The First Ukrainian-Hyngarian “Safety, Reliability and Risk of Engineering Plants and Components” Seminar, 11-12 April 2006, Miskolc-Tapolca Strength of.

The First Ukrainian-Hyngarian “Safety, Reliability and Risk of Engineering Plants

and Components” Seminar, 11-12 April 2006, Miskolc-Tapolca

Strength of Materials and Life of

NPP equipments

Dr.sc. Alexander BalitskiiKarpenko Physico-Mechanical Institute, NAS Ukraine

The percentage of electricity generated by NPP

(on 01.01.2006)

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Nuclear share %

Lithnia

France

Belgium

Slovakia

Bulgaria

Ukraine

Sweden

Slovenia

Armenia

Switzerland

Korea

Hyngary

Japan

Germany

Finland

Spain

Czech R

UK

USA

Russia

Canada

Romania

Argentina

S.Africa

Mexico

Netherlands

Brazil

India

Pakistan

China

UKRAINIAN NPP AND CHARAKTERISTICS OF ITS MAIN

EQUIPMENTon 01.01.2006

UKRAINIAN NPP AND CHARAKTERISTICS OF ITS MAIN

EQUIPMENT

Eastern Europe: nuclear power station

Eastern Europe: nuclear power station

Eastern Europe: nuclear power station

Japan: nuclear power station

Switzerland: nuclear power station

Belgium: nuclear power station

Spain, Italy:

nuclear power station

Reactors age

Example of starting PLEX Procedure

• NPP Surry-1 (2003-2013) (PWR)

• NPP Monticello (2001-2011) (BWR)

• Yankee NPP (PWR) (1991-2006)

• Bilibino-1 (2004-2019) (LWGR)

• Kola-1 (2003-2018) (PGW-440)

• Nowoworonez-1 (2001-2016) (PGW-440)

NPP with BWR reactor:1 – reactor shell; 2 – fuel elements; 3 – regulative rods;

4 – moving devices of regulative rods; 5 – water circulation pomp; 6 – fresh steam; 7 – quiring water; 8 – high pressure turbine; 9 – low

pressure turbine; 10 – turbogenerator; 11 – turbogenerator exiter; 12 – capasitor; 13 – water from river; 14 –water heating devices; 15 –

feeding water pomp; 16 - cooling water pomp, 17 – concrete defence.

NPP with PWR reactor: 1 – reactor; 2 – fuel elements; 3 – regulative rods; 4 – moving devices of regulative rods; 5 –

pressure stabilizator; 6 – steam generator; 7 – first circle water pomp; 8 – fresh steam; 9 – quiring water; 10 – high pressure turbine; 11 – low pressure turbine; 12 – turbogenerator; 13 – turbogenerator

exiter; 14 – capasitor; 15 – water from river; 16 – feeding water pomp; 17 – water heating devices; 18 – concrete defence; 19 – cooling

water pomp

NPP with high temperature THTR reactor with granular fuel:

1 – reactor;

2 – graphite reflector;

3 – steel screen;

4 – steam generator;

5 – cooling gas (helium)

ventilator;

6 – concrete

building;

7 – regulative

rods; 8 – exite pipe of using fuel; 9 – entrance pipe of fuel; 10 – cooling

gas (helium)

Sheme of 1st contour sirculation lupe of nuclear reactor vessel PWR (Westinghouse(a),

Babcock & Wilcox (b)): 1 – pressure stabilizator, 2 – steam outlet on turbine, 3 – stem generator, 4 – main circulation pump, 5 – reactor

active area, 6 – reactor core, 7 – cooling loop, 8 – entrance of

nourishing water from a condenser

The persentage of accidents risk (N, %) on NPP equipments: steam generators

(SG), heat exchange system (HE), turbogenerators (TG), reactor equipment (R),

electrosystem of water intrance and accompained equipment (W)

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SG HETGRWS

Chornobyl-4 (Safety of “Shelter”)General wiew of object of “Shelter”: a – cutting on the L

axis; b – cutting on an axis 47; 1 – blocks of B1 and B2 beams; 2 – beam “Mammoth”; 3 – beam “Vosminig”

Chornobyl-4 (strategy of stabilization of “Shelter” )Reinforcement of existing metal structures by making an extensive use of welding of West

fragment of “Shelter”

Chornobyl-4 (Long term stabilization)

Beam “Mammoth”

Possible PLEX procedure on “Shelter”

• If the full replacement of the damaged structural elements

is impossible, the technologies of their restoration became

important using the modern concepts of fracture mechanics

the injection processes of crack-like defects in NPP structural

elements: for example – basin of self-controls and overloads

of the worked nuclear fuel) • The elastic and strength properties of the matrix (concrete)

and the polyuretane - based fillers in crack-like defects of

concrete structures allows to restore the structure carrying

ability by 50-80 %.

Depository for the blasted reactor

of Chernobyl-4 NPP (weighing 20 thouth. ton)

Chemical composition of structural steels, coatings and welding wires, which used for

pressure vessel of ligh pressure water reactors on Ukraine and Russian NPP.

Mechanical characteristics of Ukrainian and Russian structural steels, coatings and welding wires,

which used for pressure vessel of ligh PWR

The integrity of RPV steels determines the safety and lifetime of

NPPs and must therefore be guaranteed for ~40

years (at least…) RPV steels are known to

harden and embrittlement under

neutron irradiation and this may put their

integrity during operation in danger

Future reactors: Accelerator driven sub-critical Accelerator driven sub-critical

FusionFusion

Main candidate structural material: FMMain candidate structural material: FM

The neutron fluence and fatigue damage distribution through WWER-440 height: N – cycles quantaty during full project resource of

construction, [N] – quantaty of cycles to failure according PNAE (I); Cover of WWER-440 RPV and separate units joining different nozzles with

sphere:a : 1 – surfacing “I”; 2 – surfacing

“E”; 3 – in cross-section are shown shematically;

4 – elec troslag weldment № 1; 5 – sphere; 6 – electroslag weldment №2; 7 – flange;

8 – surfacing “Zh”; 9 – branch pipe ЗВ; 10 – branch pipe TK;

11 – branch pipe ARK; b: 1 – upper flange of ARK cover;

2 – weldment weldment №7; 3 – pipe Ø273; 4 – weldment

№5; 5 – adapter; 6 – weldment №4; 7 – pipe; 8 – weldment №3; 9 – weldment №2; 10 –

weldment №1; 11 – down flange of ARK cover.

1 – weldment №25; 2 – surfacing “Р”; 3 – weldment №18; 4 – sphere; 5 – flange;

6 – surfacing “П”; 7 – weldment № 24; 8 –

weldment № 28; 9 – pipe; 10 – protective housing; 11 – heat tension member (c);

1 – weldment “С”; 2 – surfacing “Т”; 3 – branch

pipe; 4 – weldment № 19; 5 – weldment № 3; 6 – weldment “Е”; ; 7 –

protective housing; 8 – surfacing “Д”; 9 – weldment

№ 20 (d)

Temperature control by “Termoprylad” (Lviv, Ukraine)

sensorsControl of parameters in the WWER-440 reactor,

basic reactor equipment: I – overlay; II – corps; III – active area; IV – corps fastening; V – dry defence; VI –concrete mine. Controlled parameters: 1 – temperature of reactor flange; 2 – temperature of overlay flange; 3 – temperature of heat transfer agent on an exit from a reactor; 4 – concentration of boric acid on the entrance to the reactor; 5 – water level in a reactor; 6 – temperature of heat transfer agent on ther exit from cassettes; 7 – temperature of heat transfer agent on the entrance to the reactor; 8 – temperature of fastening; 9 – temperature of dry defence; 10 – concrete temperature; 11 – energy irradiation on height of the active area; 12 – energy irradiation on the radius of active area; 13 – temperature of heat transfer agent on the entrance in an active area; 14 – concentration of boric acid on the entrance in an active area; 15 – appearance of water in a mine; 16 – temperature of reactor corps

Effect of service time on intergranular stress corrosion crack depth detected in pipes (mostly in weld heat affected zones)

(boiling water reactors, 280–290 ºC): 1 – KKB (Kernkraftwerk Brunsbüttel), 2- KWW (Kernkraftwerk

Würgassen) , 3-GKT (Grosskernkraftwerk Tullnerfeld) (in Austria, has been built but not operated), 4- KKK (Kernkraftwerk Krümmel), 5 - KKI 1, 6 - KKP-1

(Kernkraftwerk Philipsburg), 7- Chernobyl

PLEX procedure of reactor core

• PTS – pressurized thermal shock• ADP – Annealing Demonstration – Midland

NPP (BWR), Marble Hill NPP• Sufery Guide 50-SG-012• Code of Federal Regulation 10 CFR 54• Licence Renewal Rule• ISI-requirements of the ASME Code

Section

Location and shape of steam generator parts fabricated from alloy

6001 – vessel head nozzle

; 2 – core support pad item M;

3 – bottom head penetration;

4 – distribution plate (f.s.); 5 –

tube sheet; 6 – partition plate

(f.s.); 7 – outlet nozzle; f.s. – ferritic steel

WWER-1000 steam generator in operation and their damage

NV5 – Novovoronezn 5; SU1 – South Ukraine 1; SU2 – South Ukraine 2; Z1 – Zaporizhe 1; K1 – Kalinin 1; Z2 – Zaporizhe 2; B1 – Balakovo 1; Z3 – Zaporizhe 3; K2 – Kalinin 2;R3 – Rivne 3; B2 – Balakovo 2; Z4 – Zaporizhe 4; Kh1 – Khmennitski 1; Kz5 – Kozloduy 5; B3 – Balakovo 3; Z5 – Zaporizhe 5; SU3 – South Ukraine 3; Kz6 – Kozloduy 6; B4 – Bala kovo 4; Z6 – Zaporizhe 6; T1 – Tamelin-1; Rs1 – Rostov 1; T2 – Tamelin 2

Damage locations at SG III cold collector of South Ukraine-1 (a), Zaporozhe-2 (b), Zaporozhe-1 (c), South Ukraine-2 (d) NPP. ◆ – Area of faulty holes (ligaments)

according to instrument readings

Maximum crack growth rates of intergranular SCC nickel-base alloys and steel in water with oxygen content ≤ 20 ppb, conductivity ≤ 0,6 µS/cm at the

temperature 288ºC plotted versus yield strength (a): 1 – 316 NG, 2- Nim 70, 3 – A 286, 4 – Nim 80A, 5 – X-750, 6 – IN 600, 7 – IN 600, 8 – IN 718, 9 – SCC

service failure of a bolt, alloy ChN35VT (Table 4.3, 4.4), WWER-440 and comparison an actual SCC servise failure in nuclear power plant for different

alloys measured in PWR primery water, 350ºC(b):

Technological process of HEP repair e:a – common scheme, b – electrode opening to the length of the strengthening layer, c – electrode opening, d – electrode opening, e –

electrode opening, f – electrode opening, g – cleaning, h – washing, k – electro polishing, l – washing, m – activation, n – washing, o – coating of barier layer,

p-coating of barier layer, q – coating

of strengthening layer, r – coating

of protective layer, s – coating of

protective layer, t – washing, u –

finish of technological process; 1 –

-detected deffect, 2 – cleaning solution,

3 – washing solution, 4 – electro polish

solution, 5 – activation solution, 6 –

barier sleeve forming from soft Ni, 7 –

electrolite Ni, 8 – sleeve forming from

alloy Ni-Co, 9 – protective coating

Effect of yield strength (a):1 (▲) – Rp0,2= 1240 MPa; 2 (●)

– Rp0,2 = 1190 MPa; 3 (■) – Rp0,2= 756 MPa, content of

oxygen in water (b): (■) – < 0,01 ppm [O2], no CO2; (●) –

0,1 ppm [O2], 100 ppm [CO2]; ▲ – 8 ppm

[O2], 0,7 ppm [CO2], fracture toughness

(c): 1 – KIC = 200 MPam(as received);

2 – KIC= 197 MPam (as received+step

cooled); 3 – K1C = 110 MPam (as received+450oC/104h); degree of temperature embrittlement (d): 1 – 3%Ni steel; 2 – 2Cr –1Ni steel; 3 –“clean steels” on the stress corrosion crack growth rates of steam turbine rotor steels exposed in water at 100 C (a,b,d), 160 C (c,d) and 288 C (d)

Effect of stress intensity (a), yield strength (b) on the growth rates of intergranular stress corrosion cracks in steam turbine rotor steels in water at 160 ºC (a) and 100

ºC (b) and two different temperatures (c) as well as reciprocal temperature (d).

(a): 1 – 3–3,5% Ni steel; 2 – 2Cr-1Ni

steel; 3 – “clean steels”, specially alloyed

steels. (b): R P 0,2 , MPa: 1 – 1456, 2 –

1289, 3 – 1278, 4 – 1266, 5 – 1211, 6 –

1186, 7 – 1138, 8 – 1053, 9 – 1027, 10 –

1002, 11 – 966, 12 – 926, 13 – 861, 14 –

731. (c): 1 – clean rotor steel, 2 –

commercial rotor steel. (d): R P 0,2 ,

MPa: 1 – 1350, 2 – 1211, 3 – 1190,

4 – 800

Fatigue crack growth diagrams of rotor steel 38ХН3МФА

(near threshold and Paris

areas) after standard heat

tratment: 1, 2, 3 – electrolityc

hydrogenation with current

density 1 А/dm2; 4, 5, 6 –

on air; 1, 4 – loading

frequency – 2 Hz; 2, 5 –

10 Hz; 3, 6 – 50 Hz

Damage locations at steam turbine condensator pipes (◆) of South Ukraine –1

NPP according to instrument readings -2003 and risk of engineering plants.

Corrosion damage of condensators

piping made from Cu-alloys (X %)

dependance of time:1 – Sn-brass;

2 – Al-brass, 3 –Al-bronze; 4 – Cu-Ni

Accidents with rotors and retaining rings of powerfull turbogenerators:

1 – a number of rotors failure (1,5Cr-3,4Ni-0,5Mo-0,6V steel); 2 – a number of retaining rings failure (8Mn-8Ni-4Cr; 5Cr-25Ni-2,5Ti;

18Mn-4Cr, Ti-6Al-3Mo steels and alloy); 3 – a number of shut down energy units with output 200 MW

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Increasing of electric machines output

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Output W, MW

HSM-0,23PP-0,5SDG-12,5T3VTVV-210TVV-320TVV-500TVV-800TV-1000TVV-1500

Turbogenerators ТVV-500-2 (Electrosila) (output – 500 MW, voltage – 20 kV, frequency – 50 Hz, rotating speed – 3000 RPM) with brushfree exciter (а)

and TOPAIR 23 (ABB Alstom) (output – 270 МW, voltage – 19 kV, frequency – 60 Hz, rotating speed – 3600 RPM)

Equivalent (with regard for fretting) stresses on turbo-generator rotor

shaft. 1 – ТВВ-220-2; 2, 2а – ТВВ-1200-2, correspondenly, in original design and

after арplication antifretting

measures; 3, 3а – Т3В-800-2; 4, 4а –

ТВВ-500-2; 5 –

safety level (b)

Fracture surface of turbogenerator ТВВ-1200-2 rotor (a)), appearance of the surcumferential crack on the

turbogenerator ТVV-320-2 rotor (mounting surface for contacting rings, tratsition fillet behind 7 and 8 bearing) (Hacko energy unit, Bosnia and Gertsogovina) (b), and its

propagation in the axial direction (c).

Dobrotvir-12, March 2006

Dobrotvir-12, March 2006

Dobrotvir-12, March 2006

Dobrotvir-12, March 2006

Dobrotvir-12, March 2006

Dobrotvir-12, March 2006Hardness of rotor and retaining rings

surfaces

SCC crack growth curves of retaining ring materials in 22 % NaCl solution at 105оС, aerated 1 – UKR,

2 – alloy Ti 6-2, 3 – P900, 4 – P2000, 5 – alloy 33

Effect of temperature, environments, chemical composition, crack orientation and stress intensity of SCC

growth curves of retaining ring steel 18Mn–18Cr

The addition of chlorides can greatly accelerate the growth rates of SCC in retaining ring steels P 900 (Fe-18Mn-18Cr-0,6N) (a): 1 – 22%NaCl solution, aerated, 2 – pure water, aerated, and SCC growth rates estimated

by dividing the total crack depth by the total service time of the affected generator rotor retaining rings: FPP Perm-1 (PI), Perm-II (PII), Perm-III

(PIII), Rjazan (R), Porto-Tolle (PT) in pure water and in 22%NaCl solution (b)

KIC – T diagrams (™ – KJC, – KIC)

(а) (in air), Kfc – T (b), Kth – T (c)

(electrolytical hydrogenation with current density 100 А/m2) of steels for rotor-retaining ring unit: 1 – 3,5NiCrMoV; 2 – 8Mn8Ni4Cr;

3 –1 8Mn 4Cr; 4 – 18Mn18Cr

CONCLUSIONSFactors combination, which necessary and sufficient for creation of phenomenon of corrosion, fatigue, contact-

selective stress corrosion cracking and corrosion fatigue in high strength steels and their welding joints

1 – scale effects, 2 – protective coatings

and passive films, 3 – surface modifications,

4 - microstructure, 5 – mechanical-, 6-

thermal treatment, 7 – electroslag

remealting, 8 – chemical (ionic)

composition of corrosion products,

9 – temperature, - 10 – potential,- 11 –

pH value, 12 – adsorbed layers, 13 –

fluid speed and pressure, 14 –

deformation rate, 15 – anisotropy, 16 –

residual, 17 – constructive, 18 - service

stresses