ML20040H115
| ML20040H115 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 11/30/1981 |
| From: | ALLIS-CHALMERS CORP. |
| To: | |
| Shared Package | |
| ML20040H112 | List: |
| References | |
| ER-8102, ER-8102-R01, ER-8102-R1, NUDOCS 8202170202 | |
| Download: ML20040H115 (19) | |
Text
As a a==-chat Merne powan sysTurma,wwc.
c ENGINEERING REPORT ER-8102, Revision 1 CRITICAL CRACK SIZES OF COMANCHE PEAK LP TURBINE DISKS November,1981 PIIOMettfAlw tN F0fmA AT10N OF ALLIS-CH ALMERS POWEft SYSTEMS.lNC.
, Not to be reproduced, copied or dieseminated without the onprose prior veritten consent of Altie-Cheimere Power Systems, Inc.
i 8202170202 820210- ..
1 ER-8102 (11/81) R ;v. 1 #"""* "" *"" N r 3 CRITICAL CRACK SIZES OF COMANCHE PEAK LP TURBINE DISKS Critical Crack Evaluation Evaluations of the critical crack sizes a chave been performed for disks #1 through #5 of the four LP turbine flows of the Comanche Peak units under the following assumptions:
- 1. The stress calculations for the disks of the Comanche Peak LP turbines were performed by utilizing finite-element computation to determine the stress distribution within the disks.
- 2. In particular the calculations of the local stress concentrations at the keyways are based on this finite-element computation. The evaluation considers the plastic deformation in the vicinity of the keyway during the overspeed test at 125% rated speed. This plastic deformation was the base to define the stress distributions in the keyway vicinity at rated and 120% speed. The resulting stresses are the basis for the evaluation of the stress intensity.
- 3. Evaluation of the relationships of the stress intensity versus the crack depth was performed by an analytic method utilizing the WESTERGAARD functions or the integration method BETSY, both of which are computer programmed.
Figure 1E81.137 shows the typical stress distribution in the immediate vicinity of the keyway after the 25% overspeed test. It can be seen that after reaching a peak at a crack depth of about one-half inch the stress decreases with increasing crack depth. The stress intensity, however, shows a sustained increase as the crack grows. While the above figure shows only the tendency 1
L >
1 ER-8102 (11/81) Rev.1 r 3 l 1
1 of stress and stress intensity of disk #5 for rated speed operation, the actual results for all five disks at rated speed and 20% overspeed are depicted in the attached drawings 1E81.200 through IE81.209.
- 4. All fracture toughness values were calculated in accordance with the method defined by ROLF & NOVAK from the yield strength test and the notch impact test minimum results as measured on each specific disk. The maximum and minimum values shown in Figure IE81.159a are derived from tests on the Comanche Peak disks of units 1 and 2. The maximum values for disk #1 reflect the best of all the minimum values from all eight #1 disks of the two Comanche Peak 4-flow units. The minimum values are the lowest mechanical properties measured in any of the eight #1 disks. The same method was used for disks #2 through #5. It is of importance that the yield strength and notch impact tests were performed at 20'C (68 F) ambient temperature and some even at -200 C (-40F). No corrections were performed for the actual operating temperature.
- 5. Shown in Figure 1E81.159a are the resultant critical crack sizes for the Comanche Peak LP turbine disks. Minimum and maximum values are given for rated speed and 20% overspeed. The calculation assumes a crack shape with a craak length L which is fout- times larger than the crack depth (a=l/4L).
Minimum and maximum crack depths are derived from the minimum and maximum fracture toughness, respectively. Calculations up to a crack of 100mm or 3.94 in. were performed. Critical crack depths in excess of 3.94 in, are tabulated as 3.94 in, cracks. Critical crack depths were calculated and are listed for the keyway and hub vicinity of the disks.
2 L >
ER-8102 (11/81) Rev.1 r 3 Data to Assess Crack Growth For evaluating stress-corrosion cracking and crack growth risks, design features and manufacturing methods should be taken into consideration. The manufacture and quality assurance for our disk-type rotors have been described in our engineering report, ER-504, which includes the horizontal shrinking procedure. The lubricant used during the shrink-on process of the Comanche Peak disks was DAG156 purchased from the Deutsche Acheson GmbH in Ulm, West Germany.
The lubricant is a product of the U. S. Acheson Company in accordance with the U. S.
specification MIL-L-24131B. It is a graphite-base lubricant with an isopropyl alcohol -
binder and specified solid substance of 3.3% 10.5%. Maximum values of specified compositions within the solid substance are:
Ash 0.75 %
Fluorine 20 PPM Chlorine 200 PPM Sulfur 200 PPM Lead 150 PPM The shrunk-on disk and the locking pin design are depicted in Figure 1E81.160 indicating that only the disk center, about 60% of the disk hub width, provides the actual shrink fit. The locking pins and their keyways are actually aside from the shrink fit providing a shrink fit area without any stress concentration. Five locking pins are provided equally spaced on the circumference of the disks' exhaust sides. After the disks are shrunk on, the 20mm keyways for the 5 locking pins are drilled into the shafts and disks. To eliminate high stress concentrations at the bottom ends of these keyway bores,larga radial relief grooves have been machined in both the disks and shaf ts, as shown in Detail 3
k >
As n -csauwerne a=owarn everarnee.nwc. ^
. ER-8102 (11/81) Rev.1 r 3 A of Figure 1E81.160. The large-radius relief grooves not only minimize the stress concentration at the keyway bottom ends but also provide an area without shrink fit in the keyway vicinity.
To assess stress-corrosion of the Comanche Peak LP turbine disks, it is important to note that we have inspected nuclear turbine disks in the past without finding a single disk crack.
For the performance of stress-corrosion crack-growth evaluations, the calculated steady-state metal temperatures at the shaft-to-disk shrink fit during operation of the Comanche Peak unit with rated steam conditions are:
Disk 1 Admission / Exhaust 3560 F/284 F Disk 2 Admission / Exhaust 2840 F/2250F Disk 3 Admission / Exhaust 2250 F/1920F Disk 4 Admission / Exhaust 192 F/1580F Disk 5 Admission / Exhaust 1580 F/167 F Attachments: Drawings: 1E81.137 1E81.159a 1E81.160 1E81.200 through 1E81.209 4
k i
(
l
.l REylSION.
f/204A b -
l Stress d C
d Stress intensity K i m
n r.
i o !!
il hil i BE Il {,
Eg Ip "
iis 4'5 lj ilj " '
j ,
2 3 4 jg P,j v 1/2 si 25- Crack Depth a(in.)
is :j$ Keyway
(( bi Diameter 0.79 in.
I
! STRESS AND STRESS INTENSITY VERSUS CRACK DEPTH IN T.T"."OO m KEYWAY VICINITY OF NUCLEAR LP TURBINE DISK #5 AT RATED SPEED 1E81.137
Tangential Stresses at Disk Hubs for Various Speeds in Kal:
/ NPD Tl Disk #1 Disk #2 Disk #3 Disk #4 Disk #5 0 9//r97 b Zero Speed 60.5 61.9 56,1 61.3 59.3 C Rated Speed 76.4 80.0 71.8 79.3 77.3 d -
1.2 x Rated Speed 83.4 88.0 78.7 87.2 85.1 t ,
l .
' Fracture Toughness Min. and Max. Values
from Measurements on all Comanche Peak Units 1 and 2 *
.t LP Turbine Disks in KslG:
} Disk #4 Disk #5 Value Disk #1 Disk #2 Disk #3 Min. 171 173 202 173 176 L Max. 223 224 227 215 213
\
ll Critical Crack k, .ns a cat the Keyways fdr l Min. and Max. Values of Fracture Toughness in inches:
Min./ Max. Value Disk #1 Disk #2 Disk #3 Disk #4 Disk #5 l
Rated Speed 1.38/2.91 1.34/2.80 2.60/3.66 1.46/2.64 1.89/3.31 1.2 X Rated Speed 1.10/2.36 1.06/2.20 2.05/2.87 1.14/2.09 1.46/2.52
]} '
l j!
l i5 5 Critical Crack Depths ac at the Disk Hubs for
- . a B! liN[g Min. and Max. Values of Fracture Toughness in lachss
rv al Disk #3 Disk #4 Disk #5 jg, )gi,} Min./ Max. Value Disk #1 Disk #2 bjy Rated Speed 1.93/3.35 1.81/3.07 3.07/3.94 1.85/2.87 2.05/2.99 18 a ; . 1.2 X Rated Speed 1.65/2.80 1.50/2.52 2.56/3.23 1.57/2.44 1.69/2.48
$ N ing Ed !d CRITICAL CRACK SIZES auA c~~~==
~ " " " " " ' " ~ ~
OF COMANCHE PEAK LP TURBINE DISKS 1E81.159a
Radius:
R10 = 0.39 in.
- -- w - - -- m R22.5 = 0.89 in.
Dianieten u FB
(
EvisION --
q hwp __!}__)
b 5 ( M in
_ _ __jl V
C !
208 w -
- - - - - _._ f l
-- Detail A r... .. 4 l
Y 5 Locking
/ N A Pins i /ig-l3- [,_
l s _.
l i'
i x g./' , ,
i u-'li ,/ \.
1 r5i}s!! j.5 -
-E Z~N f '# -
3 i lh'[ N E@d 3 ' .]
"s 8p <
[A Shrink Fit Section B-B H hi s___.-<
, 5 Disk #5 1
LOCKING PINS AND agch=L KEYWAYS OF LP TURBINE DISKS 1E81.160
--- =. _ _ ,
.e ifV ~~ i ,'_
'r 's 3, '. ' _ f :s >
-] ,
Kg g "I I (N/mm ) (N/mmt)
(Ksi M ) (Kst) :
300--150 seese.. -1000 V REVISION
/ IHtr Tt .. .
0 stress G
/,,,g /
b \
C 200.-100 '\ Stress intensity Kg d 's
, .. . s,
,' N ,
--500 - -' '%
'~~~~ -. .,____
sees.o 100- 50 see...
1.0 2.0 3.0 4.0 (in.)
0 -0 *' ' '
ig;g- i,'g ,; -
i-
,,g .g , g-9;- ig;,-
Crack Depth a 533.0 585.0 900.0
- l. i j!
i5 0
- al~i s!!ij Nuclear LP Turbine EE $N~
5" 4 *i Disk Type Rotors:
I **I Comanche Peak and Grand Gull h }8:Ej, i382'j
$$ =
El BI$
ge s e s a< zl4 STRESS AND STRESS INTENSITY m,,,c_, _
VERSUS CRACK DEPTH IN = = = v = r= = =
KEYWAY VICINITY OF DISK #1 AT RATED SPEED 1E81.200 i
l Is I K d I (N/mmT). (N/mmt)
(KolM.) (Kal) .
sa in . sos.. _2000 RNSION.
/////rW eeee.e . ,A
/ Stress d
,y b
, \
Stress Int ensity Kg C 200--100 d
\s g eene.e \N
-500 ~~*%,, ,
nees.e .
100--50 sees.e 1.0 2.0 3.0 4.0 (In.)
s-
- e s' Se e.e 0--0 - .
%.e-
,me.e
,ee.e e s.e-- (mm) s.e Crack Depth a 544.0 607.0 900.0
- 3. .a.
d Ib 3.!*J s ais g* j i '
Nuclear LP Turbine 25
@a ,1? )!
< 1 Disk-Type Rotors:
!y j -l{
a g ',
Comanche Peak and Grand Gulf j3 t,j 17r l'a 5b 8lk Es hi STRESS AND STRESS INTENSITY ALL.es-CHAL MEast
.-ow a -v-rn- .~c VERSUS CRACK DEPTH IN KEYWAY VICINITY OF DISK #2 AT RATED SPEED 1E81.201
Kg g Kg , g (Ksl G.) (Ksi) (N/mmT), (N/mmt)
- 300- -150 mee.e . 1000 REVISION
/
o e.
b C
d g
200--100 .
/q\ / stress #
\
\
\
,,,,,, , Stress Intensity Kg
'\
_ --500
.,,,~~~.. _
_ seee.e . ~-~~...__~~~~- . _ _ ,
! 100--50 ee .. .
0--0 e.e y 2;0 3;0 4;0 On.)
'e ' e'
. ~ 'si.e ~ .' i.e ~'.e~ ~ ' .e . , ~'~
~'ei.e~
(mm)
Crack Depth a 506.0 562.0 780.0 3a i?~l d Eb 1 ..
4BSE o' I
=
$=
28!
,Ej Nuclear LP Turbine
! Disk-Type Rotors:
Comanche Peak and
'a3.
g, Grand Guif e e.
5526;.
l Es 819 a9d< sEE 21 <
j 1
STRESS AND STRESS INTENSITY VERSUS CRACK DEPTH IN T.700t~r.""". .
KEYWAY VICINITY OF DISK #3 AT RATED SPEED -
1E81.202
Kg g I U (N/mm2)
(Kal VTR.) (Kel) (N/ mmh)
--- 300- -150 ossee.e . -1000 REVISION
/////r a
n **** ' - -
/3 t Stress G b
C b/ \,f \
d
_ :- 200--100
\g Stress Intensity Kg e I - -
g ..
f -
500 N
^
lf 100--50 a
'l
- .ees.. .
2 i
1.0 2.0 3.0 4.0 (In.)
0--O e.e >
s '.e ~ M .'e' ~ b.e' .'.
~ Mie ' 'ee.e _ 'se.e.e (mm) r Crack Depth a 531.9 592.0 440.0
$. 3*
f .g d Eb t 5. "3 se E E5 IJ Nuclear LP Turbine 3 gg 2g }gg! Disk-T'ipe Rotors:
F En .i
[ }=j g Comanche Peak and Grar.d Gulf e ire
~
gE ag e 55
- og a v.
N8lk Ed bi .
I STRESS AND STRESS INTENSITY AL.Lo.-CHAL MEN.
VERSUS CRACK DEPTH IN - - .vor ~ m.
KEYWAY VICINITY OF DISK #4 AT RATED SPEED 1E81.203 I
K g, g Kg g T) (N/mm2)
(KalG.) (Kal)(N/mm
-- 300- -150 ****8--1000 l
RNSION I
////tt Tt .. . ,,
O : /
- b
~
,'g[ stress W C 200--100 s, stress intensity K, d , , , , , , , \-
e N 500 N-
' N ~ ' ' ~~~-.. .
seen.e .
~~~-~~~... ,_
l 100- -50 l
sees.e .
I l
2.0 3.0 4.0 (in.)
1'.0
,, ;,'- g ;,-
.,,,, -(,,,, .-
0--0 ,;, ,,
Crack Depth a 486.0 547.0 900.0
- 3. .a.
j!
d Eb
- 'EG
.o s ss E5
$Ta 33; IIl Nuclear LP Turbine Disk-Type Rotors:
5 g"A Comanche Peak and 3
2 $3:g Is Grand Gulf-z as, i3 r,)
- El 25-N 819
!!!$i
?
STRESS AND STRESS INTENSITY ALLS ==CHALMEmes
- = = = v =r= == =
VERSUS CRACK DEPTH IN KEYWAY VICINITY OF DISK #5 AT RATED SPEED 1E81.204 S -- - - - - - - - - - _ - . - ____ ., _
'" ' ~ ' '
K Kis 6 l
(Kel ) (Ksi)
- I. I * *'I .
300 -150 wese.e . .1000 f
/w REVISION w ""*-
7 0
b 's 's,
\
/ stress 4 Stress Intensity Kg C 200--100
's, d 's, eees.e .
t 500
~~ ' - % -- -
f, ..._~~~~...
seee.e .
100--50 j
i I sees.e .
3;0 4;0 (in.)
1.0 2;0
- o. .o ..e
.. L;. b;- s,,,,, s-(mm) f s.e . 'so.e j Crack Depth a l
576.0 585.0 900.0 i
~
1 3.1
! 25 5 4
- ajj d Bh ild Nuclear LP Turbine Ea $3h Disk Type Rotors
a g g&& Comanche Peak and
, g 3gg o j at Grand Gulf 1
E E j na e..
- s 2sj.
b Eb SI$
- e.d s 5 Ea<zi<
g . .
l STRESS AND STRESS INTENSITY ALLao-CHALMunne
, == = v m -
VERSUS CRACK DEPTH IN KEYWAY VICINITY OF DISK #1 AT 20% OVERSPEED 1E81.205 j
x g K i, d
- I. ( **
(Kal .) (Kal) I 300--150 woes.e --1000 REVISION 7'g
/v/z/ W I
o
,ee..e .
g\ / sire n d \ Stress Intensity Kg g
- - - -- 200--100 d , , , . . , . \s t '%. _
-500 .._, ,_
.see.e .
- 100--50 soee.e .
1.0 2.0 3.0 4.0 (In.)
0--O 88 '
.,e. .. ,.. ,ee. . ,
.b.
i.e .e m..
(mm)
Crack Depth a 591.0 607.0 900.0 D
il a kb s.I y ES os 55 $!g II{ Nuclear LP Turbine 54% Disk-Type Rotors:
I $jj Comanche Peak and 2
z
%ag.af Grand Gulf i38
- 11 25)-
N8lk H hi STRESS AND STRESS INTENSITY AL. Lee-CM ALW as VERSUS CRACK DEPTH IN - a -v= r-. .~e KEYWAY VICINITY OF DISK #2 AT 20% OVERSPEED 1E81.206 r
Ng g "I : $
(Kal M ) (Kal) (N/mmT) (N/mmt) 300--150 wees.e - -1000 I
I REVISION -
/(/,/1<
g
'h seee.e .
- % Stress 6 \ J Stress intensity Kg
-- 200--100 d e.ee.. . -
" 500
'~~.. ' % .,,,,
~~--... ,
- f. seee.e .
100- -50 1
1 ee.e.e ..
4 -
.J b 3.0 4.0 (In.)
1.0 2.0 .'-
1 ' 'see.e 0O e.* ~
~ '.e .e~~ ~ 'ee .e ~ 'ee .e (mm) e.e ~ 'ee.e'
, Crack Depth a b
l' 780.0
'" 550.0 562.0 1
.i 15 d Eb l!
E.
y 'IEE ia sw w g l+ Nuclear LP Turbine Disk-Type Rotors:
" o E8 E E
E aj[II}f Comanche Peak and Grand Gulf 2
z ihl I ~ ,. a
- i32..
$$ l'j .
a a
'jg IX2j@i S
$3 a<zi< s
. $.)
.:w_
~- : ,m,,,c _ , ,
STRESS AND STRESS INTENSITY == a = var == =
',)59 VERSUS CRACK DEPT 111N KEYWAY VICINITY OF DISK #3
.i.; .. AT 20% OVERSPEED 1E81.20'T
,y o yn
, w, .n .z. ,,, ,;. ; ,, , z z
Kg g Ie d (Kal M.) (Ksi) (N/mmT) (N/mmt)
- 300- -150 -
seees.* . -1000 REVISION
/f//W4e eees.e _
\g Stress d
's b 's Stress Intensity Kg C
2M-100 -
\
s d
e sees.. _ N '~.,*
500 % ,
~-....._
sees.e .
- 10.#0 sees.e .
- i i i (' '}
0--0 e.* ' '
' ' e.e ' 'ee.e 'ee .e ~ 'see .e '
s'.e ' 'se .e' ' ' (mm)
Crack Depth a 574.0 592.0 480.0 11 5-
]!
o !!
- 5. "E y ES EJ
$2a 7aEli l E A t i:[: Nuclear LP Turbine AJ p$
3 g
8:} Disk. Type Rotors:
Comanche Peak and l oh j El Grand Gulf l E E3e m3 8 5526]=
N81$
! H 115 STRESS AND STRESS INTENSITY .m,..,,,,,
VERSUS CRACK DEPTH IN == a = = r==
KEYWAY VICINITY OF DISK #4 AT 20% OVERSPEED 1E81.208
Kg g I: I
' ** I. I **
(Kal G.) (Kst) I
- 300--150 ossee.e . -1000 REVISION /'s
- ~ Stress 6 b 200--100
\/
s s, Stress Intensity Kg C
\
d eese.. . g N
-500 N.
seee.e .
' ---..._~-.. ..
100--50 J see... .
f 1.0 2.0 3.0 4.0 (in.)
0--0 e.e . > .
.'9ee.e
~ ~
e.e ~ 'se .'e' ~ 'ne.e ~ 'ee .e ~'se.e (mm)
Crack Depth a 533.0 547.0 900.0 D
il a Ib l cd E.
s 'a l s EE !jEf l' 05 Nuclear LP Turbine l 4y 4"A Dic-Type Rotors:
Eo E: I Comanche Peak and l 2g $I2 Grand Gulf z a:.
i3226j 55 .
N8)$
25 !il STRESS AND STRESS INTENSITY VERSUS CRACK DEPTH IN 1"%7.1"". .
KEYWAY VICINITY OF DISK #5 AT 20% OVERSPEED 1E81.209
i Kg g (Kol .) (Kst) 300- -150 eesse.e .-1000 REVISION /'.
sees.e . Stress d g
V'g Stress Intensity Kg d \
e.ee.. . s 0 'N
\
-500 %'..' ' '---- . ,
sees.t .
100- -50 seee.e .
1.0 2.0 3.0 4.0 (In.)
0--0 88 --
i***----
e.o 'se.e- 'se . e- e s.* 8 8.8 '
(mm)
Crack Depth a 533.0 547.0 900.0 l.a z
d
's~ ' '.': e og IIE
$A $j Nuclear LP Turbine
,i g as Disk-Type Rotors:
Comanche Peak and 3
2 $jj 8
at Grand Gulf z a:.
i3 r, M 25)-
-0 ii!Xc5E
$.3s <zi<
STRESS AND STRESS INTENSITY VERSUS CRACK DEPTH IN T'O."r.""". .
KEYWAY VICINITY OF DISK #5 AT 20% OVERSPEED 1E81.209 ,
N .w.. . .~ n~_=~~ --
$ ,