CS273696B1 - Stell especially for turbine blade - Google Patents
Stell especially for turbine blade Download PDFInfo
- Publication number
- CS273696B1 CS273696B1 CS1014987A CS1014987A CS273696B1 CS 273696 B1 CS273696 B1 CS 273696B1 CS 1014987 A CS1014987 A CS 1014987A CS 1014987 A CS1014987 A CS 1014987A CS 273696 B1 CS273696 B1 CS 273696B1
- Authority
- CS
- Czechoslovakia
- Prior art keywords
- content
- steel
- manganese
- sulphur
- turbine blade
- Prior art date
Links
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 25
- 239000010959 steel Substances 0.000 claims abstract description 25
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 claims abstract description 15
- 229910052748 manganese Inorganic materials 0.000 claims abstract description 15
- 239000011572 manganese Substances 0.000 claims abstract description 15
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims abstract description 12
- 230000007797 corrosion Effects 0.000 claims abstract description 12
- 238000005260 corrosion Methods 0.000 claims abstract description 12
- 229910052717 sulfur Inorganic materials 0.000 claims description 9
- 239000011593 sulfur Substances 0.000 claims description 9
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 6
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 4
- 229910052804 chromium Inorganic materials 0.000 claims description 4
- 239000011651 chromium Substances 0.000 claims description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 3
- 229910052799 carbon Inorganic materials 0.000 claims description 3
- 229910052759 nickel Inorganic materials 0.000 claims description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 2
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 2
- 229910052802 copper Inorganic materials 0.000 claims description 2
- 239000010949 copper Substances 0.000 claims description 2
- 229910052750 molybdenum Inorganic materials 0.000 claims description 2
- 239000011733 molybdenum Substances 0.000 claims description 2
- 229910052758 niobium Inorganic materials 0.000 claims description 2
- 239000010955 niobium Substances 0.000 claims description 2
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims description 2
- 229910052710 silicon Inorganic materials 0.000 claims description 2
- 239000010703 silicon Substances 0.000 claims description 2
- 239000010936 titanium Substances 0.000 claims description 2
- 229910052719 titanium Inorganic materials 0.000 claims description 2
- VNNRSPGTAMTISX-UHFFFAOYSA-N chromium nickel Chemical compound [Cr].[Ni] VNNRSPGTAMTISX-UHFFFAOYSA-N 0.000 abstract description 3
- 229910000734 martensite Inorganic materials 0.000 abstract description 3
- 238000005275 alloying Methods 0.000 abstract description 2
- 230000000694 effects Effects 0.000 abstract description 2
- 239000005864 Sulphur Substances 0.000 abstract 3
- 229910018487 Ni—Cr Inorganic materials 0.000 abstract 1
- 239000000654 additive Substances 0.000 abstract 1
- VCTOKJRTAUILIH-UHFFFAOYSA-N manganese(2+);sulfide Chemical class [S-2].[Mn+2] VCTOKJRTAUILIH-UHFFFAOYSA-N 0.000 description 4
- 238000001556 precipitation Methods 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000005496 tempering Methods 0.000 description 2
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 150000004763 sulfides Chemical class 0.000 description 1
Landscapes
- Turbine Rotor Nozzle Sealing (AREA)
Abstract
Description
(57) Řešení se týká oceli, zejména pro turbínové lopatky předposlední a poslední řady nízkotlakého rotoru parní turbíny a případně jiné díly vystavené největším korozním účinkům a značnému mechanickému namáháni. Oedná se o martenzitickou chromniklovou ocel s případnou přísadou dalších legujících prvků, která se vyznačuje velmi nízkým obsahem manganu a siry. Maximální obsah manganu činí 0,12%, spodní obsah manganu je vázán na obsah siry a musí být nejméně třicetinásobkem obsahu siry.(57) The solution concerns steel, in particular for the turbine blades of the penultimate and last series of the low pressure steam turbine rotor and possibly other parts subject to the most corrosive effects and considerable mechanical stress. It is a martensitic chromium-nickel steel with the possible addition of other alloying elements, characterized by a very low content of manganese and sulfur. The maximum manganese content is 0,12%, the lower manganese content is bound to the sulfur content and must be at least 30 times the sulfur content.
CS 273696 Bl di) 2 7 3 696 (13) Bl (51) Int. Cl.CS 273696 Bl (d) 2 7 3 696 (13) Bl (51) Int. Cl.
C 22 C 38/40OJ C 22 C 38/40
CS 273696 BlCS 273696 Bl
Vynález se týká oceli, zejména pro turbínovou lopatku se zvýšenou odolností proti bodové korozi, jež je určena pro použití do teplot 180 °C. Vynález spadá do oboru konstrukce parních turbín.BACKGROUND OF THE INVENTION The invention relates to steel, in particular for a turbine blade with increased resistance to point corrosion, for use up to 180 ° C. The invention falls within the field of construction of steam turbines.
Doposud se turbínové lopatky parních turbín vystavené teplotám do 180 °C vyrábějí z chromových nebo chromniklových martenzitických ocelí s obsahem síry až 0,030 % a obsahem manganu kolem 0,5 %. Tyto oceli se tepelně zpracovávají kalením a popouštěním, přičemž teplota popouštění se vždy volí nad teplotou maxima druhé tvrdosti. Lopatky s tímto obsahem manganu a síry jsou náchylné k bodové korozi, jež se rozvíjí přednostně v okolí sulfidů manganu, přičemž korozní pitting bývá zárodkem následného poškození oceli účinkem koroze pod napětím nebo únavou.So far, turbine blades of steam turbines exposed to temperatures up to 180 ° C have been produced from chromium or chromium-nickel martensitic steels with a sulfur content of up to 0.030% and a manganese content of around 0.5%. These steels are heat treated by quenching and tempering, the tempering temperature being always selected above the maximum second hardness temperature. The blades with this content of manganese and sulfur are prone to point corrosion, which develops preferentially around manganese sulfides, whereby corrosion pitting is a seed of subsequent steel damage due to stress corrosion or fatigue.
Uvedené nevýhody doposud známých ocelí se odstraní ocelí, zejména pro turbínovou lopatku se zvýšenou odolnosti proti bodové korozi s obsahem 0,01 % až 0,1 % uhlíku.These disadvantages of the known steels are eliminated with steels, especially for a turbine blade with increased point corrosion resistance containing 0.01% to 0.1% carbon.
% sž 19 % chrómu, 3 % až 8 % niklu, 0 % až 2,0 % molybdenu, 0 % až 2,0 % niobu, % až 2,0 % titanu, 0 % až 4,0 % mědi a 0 % až 4,0 % křemíku podle vynálezu, jehož podstata spočívá v tom, že horní hranice obsahu manganu v oceli je limitována hodnotou 0,12 %. Spodní hranice obsahu manganu v oceli je limitována třicetinásobkem obsahu síry v oceli.% to 19% chromium, 3% to 8% nickel, 0% to 2.0% molybdenum, 0% to 2.0% niobium,% to 2.0% titanium, 0% to 4.0% copper and 0% up to 4.0% of the silicon according to the invention, characterized in that the upper limit of the manganese content of the steel is limited to 0.12%. The lower limit of manganese content in steel is limited to thirty times the sulfur content of steel.
Výhody oceli, zejména pro turbinové lopatky podle vynálezu spočívají v její zvýšené odolnosti proti bodové korozi a tím ve zvýšení její životnosti, což se týká např. posledních dvou rad lopatek nízkotlakého rotoru parních turbín větších výkonů. Při uvedeném omezení obsahu manganu a síry v oceli je potlačeno vylučování sulfidů manganu primárně z taveniny během krystalizace oceli. Sulfidy manganu precipitují až za nižších teplot, případně až při tváření, z tuhého roztoku v podstatně dispersnější formě než při primárním vylučování. Malý počet hrubších primárně vyloučených sulfidů manganu se příznivě odráží v potlačení náchylnosti oceli k rozvoji bodové koroze, nebo£ se snižuje počet center, kolem nichž se může bodová koroze rozvíjet do větší hloubky. Na dispersních sulfidech manganu se bodová koroze rozvíjí obtížněji, během delší doby a do nepatrné hloubky, takže defekty, z nichž se mohou šířit trhliny účinkem koroze pod napětím či únavy, narůstají do nebezpečného rozměru za podstatně delší dobu. Tím se zvyšuje životnost oceli v podmínkách uvedeného namáhání.Advantages of the steel, especially for the turbine blades according to the invention, consist in its increased resistance to point corrosion and thus in its service life, which concerns eg the last two rows of blades of a low pressure steam turbine rotor of higher output. With this limitation of the manganese and sulfur content of the steel, the precipitation of manganese sulfides primarily from the melt during the crystallization of the steel is suppressed. Manganese sulphides precipitate from the solid solution in a substantially more dispersed form at the lower temperatures, or at the time of forming, than in the primary precipitation. The small number of coarser primary manganese sulfides excreted is beneficial in suppressing the susceptibility of steel to developing point corrosion, since the number of centers around which point corrosion can develop to a greater depth is reduced. On manganese dispersion sulphides, point corrosion develops more difficult, over a longer period of time and to a slight depth, so that defects from which stress cracking or fatigue can spread are increasing to a dangerous extent in a substantially longer time. This increases the service life of the steel under the stresses mentioned.
Příkladem použití řešení podle vynálezu je ocel, zejména pro turbínovou lopatku předposlední řady nízkotlakého rotoru parní turbíny 200 MW o chemickém složení: 0,04 % uhlíku; 12,3 % chrómu; 6,5 % niklu; 0,10 % manganu; 0,007 % fosforu; 0,002 % síry.An example of the use of the solution according to the invention is steel, in particular for the turbine blade of the penultimate row of a low-pressure 200 MW steam turbine rotor having the chemical composition: 0.04% carbon; 12.3% chromium; 6.5% nickel; 0.10% manganese; 0.007% phosphorus; 0.002% sulfur.
Ve stavu kaleném a popuštěném na pevnost Rm'' 1200 MPa, mez kluzu Ep0,2·—'1000 MPa, —2 tažnost A^ 15 %, kontrakci Z'-' 55 % a vrubovou houževnatost 80 Jem vykázala tato ocel více než dvojnásobnou odolnost proti bodové korozi ve srovnání s ocelemi současně používanými.In a state hardened and tempered to a strength Rm '' of 1200 MPa, a yield strength Ep0.2 · -1'1000 MPa, -2 a ductility A ^ 15%, a Z'-contraction of 55% and a notch toughness of 80 Jem, this steel has more than doubled resistance to point corrosion compared to currently used steels.
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CS1014987A CS273696B1 (en) | 1987-12-30 | 1987-12-30 | Stell especially for turbine blade |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CS1014987A CS273696B1 (en) | 1987-12-30 | 1987-12-30 | Stell especially for turbine blade |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CS1014987A1 CS1014987A1 (en) | 1990-08-14 |
| CS273696B1 true CS273696B1 (en) | 1991-03-12 |
Family
ID=5448163
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CS1014987A CS273696B1 (en) | 1987-12-30 | 1987-12-30 | Stell especially for turbine blade |
Country Status (1)
| Country | Link |
|---|---|
| CS (1) | CS273696B1 (en) |
-
1987
- 1987-12-30 CS CS1014987A patent/CS273696B1/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| CS1014987A1 (en) | 1990-08-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6315846B1 (en) | Heat treatment for nickel-base alloys | |
| JPH0563544B2 (en) | ||
| JP6001817B2 (en) | High corrosion resistance precipitation hardened martensitic stainless steel | |
| Sandoz | The effects of alloying elements on the susceptibility to stress-corrosion cracking of martensitic steels in salt water | |
| CN102482743A (en) | High-strength spring steel | |
| US7686898B2 (en) | Creep-resistant maraging heat-treatment steel | |
| US8663403B2 (en) | High corrosion resistance precipitation hardened martensitic stainless steel | |
| EP3061841B1 (en) | Corrosion pitting resistant martensitic stainless steel | |
| CS273696B1 (en) | Stell especially for turbine blade | |
| US20110036471A1 (en) | NiCrMoNb ALLOY WITH IMPROVED MECHANICAL PROPERTIES | |
| KR101789445B1 (en) | Steam turbine rotor | |
| CS274262B2 (en) | Method of forced pices thermal treatment | |
| JP2008127613A (en) | Precipitation hardening type martensitic stainless steel | |
| CS267963B1 (en) | A method of heat treating a turbine blade | |
| ES2770007T3 (en) | High strength, high impact toughness and excellent fatigue strength alloy steel for muddy motor shaft applications | |
| US11788177B2 (en) | Precipitation-hardened stainless steel alloys | |
| JP4508772B2 (en) | Steam turbine rotor repair method, overlay welding material, and steam turbine | |
| JPS60165358A (en) | High strength and high toughness steel for high and medium pressure rotor of steam turbine | |
| CN109576587A (en) | A kind of high intensity antirust martensitic stain less steel | |
| JPH0321620B2 (en) | ||
| STRAUSS¹ | Non-Rusting Chromium-Nickel Steels | |
| JPS62290849A (en) | Rotor for geothermal steam turbine | |
| JPH0251974B2 (en) | ||
| SU1067078A1 (en) | Steel | |
| SU779415A1 (en) | Method of thermal treatment of low-carbon martensite-aged stainless steels |