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BULLETIN NO IC/FF 38 HONS A. Visual Inspection............................................13 B. Dielectric Breakdown Voltage ...................13 XV4I. Inspection Checklist..............................................13 XVIII. Contamination in Transformers...........................14 Table VI -- Effecl of Common Insulation Materials on Power Factor and Dielectric Strength............................................... 14 Table VII - Effect of Common Insulation Materials on Volume Resistivity of Askarel............................................................... 14 XIX. A$TM Method for Investigating tha Compatibility of Transformer Insulation and Construction Materials in Askarels...........IS XX. Refining Askarel for Re-Use............................... 15 A. Filtering Through Dry Blotter Paper to Remove Moisture and Extraneous Particles....................................... 15 Table VIII -- Water Removal by Filtering Askarel Through a Paper Press ..........................16 B. Disposal of Solid Wastes ............................... 16 C. Solid Insulation Requiring Drying............... 16 SECTION A D. Earth Treatment for Maximum TRANSFORMER ASKARELS............................................ 1 I. Introduction .............................................................. 1 II. History of Trate NameTypas............................... 1 Table I - The Composition of "N Improvement of Power Factor and Volume Resistivity ....................................... 16 Table IX - Effect of Power Factor and Volume Resistivity ..........................17 Transformer A ikarels .............................................2 XXI. Cleaning Arced Transformers............................ 17 lit. Interchangeabl lity .................................................. 2 IV. Table II - Off cial Transformer Aikaral Shipping Specifications..........................................3 XXII. Sampling Askarel..................................................17 SECTION B V. Ordering Initn ctions .............................................2 Q ASKAREL FILLEO SWITCHES VI. Stability..................................................................... 2 AND TERMINAL CHAMBERS ....................................... 10 VII. Precautions Wi en Handling Drums, Tank Cars I. Introduction.......................................................... 19 and Whan Opa ting Transformers......................... 4 II. Sources of Contamination ..................................19 U- iv!A. Kaop Dry I luring Handling ............................ 4 Table III - Handling and Staling Switches and Terminal Chambers . . .20 Askarel Used Under Mild Arcing Conditions . 20 Pumping T tmperatures.....................................4 Maintenance for Askarel Filled Switches ... .20 B. Use Ordina y Personal Precautions ...............4 * P C. Precaution! on Opening an o r- Askarel Under Excessive Temperature or Fault Conditions ............................................ 21 VIII. $Askarel Tri nsformer.......................................... 5 /- SECTION CO Avoid Environ nental Pollution............................ 5 O x 1. Labeling A ikarel Transformers.......................6 ANALYTICAL SERVICES ON 2. Disposal of Liquid and Solid Wastes ............6 V) I TRANSFORMER ASKAREL JX IX. X. XI. XII. 3. Conditioning of New or Recycled Askarel .6 4. Teardown >1 Transformers for Repair Dr Scrap .......................................... 7 6. Transformi r Disposal........................................7 Expected Sent ce Lift.............................................7 General Chare iteristict of Transformer Ol'U Askarel Fluid ...........................................................7 Sampling Tran (former Askarel Fluid ................. B Evaluation of kdtarel Received (=5 In New Equipnant.................................................. 8 Dielectric Brti kdown Voltage - M - AVAILABLE FROM MONSANTO................................. 22 Types of Analyses Available: ............................................ 22 1) Routine Maintenance Check.......................................22 22)) Complete Analysis.......................................................22 _ Analysis After Earth Refinement ............................ 22 Tppendix A - Askarel Stability and Composition of Arc Formed Gas.................................... 23 Appendix-B - Solubility of Gas in Transformer Askarels ....................................................... 23 Appendix C -- Effect of Temperature on Dielectric Breakdown Voltage of Askarel ....................23 Moisture Retekmthip.............................................0 Appendix D - Comparison of the Approximate Table IV - Relation of Dielectric Breakdown Voltage to Anr ount of Dissolved Water in Viscosity in Saybolt Universal Seconds of Transformer Askarels and Mineral Oil............................24 Askarel and M nerat Oil.......................................... 9 Table V - Api woximate Solubility of Water Appendix E - The Density of Inerteen 54201 KA 7336-9 and Transformer In Transforms Askarel and Mineral Oil .... 10 Pyranol A13B3B3............................................................ 24 XIV. XV. Turbidity .................................................................10 Check Points I or Maintaining AAarat I nsula lion ................................................ 10 Appendix F -- Thermal Conductivity Values of Transformer.^yxatol-A13B3B-3................................. 24 Appendix G - Heat Capacity ............................................24 A. General C< nsiderations...................................10 Appendix H -- Coefficient of Expansion......................... 24 B. Modern Selling Procedures .......................... 11 Appendix I - Fire Resistance............................................ 24 C. The Older Sealing Arrangements.................. 12 Appendix J - Seals. Properties Periodic Fluid Inspection and What Checkpoints Mean ..................................... 12 and Procurement ............................................................... 25 Appendix.K - Caution Label............................................ 25 M o v e c tu c lR tm e r -fp h e r e j y rn q oI HONS 074745 I I I ] NOTICE: "No*hl twrcln Is to ba c recommendation product In conflict nt. MONSANTO WARRANTIES AS NESS FOR A PAR POSE OR MERCI OF ANY PRODUCl TO, no guarantsa results from rsltan| (alnad Information datlona, and dlaclal for any resulting li * "NOTE: Materials designated 'fire reefalanf generally are more dif ficult to Ignite, or once Ignited, burn at a slower rate than cor responding conventional materi als. This term does not mean that fire resistant ptatsrials will not burn. However, nwhen proper- j* Iijyr uvsedu., Mwiounnssamnitiou's fire resistant /yPWRAUL' ll`llPWAULie FLUIDS are useful in helping customers meet their fire safety require ments." T i *' 1- r i I. Introduction The term "askarrl" as defined by IEEE. ASTM end the Nation:' f.kuncal Go.it* I. ,'v'i)ltv fiosrnb..1 ho.-d class Of r.un-tUntn.abl,. synthetic chluhnoltd hyrirocaihon imukwinc linnd:. wif.VIy m transformers, reactors and accessory equipment operated at powot frequencies. Askaicls of venous compositional types ate in n;e. (K the general properties and types sec ASTM 0*2203J LiM.er arcing conditions the gases produced, while consisting of ptcdornirvintiy non-combustible hydrogen chloride, tan contain varying amounts of combustible gases depending upon the askarei tyie. This manual dosciibes the operating chiuactr-risiics of transformer askatel liquid inr-ulalion and how it (.fitters from mil .rai oil. Appropriate handling and disposal procedures for both sciau atkarel liquid end impregnated solid mateiials are given in accordance with the guidelines recommended oy the Amctican National Standards Institute. The information i' b?red on fuels tj.tf.erc.f I"/ i.1.^,s t,ime U veers a i' I'f.idcr. f of *k.;t , pfti:. i.no./ti d_ v from the expei i-nce of tiwiiaiinmcr ivteiitn'arhin-rs end ur-uis. l itis guidu oudint.s d ; fii.;piir maintenance re'juircd for askarcl fluid in "ineoem" tifinsiormers and o Tars suggestions for sealing and maintaining oskarel in ok! tn.is. By fc'lowmg this guide, we believe users will cbiain nvximurn set vice from ;.bkarel insufation with a reason; hie minimum of maintenance. If questions arise relating to the designing and building of tiansformers, these should be referred to regular transformer suppliers. Mi.'nr.anfo gratefully acknowledges the assistance, guidance and the contributions of certain data by the following: xlward L. flaab -- General Electric Dr. T. K. Sloat - Westinghouso Electri,cc , . if. -J i t. . < nr> f H. History of Trade Name Typs ^ti r<'r 'Abki.1 el" is the genci ic name for the non-eombtnTmlc liquid insulation nr:! cuqJfir>i. firr.|.uff`d by Gqi'ral b>:ctric Ccmpmy in 1932 lor their Pyranoii brand name fire-resistant transformers Wcstinghouse Electric 'Corporation uses their brand name, Inerteen.**' - \Vhatever the trademarked brand, the eskarcl contains chlorinated biphenyl -- one of the best liquid insulations developed by science. This inert material is chemically stable, fire-resistant, heat stable, non*ccitosive, and has high dielectric stiength under the ooerating conditions encountered in transformers. In addition to manufacturing Aroclor (chlorinated biphenyl), Monsanto also mixes this dielectric fluid with chloiobenwies to ixoduce the presently used Incticen and Pyranol blends described in Table i. ^ o* Genp'fll t-trenie Compacv '"*Tr;iOemenr of Westinflhouse Wocmc Co>notation ^Hegistered tmtieinerk ol Monsanro Coomkhw HONS 074746 II ~r-- I Table I Tho Composition of Transformer Askarel* y p \ -. '' fr ' Method ASTM D2283 I Type D Typj C Type G* O { Trade Names Inerteen 70-30 IncMcen 100-42 Pyranol AJ30303 T rK /" Ingrodients f% by wt.) ^-: jcnh (o * . 'I MUi . C. U . Plf v- , Aroclot* 12!i4, .! pcnlachlotobiphenyl v 70 , 60 Arocloi*' 1242, - '1 trichlorobiphenyl - 100 *"* . "richlorobontcne ! 30 rr {.henoxypropone oxido --a. * 'cuvenger 0.18 10 0.22 0. IB lo 0.22 5 -iinpoxido'scavenger j 0.115 to 0.135 ^"f-Vthod-d 6TW P- A$TM Method D-2283, titled "Chlorinated Aromatic Hydrocarbons (Askatels) For Transformers", also lists the composition of all transformer asknrels usedjat various limes since 1932. Monsanto manufactures Isimilor transformer askarel fluids in England whore ih j trode nemo Pyrjoclor is used. III. Intcrchan^ (n genera/ all tram formal askarels are interdu.n^able. However, if is suggested that the transformer manufacturer be consulted prior to mixing in significant proportions or total substitution. IV. .''.''.:-'-lTransfnrinor Aikarel C'.i,' ''"'.'-Specifications n';^i*,^i,rr,'rdn.7.. pacifications for the three modern transformer tkarei fluids era shown in Table II. V. Ordering Instruct!) ms Monsanto's current poli< :y is to sell askarel transformer fluids only to transformer manufactun Others interested in these fluids should contact the manufactun |rs of askarel transformers and not Monsanto, The transformer name ploto indicates the transformer maker and usually gives sufficient |ata to identify the specific askarel fluid used. Vi. 6t.>WHP:<Conjl ounmario n iryd Jisx kkm*de-wndof ele eheini* eempoeitmwkik'g'the eowmeteiel^P-ngfr^fr-- Askarel insulation must] never be mixed with mineral oil. Over two percent of mineral oil jjy volume in askarel begins to lower its fire resistance. j In modern transformers, the esUy^roal- "enemy" of askarel is contamination by water. Keeping askarel water-free will insure long-time service. Askarel is heavier than vjatcr. If water gets into askarel insulation, only %\ .t .oy i 'Z <t k * Q . i L' -V- HONS 074747 T o t> O -4 35: Table II 0 OfficiulTransformer AskarelSpecifications t~ 1 -* ' g3 3. a *l ** o* ^02. - ! 0-0 ** 2 1 Specification Properties Color. APHA Condition Water content, pom (ASTM 01533*60) Acidity, mg KOH/g (ASTM D974-55) Dielectric Strength, 25VC, 0.1 in. gap (ASTM 037749) Dielectric Constant, 100 C, 60 Hz (ASTM 0024-49) Volume Resistivity, 100eC, 5C0 voits DC 0.1 inch gap, 109 ohm-cm (ASTM DI159) Inorganic chlorides, ppm (ASTM D1821 and C.6. Method E4C41B) Refractive index, 25fC (ASTM D1807) Viscosity at 37.8C (ASTM 088-56) Saybclt Universal Seconds Puur Point *C (ASTM D-97-57) Specific gravity 25/15.5C (ASTM 01810) Burn point (ASTM D92) Distillation range (ASTM D20-56) corrected for stem and barometric pressure Fixed chlorine Corrosion test Color, APHA Acid'ty. mg KOH/g Inorganic chlorides ppm Condition Scavenger content Typical Properties^ * o tA General Electric Co. Transformer Pyranol A1C333-3 ASTM 02233 Type G- 150 max. Clear 30 max. 0.014 max. 35 KV, min. . 4.2 to 4.6 Z- Westw^hoose Transformer Inerteen 70-30 ASTM 02233 Type 0 150 max. Clear 30 max. 0.014 max. 35 KV, min. 4.2 to 4.5 Westmghcuse Transformer Inerteen 1C0-42 ASTM 02283 Type 6 60 max. Clear 35 max. 0.01 max. 35 KV, min. 4.7 to 4.9 100 0.10 max. 1.6110 to i .6120 44 to 43 38 or lcwer 1.495 to 1.510 None to boil mg 1st drop 20CC nvn. 40% max. below 270*C 90% 379 to 334 ICO 0.10 max. 1.6153 to 1.6173 56 to SI 30 or lower 1.518 to 1.528 None to boilira 1st droo 20C'C min. 35% below 27G'C 90% 379 to 394 100 0.05 max. 1.6240 to 1.6260 82 to 92 17 or lower 1.381 to 1.392 None to boiling 10% 325*C mm. 90% 360 max. 56.4^0.5% 55.6% nin. 43 0.5% After heating with aluminum for 6 hrs. at 200 to 22GC, the aluminum must not be corroded on either visur.l cr weight inspection and the sskarel should meet tne following specifications: 200 ms. 200 max. 200 max. C.014 max. 0.014 max. 0 01 max. 0.15 m?x. 2.0 max. 0.15 max. Clear Clear Clear 0.115to 0.135% 0.18 to 0.22% 0.18 to 0.22% Diepcxde phenoxypropene oxide phenoxypropene oxide Coefficient of Thermal Expansion TWl Dt903). cm2/cm?/C formed gas^s 00007 0.0007 0.00053 Askarcls of various cenpojitionai types are used. Under arcing conditions the gases produced, while consisting predominantly of nor oambunible hydrogen chloride, can include varying amounts of combust'ble gases depending upon the askar<H type. Insulation systems incorporating these askareis ad celluiosic or other oceanic materials may. when arced, produce gaseous mixtures which are moderately flammable. As a precaution such gases should be removed from the askcrcl hy bubbling dry nitrogen through the ast.arei and flushing the gas space wir> dry nitrogen before any work >s pert jrmtU r;n the apparatus. /`Westirvihouse uses then p-'vau number treceen 54201K A tor Inerteen 70?n and ti-eir private n-jmhc* Insrteen 54201 CM for Inertr-m 10042. '1 These ociAfttiti'cs rt ?- iel. sa.les Sfi<i^icAi.'is *l"ytoto tine extent V puM'i tlied $ i sci i e ' $, . *n*T . th*y a liny amount (approximately 125 ppm) dissolves - the rest floats on ,\ top. Askarel is very insoluble in water, only about 200 parts per billion ' \N of atkarol dissolve in water! at normal temperatures. VII* Precautions When handling Drums, Tank Cars, end When .J" Opening Transformer* I --i >5 n- The American Institute oj Electrical and Electronic Engineers Guide ! ' No. - lo$ h-tt dprrrTevifr*u~u>' gives more detailed ,, "O// instructions and guidance "For Acceptance and Maintenance of r" ' \ t/e- &'t'C Transformer Askoref in touipnient". This guide is published by the [u*tY-S I Institute ol Electrical & {Electronics Engineers, Inc., 345 East 47th it) F Street, New York, New Yojrk 10017. Wii f < l crn < n ^ )}, >/) ref rr/?r>!>/o r t'Cfir /<: tiU$ ^'C < <- <*tr4 iw The following ate significant precautions: ^ '......... A. Keep Dry During Handling: In handling, storing,' sampling and inspecting nsknrel -- end in operating nskarol transformers - take every precaution to guard the as!crel insulation from exposure to high humidity and moisturo contamination. Ko-'p 5 or bb mllon drums ol askarel dry; ley stored drurre on their sides with me burg at iho hignest point from floor to keep water off the di um head {which con be sucked into the askarel by the drum "breathing"). This precaution it not necessary whhn drums are stored indoors, which is the prefer ted place for st^rrge. To avoid leakage the drums u:.cd for askarel aro of heavy V construction. Sixteen gsuce mdul is used, with special rim seat and l\ bung construction. Tjhe drums strould l e drained as completely as I ` possible end then flushed twice with kerosene type solvent to * remove all of the eskarel. Accumulated liquids and washings I should be collected a id should be incinerated at hi;,h j tompamturcs, e.g., apout JCCO'F, to destroy the polycblorinr.h.d biphenyls (PCDs). Sej> Section A. VIII. . D. ,w'0o fcs'viis s' Tank cars used to transport askarel* are 'n exclusive service and not urtd interchangeably for other products. All cars must oe unloaded through the top (dome fitting) either by pumping or with controlled pressure using dry air or dry nitrogen, if nitrogen has been used for unloading it is necessity <xivue the shipper so that when the car returns the nitrogen can be replaced with dry air before any one may.enter the car. If the car is to be unloaded by pumping it will be necessary to use a dryer on the air intake line to remove moisture. All Unk cars are fitted with steam coils, which are available (or unloading under txtfema low temperature conditions. ft i Convenient handling and pumping temperatures antl^?>efcwstl j^pjmvtniriftirVeifit-"'rP*T,`"~ in Table III. B. Use Ordinary Personal Precautions: Transformer askarel pas bo*n made, handled, and used for over 40 years. It can be handled safely with recommended precautions. If accidentally spilled pn hands, no serious skin irritation will occur. However, liquid askarel has a solvent action (similar to paint Product Table III Handling and Pumping Temperatures Unloading. Handling and Pumping Temperature *C Aw Pyr.nol AI3B3G3 Inertcen 70*30 , Inciteon 100-42 20 55 20-55 35-75 K*--W HONS 07474S /I f thinner) on the hits and oils of the skin and piolonged com ct may lead to riryiny and chapping of the skin. In case ol comaii, wash ihr skin with soop and wafer; remove and dry clean saturated clothing. Clean up spills with rags, sawdust and ahsoibent day. Eye contact may icsult in piirdul irritation bin no permanent di-magj to tissues. II atkaref gets in the eves, Hush wnh large amounts of waier. As with alt eye fust id, ich.r to a physician. To relieve itritafon, physicians have used an opthalmic anesthetic solution as well as upthahuic cortisone acetate solution, or castor oil. Infrequent exposure to askarel vapos will not cause ill effects. However, prolonged exposure to high vapor concentrations should be avoided. II hot askarel must he handled in a dosed or confined area, provide the area with mechanical exhaust ventilation - or wear an orgonic carttidge respirator approved by the U.S. Buicau of Mines. C. Precautions On Opening an Askarel TtandorrniM : Askaiels of various compositional types arc used. Under arcing conditions the gases produced, while consisting ol predominant"/ non-combustible hydrogen chloride, can yield varying arno mts of combustible gases depending upon the askarel type. Insulation systems incorporating these askarcls end crl'ulosic or other organic materials may. when arced, produce gtreous mixtures which are moderately flammable. As a precaution, such gjs<?5 sftotild bo removed from the askarel bv bi'kbJno dry nitrogen through the askarel and Hushing the g:s sdjcj with dry nitrogen before any work is performed on the apparatus. V!ll. AvniH Fnvirmtmi 7ran<fomci ssl-crcis contain po/d'.'onrctcd bmt.or.yl. (TCRs) which hove been used in the United States and elsewhere over tl.v post 4Q years lor many industrial and consumer applications Duong Hut past several years evidence has accumulated to ind'cne mat PC:<s arc widely dispersed throughout the environment and that they can have adverse ecological and toxicological effects. The United Slates Government's Interdepartmental Task Fore? on PCBs, Conri'72-10419. in their March 20. 197? report titled, "Polychloi mated Biphenyls and the Environment", recommended restricting PC3s to u:.e in capacitors and transformers. This report is distributed by tire National Technical Information Service, U.S. Department of Commerce, Springfield, Virginia 22151. A document titled, "Guidelines for Handling and Disposal of Capacitor and Transformer Grade Askarels, Containing Polychlorinated Biphenyls", has been prepared and is available from the American National Standards Institute, Committee CI07, 4*5 F*st-.t4ih.Street,* New York, New York 10017/ I i s, ' i: ' 0 it . ICOi o. The scope, objectives and the composition of this committee are: ANSI Committee C107 Scope: Procedures and guides for safe use, maintenance and disposal of askarel and askarel soaked materials used in electrical equipment. Objectives: \. Source of technical information and advice for Federal, State, local authorities and all others concerned. 2. Encourage development of suitable disposal facilities and keep aft concerned informed. 3. Serve as the advisory group for United States participation in international organizations CEE. IEC, CIGRE. MGNS 074750 1 -4-- Composition: Oigamrotiom active in or rervcsentpd bv this ANSI committee include: National Electrical Manufacturers Association, Electronic Industries Association. I Institute of Electrical and Electronic Enginocrs, American Society for Testing and Materials; Elect.ic Light and Power Association; Certified Ballast Manufacturers Association; Environmental Protection Ag 'ncy; Office of Environmental Affairs, general Services Admumtiation; National Bureau of Standards; Department of the Army; Rural Electrification Administration; Division of Environmental Research, TVA; American Public Power Association, Water Pollution Control Federation; Food and Drug Administration; National Fiic Protection Association; Underwriters laboratories; and soverai sections of the U.S. Department ol Interior. The following are portinent pxcerpts taken from the ANSI Guidelines for askarcl bnnsfotmers: ; _ I> VlABeTTnFasKaIiEI TRANSFORMERS (P>. It) 7-*<> - j; /7Uc^i^r.T,m:rg^ir-Tor---------.J .r o.s'y rr ,. 5 '-vuW--r >(r|-'r'*j 1-V '*'*{: .'-Mf+f -X-'**-vnfirfrrmt'"n,4f.t+R'--CTj., T !*. !' yiu.-_ / L. ' !?*>.. I j I , ;i iJ.: ,<n /. A An ' f,n) /ih (/) i'iX-t*- r-'t-m1 r.i-v.-T-' to W yKl-i'Jx: i wn.a4J4iivw--; DISPOSAL OF Llduin AMD SOLID WASTES ( ) e tfjvomultshed by m'ans in which there is no sinniticai please A fskarel t$ the erv/iiounv.nt. At pn At, disooset iCComplisiv:d hy 'carcd'lly controlbd ..njh tcmneraun*: . ncincratio.n o' htnuivls and soakrJ software; and b'f , ^controlled dys>iiddill burial of apparatus and ott Trihardware from whicif'ukartt I' js been previously drained 1. [washed. i xs. j Present knowk,fl;'i' indicates thuV-noper incineration shoulr nvofve a s.is/abJ^ balance ben,vn dwell time anr l\mperatJ.v^F, m the incinerator pius oxp?*n availability anr |finaUy'>suitable scrlrbbors to remove HC1'"f^cmed; e.g., (1 /two-second dwell (lime at approximately 20CT3"F and 3" I excess oxygwn in slack gas; (2) 1-1 Vi second dwell time a| The ANSI Guide hits the locations of facilities that conform with the above (requirements. Monsanto has such an incinerator at thej W. G. Krwmmrich Plant, Department Sauget, Illinois 62201, where arrangements can be made for .cran asknref liquid disposal for a modest fee* ---- 4rspwsaiBWfc For disposal of solid scrap a ***contiollcd Uiy lanrl fHl can be used where permitted by Federal, State and local regulations. 4.2.2.l**Now TransfonnctS. All new transformers Filial contain PCBs shall have a label of adequate durabil ity, pcrmancnlly and prominently attached lo the lank by the manufacturer, giving adequate wanting and in junctions. A suggested label Includes the following; CAUTION- The insulating liquid in this transformer contains polychlorinated biphenyls (PCBs).Caic should he taken to prevent cnlty into the environment. In case of malfunction or leaks, consult the instruction manual or (he manufacturer. . 4.2.2.2 In-Seivicc Transformers. The transformer manufacture) should make available suitable labels with t^ hi ._____a similar warning as shown in 4.2.2.1 for use on exist ing transformers. ^ #4.16.5.1 General. Disposal of askarcJs and iskarcl-soakcd materials should be accomplished by . means in which there is no significant release of askarcl fo the environment. At present, disposal is accomplished by carefully coni ioiled incineration of liquids and soaked software, and by controlled landfill burial of apparatus and other hardware front which askarel has been previously drained and washed. Present knowledge indicates that proper incineration must involve a suitable balance between dwell time and temperature in die incineration plus oxygen availability and, Anally, suitable scrubbers to remove the IICI (hat * will be formed; fur example, 2-sccond dwell time at % 2000F and 3% excess oxygen in stack gas, or 1.5- [ second dwell time at 2700J: and 2% oxygen in stack * ga*. i These facilities should meet the applicableicquire- 1 merits of the state in which they ate located and should control effluents within the limits set forth in this stan dard. | | Controlledlandfill or deep-well disposal can beused I V Wl--Vewhere permitted hy federal, stile, and local irr.uknions. * | 3. l \J CONDITIONING 0|F NEW OR RECYCLED ASKARELtf}.l* rrrkei el~ ur vSr>x:rth tioatriient. The spent Fuller's earth tu-er;r'tndqi I ir rags whehxaLnccd should be alloweifj/KifToroughly <ti fwl drip pans to rb>*cxas nr.ich^irfuiri askarel as possible lh| cartridge unit's iX-- comtiuction should i> la/ed in lhcXS^^Lonti1llMutl^7v.'.^,Askrtre^, contjuvl \uJiihi>ni*TlCn7cio\u b,7;'. t fIcel will. F uIIvi"T*7ji ili^Qnukl hi l.i --<T. the^Sewr ** 1 * rW V '. Jr ai 'S. MCNS GMJ51 1 L. '! 4.g'.4.4 'fliwutaWn of0 4.2.I.4.I Drain all askarel from the unit cither into holding tank far reuse or into the drum labeled "SCRAP ASKAKEL'i for disposition, and then allow sufficient time for all of the askarel to diain from the core and coils. 4.2J.4.2 R< move the core and coil assembly from the transformer Sufficient absorbent material should be placed on l >e floor to absorb ntiy askarel fluid that still drips from the transformer. 4.2.I.4.3 Pliice all materials in the appropriate salvage containers during the dismantling for hter dis position. ' Af'.mWN OF TRANSFORMERS FOR REPAIR OR R'*r* { i\. tG> I : i-i'- <' h..u m "ui'u.i? * ".'TrrrY^ it-.i "ociiip . i . t ' no - ; then allow sufficient time for h ' ; Jram . 1 core and coils. L '' || move ti<*: ' ^and coil ,_inbly from . V.nsformer ant) , '"'v it.. J. "'the Moor. Soffici >)SOrl:cnt material sh , loced on the floor .sorb ny ask.'- ,,.jnj i. , '( drips from `ansformer. ... iiare all r V idls in the appropriate si i uriei. 4 innf ^ ; dismantling for later disposition, 1 -jd materials, including mgs, sawdust J\ ^ . .aidless of ii'nritity, should be Ldu!. V A,f uscd n>'crialS. including "r,, " .',, PC' "C- of quantity, 5llall br ^ TRANSFORMER DISFOSAI. (. Ci .ill __ if------- -4.2.1.6 H ml of nil iwkarel-filicd transformer inay be accom- thed In either of two ways: |r (I) Complclc drainage anil dismantling with the :. per disposal of (he askarel and askarcl-soakcd com- j, enls in described in 4.1.6r I l) Disposition of askarel transformers by means of ; or scrap dealers. This should be avoided unless a i pormn is first drained, ijollowcd by soaking (he ; ^ >r with a suitable solvent. Accumulated liquids '' idlings are (o be disposed of as described in 4.1.6. -J ( . V. - -. '.1 s(-r.UaoitA. r; a': ."'mtrii I'.c'l in riih-r of two w?'1? >. Cl".iv.'hne diainage and dismantling with the pioifr [ dispose!'... 'tv askarel liquid.. tuK components as l .'"'ri ah-ve. ' ' ^.jf^OispositiO1'* of 1........ 'mmeri by means cl soak'd scrap dealers <> cud be avouic-t a tran-.lormeij ffsl drai-'.vyt,' loilowad by soaking of mv..'tenor ffjitcbKT^solvent, such as kerosene. Accumulated lipui;* nv '. ,y_ j. i.'<. lT;:p.-'ctcd Servico Life t.'..uuitant'jiC's indicate that properly designed and installed askarel transformers s'R expected to give trouble-free service for *t lc ist 30 '-..'rs. Since their i'-'ti c d "C.;rm in 1922, the manufacturers report i,,t,',j the ov'i.ill failure r ;i-: to be less than C.B'ij for all u iit-, under lost anti service conditions. The Edison Electric Institu'-'r. report i Jvf-> on their tn-' n:;-:ri utilities ncb'ahcs the failure rate for ! aral t: ansformers as 0.12 per hundred banks per year. ,.!r. Frank M. Clark, who invented transformer askaruls at the General f-lurtric Company in the early 1930s, made the highly pertinent c n ntent ba'f-d on his many years of experience with G.E. Pyranol l"s' etiol type) transformers that -- 'T/re important thing is to keep them dry - otherwise leave them alone". These words of wisdom became especially applicable in more recent years when welding shut rather than gasketing became the main method of sealing askarel transformers. These units are sold with the understanding that the liquid is in a normally hermetically closed system. 4.2,1.3.1 Askarel clndiilonlng Equipment. 1 /file conditioning unit iliould he located eithci in the I / alotage tnnk area ot in the main transformer mtrmifac" m luring area for filling with tsljarcl. Ijfl 4.2.1.3.2 Fuller's Earth. Conditioning of new r 1 Bikarel or recycled askarel requires fuller's earth treat ment. Tire spent fuller's carll) in cartridges or bags, s0whnt replaced, should be allowed lo drain tborouglily owl drip pans to remove ns rjruch liquid askarel as pos- llble. Tire cartridge units of siccl mesh construction dtould be placed in the "STBHI. CONTAMINATED WITH ASKAREL" contaiucj Tor disposition. Cloth bagl filled with fuller's earlhjshuuld be placed in the "SCRAP BURNABLE ASl'.An EL WASTE" container h for dlipoillionf*___ ___.. I, \..... ~ X. General Characteristics of Transformer Askarel Fluid Appreciation of the following characteristics, as given in the IEEE Guide, leads to undei standing the reasons for selecting dielectric breakdown voltage and moisture as the prime practical tests to judge ii><: quality of transformer askarel fluid. Also, due to these characteristics the power factor of transformer askarel will be normally much hiyhet than the corresponding values for mineral oil. In comparison to mineral insulating oil, askarel <9 a rtlativ-ly polar mafeital; i.e., its molecules are dipoles, free to rotate around tnerr axes rtj tesponsive to orientation by electrical forces. Askarel alsoraxhtbits . much higher dielectric constant and capacitance than insulating oil, j**d these differences most be kept m mind when interpreting "Ifctrical test data. Uocause n is relatively pof.n, and possesses high solvency power, jskarel b much mote electrically sensitive than mineral oil to traces of rxtrancuus soluble polar materials, and consequently the rhoicc of HONS 07475^ 1 conxliuctional material* destined tor use tn askarel is very critical. This Sensitivity '* reflected in lie power factor and resistivity (specific resistance) of the askatel. It it important to note th.itj with the exception of water, the dielectric breakdown voltaic of askajol is not generally adversely affected by many of the soluble polar materials to which its powci factor and resistivity (specific resistance) arc so sensitive, lit fact, the dielectric breakdown voltage of ask<aef is somewhat greater than that of insulating oil. Therefore, thfc values assigned these dielectric fluids in newly supplied transformer* aie 30 KV min. and 2(5 KV mm., respectively. As with insulating oil, askarel must be kept dry. It can pick op moisture from exposuie to humid atmosphere. Under similar conditions of exposure, o',l:arcl can pick!up nearly twice as much moisture when measured on a parts per million weight basis. XI. Sampling Transforrrior Asknrol Flint) The following precautions about sampling arc quoted from the IECE Guide. "Representative samples, whether of the complete contents or only parts thereof, are extremely important from the standpoint of evaluation of the quality c>4 the product sampled. Obviously careless sampling procedure or contamination in the sampling equipment will result in a sample that is not (truly representative. This generally leads to erroneous conclusions concerning nudity and incurs Ic's of time, effort, and expense involved in secunrg, transporting, and testing the sample, ft is stiongly rccorjnmenried that all of the procodures and precautions outlined in the j latest revision of ASTM D 923 (Sampling Electrical Insulating Liquids) be followed. "Because ol Ihe high sncgihc gravity (relative density) of a>Karel (greater than 1), water and tome other impurities are mcM bkefy to be found at or near the surface.;! he top sample, therefore, is considered to represent the worst condition.'' XII. Evaluation of Askaj'el Received in New Equipment Some users of askarel equipment find it desirable to make "as received tests" on all equipment. It is quite common to use the dielectric breakdown voltage test ar.-J visual appearance as the most significant tft*l. If suitable equipment and pained personnel arc available additional infoi matron muylbe obtained horn the power factor, color, and moisture content tests. In sampling askarel contained in apparatus extreme care must be exercised in order to obtain a representative sample. ASTM Method D 923 should be followed. New equipment with askaiej exhibiting the following characteristics is considered acceptable: : Dielectric Breakdown Voltage Color Condition Visual Water Content Power Factor at 25* C 3f)KVmin. 3 )0 max. (Straw color) C ear 3!i ppm max. *! ASTM Methods D 877 D2129 D 1702 D 1533 D 924, D 150 'The power factor pf askarel taken from new transformers, reactors end accessory equipment can reflect the presence of moisture, dissolved polar compounds, or other contaminants and may vary with the typif of equipment from which the sample was taken due to the different ratio* of lipuid-to-soliu insulation and to the high solvency 4wcr ol the askarel. Given on acceptable water content and dielectric breakdown voltage of Ihe askarel as indicated above, a high power factor seldom impairs the serviceability of the ^skatel within rather broad limits and is OS) MONS 074753 indicative ol the degicc ol extraneous soluble polar materials present. Recognizing the possibility of a wide range of power factors being recorded for askarel m new equipment, it is difficult to establish a Single limit winch would be acceptable to both suppliers and usets for all applications. However, as a bioad guide, power fai tors up to about 10% at 2b'Cand GO cycles per second (hertz) do not m general indicate any abnormal contamination providing that the Other ciiten.i (wal*:< content, dictectnc bicakdov.'n voh.tge, etc.) are met. Much higher power factors may indicate cxuisivo contamination or the misapplication of the solid materials used m manufactuic in contact with the askarel and should tie investigated. XIII, Dielectric Breakdown Volin:;!* -- Moisturo Relationship 1 he diclccti is biuvkdo.vn voltage ol ask<u) is inghly sensitive to excess moisture; not sensitive to ordinary dissolved polar material While the dielectric breakdown voilcgc can also b- lowered by severe arcing, .isk.iiel turns notieibh' bhirk m Inr, panic!.!:, nf sooty carbon flr.itirg in it if uitany has incurred. Then the ti ansi-innur shoo'd he rcpjnecl ant! the askarel replaced. If the dielectric breakdown voltage is checked periodically and decreases significantly - this indicates moisture pick-up, areme, or both. When the diclectiic breakdown voltage has dropped to 20 KV or less, an analysis for water is necessary. H water is found in excess of 40 ppm ol room temperatu; j, its source should be located and corrections nv.de. When the moisture content approaches 125 ppm (saturation level at room temperature), the dielectric breakriuwn voltage of askarel drops below the value required lot cilicicnt (mulcting, Ttic moisture content should not !>* allowed to rise c-ver 70 sampled jt on-'ititn ^ temperature. If the mci-.turc foment is found to be m a sabik.c.:nry r;,ivi. ?r,d the rfi.'li'v *.i i*' !ir u 11 own '-olw is iow, the transformer manufacturer should be consulted. Table IV shows the relationship of dielectric breakdown voltage vs. moisture and Table V indicates the approximate water solubility limits in askarel and mineral oil. Table IV Relation of Dielectric Drerkdown Voltage to Amount of Dissolved Water in Askarel and Mineral Oil Water Content (PPM) Breakdown Voltage (ASTM D877I Askarel Mineral Oil 0 70 KV 50 KV 20 55 39 40 47 30 60 -10 26 B0 38 22 110 10 5 HOMS 074754 Table V Approximate Solubility of Water in Transformer Askarc) and Mineral Oil . Amount of Water (PPM) Dissolved C, Askarel Mmcial Oil 30 22 20 -4 10 14 0 32 10 60 20 68 30 86 40 104 8 16 28 41 65 94 , 128 170 ' 8 10 13 20 33 58 85 130 XIV. Turbidity .. . may be the visual sign of ^dissolved water, or may indicate din. Cloudiness may also icsult It am cold piecipitation of iin teurphenyl "scavenger" that was used in the earlier Pyranol transformers. This scavenger begins to come out 0f solution around 1ST above zero. To redissolve it requires heating to [150-200' F and agitation. High dielectric breakdown voltage will quickly indicate that any turbidity present is not moistute; that the insulating efficiency of the askarel is still excellent. However, if the dielectric strength is below 26 KV, moisture should be deter him id. using the Ksrl Fischer method (ASTM D1533-60). The (tiefcctric breakdown volume test for sskarei serves primarily as an indicator for moisture, it is by tpr the must important maintenance rest lor transformer askorcl. 1 XV. Chock Points for Maintaining Askarol Insulation A. General Considerations: Modern askarel Ir.msfotmeh witf> welded construction or silicone or Viton* gaskets (harjd hole-cover, switch and terminal compartment covers) and with properly constructed bushings require little maintenance. With properly constructed transformers, annual or! semi-annual visual inspection and dielectric breakdown voltage test of the askarcl fluid should suffice for routine znaintjmancc checking over many years of sorvice. However, many ackarel units were installed in the early 1930s -- before the development of some of the better modern gasketing materials and boforo improved designs were developed for sealing out moisture. Such early uhits should be, and can be, modernized. Leaky or deteriorated gaskets should Pe replaced. If the askarel has become contaminated, it should be reconditioned. At the same time, a general clean up of flic unit and possible refimshmg may be desirable. If it is not convenient to take an old transformer out of service for genoral repairs, leaky gaskets can be sealed temporarily by painting over the leaky area with epqxy cement. A survey of users indicate* a good number of early-built askarel transformers (over 20 yearsj old! an; kept <n continuous service in critical installations by the following steps (instead of modernization). Tire operating units are equipped with compound pressure gauges for reading pressure above and below atmospheric. Positive 'Trademark of . I. DuPont DrNemoijrs a, Company, inc. ------------------------------- 1--------------------------------------------- 0NS 074755 pressure is maintained on the shell by introducing mtronen at ? lo 3 pounds above atmospheric. Regular workmen in the area daily record the temperature and pressure. If a sudden pressure drop is noted more nitrogen is introduced and the gospels are checked tor leaks with soap solution. Leaks arc sealed by applying epoxy cement. B. Modern Sealing Procedures: Transformer purchase! s should specify the following modern techniques for sealing: 1. Welding Constiuclion: Covers, radiator connections, switch and terminal housings, instrument connections, etc. should be welded. 7. Uurhing Connections: A number of bushings have been developed to obtain a proper seal for the ekctnc.il connection through the tank wali. They arc clashed as follows: 1) Welded Type - (Bushing flange welded to lank wall) a. Cast icsin bushing with s molded seal to the bushino stud and external stainless steel or copper flange*. b. Rolled flange bushing with the nutal to loicelatn seal at the cap and flange made by being toll, d into grooves in the porcelain over silicone runber rings. The sval between the cap and stud is m..dc by weldirg. c. Porcelain or glass bushings with metal to glass or met;l to poreuiam svds. 2) Bolted Type | Sol ted to tank wall) a. Cast resin bushincs wun either cast or metal flanges containing recess :d y :skct gicoves. b. Porcelain or glass niiihmgs with flanges containing recessed o'uovcs or psket stop. The gaskets rney be either of in lenguh'r or circular cro*s section, usually Vi inch thick. Bushniy . with recessed grooves ce suitable to use with cork, cork-nitrile rubber combinations or nitrile rubber as well as g3sket m.neiuls such as silicone or Viton. 3. Small Size Connections; When not possible to weld, small size connection seals should be rncue with Flexitallic* stainless steel rings. The sui faces must be machined and parallel. The fillci between the steel laminations ol the Flexitallic ring should be either silicone or Viton. 4. Gaskets for Hand HoIp Covers: Modern design specified silicone gaskets. Such gnd.cts must Li; retained >n a groove. The groove picferably is machined into the flange or cover. However, it can also be formed by welding concentric steel strips to the fiance or the cover. Generally the gaskets should be 5/16 to 1/2 in. thick for covers, depending on the depth of the groove or stop. A rectangular cross section is usually used. The silicone material should be Oow Corning No. 50 Silastic** or equivalent. This is a low compression set material. For best scaling 20-25% compression is recommended, with ample clearance in the groove ot stop to allow for this compression, No cement is requited. With reasonable care the gasket is removable without damage and is reuseablc. Silastic 50 is slightly swelled by askarc! which contributes to the tightness of the seal. It is not deteriorated bv askarcl llutd or vapois. It resists weathering and it is thermally stable and Tidileifiiwk ot riexii.ifttc IjlrtVol'Company Trademark of Dow Coming ni MOMS G74756 flexible at oil operating temperatures. It is an excellent moisture bamci. NOTE: Oow Coming, Midland, Michigan will supply a list of Silastic 50 gasket fabricators to nil transformer manufactuirrs or users. They will also furnish technical data. See Appendix<\ ! Seals, Properties and Procurements. The Older Scaling Anangemonts: The older type gaskets chmist of ehhei cork or ror k-nitrile rubber combinations or straight hitnle rubber. 1. Coik-Niltilo Combinations: Covert tor the main tank, hand-holes, switch J)nd terminal chambers, n-liof diaphrams, etc., are hold in pljjre by stuns welded to the fl.-.ngp or by bolts. The ('J'.k'-ts arc cut wnh openings ami pieced over the bolts. Olt.-n Sheila; I Wo: bughouse Stylo No. 1150*119, or General Electric Company's Glyptal* 1276) is used to cement the co.k to ho Manges. The following i, recommended for sealing with the cotk nitrile rubbci combinations: Use Airnstrong NC-757 corknitrile material or equivalent. The gasket can be cut horn a sinale sheet or by scarfing strip; of the material. A qunvenient method for joining strip, is to make a Keystone Typ' joint. For this purpose, Wesiir.yhousc, Sharon, I'ennsylvnnip, offers thoir gasket cutter Style No. 328 B514 G01, {about S'lol The joints - and ah.b the gasket - should be cemented to the flonyc, using one of |hu above cemonts. Excess cement should not be allowed to rejtcli the interior of the transformer. After installatrcn add holtmo. the outside edge of the casket should ue coated tlwrougnly vvitn epoxy remen; to inn ease weathet resistance. , This epoxy content is s paste to which a curing catalyst is added immediately l^cfore use. Typical are: a. Epoxy Paich Kit # l-C Hysol Corporation, Glean, New York b. Scotchcast* * F^erin #4 Minnesota Mining i< Manufacturing Company St. Paul, Minnesota C. Adhesive A-1 ajtd Activator Typo B Armstrong Products Company Argonne RoadJw.irsaw, Indiana d. Adhesive Oubo-1, Synthetics Organic Company, Cleveland, Ohi^i, used with cctivator diethylene triamine {Catlxdc and Carbon Chemical Company) 2. Straight Nitrile Rubber: When straight nitrile rubber was originally used, invarjiably the gasket was recessed in a groove. This was to preventjgasket flow and to protect the material against excessive compression. Although this type seal was not cemented, the nitrile rubber g.nkct is not reuscable. Since grooves or stj>p$ have already been provided for the nitrile rubber seal, Silastic 50 can be easily substituted and is recommended. This Conforms with modern practice. XVI. Periodic Fluid Inspection and What Checkpoints Mean On a regular schedule - at six nine, oi twelve-month intervals -- make t simple visual m>p< chon of ypur o-.kaicl insulation and run a dielectric breakdown voltage chock. Mf.idemark pi Genixol h l< rtnc Company Tiaopmitrk ol Minnpsniu Mining fii MJmi<<*ctunny Company r-' HONS 0 74 75 7 I A. Visual Inspection: Askarel is a clear, laintyoMow lipind. Alter lunn term me this color may gindually intensify to light brown. The fluid should remain clear and free from turbidity o cloudiness. Any color change - such as to a green, u-d or blue cast - indiotes extraction of impurities (color materials) from the solid msuLiimn. If a distinct foreign color pick up is noted, check the complete range of electrical cliarjctcnstics and notify the transformer maker, blackening of the ask.vcl may indicate an arcing condition. Other color changes alone are not danger signals since the dielectric breakdown voltage is not likely to be impaired. B. Dielectric Breakdown Voltage If the dielectric breakdown volicg.- hjs decreased significantly from the last inspection, or if it has gradually decreased b>-lcw 26 KV range (at 2bAC) - RUN A CHECK FOR MOISTURE. Use ASTM DT533 (Karl Fischer Method). The dielectric breakdown volt.*c.a of udt.irel is tit major indicator to the operating eltOfmcy o< your licuid n.yjbiion. de.iris the visual inspection tests, dielectric ttej.ihlotvii volt-ve is ih- only test necessary to run on c. routine basis. V.'ell-seJtd aikjrel transformers have service recotds of 25 to 30 years on the original askarci. XVII. Inrpsciion Checklist 1. If askarci is clear -- even though darkened to light brown, ha? no sediment or tuibidity, nes dHecuic bieakdawn volur.-i <ur 2b KV - give it the inspection "GK". 2. If askarel is clear, but has foreign color of blue, green, red ... d is "extracting color" from internal materials. 1 hs is net. ol it: a-lf. an opcrrtiryi hazard when the r.' eicrtnc l.-ejM)e.vti volt-ij:1 st.-y*. over 26 KV and moisture remains low. Hovv-.-ver, mis rare occur: nee calls for cheeking into the Condition of ;i;c int-.ric c.-n.'iuruon and consuliinj the transforms: r.iikcr. However, when t,,rr;p!.ng the fluid care should to U\cn to avoid vetting color >mo the askarel ftom paint that may be inside or outside of the s. mple valve. 3. If the moisture content is found to be above 70 ppm at oo'jrabnq temperature, then sampling should be done at more frequent intervals to establish a possible trend, particularly on outdoor installations. 4. t< askarel is clear, but dielectric breakdown voltage drops to 22 or lower KV, and moisture rises over 00 ppm when sampled at operating temperature ... the askarel is ready for simple "refining", tf the moisture is near the saturation level (about 125 ppm at room temperature) a thorough inspection should be made for water droplets in the transformer tank, and even for "globules" of water (looting on the askarci stnfacc. If found, the transformer manufacturer should be consulted for reconditioning both the transformci and the fluid. 6. If askarel is dark brown to black, if black particles of carbon arc seen, and dielectric strength is low .. . the askarel has been hroken down by arcing. It cannot be refined and should be removed and incinerated under proper conditions. (Sec ANSI Committee C107 report on Use and Disposal of Askarci and Askarci Soaked Materials. New York. New York 1U0lJ$. IS30 Srofldw*y, If any of these five simple inspection tests appear out of the ordinaly oi die relationship between appearance and test values is abnormal, contact your tiansloimer supplier for a complete analysis. Whenever a sample is to be shipped to Monsanto, please follow the directions shown under: "SAMPLING ASKAREL". MONS 07V758 XVIII. Contamination in Transformers Moisture, particulate niiittci and arc'-d decomposition products arw know'll to bo serious contaminating influences on transformer askarel. The power factor test normal! V used for the detection of contamination in nUnorsi oi' fiUvd uanslol rncS is of little use for this purpose in askarel tilled tMnsloimcrs, due to the extiemc effect of extraneous soluble polar materials. This; increase in power factor as illustrated in Table VI has no advarse clfecjt on dielectric breakdown voltage. Table VI Effect of Commoh Insulation Materials on Power Factor and Dielectric Strength (Heat Aged SCxfours in Askarel at 100X.) Material Immersed Askarel After Exposure Power V actor, Percent nt 60 eye., 100C Dielectric Strength 25`C. None (control) 1.0 35 KV Black varnished cloth 850 42 Copper 1.5 40 Prvbod 2.0 37 Manila paper 1.5 39 Phenol formaldehyde resins 1.6 41 Shellac 6.0 36 Iron i 5.0 33 Synthetic rubber 70.0 30 -------------------------------------------1---------------------------------------------------------------- Similarly, trace contaminants from commonly used construction materials can lower the volume-resistivity of oskaiel, without affecting its dielectric breakdown vohfne. This h shown in Table VII. * , Table VII ! Effect of Cojmmon Ir. ulaticn Materials on Vo!ur()u Resistivity of Askarel | Sample Volume Resistivity x 109 ohnvcm (at IQO'C.,500 Volts DC.. 0.1" gap) 1. New askarel before heat aging 2,000 2. New askarel after heat ayihg 96 hours at 10CTC 1.900 9. After heat aging with 1 tu. inch specimens of: a. Phenolic resin tap changer material 1,200 b. Paper , 750 c. Grade A pressboard (tah| 500 d. Grade A pressboard Igrpy) i . Grade A prtssboord, laminated strip i f. Cotton wrapping 1 500 400 300 g.Glyptal 1276 cement, tjured 48 hrs. at 110*C 100 While trace contamination jeasily lowers volume resistivity from high levels, it is important to note that heavy contamination (as when arced) does not lower the resistivity below the order of 10 ohm-cm. at 100C. * The different behavior of aikare! vs. mineral oil in these respects can be summarized as follows: High power factor ehd low volume resistivity in transformer mineral oils are comnionly regarded as "danger signals" that the oil has deteriorated fnd broken down chemically or excessive moisture is present. > This is NOT TRUE of askarel liquid insulation unless the dielectric breakdown voltage is Ipw or the moisture content is high. M HONS 074759 rX !\ Manufactures of aikarel type transformers point out that it is rju'te well known that askarcl transformers with initial power factor of the askarcl fluid in excess of 50% at room temperature and 60 H t are rwino satisfactory service life. However, there needs to he assurance that both dielectric breakdown volume and moisture are at s.insfactoiy levels and do not show adverse trends. __ f> 5*SS XIX. ASTM'-iVlethocI For Investigating The Compatibility of Transformer Insulation and Construction Materiel* in Ask3rel$ ., This method* uses the change of electrical and/or chemic .1 characteristics o< transforms askaiel resulting liom its controlled exposure to insulation and construction materials, in ordai to evaluate their immediate major "contamination" effect on the asxeiel Nurd. Delayed or long time contamination effects may not be detected The method also utilizes various physical tests on tire insulation and construction materials after controlled exposure to the osk.'rsl to determine the compatibility of these materials with transformer askarcl. Properly proporrom-d specimens of the insulation or structural materials ate immersed in refined askatel for 16S hours at 100 + 1'C in a forced draft ovnn Changes in electrical and chemical properties of the iransfotmer askorel are compared against a control sample of the askaiel treated in the same manner, in absence of the test specimens. Dissipation factor (ASTM D 924) change is one of the criteria used. The askarel fluid is refined by absorptive treatment to a dissipation factor level of 0.05 max a* 100'C and CU Hz and 0.0t max. at JiC nnc* CO Hi. Corresponding values of the askarcl fluid after heating 1G3 hours at 100'C in absence n.` a test specimen are 0.075 and 0.02 respectively. The maximum dissipation factor levels surnrstecJ for the -s>aiel after healing in presence cl the test specimen are 0.20 at 1G0C and 6u Hz and 0.04 at 2buC and CO Hz. XX. Refining Asknrcl for Rcv?*i A. Filtering Through Dry Blotter Paper to Remove Moisture and Extraneous Particles: Most operators prefer portable refining apparatus, such as a plate press fitted with a dolly, available from Sparkler, Mundelein, Illinois or General Electric Company, Pittsfield. Massachusetts; or the earthen cartridge filter type available from Industrial Filter Corporation, Lebanon. Indiana. Filter paper liners for the plate press are available from Carl Schleicher and Schuell Company, Keane, New Hampshire and manufacturers of filter [tresses listed above. The filter paper must be dried immediately before use. For best results, spread the paper for maximum surface exposure in a hot air circulating oven and heat it for 4 to 6 hours at 110"C. |prec/?^ T/CtfS. Circulate the askarcl hot (but not over 4(TC) through the filter \ fitted with the dry paper liners. After filtration the dielectric breakdown voltage of the askartl should be 35 KV minimum. . -Chack---- jpj| Mloou PrevntH'iermvFiltering should not be done when the relative humidity exceeds 75%. Any flexible hoses and gaskets on the refining equipment should be lined with or made of materials that will not be softened by contact with askarcl fluid. (Materials lined with Silicone, Viton or Teflon* or flexible metal materials are suitable.) S' iTTpTnepsrtit piErasricr t/; ... Tracfonieik o< E. I Dul'oni DcNemouu & Company, tnc. HONS 074760 iTable Vill Guide to Rate if Dissolved Water Removal By filtering Askarcl Through a Paper Press Water in Askatel , PPM 115 35 22 18 12 10 to T/ic AiUS I <)-' C ic1. I - m*- Disposal ol Solid Wastes^ /-~c ThoANSIGuiou- sutesj-th>{, "AH Sohd tve-.t*s`whi.'b havr b -<Vi 'i saturated with askarcl-phuuld he (iirposerl oi by the following' fprocoduro; .; *1.---The - saturated wastes should be pl'x<;d inro leakproof containers and tralirported to a su; wviad dry landfill site meeting State requirements. Alternatively, they eery'be disposed of by Incineration In Srete-approvcd facilities./ ^ ,2..-' Solid absocbents used tor spills can bo disposed cV uncontained In th^ supervised dry ianiJtill sito; namperyto the site should |be in closed containers. Alu:inativ-.jly>< Incineration enn bo used in accordance with par. U_Joo.. Section 4'for facilities)." 5 . I * G tl?1 Solid Insulation Requiring Drying: If the solid insulation cif tho transformer requires drying, consult the transformer maiuificurer o an apparatus service shop, as in such ca*e oven drying i$.|piefcrrc-J. Earth Treatment tor Maximum Improvement of Power rector and Volume Resistivity: We question whether bumping end filtering the fluid solely to Chieve e change in ppwer factor or volume resistivity alone is justified in today's ecological climate regarding PCl3s. IVe recommend that in tpese situations the original transformer manufacturer be contorted. 1. Procedure: . | The eskerel liquid should be relatively diy prior to the following earth Itl ration. As e coating on he fitter poper surface use finely divided Attapoigus- cloy >r Fuller's earth dried and activated by heating for 12 ho in at 300-350 F immediately prior to use. The amount of c irth usod should be 0.1 to 0.2 percent by weight on the weight of the askarcl to be treated. Askarcl weighs about 12.5^ pounds per gallon. To daposit the eafth evenly, stir one-third of the earth with a small portion of askarcl in a clean container. Pump the mixture through the filter and follow svith two more one-third portion?. Then circulate askarcl taken from near the lop of the transformer, pass it warm (not over 55C) through the earth-coated filter and feed back through the bottom transformer outlet. Continue circulation until the fluid is clear andjtcst shows that the electrical properties are fully restored. 2. Effect of Earth orK Removal ol Scavengers Only slight and insignificant loss by selective absorption of tin tetraphenyl ahd epoxides occurs when askarcl is relined by treatment witn 0.1 to 0.2 percent by weight of catih. To remove significa)pt amounts of the scavengers rcouires repetitious treatn} nt with much lair,or amounts of earth. qti -ciiim-d 1`lii-i'i * >ii nno C. h Vi: ulr rtONS 074761 Table IX Approximate Relationship Showing the Insignificant Effect of Power Factor and Volume-Resistivity on Dielectric Breakdown Volligc of Transformer Askarel Power Factor (60 eye.) Iqtrc 25^C Volume Resistivity x 10* ohm-cm (at 10(TC. 500 Volfs _octolraiiL Breakdown Volli-je 2j>"C, 0.1" gap 2% 55% 15% 20-25% 40-50% 0.05% 0.1% 0 7% 2.0% - 1500 500 100 60-70 25 35 KV 35 35 35 35 XXI. Ctssning Arced Transformots If a unit has atced so that the askarel is no lonoer fit for use, a thorough cleaning of the unit is necessary befoic- refilling with n**w askarel insulation and returning it to service*. Follow this procedure' A. Drain out all dark, carbon-contaminatcd askarel. Arranca to have the setkp fluid incinerated under proper conditions. (See ANSI Committee C107 report.) B. Carefully brush carbon deposits from internal parts and insulation, using a soft bristle brush making sure that insulation is not damaged. C. Flush thoroughly using new askarel - not an oil, not a cleaning solvent. D. Flush a second time with fresh askziel; dram; then fill to the proper level with new askarel. E. Energize transformer to warm the fluid for 24 to 48 hours; then circulate the askarel through a litter, returning it to the unit filtered and ready for use. 'This niiumoj that the cause ol arcing hot been established and corrections made. When severe areing occurs. mor repairs ' usually neectiary end Hi* unit rebuilt. This procedure can he applied for flushing out the repaired units. XXII. Sampling Askarel Take a sample as close to the top oMhc liquid surface as possible. Many large askarel transformers have a built m sampling tube near the surface for convenient sampling. Then, to make sure that your sample truly represents your askarel insulation, take another sample from the bottom. If additional sampling tube connections are contrived on the valves for easier sampling, make the tubes of clean glass, stainless steel, aluminum or tin for rigid types; and silicone, or Viton or Teflon tubing foi flexible types. Use NEW containers for the askarel sample. A new and thoroughly pre dried,small-mouth quart glass bottle fitted with a Bakehte* screw cap with aluminum or tin cap liner is recommended for quick, on site testing. (If complete analysis is to be made, a 5-pmt size sample is required.) Be sure that the new bottle docs not stand open to collect dust or moisture. Rinse the sample bottle and cap lining two or three times with askarel from the transformer, then till it. If the sample will be tested promptly, a clear glass bottle can be used. If sample is to be stored indefinitely, use an amber glass bottle or wrap clear glass with aluminum foil. A. Select a dry day. Do not sample insulation on a warm, moist day when humidity exceeds 75%. and . . . Xv 'Trademark of Union Carb>d Corporation HONS 074762 B Make sure that the askarel is at least as warm as the surrounding air. (Cold liquids can cqndensc moisture from humid air.) C, When sampling askarel from transformers, it is best to take the sample when the unit is warm and operating at average or maximum load, especially lor a check on moisture as reflected by a dielectric breakdown voltage test. Sampling the warm askarel more truly represents it* condition during operation. Experience shows tha^ water will migrate (rum a translormci's solid insulation to the psknrel liquid and vice versa, depending on im|eraiurc. Therefore, when the transformer is hot, lire moisture is most likely to be foijmd in the liquid. This accounts largely lor periodic variations in dielectric breakdown voltage, For example, a relatively high dielcctiib bieakdown voltage may he found during winter months and a rjelativcly low dielectric bieakdown voltage during the summer months on samples taken from the same unit. When testing has beeh completed, the remainder of the fluid sample should be destroyed by high temperature incineration . described in Section Vl|l. I i r: i u> t..:.. i i i ! I IB I. Introduction High voltage leads arc usually connected to askarel or mineral el-filled A TT network transformers and power centers through terminal clumbers and switches. In some eases terminal chambers ate not uv.-d, and the high voltage loads are connected directly to the switch terminals. Tl.<*y moy be filled with either askarel or mineral oil. Switches are usually rotary or drum typs fitted with a revolving block end porcelain unit as the t'.1 incli-.il clt::n'jit\in:uHirr} ,m thm: ;>h.se service. l* A;.l:;;rr* trairtfurmets with rthTkrd '..vile!'"* h.v.\' been in use for about 30 yeais. When they were first intioJutad, the availability ol msulat-nq W *.V - i kii and gasketing materials was rather limited and even the best materials at the time hud no service history. As a result, inadequate gasketing materials such as cork, nitrile rubber, and nttnle iuhncrand-co'k particles were used. While satisfactory for a limited p?fiod of time, these materials cannot be detrended upon for the expected lorg life of the equipment. The terminal chumisur is usually above or below the twitch compufrnont and separtried by a stc;! wall through which th; bushings are inserted. When bushing. aie properly selected and correctly installed, there is no leckacc from one compartment to the other. With poor bushing seals, and the ten-final cnamber {.hove the s.vitch, potting compounds or cable oil can seep into the askarel. When the terminal chamber is below Ihe switch, askarel tan dram into the terminal chamber. II. Sourcss of Contamination There are three possible sources of contamination fur askarel in switches and terminal chambers; they rank in this order of frequency: (1) water entering through poor pickets; (2) decomposition products from arcing when switch is used to break magnetizing current; (3) entrance of potheed or cable compounds through leaky bushing seals. Unlike an askarel transformer where the amount of contaminant is likely to be very small (piobably only trace amounts) in relation to the volume of askarel fluid - in switches or terminal chambers with faulty seals, the amount of contamination can be relatively large. Experience has shown that, based on the number of installed askarel-switch units, the percentage of failures is extremely small. When investigated, it has been found that most failures originate m the switch chamber. Water is the chief source of contamination. However, heavy contamination of askarel with petrolatum and asphalt material, due to leakage, have caused a few failures. Petrolatum is used frequently for filling terminal chambers. When cither cable oil or petrolatum seeps into askarel, no great harm results. The fire resistance will be somewhat decreased and power factor of the askarel will increase with an accompanying drop in resistivity. While highly undesirable, it is doubtful that failure of the unit results. Where asphaltic compounds are used m place of petrolatum, the danger is increased somewhat because asphaltic contamination moy cause excessively high dielectric losses in the askarel. When the terminal chamber is below the switch chamber, the potting compound can be contaminated by askarel if the bushing seals are fcaky. This is undesirable because the askarel will increase the power factor and conductivity of the potting compound or cable oil and dtsvelop heal from die'cctnc loss. II this mixture is drawn into the cdtlc MOMS 074764 nnrt insulation, a cable failure is likely. This again emphasizes the impoi tance of tight bushing Assemblies. III. Scoling Switches and Terminal Chamber* Proper bushing construction^ use of Silastic seals and welding wherever possible is highly desirable (as coveted in Section A). Where an elastomeric seal is to bo lused in contact with both askarcl and petroleum oil, OuPont's Vitojn is suggested. For now equipment the user should specify these modern sealing arrangements to keep out contaminants and minimize maintenance. IV. Atkarel Used Under ihlild Aruinv Conditions Tha IEEE Guide (or Transformer Askarcl calls attention to the following: "Askarcl is used, to sonic extent, in apparatus where it is subjected to light intcimitlimt arcing, such as in sett-contained induction regulators, when* operating switches .no continually producing Slight arcs, in transformer deenergizing switches, etc. Under normal conditions, dultorioiation of the askarcl is very slight. However, improperly adjusted or ti3i.:uiv*; `w.tciv.-s in this type of apparatus cm produce excessive and prolonged arcing and accelerated deterioration of the askarel. It i$ recommended that when askarcl is used wider these conditions, checks of the liquid, especially for moisture end dielectric breakdown voltage made more fscquontly than, wnen it is used only as a cooling and insulating fluid. Dctnrjioraticn of this type is indicated by a blackening of the Imuid. h can usually be reconditioned as previously described. . Sped.! attention should be given to maintaining the scavenger at the appropriate concentration." V. Maintenance for Askjirel Filkd Switches A. Switches usr;J foi grounding after power source has been de-energirod wifi not undergo .'ting. B. Switchos interrupting magnetizing current will be subject to arcing; the amount df decomposition will depend on power interrupted, time and frequency of operation. As a genera) rule, tho liquid should be chicked after l> to 10 operations. 1. On newly initafleijl switches, check the askarel at 3. 6 and 12 month intervals; il found satisfactory. check cnee annually thereafter. With (itopei attention to the gasketing of covers and bushings, experience will probably indicate that less frequent inspection is wairanted. 2. Check askarel tor: a. Dioloctiic breakdown voltage (ASTM 0877): It should be 26 KV rr)inimum. If dielectric breakdown voltage is low, confirm presence of water by Karl Fischer method ASTM 0-1&b3. Filter to remove nroisture. Dielectric strength should then be 30 KV minimum. b. Presence of carbon from arcing: Fluid should be relatively freje of carbon If badly arced and very black, replace flukj. If only minute amounts of carbon are present, filtrltron is recommended. Check power factor of liquid (should not be over 8% at 25*0 and 60 cycles). Flush out switch chamber with seveial gallons of fresh askarel before refilling. 3. If there is discoloration, high power factor, detectable change in specific gravity or refractive index, or il fluid flashes below 7&&T-, there is a Jpossibility of seepage of potting compound into the switch compartment. In this case, correct any leaky bushing seals with proper replacements and fill with new askarel. 4. If teiminal chamber is below switch, check potting compound for presence of askarcl (can usually be detected by ndor or by afs increase in specific gravity). If askarel is present, coircct any leaky bushing seals with propor replocoments, and renew compounds. 5. Examine cover gajskets visually. Deterioration can be detected by swelling and cracking of the exposed edge. In cases of severe deterioration, liquid seepage is usually prcr.cnt. 6. Check for leakage at (tacking gland of switching shaft. If leaking, repack with a Silastic ring type gasket. VI. Askaiul Under Excessive Temperature or Fault Condit'ons The lEEt Guide also points out that, "Chlorobeivenes used in transformer askerefs begin to boil at temperatures of about 205*C, under atmospheric conditions. H the material is heated to such high temperatuie in a sealed system, pressure develops. Pressure will also develop in the system if the askarel is arced sufficiently to generate copious hydrogen chloride gas. "Therefore, it is recommended that wherever possible, sealed askarel filled equipment ba provided with pi assure iehpf devices. Those clevirf'*: must he l.-nr-e enough to pinviu.* immediate rclivf at a definite pressure, and lo piovent blither build up of pr e^tnc if decomposition continues. It must be remembered that the picscnic oi devices of this *.';rt doe; not necrssdniy preclude the rupturing of containing vessels, since pressure btiiid up c.sit be extremely rapid under violent arcing conditions." MGNS 074766 (tan :D S2T\/iz33 L"i linT^oi^n^n*/; 0r^.7fvu "<*> Awct*:-lcA LA v G>>jii Li Ci~j ; 1 ^T3> i ;7';`T'v 'rrr>, ] / !'rriri`i'fnflw JU'w' j.i. Li *Aa^, i_iiJ aw LL'L-/ < i. t vlJj. Trarnformot men not wishing to make their own fluid analyses can obtain the service from Monsanto. Simply contact Monsanto and specify what analyses art wanted. You will be sent the proper-sized, clean sample container, fitted with a proper labvl. When you rocaivo this, carefully lake your sample (following the procedure for sampling in this guide) Send the contaiiwr to Monsanto's laboratory. Charges listed include sample containevshippingr-handlmgand laboratory costs. T;i < fkoc-t in 1, lO^f, /tru, yV l e _ Typos of Analyses Available Analysis 1) 1 c h't >'-t > .9 >'<*' * ROUTINE MAINTENANCE CHECK Total Charge: -S?WK*-- 4ot?* W To determine (he general condition of the fluid i*nd find whether further ;<w**y-h is nr*cc.*ry, (nnc-qm*rt sjuvmh* required) Properties Tested : Dielectric Breakdown Voltaic Color artd Condition Moisture You will be notified of the rjcsults of this test. If further testing is indicated, and you want a complete analysis, you will be sent a flve-pmt sample container. T^is sample will be used for the following series of tests: Analysis 2) COMPLETE ANALYSIS . .. Total Charge: SF.&.00- f7<>'<'T 0) To determine the extent if fluid contamination, (2) earth refinement to determine what degree of restoration of electrical and insulating properties is possib|e, (3) chock test to see how the fluid responded to earth treatment. ) Complete Analysis: to det^rmine the extent of contamination Properties Tcited Free Chlorides Color and Condition Acidity Specific Gravity Dielectric Breakdown Voltage Refractive Index Power Factor, Dielectric Constant, ar.d Resistivity Water b) Earth Refinement Response: Consists of treatment for 2.5 hours at 50-60X2. with 0.1 to 0.2 percent by weight of properly conditioned Attapulgus clay and then filtration through dry filter paper. c) Analysis After LaboratorylEarth Refinement: Properties Tested Acidity Refractive Index Dielectric Breakdown Voltage Water Power Factor, Dielectric Constant, and Resistivity Free Chlorides You will be notified of lhc results of this test series on your sample. Than after refining your entire transformer fluid fill you can check on the results by requesting the following analysis: Analytic 31 , ANALYSIS AFTER EARTHREFINEMENT Total Charye: S8S-S0- rn -r-r <- ' >- (This charge will not apply when analyses 1 and 2 have already been made.) To determine whether the entire lot of the askarel fill lesponded to the same oxtont as the laboratory sample, (five pint sample faquir ed) Properties Tested Free Chlorides Color and Condition Acidity Refractive Index Dielectric Breakdown Voltage Water Power Factor, Dielectric Constant, and Resistivity To arrange for the tests described above write to the following address: ` ~ - r ` Wood Monsanlo.Cqmpany 800 North Lindbergh Bled. (Fvj/r/*/ c://'<?< St. Louis, Missouri 63166 Samples to be tested should be clearly mai ked for identification and sent directly to: Monsanto Cbvwuaei Corrjpany } )______ W. G. Krummrich Laboratory ^">rvrrfr wieinw^cti^y.^rS Sdogct, Illinois 62201 Attention: R. Kustcr : MGNS 074767 i \@s I. APPENDIX A Askarel Stability and Composition of Arc Formed Gas: Askarel insulation is one of the most inert. chemically stable heat resistant, non-corrosivl1 liquids known, h will not break down, oxidize or sludge when exposed to air and hinh temperatures, IbOT. or even somewhat higher. Arcing, however, will break down the compound to liberate some hydrogen chloride and small amounts of carton. APPROXIMATE COMPOSITION ARC-FORMED GAS FROM TRANST Cr.MCR ASKAREL BLENDS ASTM TYPES D AND G (INERTEEN 70-30 AND PYKANOL A13R28-3, RESPECTIVELY) Gas carbon monoxide car bon dioxide oxygen inert gases hydror.an chloride (note the absence of phosgene) Amount 0.3% 0.3% 0.G% 1.6% 97.3% This arc-formed QOS frohi ASTM Type D and Type F transformer askarel* is non-flammable and non-combustible. For all practical purposes, the amount of gr-s liberated from askarel under a given set of arcing conditions is about 100 cubic centimeters per kilowatt -second. APPENDIX B________________________________________ ____________ SOLUBILITY OF GAS IN TRANSFORMER ASKARELS ASTM TYPES D AND G Carbon dioxide Air Nitrogen Hydrogen chloride1 Mn absence of scavenger Percent of Gas By Volume Corrected to: 25*C 760 mm OX. 760 mm 2t/C 71% 5.7 6.0 37.8 iotrc 47% 4.9 4.8 50.9 25"C _ 5.8 5.5 10CTC _ 5.0 4.4 APPENDIX C______________________________________________________________________ EFFECT OF TEMPERATURE ON DIELECTRIC BREAKDOWN VOLTAGE OF ASKAREL |Temperature *C -60 -40 -20 0 20 40 60 80 I Dielectric Breakdown Voltage ASTM D877 67 KV 63 57 55 50 50 48 45 HONS 074768 APPENDIX D COMPARISON OF THE APPROXIMATE VISCOSITY IN SAYBOLT UNIVERSAL SECONDS OF TRANSFORMER ASKARELS AND MINERAL OIL Temp. *C -20 6 20 40 60 80 109 Pynnol Airtasn-3 1,000 100 70 46 39 34 30 10-C Mineral Oil 1,000 150 85 49 40 34 30 Inertccn 70 30 2,800 195 85 DO 40 36 33 APPENDIX E THE Imu-iYV OJ: K mO'i rli.rv 7D-'0 AND THAWSFOJ.MEfl PYBAl 'OL AWjS-Z Approx, Density gm/te. jomp. *C 0 20 40 CO i 80 Inertcen 70-30 1.574 1.552 1.529 1.507 1.485 Pyranol A13333-3 1.577 1.555 \ 537 1.510 1. .83 APPENDIX F |; The thermal conductivity value* of transformer Pyrar.ol A12? 30-3 at 27*C and E'C arc 23.2 arj 2G.3 x 10* calories centimeters-', currcet Jc?ntfyrcdcj, second*', respectively. Or, approximately 0.05 5TU per (hr.) fwj. It.) (*F.) per foot. This seme approximation applies to Inerteon 70-30. APPENDIX G__________________________________________________________________________________ Heat Capacity Over the temperature 4artge of 26* to 125*C the specific heat of tiansformer askarel is close to 0.30 calories per gram per dogree. APPENDIX H___________________________________________________________________________________ Coefficient of Ejcpamibn The average coefficient of expansion of transformer askarel over the temperature range 20 to 100*C is0.0007 cc/ccAC.One gallon would increase tp T.056 gallons on heating from 20 to 100*0. APPENDIX I Fire Resistance Atkarels of various Qomf>ositional types are used. Under arcino conditions the gases produced, while consisting of predominantly non-cofnbustible hydrogen chloride can yield varying amounts of combustible gases depending upon the askarel type. Insulation systems Incbrporating these askarels and cellulosic or other organic materials may, when arced, produce n.noous mixtures which are moderately Usmmoblo. As a precaution, such rpscs should be removed from the askarel by bubbling dry nitrogen through the askarel and flushing the gas space with dry nitrogen before any work is performed on the apparatus. DA HONS 0 74 769 APPENDIX J Soals. Propurtios and Procurement Dow Corning CorporationTMidland, Michigan with Districts fit Atlanta, Boston, Chicago, Cleveland, Dallas. Los Angeles, New York City. Washington, D.C. and Toronto has available Bulletin 09-010,August 1962 entitled "Silastic Design Data*'. This list! the gasket fabricators throughout the country from whom the "Silastic 50" gasketing can be purchased in sheet, extrusions or molded shapes. ' Generally, Silastic 50 sheet'goods are stocked by local die cutters, hence, could be generally purchased locally. Usually small quantities ol gaskets are |die cut. II larger quantities are needed, tools are made of the same type used to cut other elastomers. Where the gasket is extruded for fitting into a machined groove or between gasket stops, Dow Corning advises use of a searvtd joint. This joint than cemanted using Dow Coming's Silastic 140 (clear) or iheir RTV 731 (white) materials, which air cura. ; Dow Corning points out that the local "rubber" fabricators purchase the Silastic 50 in billet form. This is worked on a roll mill in preparation for sheeting or extrusion. Then to obtain the desired physical properties the fabricator must ovan cure the Silastic 50 lor 24 hour* at 460"F. SPECIFICATIONS* ASTM 0674 ASTM D412 ASTM D412 ASTM D395 Color Specific Gravity at 77*F Hardness, Shore A. Scale Tensile Strength, psi, min Elongation, percent, min Compression Set after 22 hr$ at 300*F, percent, max White 1.2010.02 45 to 60 800 250 30 `All physical properties pleasured on 0.075 inch thick samples molded 5 minutes at 24PF, and ovan cured 24 hours at 480T. A..P.P..E.|NDIX K .-- -- - ' ----------------------------------------------- ' Caution Label Tht following or equivalent caution statements should be fixed on all containers of transformer askarals and the transformers themselves: ; This product contains Polychlorinated Biphenyls (PCBs). Care should be taken to prevent entry into the environment through spills, loakage, use. vaporization, or disposal of liquid or containers. Avoid prolonged breathing of vapors or mists. Avoid contact with eyes or prolonged contact with skin. If skin contact occurs, remove by washing with soap and water. Following eye contact, flush with water. In case of spillage onto clothing, the clothing should be removed as soon as practical, skin washed, and clothing laundered. ----------------------------------------- 1-------- ------ ------------ -- .. ....... .............. ------------------------ MONSANTO INDUSTRIAL CHEMICALS COMPANY SPECIALTY PROOUCTS GRqUP 00 N. LINDBERGH BLVD. I ST. LOUIS, MISSOURI 631S8 Vo > The information heroin regarding dbtaininq optimum results horn askarel fluids in your transformer has been accumulators by Monsanto tor over 40 years from thoexpurienceof makerkand usorsot askarel transformers and it ts believed will be helpful Nothing htnuin ahafl bn construed ks applying lo othur than askaret insulation. Dala and maintenance suijnnstlont tmrein do not apply to the other components ol the lienslormwr. A)l operating and maintenance suggestions recommended by the manufacturer of the transformer should also bit oatelullv fottomud. Because llwtc mointnnance directions amity only to the askarel insulation, Monsanto disclaims any liability for damage to property or injury to I parsons arising from transformer oppranon. J + MOMS 074770 r CUSTOMER SERVICE CENTERS AKRON. OjWO 44313 260 Springtida Drfva Montrote Development Park Tat. (216) 666-4111 ATLANTA. GEORGIA 30339 320 tntarhtata North Partway Suita 600 Tat. (404)432-7111 BOSTON. MASSACHUSETTS 02149 Everett Station Tat. (617) 387-S010 CHICAGO.; /LL/NO/S 3168 Dei Plaines Ava. Daa Ploincs, ttlmois 60018 Tat. (312) 296 6688 CINCINNATI. OHIO 45236 8041 Holbrook Road Tat. (613)984-1100 Detroit. Michigan 600 Northland Towata West Southfield, Michigan 48075 Tat. (313) 357-0910 HOUSTON. TEXAS 77027 1301 Pout Oak Towat SOSI Wimtha/mar Road Tat. (713) 621-9650 LOS ANGELES. CALIFORNIA 90022 6670 i. PtoUtta St. Tat. (213) 723-2492 Tat. (3021) 478-4600 V. 4o.63166 MCNS 074771 2-5MH-137V6 Lltlio In U S A.