Even a small hardness meter has a height of about 180 mm, so it cannot be inserted into the center hole, and until now it has not been possible to measure the hardness of the entire circumferential wall of the center hole of the turbine rotor. The Shore hardness tester has a structure in which a built-in hammer is held at a predetermined height and then allowed to fall freely, and the height at which it bounces back when it collides with the object to be measured is read by a mechanical meter. Therefore, in order to obtain sufficient impact energy, a certain initial height is required, and it is theoretically difficult to miniaturize the ball.
本発明は上記した点に鑑みてなされたもので、
ロータの中心孔に可動に配置される硬度計作動装
置に、バネ等で初期速度を与えたインパクトボデ
イの衝突・反撥速度を電気的に計測し得る形式の
硬度検出装置を設け、硬度計作動装置を遠隔操作
するとともに、硬度検出装置の信号を表示装置に
導き、中心孔周壁の硬度をロータの全長に亘つて
測定し得るようにしたロータの硬度測定装置を提
供することを目的とする。 The present invention has been made in view of the above points, and
The hardness meter actuating device movably disposed in the center hole of the rotor is equipped with a hardness detecting device capable of electrically measuring the collision/repulsion speed of the impact body given an initial velocity by a spring or the like. An object of the present invention is to provide a rotor hardness measuring device that can remotely control the hardness of the rotor, guide the signal from the hardness detecting device to a display device, and measure the hardness of the peripheral wall of the center hole over the entire length of the rotor.
（問題点を解決するための手段）
本発明は、ロータの中心孔に可動に配置される
台車付の硬度計作動装置と、この硬度計作動装置
の前端部分に回動自在に枢着された検出部分に収
められ、ロータの忠心孔周壁の上下左右に対して
衝突・反撥を繰り返すインパクトボデイと、この
インパクトボデイの衝突・反撥を繰り返す動作速
度を電気的に検出する手段とを有する硬度検出装
置と、この硬度検出装置の信号を受け硬度に換算
して表示する表示装置と、上記硬度計作動装置を
遠隔操作するための操作装置とを有するロータの
硬度測定装置である。
(Means for Solving the Problems) The present invention includes a hardness meter actuating device with a trolley movably disposed in the center hole of a rotor, and a hardness meter actuating device with a cart attached to the hardness meter actuating device movably disposed in the center hole of a rotor, and a hardness meter actuating device rotatably pivoted to the front end portion of the hardness meter actuating device. A hardness detection device that is housed in a detection part and has an impact body that repeatedly collides with and repulses against the upper, lower, left, and right sides of a circumferential wall of a loyalty hole of a rotor, and a means for electrically detecting the operating speed of this impact body that repeatedly collides and repulses. This rotor hardness measuring device includes: a display device that receives a signal from the hardness detecting device, converts it into hardness and displays it, and an operating device for remotely controlling the hardness meter operating device.
（作用）
上記の構成において、硬度検出装置を搭載した
硬度計作動装置は、ロータ中心孔内径よりも小径
の柱状に形成されており、外部から操作装置によ
りロツドを介して測定位置まで中心孔内に挿入さ
れる。測定時には操作装置からの遠隔操作により
硬度検出装置が作動するようになつており、測定
された硬度は中心孔外部に設置された表示装置へ
導かれて表示される。(Function) In the above configuration, the hardness meter actuating device equipped with the hardness detection device is formed in the shape of a column with a smaller diameter than the inner diameter of the rotor center hole, and is moved into the center hole from the outside to the measurement position via the rod by the operating device. inserted into. During measurement, the hardness detection device is activated by remote control from the operating device, and the measured hardness is led to and displayed on a display device installed outside the center hole.
かかる構成によれば、中心孔周壁の硬度をロー
タの全長に亘つて必要な部位について測定するこ
とができる。 According to this configuration, the hardness of the peripheral wall of the center hole can be measured at necessary locations over the entire length of the rotor.
（実施例） 以下本発明の一実施例を図面につき説明する。(Example) An embodiment of the present invention will be described below with reference to the drawings.
第１図において符号１は、硬度計作動装置であ
つて、その硬度計作動装置１は、タービンロータ
２の中心孔３に可動に配置されている。すなわち
上記硬度計作動装置１は車輪４ａ，４ｂを有する
とともに、作動ケーブルを内包した連結ロツド５
を介してロータ外部に設置した遠隔操作装置６に
連結されていて、中心孔３の周壁３ａに沿つて周
方向および軸線方向に動き得るようになつてい
る。また上記硬度計作動装置１の前端部には、硬
度検出装置７が固設されている。 In FIG. 1, reference numeral 1 denotes a hardness meter operating device, and the hardness meter operating device 1 is movably disposed in a center hole 3 of a turbine rotor 2. As shown in FIG. That is, the hardness meter operating device 1 has wheels 4a, 4b, and a connecting rod 5 containing an operating cable.
The rotor is connected to a remote control device 6 installed outside the rotor through the rotor, and is movable in the circumferential direction and the axial direction along the peripheral wall 3a of the center hole 3. Further, a hardness detection device 7 is fixedly installed at the front end of the hardness meter actuating device 1.
上記硬度検出装置７は、第２図に示すように、
本体部分８と、その本体部分８に回動自在に枢着
された検出部分９とを有し、その検出部分９はイ
ンパクトボデイ１０の衝突・反搬速度を電気的に
計測するようになつている。第３図はこの検出部
分９の詳細を示すもので、先端部にテストチツプ
１１を備え磁化されたインパクトボデイ１０は一
端が開口した円筒状のガイド管１２内に可動に収
納され、さらにこのガイド管１２内にはインパク
トボデイ１０を付勢するスプリング１３およびス
プリング１３によつて付勢した状態でインパクト
ボデイ１０を係止させるチヤツク１４、さらにこ
のチヤツク１４とインパクチボデイ１０の係合を
解除するリリースボタン１５が配設され、他方ガ
イド管１２の外周部開口端近傍には、インパクト
ボデイ１０の動作速度を検出する検出手段として
のコイル１６が巻回されている。このコイル１６
は高周波ケーブル１７を介してロータ外部に設置
された硬度換算手段を有する硬度表示装置１８に
結線されており、コイル１６で検出された硬度の
電気変換信号を硬度表示装置１８に導き、デイジ
タル表示で硬度測定値を表示し得るようになつて
いる。 As shown in FIG. 2, the hardness detection device 7 includes:
It has a main body part 8 and a detection part 9 rotatably attached to the main body part 8, and the detection part 9 is adapted to electrically measure the collision and reversal velocity of the impact body 10. There is. FIG. 3 shows details of this detection part 9. A magnetized impact body 10 with a test chip 11 at its tip is movably housed in a cylindrical guide tube 12 with one end open. 12 includes a spring 13 that biases the impact body 10, a chuck 14 that locks the impact body 10 in a state biased by the spring 13, and a release that releases the engagement between the chuck 14 and the impact body 10. A button 15 is provided, and a coil 16 serving as a detection means for detecting the operating speed of the impact body 10 is wound around the outer peripheral open end of the guide tube 12 . This coil 16
is connected via a high frequency cable 17 to a hardness display device 18 having a hardness conversion means installed outside the rotor, and guides the electrical conversion signal of the hardness detected by the coil 16 to the hardness display device 18 and displays it digitally. Hardness measurements can be displayed.
次に作用を説明する。 Next, the action will be explained.
まず硬度計作動装置１を、測定しようとするタ
ービンロータ２の中心孔３に挿入し、遠隔操作装
置６を作動させることで硬度計作動装置１をロツ
ド５を介して軸線方向に動かし硬度検出装置７の
検出部分９を中心孔周壁３ａの測定すべき位置に
対応するように位置させる。この状態で硬度検出
装置７のリセツトを行なう。すなわち、図示しな
い空気圧による駆動装置によつて、まず検出部分
９をガイド管１２開口部が硬度計作動装置１の側
に向いて軸線方向と平行になるよう回転させて保
持し、この状態で図示しない駆動装置によつてイ
ンパクトボデイ１０をガイド管１２の奥へスプリ
ング１３に抗して押込み、チヤツク１４にインパ
クトボデイ１０を係合させる。しかしてインパク
トボデイ１０がチヤツク１４に係止させたら検出
部分９をガイド管１２が中心孔３の周壁３ａに垂
直となるよう回転して、さらに第３図に示すよう
にガイド管１２の開口端を中心孔３の周壁３ａに
当接させる。 First, the hardness meter actuating device 1 is inserted into the center hole 3 of the turbine rotor 2 to be measured, and by activating the remote control device 6, the hardness meter actuating device 1 is moved in the axial direction via the rod 5. The detection portion 9 of No. 7 is positioned so as to correspond to the position to be measured on the peripheral wall 3a of the center hole. In this state, the hardness detection device 7 is reset. That is, by a pneumatic drive device (not shown), first, the detection part 9 is rotated and held so that the opening of the guide tube 12 faces the hardness meter actuating device 1 and is parallel to the axial direction, and in this state, the detection part 9 is held as shown in the figure. The impact body 10 is pushed into the inner part of the guide tube 12 against the spring 13 by a driving device that does not move, and the impact body 10 is engaged with the chuck 14. When the impact body 10 is locked to the chuck 14, the detection part 9 is rotated so that the guide tube 12 is perpendicular to the peripheral wall 3a of the center hole 3, and then the open end of the guide tube 12 is rotated as shown in FIG. is brought into contact with the peripheral wall 3a of the center hole 3.
これでリセツトは完了し、遠隔操作装置６から
図示しない空気圧による駆動装置を介して検出部
分９のリセツトボタン１５を押すと、インパクト
ボデイ１０を係止しているチヤツク１４が解除さ
れ、インパクトボデイ１０はスプリング１３の弾
性力によつて中心孔周壁３ａに速度υoで衝突し、
この衝突によつて今度は逆向きに速度υ1で反撥す
る。インパクトボデイ１０はスプリング１３の弾
性力によつて初期速度を与えられる為、ガイド管
１２が短くとも十分な衝突速度υ0を得ることがで
きる。なお、中心孔周壁３ａに衝突するのはイン
パクトボデイ１０に固着された硬質のテストチツ
プ１１部分である。 The reset is now complete, and when the reset button 15 of the detection part 9 is pressed from the remote control device 6 via a pneumatic drive device (not shown), the chuck 14 locking the impact body 10 is released, and the impact body 10 is released. collides with the center hole peripheral wall 3a at a speed υ o due to the elastic force of the spring 13,
As a result of this collision, it is now repelled in the opposite direction with a speed of υ 1 . Since the impact body 10 is given an initial velocity by the elastic force of the spring 13, a sufficient impact velocity υ 0 can be obtained even if the guide tube 12 is short. It is the portion of the hard test chip 11 fixed to the impact body 10 that collides with the peripheral wall 3a of the center hole.
インパクトボデイ１０は磁化されているから、
ガイド管１２のコイル１６が巻回されている部分
を通過すると、コイル１６に電流が流れ、このと
きコイルに生ずる電圧とインパクトボデイ通過速
度との間には第４図に示すように正比例と関係が
ある。他方、インパクトボデイ通過速度の比υ1／
υo（＝反撥速度／打撃速度）は第５図に示すよう
に硬さと相関関係があり、これらの関係から、コ
イル１６に生ずる電圧を測定することにより、中
心孔周壁３ａの硬さ値を求めることができる。 Because Impact Body 10 is magnetized,
When passing through the part of the guide tube 12 where the coil 16 is wound, a current flows through the coil 16, and there is a direct proportional relationship between the voltage generated in the coil and the impact body passing speed as shown in FIG. There is. On the other hand, the ratio of impact body passing speed υ 1 /
υ o (=repulsion speed/impact speed) has a correlation with hardness as shown in FIG. You can ask for it.
コイル１６に生じた電圧は高周波ケーブル１７
を介して硬度表示装置１８で測定され、内蔵され
た硬さ値と電圧比υ1／υ0の関係に基づいて、硬さ
値に換算してデイジタル表示される。 The voltage generated in the coil 16 is transferred to the high frequency cable 17
The hardness is measured by the hardness display device 18, and is converted into a hardness value and digitally displayed based on the relationship between the built-in hardness value and the voltage ratio υ 1 /υ 0 .
測定が終わり、続いて他の測定を行う場合には
再び硬度検出装置７はリセツトされるが、リセツ
トから測定までに要するガイド管の回転、リリー
スボタンの押込み等の一連の動作は、全て外部か
ら供給されるエアー（圧縮空気）を用いて行わ
れ、このエアーは遠隔操作装置６で制御される。
なお、圧縮空気以外にも油圧或いは電気による動
力を用いることももちろん可能で、このような駆
動手段は公知の種々の構成とすることができるの
は言うまでもない。 When a measurement is completed and another measurement is to be performed, the hardness detection device 7 is reset again, but the series of operations required from reset to measurement, such as rotating the guide tube and pressing the release button, are all performed externally. This is performed using supplied air (compressed air), and this air is controlled by a remote control device 6.
Note that it is of course possible to use hydraulic or electric power in addition to compressed air, and it goes without saying that such drive means can have various known configurations.
以上述べたような本発明によれば、ロータの中
心孔に硬度検出装置を設けた硬度計作動装置が挿
入され、その硬度検出装置が遠隔操作装置により
中心孔の軸線方向および周方向に動かされるよう
になつているので、従来不可能であつたロータ中
心孔全周の周壁の硬度を測定し得、したがつてロ
ータの材質劣化の測定や破壊に対する安全性を確
認でき、ロータの品質管理を効率よく行ない得る
という効果を奏する。また、本装置はロータの中
心孔に限らず、配管その他の小径の中空円筒状部
材の内面硬度測定に適用可能である。
According to the present invention as described above, a hardness meter operating device provided with a hardness detection device is inserted into the center hole of the rotor, and the hardness detection device is moved in the axial direction and circumferential direction of the center hole by a remote control device. As a result, it is possible to measure the hardness of the peripheral wall around the entire circumference of the rotor center hole, which was previously impossible, and it is therefore possible to measure the deterioration of the rotor's material and confirm its safety against destruction, making it possible to efficiently control the quality of the rotor. It has the effect of being able to do something. Furthermore, this device is applicable not only to the measurement of the inner surface hardness of the center hole of the rotor but also to pipes and other small-diameter hollow cylindrical members.
第１図は本発明によるロータの硬度測定装置の
使用状態を示す説明図、第２図は同硬度測定装置
の要部拡大図、第３図は硬度検出部分の断面図、
第４図はインパクトボデイの速度と電圧の関係を
示す線図、第５図は速度比と硬さの関係を示す線
図である。
１……硬度計作動装置、２……タービンロー
タ、３……中心孔、５……連結ロツド、６……遠
隔操作装置、７……硬度検出装置、９……検出部
分、１０……インパクトボデイ、１１……テスト
チツプ、１２……ガイド管、１３……スプリン
グ、１４……チヤツク、１５……リリースボタ
ン、１６……コイル、１７……高周波ケーブル、
１８……硬度表示装置。
FIG. 1 is an explanatory diagram showing the usage state of the rotor hardness measuring device according to the present invention, FIG. 2 is an enlarged view of the main part of the same hardness measuring device, and FIG. 3 is a sectional view of the hardness detection part.
FIG. 4 is a diagram showing the relationship between impact body speed and voltage, and FIG. 5 is a diagram showing the relationship between speed ratio and hardness. DESCRIPTION OF SYMBOLS 1... Hardness meter actuation device, 2... Turbine rotor, 3... Center hole, 5... Connection rod, 6... Remote control device, 7... Hardness detection device, 9... Detection part, 10... Impact Body, 11...Test chip, 12...Guide tube, 13...Spring, 14...Chuck, 15...Release button, 16...Coil, 17...High frequency cable,
18...Hardness display device.
Claims (1)
硬度計作動装置と、この硬度計作動装置の前端部
分に回動自在に枢着された検出部分に収められ、
ロータの中心孔周壁の上下左右に対して衝突・反
撥を繰り返すインパクトボデイと、このインパク
トボデイの衝突・反撥を繰り返す動作速度を電気
的に検出する手段とを有する硬度検出装置と、こ
の硬度検出装置の信号を受け硬度に換算して表示
する表示装置と、上記硬度計作動装置を遠隔操作
するための操作装置とを有するロータの硬度測定
装置。1 A hardness meter actuating device with a trolley movably disposed in the center hole of the rotor, and a detection portion rotatably mounted on the front end of the hardness meter actuating device,
A hardness detection device comprising an impact body that repeatedly collides with and repulses against the upper, lower, left and right sides of a peripheral wall of a center hole of a rotor, and a means for electrically detecting the operating speed of this impact body that repeatedly collides and repulses, and this hardness detection device. A rotor hardness measuring device comprising: a display device that receives a signal, converts it into hardness, and displays the hardness; and an operating device for remotely controlling the hardness meter operating device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16027580A JPS5784336A (en) | 1980-11-14 | 1980-11-14 | Hardness measuring apparatus for rotor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16027580A JPS5784336A (en) | 1980-11-14 | 1980-11-14 | Hardness measuring apparatus for rotor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5784336A JPS5784336A (en) | 1982-05-26 |
| JPH0423209B2 true JPH0423209B2 (en) | 1992-04-21 |
Family
ID=15711468
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16027580A Granted JPS5784336A (en) | 1980-11-14 | 1980-11-14 | Hardness measuring apparatus for rotor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5784336A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5264987A (en) * | 1975-11-25 | 1977-05-28 | Nippon Steel Corp | Apparatus for and method of detecting unevenness heat treatment in hea t treated steel pipe |
-
1980
- 1980-11-14 JP JP16027580A patent/JPS5784336A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5264987A (en) * | 1975-11-25 | 1977-05-28 | Nippon Steel Corp | Apparatus for and method of detecting unevenness heat treatment in hea t treated steel pipe |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5784336A (en) | 1982-05-26 |
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