Text

Evaluation of RTV Coatings for Post Insulators, Interim Rept
	ML20077E548
Person / Time
Site:	Pilgrim
Issue date:	01/31/1988
From:	Anzivino L, Howes D, Schneider H; GENERAL ELECTRIC CO.
To:	;
Shared Package
ML20077E545	List: BECO-91-074, Responds to NRC 910213 SER Request for Schedule for Implementing Station Blackout Equipment & Procedure Mods,Per 10CFR50.63(c)(4).Requests NRC Concurrence on 4 H Blackout Duration Based on Addl Info Contained in Encl; ML20077E548;
References
	NUDOCS 9106100479
	Download: ML20077E548 (7)
	v • d • e

_ _ _ _ _ _ _ _ _ _ _

ATTACllMENT A TO ENC 1.0SURE 2 I

EVALUATION CF RIV CJATIT.S TCF POST DiMJ7J'tS D.'nRIM RE,TRT EPRI Fesearch Project RP 2472-3 January 1988 Prepred at EPRI UIGH VCLT?GE TRANSMISS101 PISEARQ1 CRm3 P.O. Box 796 Lenox, Fbasachusetts 01240 by GE Princi pl Investigators:

Berran M. Schneider Lawrence D. Anzivino Douglas R. B wes Pre p red for Boston Edison Ccepny 800 Boylston Street Boston, Passachucette 02199 Project Panagert h.as Zazulak and Electric Power Research Institute 3412 Hillview Avenue Palo Alto, California 94303 EPRI Project Panager James F. Ball Electrical syste.-r Division 91061004'7o 710601 POR f4 DOC F' 05000273 p

PDR-

UmRIM REPORT JanuaG 1988 LVN.11ATICN OF }CV COATDUS FOR POST ISS;IldCRS H. P Schneider L. D. Anzivino D. P. Howes DCDCUJCETCM Plachovers have occurred on station post insulators in the 345 kV owite.hard at the PilgriJn generating station of Boston Edison OtrM in high htttidity conditions after onshore winds have deposited salt on the insulator surfaces.

Previous research conducted at the EPRI High Voltage Tranartirsion Research Center (LV3tC) in Lenox, Pascachusetts, has demonstrated that the performance of some types of AC substation insulators can be significantly irproved by coating the surf aces with Sylgard rocn temperature vulcanized silicone rubber (RTV) (1).

The previous tests, hcwever, were carried out on Italtioone bus support insulators and breaker st7 port coluenc.

No information was available on the degree of improvement which might be obtained on the types of in-sulators usLd r.t the Pilgrim station.

It was decided that artificial con-tamiration tests should be conducted on post insulators cf the type which are currently in use at Pilgrim over a range of contamination severity which is believed to be representative of service conditions.

EST PRCCEnmE Artificial contamiration tests were performed in the large fog cha-bet at the l

l EPRI High Voltage Trarst.incien Research Center in Lenox, Massachusetts.

This fog chamber is approximately cylindrical in shape with a height and dia:teter 1

(

of 24 = and a volume of 11,400 rd.

Clean fog is gencrated by bciling water in fcur large vats, three of which have a capacity cf 760 literc and contair. 80 kW of cicetrical beating elen; ente with the the fourth vat having one half cf that volume and heatire.

W.e vats are covered with camas cloths until the water is boiling, at which time the camas covers are removed and the test voltage is applied.

'Ihe contaminant applied to the insulators is a slurry containing water, sodium chloride of va:ying a:aounts to ae icve the require contamination severity, and 40 grams per liter of kaolin to represent the inert material or noncoluble dust which may be present in actual installations.

In.rder to contaminate the insulators coated with RIV, it was necessary to rub the surfacco with a wet cponge to reduce the hyd:cybebicity and cbtain a relatively uniform coat-ing. After the contaminant was applied and driod, the insulators coated with R'IV were allowed to rest for at leaat 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> in order to permit the hydrophobicity to restore itccif.

turire cach test, four full length 345 kV poet insulater asoc=blics were encr-gized simultaneously in the fog cha:ter.

Wo of these post insulators were manuf actured by Lapp Insulator and had a total leakage distance of 231 inches, while the other two were manufactured by H3K-Locke and had a total leakage distance of 307 inches.

Cne coltra of each type was coated with RIV and the others were uncoated.

A system of thin fuse wires was used to energize the insulators in parallel.

When one post flashed over, the system of fuse wires allcwed the test to con-tinue on the other inculators. 'Ibe voltage was held constant until fifteen minutes after the relative humidity in the chamber reached one hundred per-cent.

At this time, the voltage was increaced in stepc with five minutes duration at each level.

2

Ila w, t.a c ge t. levels of contaminatien severity were celected correcpording to eqaivalent salt deposit densities of C.08, 0.2, and 0.4 gcm2 The acttal level of conta:ninatien severity was deterr.ined by ca :pling several cheds of post insulators of the Sr.e type, e.g. Ls;p unoosted, etc.

TEST RESULTS AND PRELIMINARY CONCLUSICriS

'Ihe tect results are shown in Figure 1.

Unfortunately, it was not poscible to achieve the target levels of ESID in every test, as e.sy te seen in Figure 1 by ccr: paring the target and actual ESDD values.

Nevertheless, a good cccparison cf post insulator perfemance with and without R:V coatings was obtained. The data in Figure 1 indicate that the Lapp post insulators flash over at operat-ing voltage with GDD levels as low as 0.064 2:q/cm2, wherena the mK insulator flashes over at operating voltage with an ESDD of 0.15 mg/cm2 RN drcati-cally 1:: proves the perfor:.ance cf both types of insulators.

The flashover voltages for the coated mK insulator are substantially higher than those of the coated Lapp insulator.

None of the R:V coated insulators flashed over at operating voltage with ESDD levels as high as 0.68 rg/c:n2, l

REFERENCES (1.]

R. E. Carberry and B. M. Schneidar, " Evaluation of ICV Coating for Sta-tien Insulaters subjected to Coastal Conta:tiratien", Fa;er 88 WM 069-7 to be presented at the IEEE PG Winter &cting, New Ycrk, NY, February 1-5, 1988.

3 l

e e

e

.........._m,3.........-......,.....

i j

,i.

4

.4

.--.....~...

a 4

..L i

-~+;

I l

e

.- ~. --,

... +....

p.+.-...--,-,,.--

- l..

~

..-.-*~*.....;..

e

,u:

e' u y",. m

.ne*.

e s.

.,a..

-.... q:. -~

p :'.? * *.. ~, ~ * :i'3;_.~_."

is ' O I

= = - * * *

' =. n~**:W:: :.p.1,; 4;.L.';.*}n *...

-)..

' : r.d i *-' :

'~-~;

bt

^

l ;* :.. _ f 3. b e c*t2 101JB1 k X A )(

= _

_ 6:' ;- G

~ n

. Wi. 42.'.--

$.rV l l'.i.

. =...= =. - tr_ 5.. _L 5 = 5 =O. n_h. W.-

n.?.....

g si to C.

."q) set te

~ C

.:.-....._._..-.j.....

~

r

+

{

j.,..

..~..

. _......,.,. _,.....m..,...........

...-.,.4.~-_.--,p

.4

si

.... ~ _,.

9

. l 7."g g, O

E

...,l._.

.'.1......

..y

...o.

] ],=

g

., -._i 1

.. i..

.,n..-.L,..

.i i..

.p

) 1

.l

},.__ _ _ _

V..- q,~...

.v.,.....

. l..

. a s

.... e.....

j w.

y m._.. m. _p. p.....

..%...+--..

..~L..

.m.-..........

....l..{..r.,...... ~.

.i

~..-......+.+4

.pe.,..

L...

.i J

-+-+,~.e.......*.,+~e-

.1 e

w.+.

w 4.O,.3

...e. 4%.

4

.L t

i.

..4.

)%-

r.

c

.4 4

e

'C i.

.4

'.,. I.....

a

.+c...- w..- w w +...l.6. b

,,n ~,., e. e!.,...a... ;.

m,e 3.

..i... H,.g e

4 7.

-h m.+.

.g 4

.i 4

I, -

' q w+ W,:-..

,.,.4;

+w.

6.-t...

,,1.I, d, ! i.;: ',i 4

49e..

y'

.r..

,.9.,.

+.

p.+,4.+.

h L.4,1,.,. l.. i f. L,..,,j i q.d.+ M i i.,.

T l-

~. t.. 7

...p..

- t**'"* **' b f M** * N I ~ ' 'T~ t-*,)=7=+g ~'

.m*-*.

.gy*

6 **M **'

,+

.(

m,. 4- & ++- h,,

,++++ g

m 6 6+7 t'

- ? ? *+ f 4 f **-*I * *' ' ' * *4 "

' *- - - * *' M '*-

=

4 b -*

60

' l...

r

+t*'--*

'4-**:

I 3

a* w.

" 4 i

. i I'~ t.N..._i

i

,,i_

i

=e

+.t

_.,...*i,-...

.+i..T

. *I m.

9

.*, i i

Mw M gA, i..

1 i

iii i-i

.4 lg

-+ i-

+.. <i... '

6 r

k.. i..i..,i.

,., g e

,. ii,i ii.6; 1

i't;ii,: ;;

,, t J i.q o 1

'.t e

i 4 I

is

' L :.,

e.' H 4

. ;+ *

^ -

m+

i i. -..

i i

=

..,9..+

J -.,..

. +

>b N

- i#

l.

n

. i 1l t

. i '. i i e i 1 is

-r i.i.iil-g i

+

3 4,.F.1...m,-. r m.i i

5 i

i et*

i

.'. i i

i

.i.M. h,,' i :

, 'ii i:4 )W.!!'ll.

! elli il.1 l

, l I

be i

r: i i

.t

..t.t E.

n

.I t

l

-e w.+

r

~ l l i l'! li ti f,,.

X t

?. D M $ 7 tj

[*MM'7 I'.((.

7

.S E

7.....~, 'I E

.I, I I E j.6

! { iiII

.ii l pI

,,.. _i r

= c lt'

{f!J ill'--- l!;I!!<.I-l I ! ll I si !l' -.!ll.!

l*Ii!l l

ti l

., +,.. *..',.L.,

ll

'il j;,f 2 d

.v

+

L-.

"J

,. + _.. +

lI'

'l !!

l !!C ilI.i t - l l' l'l'l!.l!l I i!If,!ll "k ! !!

! ! : 'g '

3 6

i i t.o 4

e

.m

, = _

...;.~. :_. _._.m, i :*.22.....,. _.,.n. t,,.;t

+

z_

na

.-,,.!..r....,.,..

__,r

s. inn.

.4 L.- e.

. u 1...].,...,,.

C...}

~.4 OC tn s

s.

4.-.~.4..,...

3c-e.

k.

c.,

---m__

m....

.~t*'..__

4

~.4.e.-

3

..,g

.s f1

.. i..

e

'.a

.e-.

....,,.....,,. l...,..,..i_

.S.,.

y

%.. t _pT$ p.

~. ~

w.. _.r.

~ _

.;.J.,.;,,,.,.~

.,w 6*

y'",-. 2.,.*..).. g ". ;,'., *.: *g.~ g, %.~ * ;+: :~.:.C,c

1

",_ Q7.g n

,-U ~

. ;_ 4..q. -- M.;...

...:^.=....._"""*v

P -*'*','} ~. *. *. 3 :

=..-..;.~,.'. = _ _,_

p

.u_

.u.

C. " -

- T-- -...l

- ;.. -+.:- + -*:

r

-* * ~ r! Tn.y ' =,.,.. =- -. *.. t d *t 3 *.*. !. ;c---* :-.;*dpy*=; :+;y

~

._...._ g *... p* m___.

- - - r. /"

t.

=1

+

A

!. R

,sC

.+e...,.,_._._.y._...._....,e,.

_ _. __..,::....m,_.,,....m,-J..

6 us. o

,... ~.

. -. -.. +..

..j

.g

. i.

_t,,9,,...,

a..

e-...

t.

6 4

en -

p.

.4f.l..-.....

.+.

...'p..,.i., l p...,...

w.

g_--.~.

.:_...4 e.

.t

.a i

._..._m,

, q-

-- M

- - -W A

-.h.-e

.e..egeh@e.m.*.1Q.=.Gp

.J. W m

.Y W.N

^

.M.6 M. h m.

4 r

N N' O

- .~a

.e.e.$

>..mp e.s.t

_y

+

-.e..

e. 3

=.3e p*-*

4

+ +.

.. =.

N.--'*.*..O

-+

,,..w

. +. -.

+

-e._

. +. -

+.g.

w. e.e u.-.*=e...;....

9.-

.e.e e ee + i.,.

h_.e

~.;

,...e 3.e -.. -

.....4a.,

g

+-

+-.+6=**

-m..

e-

..~

..~ -.

3---.m<

+. -

.-c.

+ [,'

..6.-.--.*--

. ^

o o

e e

1-s, 4

o e

N

.3 e,

,-r N,,

f*

C

,D 4

rs se e.

~

n

+

('.~;' M /.* MINV l

1 a.

IlI1 1l\\,

j

,l 1lfI (ll1 Ilj/lli liil

)

IjI l1lilll ll t

t_

t n

n n

e e

e n

m n

r r

e e

e v

v v

o V

V o

V V

o V

V r

k k

r k

k r

k k

p 4

7 p

7 G

p 3

9 n

4 9

m 2

4 n

6 1

r r

I 1

3 I

1 I

g g

g v

v v

A A

A e

e e

g g

g a

a a

t t

t l

l l

o o

o V

V V

NN NN NN NN NN NN r

r r

e eO 0 e

SO QG e

00 GG v

v v

o o

o h

VV VV h

VV VV s

kk kk s

kk kk a

26 29 a

96 08 a

25 87 l

24 59 l

18 34 l

1 5 22 S~

G T

N F

23 23 F

22 23 F

22 23 L

I U

T S

S g

q g

v v

v Y

E

'f R

R T

A A

M T

G 2

M S

O,'a 2

m U

E F

i a

c S

T c

r N

/

c

/

I A

g

/

g 22 22 R

E 22 22 g

22 22 m

mm mm n

I P

L D

aa un a

D mm mm D

cc cc

r r :

r E

C 8

D cc cc D

cc cc D

//

0 S

//

2 S

//

4 S

jg gg n

E gg gg E

u 'n aa E

Jg gg r r r

0 rn on 3

nn na r r 63 88

=

g 89 70

=

g 97 89

=

g 34 25 v

00 01 v

11 11 v

l A

A l

e e

e v

v v

e e

e L

L L

D D

S p

E p

K p

K E

p K

I a

C a

G a

G t

L N

t L

N t

L N

e e

e g

d d

g d

d g

d d

r pe e

a pt Kt a

pt Kt a

pt Rt T

aa Ga T

aa Ga Lo No Lo No Lo No r

C C

r C

C r

c C

o d

d o

d d

o d

d ed ed 3

t ed ed ed ed 2_

t 1_

t a

t r t r a

t r t r t.

t r t n 1

aa aa e

l.

aa aa aa aa e_

l u

oy og u

og oq I_

u oq oy f

l i

s_

cl cl 5

s cl cl s

cl cl l

t ny ny a

n ny ny a

o ny ny i

i s

S US T

l US US i

iS US T

J t

T I

l o

'124i:

i

_=. _

IPRI T E S T RE S "L_T_.S CLEAN FOG TESTING "TASHCVERS AT OPERAT!NG VOLTAGE 1.

TARGET ESOD LEVEL

.08 mg/cm n

Uncoated Lapp -- 3 of 8 tested Sylgard Coated Lapp -- N0ne Uncoated NGK None Sylgard Coated --None 2

2.

_ TARGET ESDD LEVEL =

.2 mg/cm Uncoated Lapp -- 2 of 6 tested Sylgard Ccated Lapp -- None Unconted NGK -- 1 of 6 tested Sylgard Coated NGK --- None 3.

_ TARGET ESDD LEVIL =

.4 mg/cm Uncor: d Lapp -- 4 of 5 tested sylgau d Coated Lapp -- None Uncoated NGK - None Sylgard Coated Lapp --- None i

ML20077E548

Text

Navigation menu

Search