JPH02161107A - Turbine rotor blade - Google Patents
Turbine rotor bladeInfo
- Publication number
- JPH02161107A JPH02161107A JP31387588A JP31387588A JPH02161107A JP H02161107 A JPH02161107 A JP H02161107A JP 31387588 A JP31387588 A JP 31387588A JP 31387588 A JP31387588 A JP 31387588A JP H02161107 A JPH02161107 A JP H02161107A
- Authority
- JP
- Japan
- Prior art keywords
- hardened layer
- rotor blade
- turbine rotor
- external surface
- layer
- 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
- 238000005260 corrosion Methods 0.000 claims abstract description 8
- 230000007797 corrosion Effects 0.000 claims abstract description 7
- 239000000463 material Substances 0.000 claims description 22
- 239000011248 coating agent Substances 0.000 claims description 10
- 238000000576 coating method Methods 0.000 claims description 10
- 230000003628 erosive effect Effects 0.000 claims description 7
- 150000004767 nitrides Chemical class 0.000 claims description 5
- NRTOMJZYCJJWKI-UHFFFAOYSA-N Titanium nitride Chemical compound [Ti]#N NRTOMJZYCJJWKI-UHFFFAOYSA-N 0.000 claims description 2
- UFGZSIPAQKLCGR-UHFFFAOYSA-N chromium carbide Chemical compound [Cr]#C[Cr]C#[Cr] UFGZSIPAQKLCGR-UHFFFAOYSA-N 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 claims description 2
- 229910003470 tongbaite Inorganic materials 0.000 claims description 2
- MTPVUVINMAGMJL-UHFFFAOYSA-N trimethyl(1,1,2,2,2-pentafluoroethyl)silane Chemical compound C[Si](C)(C)C(F)(F)C(F)(F)F MTPVUVINMAGMJL-UHFFFAOYSA-N 0.000 claims description 2
- 230000032683 aging Effects 0.000 claims 1
- 238000007740 vapor deposition Methods 0.000 abstract description 8
- 239000007789 gas Substances 0.000 abstract description 7
- 238000005468 ion implantation Methods 0.000 abstract description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 abstract description 4
- 229910052751 metal Inorganic materials 0.000 abstract description 3
- 239000002184 metal Substances 0.000 abstract description 3
- 239000002245 particle Substances 0.000 abstract description 3
- 238000010884 ion-beam technique Methods 0.000 abstract description 2
- 229910052757 nitrogen Inorganic materials 0.000 abstract description 2
- 230000000630 rising effect Effects 0.000 abstract description 2
- 239000012528 membrane Substances 0.000 abstract 2
- 239000006200 vaporizer Substances 0.000 abstract 1
- 239000010410 layer Substances 0.000 description 21
- 150000002500 ions Chemical class 0.000 description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 10
- 229910001347 Stellite Inorganic materials 0.000 description 8
- AHICWQREWHDHHF-UHFFFAOYSA-N chromium;cobalt;iron;manganese;methane;molybdenum;nickel;silicon;tungsten Chemical compound C.[Si].[Cr].[Mn].[Fe].[Co].[Ni].[Mo].[W] AHICWQREWHDHHF-UHFFFAOYSA-N 0.000 description 8
- 238000000034 method Methods 0.000 description 8
- 229910045601 alloy Inorganic materials 0.000 description 6
- 239000000956 alloy Substances 0.000 description 6
- 238000004544 sputter deposition Methods 0.000 description 6
- 150000001875 compounds Chemical class 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000010941 cobalt Substances 0.000 description 2
- 229910017052 cobalt Inorganic materials 0.000 description 2
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 2
- 238000005536 corrosion prevention Methods 0.000 description 2
- 239000006210 lotion Substances 0.000 description 2
- 150000001247 metal acetylides Chemical class 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 239000002344 surface layer Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 238000003483 aging Methods 0.000 description 1
- 239000011247 coating layer Substances 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000007730 finishing process Methods 0.000 description 1
- 239000007943 implant Substances 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 239000012857 radioactive material Substances 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は蒸気タービンの！！ｌＪ翼に係り、特に、湿り
蒸気流による動翼の浸食を防止するのに好適な構造に関
する。[Detailed Description of the Invention] [Industrial Field of Application] The present invention applies to steam turbines! ! The present invention relates to an IJ blade, and particularly to a structure suitable for preventing rotor blade erosion due to wet steam flow.
第２図に低圧段蒸気タービンの構造を示す。複数のディ
スク２をもつロータ１のディスク２の外周部に、放射状
に複数の動翼３が組み立てられている。その前側には、
蒸気流を整流するノズル翼４をもつダイヤフラム５が設
けられている。特に、水分を含む蒸気流の場合を、第３
図で説明する。Figure 2 shows the structure of the low-pressure steam turbine. A plurality of rotor blades 3 are assembled radially around the outer periphery of the disks 2 of a rotor 1 having a plurality of disks 2. On the front side,
A diaphragm 5 with nozzle vanes 4 for rectifying the steam flow is provided. In particular, the case of steam flow containing moisture is considered in the third
This will be explained with a diagram.
ノズル翼４より整流された蒸気の流速６はタービン回転
数による周速度８との相対関係から、動翼流入蒸気速度
９となる。一方、ノズル翼４より同時に流出する水滴は
蒸気流速６の数分の−であるため、流出水滴速度７とな
る。周速度８との相対関係から、動翼３への流入水滴速
度が１０となる。The flow velocity 6 of the steam rectified by the nozzle blade 4 becomes the rotor blade inflow steam velocity 9 from the relative relationship with the circumferential velocity 8 due to the turbine rotation speed. On the other hand, since the water droplets simultaneously flowing out from the nozzle blades 4 have a steam flow rate of 6, the speed of the water droplets flowing out is 7. From the relative relationship with the circumferential velocity 8, the velocity of water droplets flowing into the rotor blade 3 is 10.
この結果、動翼３の流入側に水滴が衝突し侵食されるこ
とになる。このため、従来は特開昭５９−１８０００３
号、特開昭５９−１８０００４号公報に記載のように、
動翼の先端側蒸気流入部にステライト合金（コバルトを
主成分とする）板を接合して防食片としていた。特に、
原子力用蒸気タービンでは、ステライト合金の主成分で
あるコバルトが、二〇−ジョンにより蒸気流中に流出し
、復水器をへて。As a result, water droplets collide with the inlet side of the rotor blade 3, causing erosion. For this reason, conventionally JP-A-59-180003
As described in JP-A-59-180004,
A stellite alloy (mainly composed of cobalt) plate was bonded to the steam inlet on the tip side of the rotor blade to serve as a corrosion protection piece. especially,
In nuclear steam turbines, cobalt, the main component of the stellite alloy, flows out into the steam stream through the 20-john and passes through the condenser.
原子炉へ流入し、放射性物質となり、定検等の分解時に
作業性を低下させていた。そこで、原子力タービンでは
ステライト合金にかわる方法として。It flowed into the reactor and became radioactive material, reducing work efficiency during disassembly during periodic inspections. Therefore, as an alternative to stellite alloys for nuclear power turbines.
動翼のステライト合金を取り付ける部分を高温に加熱し
、動翼自体の侵食部分を硬化させるフレームハード法が
採用されているが、その効果はステライト合金に比べ、
約５０％の耐エロージヨン性しかないため不充分である
。従って、従来のステライト合金に代る防食片、あるい
は、フレームハード法よりも、優れた浸食防止技術が必
要である。The frame hardening method is used to heat the part of the rotor blade where the Stellite alloy is attached to a high temperature and harden the eroded part of the rotor blade itself, but its effectiveness is lower than that of Stellite alloy.
The erosion resistance is only about 50%, which is insufficient. Therefore, there is a need for corrosion prevention techniques that are superior to the conventional corrosion prevention plates or frame hard methods that replace conventional stellite alloys.
本発明の目的は、動翼の蒸気流入側の表面にフレームハ
ード等の硬化層を形成した後に蒸着とイオン注入により
硬化層の表面の硬質被膜を形成するか、又は、時効硬化
性をもつβ型チタン合金に時効硬化処理後、蒸着とイオ
ン注入により表面に硬質被膜を形成することにより達成
することができる。The purpose of the present invention is to form a hardened layer such as frame hard on the surface of the steam inflow side of the rotor blade, and then form a hard coating on the surface of the hardened layer by vapor deposition and ion implantation, or to This can be achieved by forming a hard coating on the surface of the type titanium alloy by vapor deposition and ion implantation after age hardening.
本発明のタービン動翼は、その先端部のみ、動翼材を硬
化した基材表面」―に一種以上の元素からなる蒸着膜を
形成し、その蒸着膜にイオン注入を行って作られる。こ
れによＶ蒸着膜の成分と注入されたイオンとが反応して
、硬質の化合物を生成して、蒸着膜の表面層に化合物層
となって、水分流に対する耐浸食性をもつと共に、蒸着
膜と基材との境界部に、化合物の成分と基材の成分とが
強制的に混合された混合層が形成され、膜厚方向に緩や
かに成分濃度が変化するため、蒸着膜と基材とは強力に
接合された状態となり、かつ、化合物を含有するので高
い硬度をもつことになる。The turbine rotor blade of the present invention is produced by forming a vapor deposited film of one or more elements on the surface of a base material made of hardened rotor blade material only at the tip thereof, and then implanting ions into the vapor deposited film. As a result, the components of the V-deposited film and the implanted ions react to form a hard compound, which forms a compound layer on the surface layer of the V-deposited film, which has corrosion resistance against water flow and At the boundary between the film and the substrate, a mixed layer is formed in which the components of the compound and the components of the substrate are forcibly mixed, and the concentration of the components changes gradually in the film thickness direction. It is in a strongly bonded state and has high hardness because it contains a compound.
これらの化合物層と混合層とで構成される硬質被膜を設
けることにより、更に、高い耐浸食性をタービン動翼に
与えることができる。By providing a hard coating composed of these compound layers and a mixed layer, even higher corrosion resistance can be imparted to the turbine rotor blade.
本発明の実施例を第１図により説明する。動翼３材自体
を熱処理、又は、時効硬化性のある防食片を接合し、時
効硬化処理し、硬化層１１を形成する。その後、硬化層
１１の外表面に蒸着法とスパッタリング法により、硬化
層１１との成分の混合層２０が形成され、さらには、窒
化物、又は、炭化物だけの硬質被膜１２が、その外表面
を形成する。以下、蒸着法、スパッタリング法について
説明する。An embodiment of the present invention will be described with reference to FIG. The rotor blade 3 material itself is heat-treated, or an age-hardenable anti-corrosion piece is joined and age-hardened to form the hardened layer 11. Thereafter, a mixed layer 20 of the components of the hardened layer 11 is formed on the outer surface of the hardened layer 11 by vapor deposition and sputtering, and furthermore, a hard coating 12 of only nitride or carbide is formed on the outer surface of the hardened layer 11. Form. The vapor deposition method and sputtering method will be explained below.
真空ポンプ１９により真空状態の中で、電子ビーム加熱
方式の金属蒸発器１４からたちのぼる金属蒸気１３を、
硬化層１１の表面に蒸着させる。The metal vapor 13 rising from the electron beam heating type metal evaporator 14 is heated in a vacuum state by the vacuum pump 19.
It is vapor-deposited on the surface of the hardened layer 11.
また、別の方向より窒素等のガス１８をガス制御器１７
により流量を調整し、イオン源１−６でガス１８をイオ
ン化し、イオンビーム１５としてイオンを加速し、硬化
層１１の内部へ注入され、同時に硬化層１１の中の粒子
がはじき出され、イオンと置換されることをスパッタリ
ング（又はスパッタリング法）と称する。硬化層１１の
表面近傍は蒸着法、あるいは、スパッタリング法で形成
される粒子と硬化層１１の成分の混合された状態の混合
層２０が形成される。硬化層１１、及び、蒸着膜に注入
されたガスイオンは、その運動エネルギが熱エネルギに
変換され高熱を発する。In addition, a gas 18 such as nitrogen is supplied to the gas controller 17 from another direction.
The gas 18 is ionized by the ion source 1-6, the ions are accelerated as an ion beam 15, and are injected into the hardened layer 11. At the same time, the particles in the hardened layer 11 are expelled, and the ions are This substitution is called sputtering (or sputtering method). Near the surface of the hardened layer 11, a mixed layer 20 is formed in which particles formed by a vapor deposition method or a sputtering method and components of the hardened layer 11 are mixed. The kinetic energy of the gas ions injected into the hardened layer 11 and the deposited film is converted into thermal energy and generates high heat.
基材、及び、蒸着膜の成分は注入されたガスイオンと反
応して、窒化物、炭化物等が形成される。The base material and the components of the deposited film react with the injected gas ions to form nitrides, carbides, and the like.
しかし、高温となる部分は、きわめて表層のみであるた
め、基材の温度を低く保つことができる。However, since only the surface layer becomes high temperature, the temperature of the base material can be kept low.
また、基材を冷却することも可能である。このため、材
質の変化や変形がない。また、被膜の形成の手法として
、蒸着、あるいは、スパッタリングにより蒸着膜を形成
しながらイオンの注入をするのが望ましい。このように
して形成された窒化物、又は、炭化物の各層は、非常に
緻密であり、また、硬質層であるため、水分流に対する
耐浸食性が大巾に改善される。本発明による方法は動翼
の材質の変化がないため、基材の性質を維持することが
できる。また温度も低く保たれるため、変形が、はとん
どない。動翼材の表面へ形成する窒化物は窒化チタン、
炭化物は炭化チタン、炭化タングステン、炭化クロム等
の硬質のものが非常によい。It is also possible to cool the base material. Therefore, there is no change or deformation of the material. Further, as a method for forming the film, it is desirable to implant ions while forming a deposited film by vapor deposition or sputtering. Each layer of nitride or carbide formed in this way is very dense and hard, so that the erosion resistance against water flow is greatly improved. Since the method according to the present invention does not change the material of the rotor blade, the properties of the base material can be maintained. Also, since the temperature is kept low, deformation is unlikely. The nitride that forms on the surface of the moving blade material is titanium nitride,
Hard carbides such as titanium carbide, tungsten carbide, and chromium carbide are very good.
本発明によるタービン動翼は耐浸食性に優れた硬質被膜
が形成され、その硬質被膜は硬質被膜の成分と基材の成
分から成る混合層の存在によって。In the turbine rotor blade according to the present invention, a hard coating with excellent corrosion resistance is formed, and the hard coating is due to the presence of a mixed layer consisting of components of the hard coating and components of the base material.
密着性が非常に優れ、剥離の心配がない。また、温度が
低いため、変形がほとんどないことから、最終仕上げ加
工後に硬質被膜層を形成することができる。It has excellent adhesion and there is no need to worry about it peeling off. Furthermore, since the temperature is low, there is almost no deformation, so a hard coating layer can be formed after the final finishing process.
第４図は、直径９００ｍｍ、回転数１２５０Ｏｒ、ｐ、
ｍ。Figure 4 shows a diameter of 900 mm, rotation speed of 1250 Or, p,
m.
排気真空６７０ｗｎＨｇと動翼部の回転時の条件を模擬
し、ノズル翼より流出する水流を考慮した噴霧スプレー
水方式の試験装置を使用し、ステライト、１２Ｃｒ鋼に
熱処理を行ない、硬化層を設けたフレームハード材、蒸
着、および、イオン注入法による成膜条件は、加速電圧
：２０ｋＶ、電流０．２０Ａ、イオン注入量：１５Ｘ１
０”個イオン／ ａｎ ”によりフレームハード材およ
びＴｉ−１５Ｍｏ−５Ｚｒ−３ＡＱ材の効果を確認した
。Stellite and 12Cr steel were heat-treated to form a hardened layer using a spray water test device that simulates the exhaust vacuum of 670wnHg and the rotation of the rotor blades, and takes into account the water flow flowing out from the nozzle blades. The film forming conditions for the frame hard material, vapor deposition, and ion implantation method are acceleration voltage: 20 kV, current 0.20 A, ion implantation amount: 15×1
The effects of the frame hard material and the Ti-15Mo-5Zr-3AQ material were confirmed using 0"ions/an".
図中の横軸は時間、縦軸は二〇−ジョンレイトｍ３／ｎ
ｎ”を示す。図からフレームハード材に蒸着およびイオ
ン注入処理材、Ｔｉ−１５Ｍｏ−５２ｒ−３ＡＩ２に蒸
着および注入処理材がステライト材に比ベニローション
レイト（ｍ’／ ａｉ３）が小さく耐エロージヨン性に
優れていることが判る。第１表は、各材料を、試験温度
６０℃の純水中で、周波数２５ＫＨｚ、振幅３５μｍ、
試験時間１５時間の条件でキャビテーション試験により
効果を確認した結果である。いずれも、本発明材は耐エ
ロージヨン性に優れていることがわかる。The horizontal axis in the figure is time, and the vertical axis is 20-john rate m3/n
The figure shows that the vapor deposited and ion implanted material on the frame hard material and the vapor deposited and implanted material on Ti-15Mo-52r-3AI2 have a smaller vene lotion rate (m'/ai3) than the Stellite material and have better erosion resistance. Table 1 shows that each material was tested in pure water at a test temperature of 60°C at a frequency of 25 KHz, an amplitude of 35 μm, and
This is the result of confirming the effect through a cavitation test under the conditions of a test time of 15 hours. In both cases, it can be seen that the materials of the present invention have excellent erosion resistance.
第 １ 表
〔発明の効果〕
本発明によれば、耐二ローション性に優れたタービン動
翼を提供することができる。Table 1 [Effects of the Invention] According to the present invention, it is possible to provide a turbine rotor blade having excellent second lotion resistance.
第１図は本発明の一実施例の説明図、第２図は蒸気ター
ビンの低圧段断面図、第３図は第２図の断面■−■部の
蒸気および水滴流の説明図、第４図は回転二〇−ジョン
試験結果を示す図である。
１・・・ロータ、２・・・ディスク、３・・・動翼、４
・・・ノズル翼、５・・・ダイヤフラム。Fig. 1 is an explanatory diagram of an embodiment of the present invention, Fig. 2 is a cross-sectional view of the low pressure stage of a steam turbine, Fig. 3 is an explanatory diagram of steam and water droplet flow in the section ■-■ of Fig. 2, and Fig. 4 is an explanatory diagram of an embodiment of the present invention. The figure shows the results of a rotating 20-john test. 1... Rotor, 2... Disc, 3... Moving blade, 4
... Nozzle blade, 5... Diaphragm.
Claims (1)
れた複数の動翼の先端側蒸気流入部に設ける耐エロージ
ヨン防止用防食片を別体より成形して溶接し、時効処理
により硬化材とするか、又は、前記動翼の前記先端側蒸
気流入部の表面のみを加熱処理により硬化した後に、一
種以上の元素により、硬化部の表面に硬質被膜を形成し
たことを特徴とするタービン動翼。 ２、前記硬質被膜が窒化チタンからなる窒化物から形成
されていることを特徴とする特許請求の範囲第１項に記
載のタービン動翼。 ３、前記硬質被膜が炭化チタン炭化クロム等の炭化物か
ら成ることを特徴とする特許請求の範囲第１項に記載の
タービン動翼。[Scope of Claims] 1. A corrosion-resistant piece for preventing erosion is separately formed and welded to be provided at the tip-side steam inflow portion of a plurality of rotor blades implanted along the outer periphery of the wheel portion of the turbine rotor, Either the material is made into a hardened material by aging treatment, or after the surface of the tip side steam inlet portion of the rotor blade is hardened by heat treatment, a hard coating is formed on the surface of the hardened portion with one or more elements. Characteristic turbine rotor blades. 2. The turbine rotor blade according to claim 1, wherein the hard coating is formed from a nitride made of titanium nitride. 3. The turbine rotor blade according to claim 1, wherein the hard coating is made of a carbide such as titanium carbide or chromium carbide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP31387588A JPH02161107A (en) | 1988-12-14 | 1988-12-14 | Turbine rotor blade |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP31387588A JPH02161107A (en) | 1988-12-14 | 1988-12-14 | Turbine rotor blade |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02161107A true JPH02161107A (en) | 1990-06-21 |
Family
ID=18046560
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP31387588A Pending JPH02161107A (en) | 1988-12-14 | 1988-12-14 | Turbine rotor blade |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02161107A (en) |
-
1988
- 1988-12-14 JP JP31387588A patent/JPH02161107A/en active Pending
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