JPS62182290A - Method for preventing hydrogen embrittlement of member - Google Patents
Method for preventing hydrogen embrittlement of memberInfo
- Publication number
- JPS62182290A JPS62182290A JP2482686A JP2482686A JPS62182290A JP S62182290 A JPS62182290 A JP S62182290A JP 2482686 A JP2482686 A JP 2482686A JP 2482686 A JP2482686 A JP 2482686A JP S62182290 A JPS62182290 A JP S62182290A
- Authority
- JP
- Japan
- Prior art keywords
- hydrogen peroxide
- hydrogen
- hydrogen embrittlement
- water
- embrittlement
- 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
- 239000001257 hydrogen Substances 0.000 title claims abstract description 64
- 229910052739 hydrogen Inorganic materials 0.000 title claims abstract description 64
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 title claims abstract description 62
- 238000000034 method Methods 0.000 title claims description 23
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims abstract description 157
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 28
- 239000001301 oxygen Substances 0.000 claims abstract description 27
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 27
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 40
- 229910000831 Steel Inorganic materials 0.000 claims description 16
- 239000010959 steel Substances 0.000 claims description 16
- 239000000463 material Substances 0.000 claims description 15
- 238000003608 radiolysis reaction Methods 0.000 claims description 4
- 150000002431 hydrogen Chemical class 0.000 claims description 2
- 239000007791 liquid phase Substances 0.000 claims 1
- 239000012071 phase Substances 0.000 claims 1
- 238000005336 cracking Methods 0.000 description 24
- 238000005260 corrosion Methods 0.000 description 20
- 230000007797 corrosion Effects 0.000 description 20
- 238000011282 treatment Methods 0.000 description 18
- 238000002347 injection Methods 0.000 description 11
- 239000007924 injection Substances 0.000 description 11
- 238000012360 testing method Methods 0.000 description 11
- 239000003112 inhibitor Substances 0.000 description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- 238000000354 decomposition reaction Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 3
- 238000005979 thermal decomposition reaction Methods 0.000 description 3
- 238000011144 upstream manufacturing Methods 0.000 description 3
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- UCMIRNVEIXFBKS-UHFFFAOYSA-N beta-alanine Chemical compound NCCC(O)=O UCMIRNVEIXFBKS-UHFFFAOYSA-N 0.000 description 2
- 238000007664 blowing Methods 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 229910001882 dioxygen Inorganic materials 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 150000002978 peroxides Chemical class 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000005855 radiation Effects 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- OUUQCZGPVNCOIJ-UHFFFAOYSA-M Superoxide Chemical compound [O-][O] OUUQCZGPVNCOIJ-UHFFFAOYSA-M 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 239000013626 chemical specie Substances 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000008094 contradictory effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000003487 electrochemical reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 238000011369 optimal treatment Methods 0.000 description 1
- 239000005416 organic matter Substances 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000003908 quality control method Methods 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F11/00—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
- C23F11/08—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids
- C23F11/18—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in other liquids using inorganic inhibitors
Landscapes
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Preventing Corrosion Or Incrustation Of Metals (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、部材の水素脆化防止方法に係り、特に水また
は水蒸気等の腐食環境中にある鉄鋼材料の水素脆化を防
止する方法に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for preventing hydrogen embrittlement of members, and particularly relates to a method for preventing hydrogen embrittlement of steel materials in a corrosive environment such as water or steam. .
従来原子カプラントや火力プラントなどの発電プラント
における炉水中の配管は、鉄鋼材料で構成されているた
め、腐食からこの配管を守ることが必要となっていた。Conventionally, piping in reactor water in nuclear power plants, thermal power plants, and other power plants is made of steel, so it has been necessary to protect the piping from corrosion.
腐食を防止する方法として従来から次のことが知られて
いる。The following methods are conventionally known as methods for preventing corrosion.
原子炉の炉水中には水の放射線分解により生成した過酸
化水素や溶存酸素が安定に存在する９そこで、これらの
化学種を利用した原子カプラント構成材の腐食抑制方法
が提案され、一部実用化されている。沸騰水型原子炉（
＋１ Ｗ Ｒプラント）における給水系の鉄および鉄基
合金、ｔとして炭素鋼の防食法として特公昭５２−１２
６６４１号に開示されたように、給水中への酸素ガスの
吹き込みまたは過酸化水素の添加により溶存酸素濃度を
５０〜３０（ｌｏＯＰｐｂに調整する方法が存在する。Hydrogen peroxide and dissolved oxygen produced by radiolysis of water are stably present in the reactor water of a nuclear reactor9.Therefore, a method of inhibiting corrosion of atomic couplant constituent materials using these chemical species has been proposed, and some have been put into practical use. has been made into Boiling water reactor (
Iron and iron-based alloys for water supply systems in +1 W
As disclosed in No. 6641, there is a method of adjusting the dissolved oxygen concentration to 50 to 30 (loOPpb) by blowing oxygen gas into the water supply or adding hydrogen peroxide.
この従来技術は、炭素鋼の全面腐食を抑制する方法であ
って。This prior art is a method for suppressing general corrosion of carbon steel.
酸素ガスの吹き込みまたは過酸化水素溶液の添加により
溶存酸素濃度を調整するものである。すなわち、この場
合の腐食を抑制する環境因子は、過酸化水素ではなく過
酸化水素の熱分解により生じた酸素である。これは、原
子炉の給水系配管内に注入された過酸化水素が２８８℃
（給水配管内温度）という高温環境下のために直ちに熱
分解し。The dissolved oxygen concentration is adjusted by blowing oxygen gas or adding a hydrogen peroxide solution. That is, the environmental factor that suppresses corrosion in this case is not hydrogen peroxide but oxygen generated by thermal decomposition of hydrogen peroxide. This is because the hydrogen peroxide injected into the reactor's water supply piping reached a temperature of 288°C.
Because it is in a high temperature environment (temperature inside water supply pipes), it immediately thermally decomposes.
酸素に変わるためである。このほか９発電プラントでも
、鉄鋼材料の水素脆化を防止する必要がある。This is because it turns into oxygen. Nine other power plants also need to prevent hydrogen embrittlement of steel materials.
しかし上記従来例では水素脆化の防止について何ら配慮
されていなかった。However, in the conventional example described above, no consideration was given to preventing hydrogen embrittlement.
従来、鉄鋼材料の水素割れに対するインヒビターとして
は、Ｎ −Ｃｏ Ｃｏ 、 βアミノプロピオン酸な
どが知られている。Conventionally, N-CoCo, β-aminopropionic acid, and the like are known as inhibitors against hydrogen cracking in steel materials.
しかし、上記有機性のインヒビターは、鉄鋼材料である
たとえばタービンブレート等の表面に積層して濃縮する
ため次のような問題があった。However, the above-mentioned organic inhibitors have the following problems because they accumulate and concentrate on the surface of steel materials such as turbine blades.
有機インヒビターがタービンブレード等の表面に濃縮す
ると、たとえば原子力発電プラントにおいてはかかる濃
縮した有機インヒビターが放射線の影響等により分解す
る。この結果分解産物として各種の有機物が炉水中に出
現することになる。When an organic inhibitor is concentrated on the surface of a turbine blade or the like, for example in a nuclear power plant, the concentrated organic inhibitor is decomposed by the influence of radiation or the like. As a result, various organic substances appear in the reactor water as decomposition products.
このために、かえって鉄鋼材料の腐食を促進するという
相反する現象が生じていた。For this reason, a contradictory phenomenon has occurred in which corrosion of the steel material is accelerated.
このような事情から、従来の発電プラントにおいては、
有効な水素脆化防止方法がなく、その結果原子カプラン
トの低圧タービンローターディスクに使用されている２
Ｎ ｊ、 Ｃｒ Ｍ ｏ Ｖ鋼などの低合金鋼に割れ
が生じていることが発見され、その防止対策が５１１急
の課題となっていた。タービンロータのディスク部に見
られる割れは、全て粒界型の割れであり、ディスク部の
キー１１１デなどの隙間部に集中していることから、水
素脆化（水素割れ）と考えられている。Due to these circumstances, in conventional power plants,
There is no effective method to prevent hydrogen embrittlement, and as a result, hydrogen embrittlement is used in low-pressure turbine rotor disks for atomic couplers.
It has been discovered that cracks are occurring in low alloy steels such as Nj and CrMoV steels, and measures to prevent them have become an urgent issue. The cracks observed in the disk of the turbine rotor are all grain boundary type cracks, and are concentrated in the gaps such as key 111 of the disk, so they are thought to be hydrogen embrittlement (hydrogen cracking). .
かかる問題点を解決するために本発明は、簡易かつ迅速
に部材の水素脆化を防止でき、かつ腐食の促進をおこす
恐れのない部材の水素脆化防止方法を提供することを目
的とする。In order to solve these problems, an object of the present invention is to provide a method for preventing hydrogen embrittlement of a member, which can be easily and quickly prevented from hydrogen embrittlement, and which does not cause the risk of accelerating corrosion.
上記目的を達成するために１本発明は腐食環境中にある
部材に発生期の酸素を接触させて部材の水素脆化を防止
することを特徴とする。In order to achieve the above object, the present invention is characterized in that nascent oxygen is brought into contact with a member in a corrosive environment to prevent hydrogen embrittlement of the member.
上記本発明によれば、発生期の酸素が水素過電圧を著し
く高めることになり、その結果水素発生を抑制す、るこ
とかできる、水素抑制の結果水素の母材中への拡散が阻
止でき、そのほか腐食電位を高めることにより水素の発
生を抑制することができる。According to the present invention, oxygen during the generation period significantly increases the hydrogen overvoltage, and as a result, hydrogen generation can be suppressed. As a result of hydrogen suppression, hydrogen diffusion into the base material can be prevented. In addition, hydrogen generation can be suppressed by increasing the corrosion potential.
上記本発明の構成において、部材とは主に鉄鋼材料をい
うが、その他低合金鋼、ステンレス鋼。In the above structure of the present invention, the members mainly refer to steel materials, but also include low alloy steel and stainless steel.
ニッケル基合金であってもよい。It may also be a nickel-based alloy.
腐食環境とは、たとえば鉄鋼材料等の部材が水または蒸
気の環境中にあることを意味するものである。A corrosive environment means that the component, for example a steel material, is in a water or steam environment.
発生期の酸素を供給するためには次のことを考慮しなけ
ればならない。To provide nascent oxygen, the following must be considered:
原子カプラントにおける水素脆化のインヒビターとして
は、電導度やｐＨなどの水質を変化させないものがよい
とされている。これは、腐食反応が電気化学的反応に従
いその律速過程が電導度によって支配されるためである
。As inhibitors of hydrogen embrittlement in atomic couplants, it is said that those that do not change water quality such as electrical conductivity or pH are preferable. This is because the corrosion reaction is an electrochemical reaction and its rate-determining process is dominated by electrical conductivity.
このような水質制御を可能にするものとして。As something that enables this kind of water quality control.
たとえば過酸化水素やオゾンがあり、これらは原子カプ
ラントや火力ブランｌ−の濾水のように極めて純度の高
い水あるいは蒸気への添加剤として最も適していること
になる。よって上記本発明の構成における発生期の酸素
は過酸化水素やオゾンによって生ずる酸素が存在する。Examples include hydrogen peroxide and ozone, which are most suitable as additives to extremely pure water or steam, such as atomic couplant or thermal bran filtrate. Therefore, in the configuration of the present invention, oxygen generated by hydrogen peroxide or ozone is present during the generation period.
特に過酸化水素は。Especially hydrogen peroxide.
タービンブレードの表面に濃縮することや放射線による
分解の問題がなく原子カブラン１−における水素脆化イ
ンヒビターとして何らの支障なく使用することができる
。There is no problem of concentration on the surface of turbine blades or decomposition due to radiation, and it can be used as a hydrogen embrittlement inhibitor in atomic carblan 1- without any problems.
過酸化水素は、外部から注入して、直接部材と接触させ
る。その他、例えば水の放射線分解により生じた過酸化
水素を利用するようなものであっても良い。Hydrogen peroxide is injected externally and brought into direct contact with the component. In addition, for example, hydrogen peroxide produced by radiolysis of water may be used.
過酸化水素およびオゾンを用いて水素脆化を防止するた
めには、過酸化水素等が添加される部材の腐食環境温度
を１般に２００’Ｃ以下にすることが望ましい６２００
℃を超えると過酸化水素の一瞬の分解がおき、その結果
溶存酸素量が著しく増加することがあるからである。溶
存酸素量が著しく増加すると鉄鋼材料などでは腐食の恐
れがある。In order to prevent hydrogen embrittlement using hydrogen peroxide and ozone, it is generally desirable to keep the corrosive environment temperature of the member to which hydrogen peroxide etc. is added to 200'C or less6200
This is because when the temperature exceeds 0.degree. C., hydrogen peroxide decomposes momentarily, resulting in a significant increase in the amount of dissolved oxygen. If the amount of dissolved oxygen increases significantly, there is a risk of corrosion in steel materials.
なお、２００℃以上であっても過酸化水素が安定に存在
する場合がある。例えば、原子炉の炉内のように高放射
線照射環境下では、炉水の放射線分解により生じた過酸
化水素が安定に存在するので、２００℃以上の温度領域
においてもインヒビターとしての効果がみられる。Note that hydrogen peroxide may exist stably even at 200° C. or higher. For example, in environments with high radiation exposure, such as inside a nuclear reactor, hydrogen peroxide produced by radiolysis of reactor water exists stably, so it is effective as an inhibitor even at temperatures above 200°C. .
過酸化水素の濃度は０．０１〜１００ρｐＮの範囲内で
あることが望ましい、０．０１ｐｐ＋ａ以下では充分な
発生期の酸素を供給できないために部材の水素脆化を防
止することができない。一方］、ＱＱｐｐｍを超えると
過酸化水素の、１度の増加に伴って発生する溶存酸素濃
度も増加するため、部材の腐食の恐れがある。したがっ
て、過酸化水素の注入域は必要以上に多くしないことが
望ましいものである。The concentration of hydrogen peroxide is preferably within the range of 0.01 to 100 pN; if it is less than 0.01 pp+a, sufficient nascent oxygen cannot be supplied and hydrogen embrittlement of the member cannot be prevented. On the other hand, if QQppm is exceeded, the dissolved oxygen concentration generated with each increase in hydrogen peroxide increases, so there is a risk of corrosion of members. Therefore, it is desirable that the hydrogen peroxide injection area is not larger than necessary.
上記本発明は原子カブラン１−の低圧タービンディスク
や高圧タービンディスクの水素割れ防［Ｉ農こ有効であ
る６火力発電プラントにおいても同様である。これらの
発電プラントのうち、特に水素割れを発生し易い部分を
選んで本発明を適用することができる。The above-mentioned present invention is also effective in preventing hydrogen cracking of low-pressure turbine disks and high-pressure turbine disks in 6-thermal power plants. Of these power plants, the present invention can be applied to selected parts where hydrogen cracking is particularly likely to occur.
上記本発明は水素割ればかりでなく、応力腐食割れ、孔
食、隙間腐食、全面腐食に対しても適用することができ
る。The present invention can be applied not only to hydrogen cracking but also to stress corrosion cracking, pitting corrosion, crevice corrosion, and general corrosion.
次に本発明に係る部材の水素脆化防止方法の各実施例に
ついて説明する。Next, each embodiment of the method for preventing hydrogen embrittlement of a member according to the present invention will be described.
（実施例１）
本実施例では、過酸化水素による水素割れの抑制効果を
調べるため、過酸化水素濃度及び温度と。(Example 1) In this example, in order to investigate the suppressing effect of hydrogen peroxide on hydrogen cracking, hydrogen peroxide concentration and temperature were investigated.
水素脆化との関係を定荷重法により検討した６過酸化水
１４ ｌｐｐｍ 〜１００ｐｐ＋ｎを含む水温５０〜３
００℃純水中における２ Ｍ ｉ Ｃｒ Ｍ ｏ Ｖ鋼
の水素割れ挙動をカソード分極条件下で求めた。その結
果を第１図に示す６なお、第１図には比較のために過酸
化水素を含まない無処理の場合の結果も記載しである。The relationship with hydrogen embrittlement was investigated using the constant load method. 6 Water temperature containing peroxide water 14 lppm ~ 100 ppm + n 50 ~ 3
Hydrogen cracking behavior of 2 M i Cr M o V steel in 00°C pure water was determined under cathodic polarization conditions. The results are shown in FIG. 16. For comparison, FIG. 1 also shows the results in the case of no treatment containing hydrogen peroxide.
水温５０〜３００℃の範囲内では過酸化水素を含まない
完全脱気水中（図中Ｘ）では、水素割れが生じた。また
過酸化水ｙＡ０．００１ｐｐｍを含むもの（図中Δ）で
も水素割れの発生が認められた。しかし、過酸化水素を
Ｑ、０１ｐｐｎ＋以上含む完全脱気水中（図中０）では
水素割れの発生が認められなかった。Hydrogen cracking occurred in completely degassed water containing no hydrogen peroxide (X in the figure) at a water temperature in the range of 50 to 300°C. Hydrogen cracking was also observed in the sample containing 0.001 ppm of peroxide water yA (Δ in the figure). However, no hydrogen cracking was observed in completely degassed water containing hydrogen peroxide of Q, 01 ppn+ or more (0 in the figure).
このように、過酸化水素が水素割れの発生を抑制するこ
とが明らかとなった。すなわち、第１図中の水素割れ発
生限界線へより上方の斜線部分がより優れた水素割れを
抑制する領域であることがわかる。Thus, it has become clear that hydrogen peroxide suppresses the occurrence of hydrogen cracking. That is, it can be seen that the diagonally shaded area above the hydrogen cracking occurrence limit line in FIG. 1 is a region where hydrogen cracking is more effectively suppressed.
（実施例２）
次に過酸化水素の熱分解特性の試験をおこなった。試験
方法は、オートクレーブに超酸化水素を所定濃度含有し
た水素濃度を入れ、オートクレーブ入口と出口で過酸化
水素濃度およびＯｚ１度を比較することによりおこなっ
た。その結果を第１表に示す。(Example 2) Next, a test was conducted on the thermal decomposition characteristics of hydrogen peroxide. The test method was to fill an autoclave with a hydrogen concentration containing a predetermined concentration of hydrogen superoxide, and to compare the hydrogen peroxide concentration and Oz1 degree at the autoclave inlet and outlet. The results are shown in Table 1.
第 １ 表
備考）滞留時間：１５（１＋
上記第１表に示すように、過酸化水素の熱分解特性は、
１００℃、１５０℃および２００’Ｃでは大部分が過酸
化水素として存在する。しかし２５０℃を超えるころか
ら過酸化水素のほとんどが分解して溶存酸素となる。し
たがって、過酸化水素を用いた場合の処理温度は過酸化
水素が分解しがたい温度である２００℃以下とすること
が望ましい。Table 1 Note) Residence time: 15 (1+) As shown in Table 1 above, the thermal decomposition characteristics of hydrogen peroxide are as follows:
At 100°C, 150°C and 200'C, most of the hydrogen peroxide exists. However, when the temperature exceeds 250°C, most of the hydrogen peroxide decomposes and becomes dissolved oxygen. Therefore, when hydrogen peroxide is used, it is desirable that the treatment temperature be 200° C. or lower, at which hydrogen peroxide is difficult to decompose.
（実施例３）
一時的にも過酸化水素環境に曝された試験片は、始めか
ら純水環境に曝されていたものより破断時間が長くなる
ことが予想される。そこでこれを実証するために本実施
例では所定の熱処理をほどこした試験片を二連りに分け
て、一方は過酸化水素１ ｐｐｍを含む１４０℃の完全
脱気水中に１０時間浸漬処理し、他方は無処理のままと
してこれらの両試験片をカソード分極化で水温１４０℃
の水素割れ試験を実施した。供試材には、原子カプラン
トの低圧タービンディスクに用いられる実機と同一の熱
処理をほどこした２ＮｉＣｒＭｏＶ鋼を用いた。Ｉ＆長
２０００時間まで試験した結果を次の第２表に示す７
第 ２ 表
第２表中の分数は割れ発生率を示し、○印は割れが生じ
なかったことを示す。(Example 3) It is expected that a test piece that has been exposed even temporarily to a hydrogen peroxide environment will have a longer rupture time than a test piece that has been exposed to a pure water environment from the beginning. Therefore, in order to demonstrate this, in this example, a test piece that had been subjected to a prescribed heat treatment was divided into two parts, and one part was immersed in completely deaerated water at 140°C containing 1 ppm of hydrogen peroxide for 10 hours. Both specimens were cathodically polarized and exposed to water at a temperature of 140°C, leaving the other untreated.
A hydrogen cracking test was conducted. The test material used was 2NiCrMoV steel, which had been subjected to the same heat treatment as that used in the actual low-pressure turbine disk of the atomic couplant. The results of testing up to 2000 hours of I&length are shown in Table 2 below.7 Table 2 The fractions in Table 2 indicate the cracking incidence, and the ○ mark indicates that no cracking occurred.
第２表から判るように無処理のものは全試験片が１００
時間以内で破断した６一方、過酸化水素処理したものに
は３０００時間経過後も全く水素割れが認められなかっ
た。すなわちあらかじめ過酸化水素処理をほどこすこと
によって、タービンディスク部のような腐食環Ｊｒｆｆ
ｉに対して優れた耐水素脆性を付与できることが判る。As can be seen from Table 2, all test pieces for untreated specimens were 100%
On the other hand, no hydrogen cracking was observed in those treated with hydrogen peroxide even after 3000 hours. In other words, by applying hydrogen peroxide treatment in advance, corrosion rings such as those on turbine disks can be removed.
It can be seen that excellent hydrogen embrittlement resistance can be imparted to i.
（実施例４）
本実施例では前記実施例２で述べた過酸化水素処理の最
適な処理温度と処理時間の関係を調べるため、過酸化水
素の濃度を一定にして処理時間と処理温度のみを変えて
前記タービンディスクもみ環境条件下で定荷重法により
実験をおこなった。(Example 4) In this example, in order to investigate the relationship between the optimal treatment temperature and treatment time for the hydrogen peroxide treatment described in Example 2, the hydrogen peroxide concentration was kept constant and only the treatment time and treatment temperature were determined. Instead, an experiment was conducted using the constant load method under the above-mentioned turbine disk kneading environmental conditions.
本実施例に使用する処理液には、過酸化水素を１７ｐｐ
ｍ含む完全脱気水を用いた。その結果を次の第：３表に
示す。The treatment liquid used in this example contained 17 pp of hydrogen peroxide.
Completely degassed water containing m. The results are shown in Table 3 below.
第 ３ 表
ｆｆ１３表中の分数は割れ発生率を示し、Ｏ印は割れ未
発生の場合を示す。The fractions in Table 3ff13 indicate the crack occurrence rate, and the O mark indicates the case where no cracks occurred.
上記第３表から判るように処理温度２２０℃で処理時間
が５時間の条件では、全試験片が１００時間以内で水素
割れをおこした。処理温度である２２０℃を２００℃に
下げた場合には、処理時間が５時間のときには３０００
時間経過後も破断が生じなかったが、処理時間が４時間
のときには５００時間以内で全試験片が破断した。処理
時間５時間を変えずに、処理温度を１００”Ｃおよび１
５０℃に下げた場合にはいずれも３０００時間経過後で
あっても水素割れが認められなかったが、８０℃に下げ
た場合にはｔｏｏｏ時間以内で全試験片に割れが発生し
た。このように処理温度が１００℃以下でも、また処理
時間が短くても過酸化水素処理の効果は著しく減少する
。As can be seen from Table 3 above, under the conditions of a treatment temperature of 220° C. and a treatment time of 5 hours, hydrogen cracking occurred in all test pieces within 100 hours. When the processing temperature of 220°C is lowered to 200°C, the processing time is 5 hours and the temperature is 3000°C.
No breakage occurred even after the lapse of time, but when the treatment time was 4 hours, all test pieces broke within 500 hours. Without changing the treatment time of 5 hours, the treatment temperature was changed to 100"C and 1
When the temperature was lowered to 50°C, no hydrogen cracking was observed even after 3000 hours, but when the temperature was lowered to 80°C, cracks occurred in all test pieces within too long. As described above, even if the treatment temperature is below 100° C. or the treatment time is short, the effect of the hydrogen peroxide treatment is significantly reduced.
以上の結果から最適な過酸化水素処理は１００℃〜２０
０℃で５時間以上おこなうことが特に望ましいことが判
る。From the above results, the optimal hydrogen peroxide treatment is between 100°C and 20°C.
It turns out that it is particularly desirable to carry out the reaction at 0° C. for 5 hours or more.
（実施例５）
本実施例では、ＢＷＲプラント運転時におけるタービン
ディスクキー溝部の腐食環境の水質調査をおこなった。(Example 5) In this example, a water quality investigation was conducted in the corrosive environment of the turbine disk keyway portion during operation of a BWR plant.
その結果を次の第４表に示す。The results are shown in Table 4 below.
第 ４ 表
上記第４表によると、キー溝部の腐食環Ｋｔの特性とし
ては高濃度の溶存酸素が存在することおよび各種不純物
Ｎｏ、Ｃｕ、有機物の増加が挙げられる。ＮａおよびＣ
ｕは炉水のキャリオーバーによるもので数ｐｐｔから数
ＰＰｂと極めて微量である。Table 4 According to Table 4 above, the characteristics of the corrosion ring Kt in the keyway portion include the presence of a high concentration of dissolved oxygen and an increase in various impurities No., Cu, and organic matter. Na and C
U is due to carryover of reactor water and is extremely small, ranging from several ppt to several ppb.
これに対して溶存酸素濃度は２０ｐｐｍと大きな値とな
っている７このように溶存酸素、９度が多いのは、次の
ような理由によるものである。すなわぢ、ＢＷＲプラン
トにおいては、炉心に復水を（Ｉｔ：給する復水給水系
に部材（鉄′ａ）の腐食を防止するため過酸化水素が添
加されるにの過酸化水素の添加は、溶存酸素濃度を高め
ることにより鋼材の腐食を防止せんとするものである。On the other hand, the dissolved oxygen concentration has a large value of 20 ppm.7 The reason why there are so many dissolved oxygen at 9 degrees Celsius is as follows. In other words, in a BWR plant, hydrogen peroxide is added to the condensate water supply system that supplies condensate (It) to the reactor core to prevent corrosion of components (iron'a). The aim is to prevent corrosion of steel by increasing the dissolved oxygen concentration.
しかしこれら復水中に含まれていた過酸化水素は炉内で
蒸気となり蒸気温度が３００℃近くなるため、タービン
」二流側でほとんど分解し溶存ｆＩｎ素となる。この結
果溶存酸素濃度が多くなるのである。However, since the hydrogen peroxide contained in the condensate turns into steam in the furnace and the steam temperature approaches 300°C, most of it decomposes on the second stream side of the turbine and becomes dissolved fIn elements. As a result, dissolved oxygen concentration increases.
しかし、水素脆化を防止するためには１発生期の酸素を
用いて水素が母相中に拡散することおよび水素の発生を
防止することが必要である。したがって、ＢＷＲプラン
トにおけるタービンディスク部のような部分における鋼
材の水素割れを防止するためには必然的に蒸気が高圧タ
ービンで仕事をした結果、蒸気温度が２００℃近くまで
落ちる高圧タービン下流であり低圧タービン上流側に過
酸化水素をあらためて添加する必要がある。したかって
水素割れを抑制するためには主蒸気中の過酸化水素が常
時０．０１ｐｐｍ以上になるように過酸化水素を注入す
ることが必要となる。However, in order to prevent hydrogen embrittlement, it is necessary to diffuse hydrogen into the parent phase using oxygen in the first generation stage and to prevent hydrogen generation. Therefore, in order to prevent hydrogen cracking of steel materials in parts such as the turbine disk in a BWR plant, it is necessary to remove hydrogen from the downstream of the high-pressure turbine where the steam temperature drops to nearly 200℃ as a result of the work done by the steam in the high-pressure turbine. It is necessary to add hydrogen peroxide to the upstream side of the turbine. Therefore, in order to suppress hydrogen cracking, it is necessary to inject hydrogen peroxide so that the hydrogen peroxide in the main steam is always 0.01 ppm or more.
なお、従来のＢＷＲの原子炉上流側に過酸化水素を加え
ていたのは給水中の溶存酸素濃度を高めるためであり、
水素脆化を防止することについては何ら改良されていな
いものである。Furthermore, hydrogen peroxide was added to the upstream side of the reactor in conventional BWRs in order to increase the dissolved oxygen concentration in the feed water.
No improvements have been made in preventing hydrogen embrittlement.
（実施例６）
次に本発明に係る過酸化水素の注入による水素割れ抑制
方法をＢ Ｖ／ Ｒプラントの低圧タービンに適用した
実施例について説明する。(Example 6) Next, an example will be described in which the method of suppressing hydrogen cracking by injection of hydrogen peroxide according to the present invention is applied to a low pressure turbine of a BV/R plant.
本実施例で用いられるＢＷＲプラントは、第２図に示す
ような構成からなりたっている。すなわち、復水器１１
は配管により高圧ポンプ８に接続されている。高圧ポン
プ８はフィルタ１２を介して給水加熱器１３に接続され
ている。給水加熱器１３からは復水を供給するための配
管が出ており。The BWR plant used in this embodiment has a configuration as shown in FIG. That is, the condenser 11
is connected to the high pressure pump 8 by piping. High pressure pump 8 is connected to feed water heater 13 via filter 12 . A pipe for supplying condensate comes out from the feed water heater 13.
この配管は原子炉１５に接続されている。原子炉１５を
出た配管は高圧タービン２に接続されている。高圧ター
ビン２からは主蒸気配管６が出でおり、過酸化水素注入
装置９に接続されている。過酸化水素注入袋Ｗ１９から
出た主蒸気配管１６は湿分分離器５に接続されている６
湿分分離器５からは主蒸気配管が出ており、この主蒸気
配管は三つの配管に分れそれぞれ低圧タービン３に接続
されている。この低圧タービン３内にはタービンロータ
リスク４が設けられている。各低圧タービンから出た配
管は、前記復水器１１に接続されている。This pipe is connected to the nuclear reactor 15. The piping exiting the nuclear reactor 15 is connected to the high pressure turbine 2. A main steam pipe 6 emerges from the high-pressure turbine 2 and is connected to a hydrogen peroxide injection device 9. The main steam pipe 16 coming out of the hydrogen peroxide injection bag W19 is connected to the moisture separator 5 6
A main steam pipe comes out from the moisture separator 5, and this main steam pipe is divided into three pipes, each of which is connected to the low pressure turbine 3. A turbine rotary risk 4 is provided within the low pressure turbine 3. Piping from each low pressure turbine is connected to the condenser 11.
各低圧タービン４は１本の軸で発ｌ！機７と接続されて
いる。また、上記湿分分離器５から出た配管の途中には
過酸化水素センサ１０が設けられている。過酸化水素セ
ンサ１０からは制御４０号が出力され、その制御信号は
上記過酸化水素注入装置９に入力されるようになってい
る。Each low pressure turbine 4 generates power from one shaft! It is connected to machine 7. Further, a hydrogen peroxide sensor 10 is provided in the middle of the pipe coming out of the moisture separator 5. A control signal 40 is output from the hydrogen peroxide sensor 10, and the control signal is input to the hydrogen peroxide injection device 9.
次に本実施例の動作について説明する。過酸化水素は、
上記過酸化水素注入袋！ｉ′７９から主蒸気中に所定量
注入されるようになっている。注入量は前記したように
０．０１〜ＬＯＯｐｐｍの範囲に制御する。過酸化水素
の注入は高圧タービン２の下流側であって低圧タービン
４の上流側であることが望ましいものである。この理１
１０よ原子炉１５で発生した蒸気は通常３００℃近くま
で加熱されている。したがって、配゛６圧タービンーＩ
−，流側で過酸化水素を注入すると、はとんどの過酸化
水素が一瞬に分解してしまうことになる。この結果酸素
は溶存酸素となり、原子状の酸素とならないために水素
割れを防ぐことができない。これに対して高圧タービン
２側で蒸気が仕事をすると、蒸気温度はほぼ２００℃近
くまで落ちるため、過酸化水素を注入しても、過酸化水
素の一瞬の分解を防ぐことができる。Next, the operation of this embodiment will be explained. Hydrogen peroxide is
The above hydrogen peroxide injection bag! A predetermined amount is injected into the main steam from i'79. The injection amount is controlled within the range of 0.01 to LOOppm as described above. It is desirable that hydrogen peroxide be injected downstream of the high pressure turbine 2 and upstream of the low pressure turbine 4. This principle 1
Steam generated in nuclear reactor 10 and 15 is normally heated to nearly 300°C. Therefore, the 6-pressure turbine I
- If hydrogen peroxide is injected on the downstream side, most of the hydrogen peroxide will decompose instantly. As a result, oxygen becomes dissolved oxygen and does not become atomic oxygen, making it impossible to prevent hydrogen cracking. On the other hand, when the steam does work on the high-pressure turbine 2 side, the steam temperature drops to approximately 200°C, so even if hydrogen peroxide is injected, instantaneous decomposition of hydrogen peroxide can be prevented.
このような過酸化水素の注入により低圧タービン４のタ
ービンローターディスクにおける水素脆化を防止するこ
とができる。Hydrogen embrittlement in the turbine rotor disk of the low-pressure turbine 4 can be prevented by such injection of hydrogen peroxide.
過酸化水素の濃度は、過酸化水素センサ１０で常時モニ
タされ、そのモニタ（１号が前記過酸化水素注入＋３Ａ
ｆｆｌにフィードバックされる。この結果前記過酸化水
素注入装置では、所定量に過酸化水素濃度を保つ制御が
おこなわれる。The concentration of hydrogen peroxide is constantly monitored by a hydrogen peroxide sensor 10.
It is fed back to ffl. As a result, the hydrogen peroxide injection device performs control to maintain the hydrogen peroxide concentration at a predetermined level.
なお、過酸化水素を復水供給側すなわち復水器１１の下
流側で注入することにより、かかるラインにおける水素
脆化を防１１−することも考えられる。It is also possible to prevent hydrogen embrittlement in this line by injecting hydrogen peroxide on the condensate supply side, that is, on the downstream side of the condenser 11.
しかし、給水加熱器１３において、原子炉に供給される
水の温度が高くなるために、過酸化水素の一瞬の分解の
恐れがある。したがって、ＢＷＲにおける過酸化水素の
注入は蒸気ないしは水温度を考慮して、注入部位を決め
なければならないにのようなことは通常の火力発電プラ
ント、その他の化学プラントにおいても同様である。However, since the temperature of the water supplied to the reactor increases in the feed water heater 13, there is a risk of instantaneous decomposition of hydrogen peroxide. Therefore, when injecting hydrogen peroxide in a BWR, the injection site must be determined in consideration of the steam or water temperature, and this is also the case in ordinary thermal power plants and other chemical plants.
なお、プラントの製作時（組立て前後）や運転時あるい
はプラント定期点検時に過酸化水素処理をおこなうこと
も可能である。Note that it is also possible to perform hydrogen peroxide treatment during plant manufacture (before and after assembly), during operation, or during periodic plant inspections.
以上説明したように本発明にかかる部材の水素脆化防止
方法によれば１発生期の酸素により１部材の腐食に伴っ
て発生した水素の母材中への拡散を阻止できるために、
母材の水ｉ脆化を迅速かつ硼実に防ぐことができる。し
たがって本発明方法を各種プラントに応用した場合には
、プラント内機器の寿命が向上し、かつプラント内にお
ける不慮の事故を防止することができる。As explained above, according to the method for preventing hydrogen embrittlement of a member according to the present invention, it is possible to prevent hydrogen generated during the corrosion of a member from diffusing into the base material due to oxygen during the first generation stage.
Water embrittlement of the base material can be quickly and reliably prevented. Therefore, when the method of the present invention is applied to various plants, the life of equipment within the plant can be extended, and unexpected accidents within the plant can be prevented.
第１図は温度を過酸化水素濃度の関係を示すグラフ、第
２図はＢＷＲ発電プラントの構成図である。
２・・・高圧タービン、３・・・低圧タービン、４・・
・タービンロータディスク、５・・・湿分分離器、６・
・・主蒸気配管、７・・・発電機、８・・・高圧ポンプ
、９・・・過酸化水素注入装置、１０・・・過酸化水素
濃度センサ。
】１・・・復水器、１２・・・フィルタ、１３・・・給
水加熱器、１４・・・配管、１５・・・ＢＷＲ型原子炉
、１６・・・主蒸気配管。FIG. 1 is a graph showing the relationship between temperature and hydrogen peroxide concentration, and FIG. 2 is a block diagram of a BWR power plant. 2...High pressure turbine, 3...Low pressure turbine, 4...
・Turbine rotor disk, 5...Moisture separator, 6.
...Main steam piping, 7.. Generator, 8.. High pressure pump, 9.. Hydrogen peroxide injection device, 10.. Hydrogen peroxide concentration sensor. ] 1... Condenser, 12... Filter, 13... Feed water heater, 14... Piping, 15... BWR reactor, 16... Main steam piping.
Claims (1)
なることを特徴とする部材の水素脆化防止方法。 ２、特許請求の範囲第１項において、前記部材は鉄鋼材
料であることを特徴とする部材の水素脆化防止方法。 ３、特許請求の範囲第１項または第２項において、前記
腐食環境は、水の液相または蒸気の相であることを特徴
とする部材の水素脆化防止方法。 ４、特許請求の範囲第１項ないし第４項のいずれか１項
において、前記発生期の酸素を部材に接触させるのは、
過酸素水素を当該部材に接触させてなることを特徴とす
る部材の水素脆化防止方法。 ５、特許請求の範囲第４項において、直接過酸化水素を
注入することを特徴とする部材の水素脆化防止方法。 ６、特許請求の範囲第４項において、水の放射線分解に
より生成した過酸化水素を利用することを特徴とする部
材の水素脆化防止方法。[Claims] 1. A method for preventing hydrogen embrittlement of a member, which comprises bringing nascent oxygen into contact with the member in a corrosive environment. 2. A method for preventing hydrogen embrittlement of a member according to claim 1, wherein the member is made of a steel material. 3. A method for preventing hydrogen embrittlement of a member according to claim 1 or 2, wherein the corrosive environment is a liquid phase of water or a phase of steam. 4. In any one of claims 1 to 4, bringing the nascent oxygen into contact with the member includes:
A method for preventing hydrogen embrittlement of a member, comprising bringing hydrogen peroxygen into contact with the member. 5. A method for preventing hydrogen embrittlement of a member according to claim 4, which comprises directly injecting hydrogen peroxide. 6. A method for preventing hydrogen embrittlement of a member according to claim 4, characterized in that hydrogen peroxide produced by radiolysis of water is used.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2482686A JPS62182290A (en) | 1986-02-06 | 1986-02-06 | Method for preventing hydrogen embrittlement of member |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2482686A JPS62182290A (en) | 1986-02-06 | 1986-02-06 | Method for preventing hydrogen embrittlement of member |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS62182290A true JPS62182290A (en) | 1987-08-10 |
Family
ID=12148987
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2482686A Pending JPS62182290A (en) | 1986-02-06 | 1986-02-06 | Method for preventing hydrogen embrittlement of member |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62182290A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6156269A (en) * | 1996-03-19 | 2000-12-05 | Konstrutorskoe Bjuro Khimavtomatiki | Method of protecting high-energy machinery from corrosion damage |
| JP2009270175A (en) * | 2008-05-09 | 2009-11-19 | National Maritime Research Institute | Rust prevention method for metallic member |
| EP2626556A1 (en) * | 2012-02-07 | 2013-08-14 | Siemens Aktiengesellschaft | Wind turbine |
| JP2013204342A (en) * | 2012-03-29 | 2013-10-07 | Nippon Telegr & Teleph Corp <Ntt> | Hydrogen embrittlement prevention method |
-
1986
- 1986-02-06 JP JP2482686A patent/JPS62182290A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6156269A (en) * | 1996-03-19 | 2000-12-05 | Konstrutorskoe Bjuro Khimavtomatiki | Method of protecting high-energy machinery from corrosion damage |
| JP2009270175A (en) * | 2008-05-09 | 2009-11-19 | National Maritime Research Institute | Rust prevention method for metallic member |
| EP2626556A1 (en) * | 2012-02-07 | 2013-08-14 | Siemens Aktiengesellschaft | Wind turbine |
| JP2013204342A (en) * | 2012-03-29 | 2013-10-07 | Nippon Telegr & Teleph Corp <Ntt> | Hydrogen embrittlement prevention method |
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