ML20118A131

Staff Exhibit S-67,consisting of Re Mlea Project 90009 Involving Thermal Behavior of T-95 & Scotch 33

ML20118A131
Person / Time
Site:	Farley
Issue date:	05/18/1992
From:	Crane C MAIN LINE ENGINEERING ASSOCIATES
To:
References
CIVP-S-067, CIVP-S-67, NUDOCS 9208030091
Download: ML20118A131 (15)

Text

- - - - --

S-67 surr an. m '

2 a us,/ 3sl-ervp 6/w /9z-b7 -

Main Line Engineering Associates aup uaknL ,

2 967 E. Swedesford Road A Exion.eenns>ivaniai934i v2 3 -2 m3 :oi (215)689-9525 FAX (215) 889-9419 g,nne,,

Tneooore; oeica2d Tud c4Elt S'4 Serial No 90-159 cyra; crane.e E DvLht im Ot "'d July 12' 1990 Freceric k w. Vosbur). P E. RN" Mr. Mark Spinelli Electrical Engineering Arkansas Power and Light Co.

TCBY Tower (TCBYT 17)

Broadway and Capitol Little Rock, Arkansas 72201 -

Subject:

MLEA Project 90009, Thermal Behavior of T-95 and Scotch 33

Dear Mr. Spinelli,

Enclosed for your information and use is M1 SA Report 90009-0013, Technical Evaluation d Qanite T-95 Taped Splices With ScJ.:h 33 Jacketing Tape and Unjacketed, Thermal Agnig Behasior at an Oven Temperature of 310*F. The enclosed report contains the results of an investigation into the physical and thermal properties of Okonite T 95 insulating tape and Scotch 33+ vinyl electrical tape to determine the reason (s) for the unusual behavior of these materials during approximately 40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> at 310*F. Copies of References 1 through 5 of Report 90009-001-3 are available at ANO. Copies of Refererces 6 through 9 are enclosed v.ith the report.

It it, interesting to note that the ph,.sical properties and thermal behavior of both T-9i and Scotch 33+ at elevated temperatures (i.e. above 105'C) are not contained in any of the published literature available to the purchaser of the products. In fact the information obtained by MLEA is not available in any published literature from the manufacturers, only in interrial laboratory reports.

With the informetion contained in the enclosed report it is considered that it is possible to establish thermal aging parameters for Scotch 33+ jacketed T-95 tape which can be used to preage specimens for LOCA/HELB Simulation testing. The.se parameters will be the subject of separate correspondence. However,it is MLEA's judgement that a successful test of unjacketed T-95 (viz. Specimen 14) cannot be performed.

Should you have and gestions or comments on the enclosed report, please contact us at your earliest convenience.

Sincerely,

' A. D -

C J. Cran

(/Profect Managc Manager of Engineering 9208030091 9PO518 PDR ADOCK 06000348 O PDR "r

CC:

A. J. Wrape i;; 1./JJ L)

T. Ott (AP&L)

K. J. lepson (ICE)

Document I.D. 90009 001-3 Date: July 12,1990 l

i i

TECHNICAL EVALUATION OF THERMAL AGING TESTING OF OKONITE T-95 TAPED SPLICES ._

l BOTH UNJACKETED AND WITH SCOTCH 33 JACKETING TAPE AT AN OVEN TEMPERATURE OF 310"F

Prepared by

Main Line Engineenng Associates 967 E. Swedesford Road Exton, PA 19431 Prepared for: Arkansas Power and Ught Co.

. TCBY Tower Broadway and Capitol Little Rock, Arkansas Meu /mh Prepared by(:J/ . Mupp!Iy, P;6je.tsianager Date: 7//A/fd Reviewed by: I Date: 7//t/80 t ' C. J/ Crane, Manager of Engineering

~ ..

j.

I 1r.troductigm During the thermal aging (at 310*F) portion of an en.ironmental qualification test of various splices using Okonite T 95 insulating tape with Okonite No.35 jacketing, Okonite T-95 insulating tape und Scotch 33+ jackuing tape, and Okonite T 95 insulating tape with no jacketing tape, it was discovered that, after 40+ hours of thermal aging, the unjacketed splice and the Scotch 33+ jacketed splices showed e idence of melting and Dow of the T-95 material. Reference 1 contains a detailed description of the condition of the splices and an evaluation of the test conditions, equipment and instrumentation.

Since there was no indication of any anorualous behavior of T-95 insulating tape in the Okonite Product Literature or in the Okonite qualification test reports for the T-95, MLEA contacted Okonite engineering personnel to determine the possible cause of the observed behavior. References 2,3, and 4 contain the substance of telephone conversations terween MLEA perso:mel and Okonite personnel. Reference 5 is a letter from Okonite which discussn the characteristics of the T-95 material. The information contained in references 2 through 5 is summarized below:

. T-95 tape is an uncured (unvulcanized) EPDM material Because T-95 is uncured, it is basically a highly viscous liquid at room temperature At elevated temperatures, T 95 will flow unless restrained by a suitable covering (viz. No. 35 jacketing tape)

. The tendency to flow is a function of both temperature and load (force applied to the tape)

Tne volumetric coefficient of expansion is between IE-6 in 3/in3 /*C and SE-6 in 2/in3 /* C Based on the information ccatained in references 2 through 5, MLEA has concluded the following

)

. At some tirre between 24 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> of testing and 40+ hours of testing, the i T-95 material expanded to the point where the ultitr?*e strength of the Scotch 33+ jacket was exceeded.

. At that time the Scotch 33+ sple, and the fluid T 95 oozed out through the split and flowed onto adjacent s trfaces.

I l

. At some time between 24-30 hours of testing and 40+ hours of testing, the unjacketed splice started to flow and, having no restraint, dripped under the force of gravity to the bottorn of the test oven.

This report contains the data obtained on tne physical and thermal properties of both Okonite T-95 tape and Scotch 3. & tape. Using these properties a technical evaluation of T-95 tape jacketed with Scotch 33+ is performed which establishes the root cause of the anomaious behavior des:ribed in Reference 1.

II Properties of T-95 fEPDM) Material:

In order to perform an analysis of how the T-95 tape behaves, it is necessary to determine various physical properties. The properties of Nordel(the source material for EPDM) and the source of the properties are contained in the following table.

Empnj Valur Referenn Thermal Conductivity (k) 576E-6 Cal /(sec)(cm)*C' Ref. 5 Heat Capacity 0.56 BTU /lb/*F Ref. 6 Specific Gravity 0.86 Ref. 7 Coeff. of Expansion 1.0E-6 to 5.0E-6 in/in/*F Ref. 5

• 576E-6 Cal /(sec)(cm)'C = 0.1393 BTU /(Sr)(ft)'F There i3 no available data on the properties of uncured (unvulcanized) EPDM material. The information obtained from DuPont in Reference 6 is based on a typical cured material. In Reference 6, DuPont stated that there was no known '

application for uncured material. The specific gravity obtained in. Reference 7 is also.-

for a typical cured EPDM, no information on uncured was identified. The coefficient of expansion identified in Reference 5 is a volumetric coefficient.

Ill L2retties of Scotch 33+ Tape:

In order to determine the behavior of Scotch 33+ jacketing tape applied ove Okonite T 95 tape it is necessary to establish the proper'ies of the Scotch 33+ vinyl tape. Reference 8 is the 3M product information bulletin for Scotch 33+. From this builetin the foi:cwing properties are determined.

Property Value Reference Elot.gation (@72* F) 250Fc Ref. 8 3

t

- e .- - - - - - < -- - - - - - . - - - - - - - - - - - - - - - . - - - - - . _ - - - -- - ..- - . , - -

-)

-)

Property VCue Rererence q i

Tensue Strength (@72*F) 3000 psi . Ref. 8 l Break Strength 16 lbs/in Ref. 8 -

l Aging @ 113*C 60 days Ref. 8 Reference 9 contains information provided by 3M on the elesated temperatu:e behavior of Scotch 33+. BrieDy the behavicr of the Scotch 33+ tape at a reta},erature of approximately 300*F is as follows:

1. Tr.e plasticizers in the tape and adhesise volatilize in a relatively short time and the tape bc.comes brittle.

2. The Scotch 33+ tape will attempt to shrink to its original unstretched length. i IV Technical Evaluation:

From the information presented in Sections II and III above, it is apparent that as-ambient temperature of a taped splice is increased above 105'C (221*F) the T-95

-insulating tape expands and becomes less viscous while the Scotch 33+ sofiens permitting the T-95 to expand. As the temperature is increased to 150*C (302*F),

the T-95 insulating tape continues to expand and become more fluid, but the Scotch- ,

33+ start; to 3hrink slo'vly and starts to become brittic. After a period of tire.e (24hr< t <40 hrs) the Scotch 33+ tape splits and the T-95 tape oozes out of the

plits in the Scotch 33+.

The behavior of the splices made using T-95 insulating tape voth Scotch 33+

jac;ketag tape during the thermal aging test at 310* F is consistent w;th the properties of the materials based on the information supplied by Okonite in Reference 5 and by 3M in Reference 9. However, the data supplied in References 5 and 9 are un; ublished and not readily available to the purchaser of the produ V Con, jusion:

Baseu on the irformation supplied in References 5, 8, and 9, it appears that the upper temperature limit for aging of splices made with T-95 insulating tape- and Scotch 33+ jacketing tape is 113*C (235.4*F).

7 4

a

!i VI

References:

1. Report of Trip dated June 20,1990, ANO Tape Splice Test, Investigation of Reponed Anomaly

2. hiemorandum to File dated June 19,1990, Informatior. Receiw I from Okonite Regarding Thermal Properties of Okonite T 95 Splicing Tape

3. Memorandum to File dated June 21,1990, Information on T-95 Tape from Okonite

4. Okonite Biilletin 22.9.0, The Fundamentals of Splicing and Terminating Electrical Cables,1981 ._

5. Okonite Letter from J. S. Lasky to J. A. Murphy (MLEA) dated June 23,1990

6. Memorandum to File dated Ju!f 9,1990, Thermal Properties of Nordel (EPDM)

7. H andbook of Plastics and Elastomers, Charles A. Harper, Editor in Chief, McGraw Hill, Table 35 S. 3M Product Data, Scotch 33+ Vinyl Plastic Electrical Tape E-MTD33-5(3110)R

9. Memorandum :a File dated July 11. 1990, Elevated Temperature Behavior of Scotch 33 Insulating Tape 4

5

REFERENCE 6 MEMORANDUM To: File M"

Frornp. A. Murphy Date: July 9,1990 Subj: Tnermal Properties of Nordel (EPDM)

On FrMay, July 6,1990, I called :he DuPont techn; cal information senice center to request info.mnation on the thermal conductivity aad heat capaa:y of Nordel (the source material for EPDM products). I received a recorded message saying that the technicalinformation center was closed, to leave my name, telephone number, and information re4uested, and they would call back on Mondey morning.

On Moaday July 9,1990 The DuPont technicJ information senice returned my call and provided the following informatic.n:

Thermal conductivity of a typical Nordel product = 576E e Cal /(sec)(cm2 )('C/cm)

Heat Capacity = 0.56 Cal /gm*C or BTU /lb* F I asked if there was any information on uncured Nordel anc was told that D"Pont was unaware of any application for uncured material and therefu*e had no data on uncured material. I was told that i , significant ditference in thermal conductivity cr heat capacity would be expected, but that the fillers used in compounding the cured mate-ial tended to increase the :hermal conducti,ity and reduce the heat capacity because the fillers usually contained metal oxides, metal carboaates and metal silicates.

e ts

-I I

REFERENCE- 7 Mar as P,,, emes .t a.. tome,meonen ed  ;

Styren,-isopreE Chloro- styrene. and Epi;blorobydrin Ethylene eulfonated styrene.bute. .

homopolyroer propylene polytthylene Dvorocarbon - Propylcae dieno.styttne -

Property and copolymer Fluorosilicone (EPDM? (Hypalon) elastomers oxides block polymers Physical properties:

Specife gravity... 1.32-1.49 1.. S 86 1.11-1.26 1,4-1.95 1. 'J2 . 0.94-1.35 Therrnal conductivity.

Stu /(h)(ft')('F/1.,. . . C.13 0.065 0.13 .. .. 0.087-CoefEcant of thermal es pansion.1(r$/*F. , ..... 45 .... 27 s.s ..... .. 7.5

1. .t esistance. . Fair Poor Poor- Good Eaeellent Poct Poor Colorabuity. . . Good ) Good Emeeuent Escellent Good Good Good

' Meeha+ cal properties: ,

P vdness (Shore A) . . . . . . . 3 %95 40-70 30-90 45-95 65-90 40-80 35-90 Tensue strer.gth,1.000lb/in)

Pure gum.. .. ..... I <1 4 <3 >l 0.7-4.5 Reinforced. . 2-3 <2 0 6-3.2 1.5-2.5- 1.5-3 >2 Dongation. S'e -

Reinforced 3?O-350 204400 200-600 250-500 100 @ 500-670 350-1,350 Resuie nce . . . Poor te enceuent Good to fair Good Good Fair Very good Good 4

Cempression set resatance . Very good Good Fair to good Good to emeellent Fair Hysteresa renstance - Good ...... Good Good Good Good Very good Tiencr ac king resistance . Very good Good Good Good - Good Very good Good Slow rate. Very pod Good Good Good Good Very good Good Fast rate . . Good Good Good Good Good Good Tear strength. . C,ood Fair Poor to fair Fair to good Poor to fair Exceuent Fair to good Abrss;on resistar ce . Fur to good Poor Good Exceuent Good Good Good Deetrical properties Dalectrie strengn. Fair Good Excellent Exa!!ent Good Good Deetrical insulation . Fair Good Very good Gord Fair to good Good ThermW properties Servlee temp. 'F;

-~ Min for continuous use . - 15 to - 60 - 90 -60 - 43 - 10 - 80 - 60 to - 80 Mas for continuous use- 300 400 < 350 < 325 <500 < 250 150 Low-temp sta!!enug. 'T - - 15 to - 60 < -100 - 20 to - 60 - 30 to - 50 20 to -30 - 60 to - 80 a

t.ew

' Corros'on f e5@'ance . ' '

Weather Eteeliet t ExceUent EmeeUent Ezeellent EzeeUent Very good Fair Oxidation Very s w d - Exceuent Ezeeuent Eseeuent Outstanding Very good Good

- Otone. Good to exceUeni Es ceuent Emeeuent Eseeuent- Emeellent Very good ' Fair Radiat:en .... .. Good Ezeeuent - Fair to good Fair to good .... .. Pocr

- Water Good Exceuent Good to excel:ent Good Good Ezeeuent Good Acids. . Good Very good Good to exceUent Excellent Good to exceuent Good Good to e sceUent AlkMies . Good Very good Good to escenent ExceUeat Poor to good Very good Good

' to emeeuent Aliphatic hydrocarbons Enceuent Eacellent Poor Fair ExceDent Poor to fair Poor

- Aromatie hydrocarbons. Very sued EsceUent Fair Poor to fair Eseeuent Poor to fair Poor Halogensted hydrocarbons Gwd Poor Poor to fair Good Poor Poor-Alcohol . . Good Good Very good ExceUent Good Synthetic lubricasts (diester). ..., Fair to good ExceUent Poor te fair Poor Fair to good Fair to good Poor:

Hydraube cu2ds:

SUiestes Very red ExceUect Fair to good Good Good-Phosphates . Poor to fair Emeellent Good to ezeeDent Poor to fair Poor 1*ses . . Diaphragms. Parta requir- Lettrical in. Fles chemical O rings brak. Electrical in. Thermoplastic '

pri.nt rolls. Ing resistance sulating and and petrotram sesla. abaft sulation, grades: molded belts. oil seals, to lugh-temp jacket.ng; tute and hoee. seals. gasketa. molded mech- mechanical ~

molded mech- solve.ta or footwear. rors. tank lin. hoes and anical goods a4% pack +

anical goods; oils; seals, sponge, proofed i'2gs; b.igN ducting. con- aging. 4 porta ga.sheta, bone ga.ske's. O fabrics. temp belta: nectors. dw equipment.

for patroleum rings autome jee srire and phrana, disposable hanGng ; low, weather strip. cabie: shoe carburetor pharmaceutical temp parts ping. hose. . oles and oeedle tipe, item s.

belts. auto, heets; Soor. Eined valves, Solution g-ades; appCu ce ing: building pac kin gs, adhesives, parm parts products; roll coverings coatings requires out- estruded and calhng.

etanding o.one molded paru

• sealants and heat resistanee f

_ _ - _ _ _ _ _ _ _ _ _ - _ _ _ _ . _ _ _ _ _ _ _ _ . _ _ _ _ - - - -- .. .r- - -- . - v

, REFERENCE 8 M%nr*

l.

Product Datt be I r . , Q@

-- C J Scotch' 33 + EdL,_ JuMM-hst 0[~-

Vinyl Plastic ElectricalTap g i

2. Applications e d calPrcp m

1. Product Der:ription

- Pnmary electricalinsulatfoe After Standard Scotch Brand 33 + E'ectncal Tape is (especieltyIn moisture and 10,000 volts a conformable 7 mil thick vinyl ptastic sotvent vapnr areas) for allwire gh79 insulat:ng tape which can be applied and cable spilces up to 600 volta I After Humidity 90% of under all teather conditions and is and 105'C (220*F).

designed to periomiin a continuo : . Conditioning 4tandard con-temperature envitanment up to - Forms a protecttva jtoket (axcel, 1 ASTM D 1000 79 tioning value lent abrasbn resistance for high.

10S*C (220*F). It has excefient Insulaton Res' stance i 1x10' vettage cabW sp0ces and ter- Megehms es, a id c crk a dvarying mhan na)- ASTM D 1000-79 weatner condinens Oncluding Eveftrture wire sp!!ces up to 1000 sunlight). 33 - . with its combinam- Chemical Proper'ies volts.

of mem0fy (oiastic:ty), adhesion Water Absorpton

,- For wke and cabie hametsin9-charactonstics and 7 mi! thickness ASTM O 570 63 1*.

provices moisture. tight electrve and mechanical protection +: . rmnimum Resistance to Uttraviolgt bu*. Scotch 33 + pt ses ,inder- 3. Data Light wnters' Laboratcry tests to p!astic Paas W. See Section 5 erectr. cal tape. Typical Proporties Electrotytic Ccerosion 3M. See See:1on 5 1.3 ratio Physical Properties O Tape Features are: Restab ito Alkaks Exceitent Nerma! Temperature

• "' - Po!yvinyl chiortce (PVC) backing. 80*C

- Pressure sens,t:ve, rubber-based aW - % Those are typica rape'rtles knd 3M - See Secten S 105'C *

• a c e n e. Black e],7e ,,

9*P'C Color

- Ficxibyty and ac5esion at O'F.

allowing conformance to a!mest Thicxness ASTM D 1000-79 7 mits any subsrate.

- Memory cf the tape a9cws it to Achesion *o Steef 4. Specific 8tlCOS hold tght:y,and provide pressure ASTM D-1000-79 72* F 21 cz An. Product to uncerlying substrate wrthout 50 c: in.

C*F Qe plast tape k W on @-

s ipping or f!aggmg-Adhesbn to B ickJng viny! chloride (FYC)IMor fs

-- HigNy resistant to physical copolymers and has k rubber based.

abuse, chemicai attack and ASTM D 1000 79 72*F 20 czJin. pressure-senaltive adhastve The u'traviolet Ught. 50ozAn.

0*F tapa must be appicable at tempera-

- Cc npafble with a!! so!io dielectne tures ranging from 0"F through 100*F B eaking Strength catteinsulations ASTM D *000-79 withcart % of phyh or eW

- Usable ter enher tr' door of 72 16 lbsdin. properties.The tape must not crack.

outccer appHeatons. 1 sec. spt!t. sHp or flag when amosed to Flammability UL various envirW,ien4 (Indoct ur

- Corrcattle witn rubcer and Accelerated Aging outdoor).The tape r$ust also be synthetic soDcing compounds as 80 % compat!ble with all syntMtic cable we:1 as epoxy and potyurethane MILI7798 A insulations as well as cable spacing resins

- Meets U/L requirements for BC"C. y ASTM D-1000-79 h 30*C compounds Engineering /Arphitectural

- Meets proposed 105'C (220*F)

Utt; mate songason Speelfications ,

ratmg requirements.'

ASTM D 1000-79 Primary electricallrwuf stion branch

- Mamtams Ngnacitage pretect'en 72*F 2SO%

despite h:gn.mnisture concentm. 50 % wiringinwetordrytpcations. Ali O'F sphs for 600 m tire rated 105'C tiens.

wao o.c %c n wL t maA (220*F) and bekw $411 to intuiata=

se ier.me ren T m s crwac:eeuw ansTenoc.- ,

l

..~. ...,. -- ~ . ~ . . . _ . , . , _

t

3. For each spfke,use tw 12 inch with a minimum of two half fapped (304,8 mm) lengths of insufeted j conductors and strip a 0 inch layers of Scotch 33 + Vinyt Plastic m (50,80 mm)lengtn of iruutetion f ElectricalTape. A!!connvetors havina irregular surfacos shaJt be -

from one end of each. onnect the two bared conduct rs paddM witn Scotchfil Brand Putty oi I together by means of . Inline Scotch Brand 23 Tape prior to 6 en,s spilcedeee insulating with Scotu 33 t E!xtrical '

Jom (Westemunion)The ends of the i# Ec wm Figure 3 below),

Tape, e -

mm ctmhh criraOM Forms a nrotective jacket for High- }.o'p; t cown with p(ters to ea d sham vertage Cable Sphces and Termma. projectons.

DOUS-

@M ..

~ f Yg N Allrubber and thermeptasticin-sutated high voltage cable splices eoi* rcI we C ioco

(

fgpg g,gn ,. wMD'~ ,

and terminations shall be ovar- g wrappec with at 8. *st two be!f lappec FM 9

layers of Scotch L+ Vinyt P%stic spn1

~'

ElectricalTapo. NOTE: Lower force In required with Firtwo WWng: All sp0ces up to 1000 3b Tape, as shown,to obtaininitial A Whinupporting awqht of elongation. Some elongation (10 to 21/2 pource, a strtp of tape of vehs and 105'C (220'F) or less, 15%)is required to obtaan confo , suitable longinis to 60 held requi nng insulation shajt ce over- ance. Force required for 33 + Tape is vertically with the upppr end of wrapped with a minimum of two ha:f-la: ped layers of Sectch 33 + Vinyi at r. level wh6ch allows easier taping the tape held against ne and thus provides maximum protec, insulated wire just a4acentto Plastic E!ectricalTape ton in the shortest possible time, the tpfce,inttlally,tN major aes etne spree we

5. CharactenStics and approwmatWy homontWM and High Temperature the tape is caused to wrap tt Test Data Through specialized compounding wire and splice by ro$tting th and uruoue processing techniques a spree aboutits malos axia.The The Adcee + of 33

• more temperature stable plastic tape major axis of the sp!nosis tipped low Temperature has been produced. 33 + Tape from the horiaontal 30 that

- utperforms other plastic tape when tumof thetapeisto everiapthe A plane tape to be easily handied at tesied as shown in following para-any temperature, must have good

• precedingtumbyonkhalf the grapns, Egosure to Heat width c8 the tape. Aftpr the a:engation and adhesten. Scotch g 33 - has good elongation and very A maximum temperature rating of hign achesion even at temperatures 80'C can be given to a plastic tape, as low as O'F. 33 + Tape will adhete This temperature rating ls in accord- gte gm,a ave been ance wtth Underwnters, Laboratodes complet wrapped, a second to irregule surf aces and to most suostrates uncer very extreme spe atbn. 3M has ra6ed the test wrappmg to be *Mrty ,

temperature to simulate a 105 a;pued,with direccon of temce atwes. of tape rating. 33 + Tape was designed to aWance of the turm meet the stringent requirements of reversed from that cf the first "l -

wrapping. Fina!$ a lhlrd

7) N

' q'

• this tast~

Ing of tapela fo be 5e ,,~jj wr*

sm fey appned wie the Exposure to Heat directionof advancunppostte to

w. i A thermoplasticinculating tape

, 1. thatof the secoru!cappog.

3 e. sha!!not crack when flexed, or Thus six thicxnesste of tape will j

u.

f /

otherwise ce nove sery af-fected,aher being su ected to result at each pointalong tne

', I splice.

• j- / M" a temperaMr e of 11 (235*F)

M The (neu(ated splic(4 are then

~

ict 60iays to be piacedin an @en main-To determine whether a tape

1. * * " d , " " '*

• 2.

apus witn the requirements tained at 113'C (235'F). After 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />,two of the sofloes

{n the preceding paragraph,four employ'ng thermopostic F9ure 1 1 Arm-insulated spilces ars to be insulated T wire aos two of made wth Type T, Tw, THW, or those empioying ricoer in-Re.,om Temperature THWN wire and four with Type Secten 33 + E!ectrical Tape has eulated R wire are lo be re-R, RH. RW or RHW wire, es

^

been cesigned to be easny apphec by any worxman. At rocm tempera-described in the succeeding paragraph.The conductoris to moved from the een and subjected to f!exity as (

ture the tape can be efongated easi!y be No.12 AWG softd copper described below. I fanure occurs af*' 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />,the test white the force required to break the and the solic copper conductor tape has been fewe ed. This means of a Type R. RH, RHW, or RW shallbe terminate $ and the 60 that :ess effort is required to produce ey =gmpios rem @ud from the, Wire is to be metaf coated, a hmocth, wel1-wrappe$ splice.

h.

oven. The emer four sampR c The tape is appiiod over the two Resistance to UltraMest are to remain in the even for a wires and firmty rolled down with a MA 39 DectrkW Tmmw tola! of M cays, and are then to rubcer rener. The wiree are cut Rush is at one end of the tx>ard with two as are at availaNo corapethJvt continuously underpobg u vinkrs-be removed from the oven and flexed, in e ach case, the inches of wires extended at the othef violet exposure tests. 3M haintair.s samp!es are to be cooled at end. The board is then hung in a an outdoor aging fdty 4 Sugar-room tempera *ure (73 : 2.0*C) conditoning chamber maintained at lar4 Teru, WWm of me for no less than 16 not more 95:1% R.H. One wire from 6ach high naber of sunshine (ays.The than 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> before being sampie is connected to the pese.tve Oaft air present a!60 acce4 rates the flexed. side of a 250 vort DC suppty and th' aging condalona.

4A. The fiering is to be performed other was are connected to the Various tspes are wrapped on var-by holding the wire of the negative side.

assembly approxi ate!y 1 inch 250 votts DC are appfled across the f![num, st and, nt o est 8 " boards. The teards art p sitioned a ag n a nzen i fxe 1/2 The sarnp'es are then removed. the such a manner as to allow arposure to inch diameter steel mandre!. tapes removed from the wires and the muirnum suntyht.S4mples of the The end of the assembly whicn tapes are also plac;ed orntalnisss

!ncludes the sphce is then the wires are tested for tensUs strength. The corrosion factoris steel plates andlikewise mounted on wrapped tightfy around the test toe /da.

found by calculating:

marcrelin a clockwise directicn untd approximately one inch of Tensue of pos!tive wire Alltapes being exposed in outdoor the wire to the rignt of the spfice aging are testedinttially 4 order to Tensim nf negative wke establish before exposum der;a. At is wrapped around tne mandrel.

Th< cirecton cf the wrapls then Electro @c corrosion will not affect six month intervals the ro:ia and reversed and continued in the the copper wire connected to he plates are removed and sent to the counterclockwis,e cirecoon untd negative side of the DC supNy. St. Paul tabs for testing he tapes approximate!y one inch of the However, any etectrotytje corrosbn are tested for the following proper-w:re to the rignt cf the splice is cosed by the tape wi!! result in the tics; wispeec arounc the mancret. essolving of a small amount of the 1. Observation of sut. bee i Fes clockwise operations and w:re connected to the posttive sde of 2. Cobr i hve countercl0cicwise cpera- the DC supply resutung in a lower 3. Adhesive condition l tiens fcilowed Oy a ciochse tensde strength. A Adhestve Mtbn @ rod

unwrap completes the flexF A tape whose electrotytic cocesion 5. Corrosion on red

'*"' pmcem factor is less than one could be 6. Adhesionvalue(cz.tch)  !

All operations sha:. 'e con- considered to be damaging any 7. TensPe strength (bp) ,

ducte:I at 3 un:fcr ' - 3such ccpper wires it com9s into conta0t B. Congation (%)  ; j that the fu4 flexing - s;edure 4 with at high relative humidtties. 9. Oletectnc strength ($tta/ inch) l completoc in 20::s seconds. Scoten 33- Electrica) Tsoe has an Scoten 3b EectricalTW has '

The tape sr all not crack or electrolytic corrosien f actor nf 1.00. been cesigned such ma(tts proper.

butble afte: being f exed. _

ties remain virtua!!y unayected in this 9 outdoor or aging taat.

The conductor shali show nc 'T 8"W W acvorse effects after remova! ef ___~ Conformability tre tape fibm the splices. Type "r tape is a ste ' odented Electrolytic Corrosion A^?,7.L mm rype product. ttis dr scutt to N

In insu!ating wires, c'ectrolytic corrosion caused by insulat:ng tape h_

lp -C 4 k"Z'"" elongate and when stnH::hed beyond the low yleid point it deat not recover, can result in f al!ure. When subjected 1 Cr.soquentty R does rot conform to Q

to stress under high humidity, an j frregular surfaces and ptytde ade-Quate splice protecuon imm trosture insu! sting matenaj semes as an d electroryte or a medium for the g$

'[

, ,,gma even though it is "rnoistyre res!stant tas ' Sea Fgure 5.

solutionof cepper wire whenleaka;,e current exists. The 3M electrotytic (N l iI N

k ~P" ,

certosion test is a scientfic method of measuring the ef'ect of corroclon h

! lt Ig

] mm g4 M*< n.

caused. an insulathg tape on a N i

l. mN

(

4 cooperw . It is based on tensile h l - ,

la ' I.[ 9 lw ,

strength m.asurement of a copper wire which has been exposed to >_ -

e!ect otybc corrosien.

f J ., . ___ --

,i+fse[m"****"' p ( Q.uQa-w cusw.z: n,e

- 1 ~_l

' ~

A preparation boa'd is made by wmO- ~]&

P . ,s.

< ping No. 32 gauge copper wire sc ' hat i sets of two wires are soa ed 1/4*

acan. Addit Ona! sets may be placed W The Scotch 33 + EW-J Tape Cross Seccon of curve I!!ustra!es thM noen the tape la 1/2" apart. The wires should be snug, applied wtth normsJ tension a neat, but must not be stretchec er kinked. Cor esen Chamber

.____-_______-___________________________________________________[____

~~ - - - - _ _ - _

self snugging splice is obtained.The resuttiS a good looking, moisture-

. PfoOf Sp0C0 that provides escenent physical and electrical protection.

6. Installation Techniques The tape shall be applied in hatf-lapped toyerc with sutf.cient tension to redVCa its Wid*Jh to S/8 of its origtaal width. On pigtsit splices, the tapa shs!!be erapped beyond the end of the wires and then folded back-leaving a perfect pretnive l i

Cushion Which will resist wire cut.

tr. cough. Alwaya wrap tape uphill. DO NOT STRETCH LAST INCH.

CAUTION:The adhes!ve of 33+

f*

Tape is not oil resistant. It should not I be usec for solc ineatation on cables Which contain oil or slippery corn.

pounds. The tapo should ret be used where oilcan attack and soften the adhesive. '

7. Maintenanco Scottn 33- E!ectricalTr.M si stabte ,

uncer rer*nal storage conc:tions.

Spe:ial sl:mng M.inieves te sutt in a tape Chich will not te! esc 0pe. A spectajy icrmu ated rubber based adhesive remaina stacie under a!!

weatser conditions.

8. Availability ,

Scoten 33 - Vinyt P:asttc Tepe ts IM N W MTM*-

avaiabte in the fonowing rott sizes I Ao statsments, tectwcs1Intonsstion and .

from your eie:tricaldistnbutcr: ,3,y, g, 14 in. x #6 ft. basedon teatr ws be6 eve to MinsaNe, 4A tutthe m eyocoom se,ee ,

14 !".

3:4e *x 20 tt. thereoffs not guaranteed, ant the .

m ensn$ss, fo#cwMis made h#eu ded S'4 in. x 66 ft. Is a!so avallable in a

• W W WI W8 8W manufacturer's armyetegafdi 6%f De <

handy, plastic c'ispenser' ta r$ ace such e.eanceyc(toproduct Other lengths and widths are ava 1- proved te be defaceW.WtW aederace manu'ecarer shaR be BaGe Ipr ay able by special request. ep,ny,Jo go.geiage M or conse-vomplete Product and Use Specifi-geenW, arfeing out of the usr oforthe cat.Ons are avai!able through the baboryto use tw prodvet.1 mare Ele:*ro Products Diveien,3M ashg. uesesh-2 cetermha En autsb %

of the productkrMs breedesiune,sno Company. my veerausumu aonok edse whatacuverm conneesbe euwre. No ara.wnent orrecommendsf4n not bety force or Centabed hertelr1 thed have e#ectuniese h an ecreermn' W by omcers etasser m(manveturer.

>-u

• * " c* _ <

Electro-Preduch Division /3M 225-4N,3M Center St. Paul. Minnesota 5514 - - - - - - _ _ - _ - -

REFERENCE 9 hEMORANDUM l To: File  !

From: J. A. Murphy Date: July 11,1990 Subj: Elevated Temperature Behavior of Sectch 33 Insulating Tape The product information bulletm on Scotch 33+ vinyl electncal insulating tape supplied to MLEA does not etntain any information concerning the behavior of the product at temperatures above 113'C (235.4'F). I therefore contacted the 3M Electrica1 Specialties Div in Aestin Texas (512 984 5657). The operator connected me with Mr. Steve Meyer (International Technical Senices) ar.d asked if there was any information on the behavior of Scotch 33+ at elevated temperature (viz. 300'F). He pvided the following information:

At 300*F aftar a period of time the plastkizers used in both the tape and adhesive will volatilize and the tape becomes brittle.

. The tape, if it has been stretched dnring application, will also attempt to shrink tt its utstretched configuration.

There is a threshold tempenture for thn behavior and it is probably above 250*F but he could not provide a specific number.

I asked if there was any question about the behavior of the tape at 113*C. He stated that th9 tape should routinely pass the test conditions stated in the product bulletin. He also stated that above 105*C the tape and adhesive softens somewhat but could not quantify this informa* ion.

I told him that we had been running a thermal aging test in which Scotch 33+ was used as a jacket over Okonite T-95 insulating tape at about 300*F and that after about 40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> the Scotch 33+ split and was brittle. He stated that the observed b;havior could be expected based on the fact that the plasticizers had volatilized and the tape had attempted to shrink.

I thanked him for the information. (There is no published data on this behavior because the product information limits use of the tape to 105'C) l

.