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/ S har on P l a n t - ML-381 A p r i l 22, 1976 R e p l a c e m e n t s f o r PCB APR2 6 5 ft ML-071 Mr. R. L. Schwab ML-071 Mr. R. R. H a l v e r s o n c c : ML-381 - Mr D. R. G od fr e y ML-384 - Mr W. G. Chambers ML-385 - Mr S. D. Rambeck ML-385 - Mr C. L. Moore ML-384 - Mr K. R. L i n s l c y ML-384 - Mr D. A. Ya nnucci ML-384 - Mr W. O. Hughes ML-017 - Mr H. R. She pp ar d At t h e r e c e n t IEEE M e e t i n g i n New O r l e a n s , d u r i n g t h e T r a n s f o r m e r s Committee M e e t i n g , Ed Robb was g i v i n g h i s Subcommi tt ee r e p o r t when he was i n t e r r u p t e d by H. B. H a r g o l i a o f AEP on t h e q u e s t i o n , "Are t h e r e any r e p l a c e m e nt s f o r PCB?" Ed Robb a n s w e r e d a s f o l l o w s : " I t i s t o o e a r l y t o make any a n n o un c em en t s o f any r c p l a c e m e n t s f o r PCB f o r a t l e a s t t h r e e good r e a o n s . " These reasons are: 1. There has been no agreement, by any in su ran c e company u n d e r w r ite r s a s t o w h a t c o n s t i t u t e s a h i g h d e g r e e o f i n f l a m m a b i l i t y . On t h a t b a s i s no other liq u id has been evaluated. 2. There has been no g e n e r a l a c c e p t a n c e by t h e u s e r s o f any o t h e r fluids. 3. I f and when a now 1iquicl i s found, b e f o r e i t can be us ed i n any t r a n s f o r m e r s i t m u st meet c e r t a i n EPA r e q u i r e m e n t s . He s t a t e d t h a t t i l l s would t a k e some t i me even a f t e r a f l u i d was i d e n t i f i e d . T h e r e f o r e , he l o . l t t h a t t h e r e was no replacem ent in the immediate f u t u r e . The p u r p o s e o f t h e q u e s t i o n , o f c o u r s e , was - S h o u ld t h e IEEE F l u i d s S ub co mm it t ee become i n v o l v e d i n t h i s p a r t i c u l a r p ro bl em ? Ed R o b b ' s p o s i t i o n was t h a t he ca n s e c no way t h a t he c a n a p p r o a c h t h e p r o b l e m a t t h i s t i m e . / /' -f'f / / [i x <]/" S . 1 G. *Varg6', E n g i n e e r i n g Manager Medium FoVer T r a n s f o r m e r Department Sharon Transformer Division NPC00026419 753756 P* IEEE Std 76-1074 Revision of IEEE Std 76-1958 IEEE Guide for Acceptance and Maintenance of Transformer Askarel in Equipment Sponsor Transformers Committee of the IEEE Power Engineering Society O Copyright 1974 by The Institute of Electrical and Electronics Engineers, Inc. No part of thin publication may-br reproduced in any form, in an rlrctm nic rrtrirval system or otherwise, without the prior w hiten permission of the publisher. NPC00026420 753757 Approved May 24. 1973 IEEE Standards Board Hobrrt I). Briskman, Chairman Sava I. Sherr, Secretary Stephen J. Anerlln Suut Arimow < lim n K. IW rhlcr liirliard liicirlm i W iirrrn H. ('mik Lmii* f m ir r il Juv KoN fr loxtpli I.. Koepfimier W illiam It. Kruesi llfiiin m in J . I.mm I lon.ilil T M k Ii w I V i 5 A. Moorr -I. Ilavid M . I'help* nul W. Ko*rnthal (tustuve Sbupiru Ralph M. S liim fi* Hubert A. Smlrrman Frederick (I. T un ioel l^ e n ilrrt vnn H<m Hofiert V. U .chier K run o O Wm*rlirl Williuni T . W intriiiehiim ;v*V * M.T* f NPC00026421 753758 Foreword (T h u foreword is not a p a rt of ITTFT* S td 76*1974, IE E E Guide for Acceptance and M ahrtvnanee of T ransform er Askarel in Equipment.) Originally published in 195S as a trial-use guide for maintenance of transformer askarel, this stan dards document has been revised, updated, and approved as a full-status IEEE Guide. The new edi tion not only reflects current practice, it also takes into consideration recent environmental con cerns about materials containing polychlorinated biphenyls. The standard was developed and ap proved by the Insulating Fluids Subcommittee of the IEEE Transformers Committee. At the time it approved this document, its membership was: P.G. Benignus C L Blenklc J.E . Dind D.A. Gillies C. Keil A.H. Icke R .I. Low* W.H. Meade! E. L. Raab, Chairman E.L. Morrmori V.R. Mulhall J.C. Parker! P.S. Puah W.C. R einhardt R.L. Schwab T.K. Sloat t Deceased Following development and approval in the Insulating Fluids Subcommittee, this standard was reviewed and approved in the IEEE Transformers Committee. Membership in that committee was: J. H. Blake, Chairman G. W. Alexander, Vice Chairman C. C. Honey, Secretary L. C. Aicher R. Allustiarti R. J. Alton S. J. Antalis J. C. Arnold R. R. Bast P. L. B ell.tc hi S. Bennon H. E. Bonheimer J . V. Bonucchi 0 . R. Compton J. E. Dind J . D. Douglass J . C. D utton L. L. Dvorak H. P. Edler W. R. Farber S. L. Foster A. M. Fox E. R. Freitav C. R. French L. A. Gates R. F. Giiton A. Glassanos A. W. Goldman J. C. Gorub R. W. Green W. F. Griffard E. M. Gulachenski G. Gunnele G. H. Hall J . L. Harbelt W. L. H etherington K. R. Ilighton J. A. llollowrll E L. Hook G. W. IlifT W. D. Jordan G. K. K allenbach C. P. Kappeier R. B. K aufm an C. Keil F. J. Kelly L. A. Kenoyer T. S. Lauber C. Lindsay A. H. Locke A. M. Lockie L. W. Lone R. L. M acdonald HL B. Margolia D. E. Massey C. J. McMillen C. H. Mock W. H. M utschler P. Q. Nelson R. A. Nelson M. A. O m an S. Palmer A. F. Phillips X - L. Preston E L. Raab D. A. Roach . R. E. Russell L. J. S.vio R. L. Schmid R. L. Schwab L. R. S m ith * A. L. T an io n R. C. Thom as D. E. Truax R. A. Veitch F. J. Voxel J. P. Vora E. H. Wendt S. A. Wiencek G. C. Wilburn D. F. W inter J . R. Woodall W. E. W renn A. C. W urdack F. S. Young L R. Yule \ NPC00026422 753759  'J'STM. VSf Contents SECTION 1. Scop and Introduction facie 5 2. General Characteristics of Askarel .............. 3. Evaluation of Askarel Received in New Equipment 4. Classification of Service-Aped Askarel 5. Economic Factors................................ .......... 5 6 G 7 6. S a m p lin g ............................................................. 7. Askarel Tests and Their Significance 8. Testing Procedures . . 8.1 Field Screening . .. 8.2 Laboratory Screening 10 10 10 9. Reconditioning and Reclaiming Service-Aged Askarel 9.1 General .................... ... 9.2 Treatment After Exposure to an Arc ................. 9.3 Filtering Through Pry Blotter Paper to Remove Moisture and Extraneous Particles ................ 9.4 Fuller s Earth Treatment for Maximum Improvement of Power Factor and Volume Resistivity.... ............. 9.5 Addition of Scavengers ....... ............................... ...... 10. Handling Materials........................................................... 10 10 10 11 11 11 11 11. Askarel Used Under Mild Arcing Conditions 12. Askarel Under Excessive Temperature or Fault Conditions 12 12 13. Recommended Handling Precautions ............ 12 14. Storage. Handling, and Disposal........................................... 14.1 Drums ................................................. ................. 14.2 Tank Cars.............................................. ....... .... 14.3 Sampling .............................................. ......... 14.4 Effect of Light Exposure .......................... 14.5 Disposal................................................. ....... 13 13 13 13 13 13 15. Underwriters' Laboratories Reports .................................................... ......... 13 Appendix: Results of Survey of United States and Canadian Users of Transformer Askarel 15 Al. General ...................... ............... . ... A2. Testing . . . .................................................... ..................... .... A3. Reconditioning ............... ........................ ...... A4. Frequence of Testing .......................................................... 15 15 16 16 TABLES Table 1 Acceptable Characteristics of Askarel in New Equipment Table 2 Askarel Tests to Determine Classification ............ a S S a u l'i.ll'* " . I ' ' I ' " i n ' T Mill-- I'llllHlHI I I HI NPC00026423 753760 J!, \ lEEEStd 76-1974 IEEE GUIDE FOR ACCEPTANCE AND MAINTENANCE OF ! be kept in mind when interpreting electrical pling Electrical Insulating Liquids.1should be i I I test data. Because it is relatively polar and possesses high solvency power, askarcl is much more followed. New equipment with askarel exhibiting the characteristics given in Table 1 is considered ii electrically sensitive to trace contaminants acceptable. than insulating oil, and consequently the The significance of the foregoing and other ii choice of constructional materials destined for tests listed in this guide are discussed in Sec if use in askarel is very critical. This sensitivity tion 7. is reflected in the power factor and resistivity (specific resistance) of the askarel. It is important to note that, with the ex ception of water, the dielectric breakdown voltage of askarel is not generally adversely af 4. Classification of Service-Aged I fected by many of the contaminants tq which Askarcl its power factor and resistivity (specific resist ance) are so sensitive. In fact, the dielectric breakdown voltage of askarcl is somewhat greater than that of insulating oil. Therefore, the values assigned these dielectric fluids in newly supplied transformers are 30 kV min imum and 26 kV minimum, respectively. As with insulating oil, askarel must be kept dry. It can pick up moisture from exposure to humid atmosphere. Under similar conditions of exposure, askarel can pick up nearly twice t as much moisture when measured on a parts per million weight basis. A final obvious difference is that askarel is about one and one half times as heavy as wa ter, whereas mineral oil is lighter than water. This means that any free water present will It is extremely difficult, if not impossible, to indiente the value of specific tests and recom mended test limits for all possible existing ap plications of askarel. i t should also be recog nized that with the present state of knowledge no one test can be used as the sole criterion of condition of askarel. It is possible, however, to summarize the value and importance of cur rent tests and to suggest methods of treatment for the askarel being examined, such methods being based on current industry experience. Askarel may be placed in the following classi fications based upon composite evaluation of significant characteristics and on field and laboratory screening tests. I float on askarel, whereas free water in oil will Group /. This group contains askarel which be at the bottom. is in satisfactory condition far continued use. I.i Group //. This group contains askarel which requires only minor reconditioning for further service. (Reconditioning is the remov al of moisture and insoluble contaminants. Iit 3. Evaluation of Askarel Received in New Equipment T he usual method employed is filtration.) Group III. This group contains askarel in poor condition. It should be reclaimed or dis i carded depending upon economic consid ' Some users of askarel equipment find it de erations. (Reclamation involves the use of \i i l ft I4* sirable to make "as received tests" on all equipment. It is quite common to use the di electric breakdown voltage test and visual ap pearance as the most significant tests. If suit able equipment and trained personnel are methods and processes which result in a puri fication of the askarel. Treatment with an ab sorbing agent such as fuller's earth is most widely used.) Group /V. This group contains askarel in 4 * available, additional information may be ob such poor condition and requiring such drastained from the power factor, color, and mois il ture content tests. 4 In sampling askarel contained in ap 'ASTM Standard)! referred to in Ihr* auide are ob i; paratus, extreme care must be exercised in or tainable from Headquarters, American Society for Test * der to obtain a representative sample. ASTM ing and Materials, J916 Race Street. Philadelphia, Pa, end from the American National Standards Institute. Standard D 923-70 (ANSI C59.21-1973), Sam 1430 Broadway, New York. NY I001&. 6 NPC00026424 753761 IEEE Guide for Acceptance and M aintenance of Transformer Askarel in Equipment 1. Scope and Introduction The term askarel generally describes hwide ly used broad doss of nonflammable synthetic halogcnated hydrocarbon insulating liquids. In this guide, it applies solely to askarel in transformers, reactors, and accessory equip ment operated at power frequencies. Transformer askards contain PCB's (poly chlorinated biphenyls), which have been used in the UniLed States and elsewhere over the past 40years for many industrial and consum er applications. Recently, evidence has accu mulated to indicate that PCB's are widely dis persed throughout the environment and that they can have adverse ecological and tox icological effects. The Federal Interdepartmental Task Force report COM-72-10419, "Polychlorinated Bi phenyls and the Environment.*' dated May 1972, has recommended restricting PCB's to use in transformers and capacitors. Methods for handling and disposal of askarels and askarelimpregnated materials are given in Draft American National Standard, Guidelines for Handling and Disposal of Capacitor and Transformer-Grade Askarels Containing Polychlorinated Biphenyls, C107.1. This guide assists the power equipment op erator in evaluating askarel as received in transformers, reactors, and accessory equip ment operated at power frequencies and in his efforts to maintain askarel in serviceable con dition. It recommends standardized tests and evaluation procedures. Methods are outlined for reconditioning and reclaiming askarel whenever necessary. 2. General Characteristics of Askafel Askarels of various compositional types are used. Under arcing conditions the gases pro duced, while consisting of predominantly noncombustible hydrogen chloride, can yield varying amounts of combustible gases depend ing upon the askarel type. Insulation systems incorporating these ask arels and cellulosic or other organic materials may, when arced, produce gaseous mixtures which are moderately flammable. As a. pre caution, such gases 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. Askarel contained in apparatus as received from the manufacturer but prior to service op eration should exhibit certain properties in or der to insure satisfactory performance. It should be expected that askarel properly sam pled from such equipment usually exhibits characteristics somewhat different from those obtained on new askarel which has not been in contact with apparatus constructional ma terials. Experience has indicated th at vari- ' ation of some characteristics of the askarel will not impair the service life of the equip ment. However, certain essential properties must be retained if askarel is to perform reliably its dual role of electrical insulation and heat transfer agent. It must have adequate dryness and a dielectric strength sufficient to with stand the electric stresses imposed in service. It must retain a sufficiently low viscosity so th at its ability.to circulate and transfer heat is not impaired. It should not be allowed to be come so deteriorated or contaminated th at it adversely affects the operation of the ap paratus. In comparison to mineral insulating oil. askarel is a relatively polar material: that it. . its molecules are dipoles, free to rotate around their axes and responsive to orientation by electrical forces. Askarel also exhibits a much higher dielectric constant and capacitance - than insulating oil. and these differences must IEEE Std 76-1974 IEEE GUIDE FOR ACCEPTANCE AND MAINTENANCE OF sentative. This generally leads to erroneous must be heated in order to give off sufficient conclusions concerning quality and incurs vapor to form a flammable mixture with air loss of time, effort, and expense involved in se under the conditions of the test. Askarels have curing, transporting, and testing the sample. a flash point which is not indicative of a haz It is strongly recommended that all ofthe pro ardous condition unless followed by a fire cedures and precautions outlined in ASTM point. D 923-70 (ANSI C59.21-1973) or in the latest The fire point of a material that emits com revision thereof approved by the American bustible vapor may be defined as the temper National Standards Institute be followed. ature to which the material must be heated in Because of the high specific gravity (relative order to support continuous rombusion when density) of askarel (greater than 1), water and exposed to the atmosphere under prescribed *% some other impurities are most likely to be conditions. Askarels have no fire point. The found at or near the surface. The top sample, test is only of value, therefore, in showing therefore, is considered to represent the,worst ' whether the material has the nonflammable % condition. J characteristics required of on askarel. or has a large amount of combustible contaminant. il (4) Inorganic Chlorides. In the presence of water, chlorides con iuitize. Their corrosive 7 , Askarel Tests and Action can then be detrimental in th e life of Their Significance the apparatus in which the askarel is used. The presence of ionizable chlorides may be in There are a number of tests that can be ap dicative of arc decomposition of the askarel. plied to askarels as a basis for their classi (6) Neutralization Number. In the in fication as indicated in the foregoing. These spection of new askarels, the neutralization tests and Uieir significance are given in Table 2. value is of importance as a quality index of T ' (1) Color. The color of askarel is represent purity. ed by a numerical value based on comparison Since askarel is not subject to deterioration f with a series of numbered color standards by oxidation, small changes in the neu with transmitted light under prescribed con tralization value of service-aged askarels may i ditions. Color is chiefly significant as an in indicate the solution of basic or acidic materi \ dicator of contamination in askarel. Fre als from the various solid materials in contact quently this contamination is the result of sol with the askarel or the deterioration of such vent action between the askarel and other ma soluble materials to form basic or acidic mate terials in the apparatus involved. No definite rials. A large change in acidity may indicate relationship can be established between color and the physical and electrical characteristics decomposition of the askarel by an electric arc. of the liquid. (6) Pour Point. The pour point of askarel * <2) Dielectric Breakdown Voltage. The di may be defined as the temperature to which electric breakdown voltage of askarel may be the liquid ju9t flows under prescribed condi defined as the voltage at which electrical tions of test. The pour point has little signifi breakdown of the material occurs under pre cance as far as contamination or deterioration scribed conditions. The dielectric breakdown is concerned but may be used for type identi voltage of askarel is of importance as a mea-. fication. sure of its ability to withstand electrical stress (7) Power Factor. Power factor is the ratio without failure. It may also indicate the pres of the power dissipated in the askarel in watts ence of contaminating materials, such as wa to the product of the effective voltage and cur ter, conducting particles, dissolved con rent in volt-amperes, when tested with a sinu taminants. or the decomposition products re soidal field under prescribed conditions. Since sulting from an electric arc. A high dielectric askarel is not subject to oxidation, ap increase breakdown voltage, however, is not a certain of power factor value of the askarel in service indication of the absence of all contaminants. may be attributed to the presence of moisture, (3) Flash and Fire Point. The flash point of dissolved polar 'compounds, or other con askarel is the temperature to which askarel taminants. Depending upon the type of ap- 7 i8 \ i / NPC00026426 753763 TRANSFORMER ASKAREL IN EQUIPMENT Table 2 Askarel Tests to Determine Classification lEEEStd 76-1974 TeiU A5IM Standards (1) Color (2) Dielectric breakdown voIur (3) Flash and Tire point (4) Inordinic chlorides (5) Neutralization number (6) Pourpoint (7) Power factor (8) Refractive index (9) Uesifctivity (specific m blancv) (10) Scavenger content ( I t ) SpecUlcgravity (relative density) (12) Viscosity (13) Visual examination of service-aged askarels in the field (14 ) Volume of all in nil-contaminated askarel (IS ) Water content ___ D 2129-64 (1969HANSI C69.114-1970) D 877-67 (1971 MANSI C59.19-1968 (R1973)) D 92-7 2 D 1821-63 (1969MANSI C59.55-1963 (R1969)) D 074 64 (1968MANSI Z ll.1 3 1 -1964 (R1971)) D 664-58 (1968XANSI Zll.59-1958 (R1071 )) . D 97*66 (1971 MANSI Z11.6-1966 (R1972)) D 924-66 (1969XANS1 CS9.22-1067 (R1973)) D 160-70 D 1807-64 (1969)(ANSt C59.10S-1970) D 1169-64 ( 1969)(ANSI C59.51-195 (H I969)) D 1701-69 D 1810-63 (1970) (ANSI C59.68-196& (R1969)) D 88-66 (196BMANSI Z11.2-1966 (R1971)) D 446-72 (ANSI Zll.107-1973) D 1702-66 (1071 MANSI C59.104-1970) D 1808-63 (I960KANSI C69.07-1966 (R19G9)) D 1533-61 (1969MANSI C69.33-1963 (R1B69)) paratus and application, high power factor product, may be added to an askarel and .... due to contamination other than moisture sel- serves a useful function in improved preserva ***.***iWe.:`j>. dom impairs However, the the serviceability of the askarel. high power factor may influence tion of the 'submerged portion of the ap paratus should an arc occur. Measurement of ` the transformer winding power factor. scavenger content indicates the amount of (8) Refractive Index. Refractive index is de- protection available against dissolved arc- *fined as the ratio of the velocity of light in air formed gases and permits estimation or the to its velocity in the substance under pre amount of makeup additive required. scribed conditions. The refractive index of (11) Specific Gravity (Relative Density). askarel varies with its composition and with The specific gravity (relative density) of an the nature and amount of contaminants held askarel is the ratio of the weights of equal vol in solution. Changes of refractive index of ask- umes of askarel and water at 15.56" C. Specif . arel in service may be useful in estimating ic gravity (relative density) may be useful for compositional change and degree of soluble type identification or to determine marked contamination. compositional changes. (B) Resistivity (Specific Resistance). Vol (12) Viscosity. The viscosity of an askarel is ume resistivity (specific resistance), in ohm- its resistance to uniformly continuous flow, centimeters, of askarel is the ratio of the dc without turbulence, inertia,' or other forces, potential gradient in volts per centimeter par and is usually determined by measuring the alleling the current flow within the sample to time^nf flownf a given quantity of liquid under the current density in amperes per square cen controlled conditions. Viscosity of askarels timeter at a given instant of time and under varies with temperature, and for that reason prescribed conditions. The resistivity of ask is always designated at a specified temper arel is a measure or its electrical insulating ature. properties. High resistivity normally reflects Viscosity is a controlling factor in the dis low content of free ions and ion-forining parti sipation of heat by convection in insulating cles and indicates u tow concentration of con and cooling liquids. This is particularly im ductive contaminants. portant in transformers and other apparatus (10) Scavenger Content. Askarels are de where heat generated in windings and cores composed by on electric arc with the evolution 'must be largely removed by transmission of hydrogen chloride gos. A scavenger, which through the liquid to a heat exchanger or the reacts chemically with dissolved hydrogen containing case. It is also a factor in the rate chloride gas .to form a nonvolatile reaction _of impregnation of certain apparatus. 9 "S& HPC00026427 753764 lEEEStd * 76-1974 IEEE GUIDE FOR ACCEPTANCE AND MAINTENANCE OF (13) Visual Examination of Service-Aged some time and have proved satisfactory. In Aikarcls in the Field. This method provides addition to the preceding tests, some oper for field examination of Bei-vice-aged oskarels, ators with suitable field equipment and campled from equipment in service, chiefly for trained personnel may wish to gain additional the purpose of determining whether labora information by use of a power factor test. In tory tests are required. This method may be of interpreting results of these tests, consid significance in visually detecting cloudiness eration must be given to other characteristics which is an indication of the presence ofmois of the askarel. ture. carbon particles, which may show an arcing condition, or color which is chiefly sig nificant as an indicator of contamination in askarcls. No definite relationship has been es tablished between color and the physical and electrical characteristics of the liquid. Hy the use of this method it may he possible to extend the period between routine laboratory tests. (14) Volume of Oil in Oil-Contaminated Atkarel. The quantitative determination of the volume of oil in oil-contaminated asknrel is important as a check on the degree of con tamination and as a means of ascertaining when the nonflammable property of this fluid * has been impaired to such an extent that it can -no longer be classified as a nonflammable liquid. . (15) Water Content. The water content is 8.2 Laboratory Screening. Askarel requiring laboratory evaluation will vary widely in con dition, depending upon the degree of con tamination. There are many tests of a re search nature which could be applied, but the general use ofsuch tests would be impractical. The following tests, therefore, are believed to be adequate for classifying service-aged ask arel: (1) Dielectric breakdown voltage (2) Inorganic chlorides (3) Neutralization number (4) Power factor or resistivity (specific re sistance) (5) Specific gravity (relative density) (6) Visual condition and color (7) Water content that amount of water, expressed in parts per million by weight, which is present in the liq i uid, The test is significant in that It will show 9 . R e co n d itio n in g an d R eclaim ing the presence of water which may not be evi Service-Aged Askarel dent from electrical tests. Changes in water iI content of askarel in service may be indicative 8.1 General. Askarel does not oxidize, sludge, .of undesirable operating conditions requiring or decompose in normal transformer use. It I correction. will break down when subjected to an elec I trical arc. If the arc exposure has been of long duration, it is usually best to discard the fluid. 8, Testing Procedures However, when arc exposure has been rela tively mild or if the askarel is merely con i The testing of oskarels is best accomplished tam inated with moisture and other con !! in adequately equipped laboratories. How ducting impurities, restoration is practical. ever, some find it advantageous to make field An exception is the lack of a practical method screening tests. for removing mineral oil from askarel. Askarel 8.1 Field Screening. Field screening tests are usually made to determine which samples of askarel may require laboratory investigation. contaminated with over 2 percent by volume of transformer mineral oil may no longer be classified as a nonflammable liquid. I Since most tests of askarel con be done best 9.2 Treatment After Exposure to an Arc. with laboratory equipment and trained per When askarel b exposed to arcing, hydrogen sonnel, field tests are usually limited to visual chloride gas is liberated. Some hydrogen chlo ii inspection and dielectric breakdown voltage. ride will remain dissolved in the askarel and No standardized procedure is available at ' must he removed as quickly as possible.. i I the present time for performing field tests on This done by bubbling about 220 ft1(6.23 service-aged askarel or for classification. Port m3) (1 cylinder) of dry nitrogen through each able dielectric test sets have been available for _ 100 gal (3.785 m3) of askarel. The nitrogen 10 NPC00026428 753765 ** TRANSFORMER. ASKAREL IN EQUIPMENT IEEE Std 76-1974 should be admitted at the bottom of the tank or container vented sufficiently to allow the nitrogen to escape, while preventing entrance of moisture. This procedure for removing hydrogen chloride is recommended even though the askarel contains a hydrogen chlo ride scavenger. 9.3 Filtering Through Dry Blotter Paper to Remove Moisture and Extraneous Particles. Since undissolved moisture will be at the sur face of the askarel. any simple means should be used to drain or siphon off excess water. The final drying is done by circulating the askarel through do' blotter paper. The askarel temperature should not exceed 60*C. Several passes through multiple layers of freshly dried paper may be required. Filtering should not be done when the relative humidity exceeds 75 percent. The filter paper must be dried immediately before use. For best results, the paper is spread for maximum surface exposure in a hot air cir' V culating oven and heated for 4 to 6 h at no*c. After filtration the dielectric breakdown voltage ofthe askarel should be at least 35 kV. 9.4 Fuller's Earth Treatment Tor Maximum Improvement of Power Factor and Volume Re' * atetfvity. The askarel should be relatively dry prior to final refinement with conditioned fuller's earth. Most operators prefer a portable fuller's earth refining apparatus such as a plate press or an earthen cartridge type filter. As this ap paratus involves recirculation, the askarel should be removed from the top uf the tank and returned at the bottom, because free mois ture and most of the other undissolved con taminants will be found near the surface of the askarel. Since these recirculating proce dures can introduce air into the askarel. suf ficient time (at least 4 h and preferably over night) should be allowed Tor the air to escape before re-energizing the apparatus. When a filter press is used, the plates are fit ted with dry filter paper. This is coated with 0.1 to 0.2 percent by weight of dried fuller's earth based on the weight of askarel to be treated. (Askarel weighs nearly 13 pounds per U.S. gallon, 1556 kg/m'.l The finely divided clay should be activated and dried to not over 1 percent of moisture by heating for 12 h in shallow trays at about 200* C, immediately prior to use. To deposit the fuller's earth evenly, about one-third of the total quantity is stirred into a small portion of the askarel in a clean con tainer. This mixture is pumped through the filter, then followed with two more one-third portions. Then the askarel is pumped from the top level of the tank, through the filter, and returned to the tank at the bottom. It is desirable that the askarel temperature not ex ceed 60* C during the filtering operation. Circulation is continued until the fluid is clear and tests show that the electrical proper ties are fully restored. 9.5 Addition of Scavengers. Only slight loss (by selective absorption) of the hydrogen chlo ride scavenge ocxoiit. when askarel is refined by treatment with 0.2 percent by weight of fuller's earth at a temperature not above 60* C. Significant removal of the additives can result from treatment with much larger amounts of fuller's earth. Initially 0.1 to 0.2 percent fay weight of scavenger, usually an epoxide, is incorporated in modern transformer askarel. Inquiries about replenishing the additive should be di rected to the transformer manufacturer, or to the supplier of the fluid. 10. Handling M aterials All common metals are satisfactory for use with askarel in dry environments. To avoid rust, it is preferable to use.stainless steel or aluminum for filter presses or equipment used intermittently or in the presence of moisture. Because stainless-steel piping may be diffi cult to fabricate, -the use of aluminum or gal- X9xuzcd-stee[ is'more common. * Pipe connections should be welded wherev er possible. Flanged connections are very good when fitted with a sufficient number of bolts to hold the gasket seal securely. Where readily removable connections are heeded, deep pipe threads should be cut and wrapped with tetrofluoroethylene tape* to make the seal. 'Such as Teflon. 11 W & B fG SH Sl' V: ' AWwVKKHft-- V-HPC00026429 753766 IEEE Sid 76 1974 1F.EE GUIDE FOR ACCEPTANCE AND MAINTENANCE OF In addition to tetrafluorocthylene. other materials completely compatible with askarel and suitable for gaskets are certain elasto mers 'and stainless-steel rings with an accept able elastomer4between the steel laminations. Silicone elastomer does not have good abra sive resistance and it is not suitable for use with mineral oil. Fluoroelastomers have rela tively good abrasion resistance and are resist ant to both askarel and mineral oil. If a fine-grain cork-nitrile rubber-com position gasket is used, it is desirable to coat the exterior of the seal with room-temperature curing epoxy cement or RTV silicone cement. Well-cured or dried adhesive cements oYde waxed orange shellac, dextrine glue, polyvinyl alcohol acetate." phenolic or epoxy, are rela tively noncontaminating to askarel. . Suitable hoses are those of the flexible metal type, or those in which only tetrafluorocthylene- or silicone polymers arc in contact with the askarel. . The preferred valves are those in which only >"i-fK.,:*stainless steel is in contact with the askarel. ' `Wher e required, the stainless-steel valve may be seated with tetrafluoroethylene.-* Also brass valves are acceptable. Asbestos graphite packing7is suitable valve stem packing. Centrifugal pumps suitable for handling hot oil are the recommended type. Gear type pumps are not desirable. All wetted surfaces of the pump should be of stainless steel. The shaft seal should be the external mechanical (carbon ring) type to eliminate packing mate rial and its exposure to askarel. All askarel handling equipment should be reserved solely for use with askarel. and should not be used interchangeably with mineral oil. 11. Askarel Used Under Mild Arcing Conditions duction regulators, where operating switches are continually producing slight arcs, in transformer de-energizing switches, etc. Un der normal operating conditions, deteriora tion of the askarel is very slight. However, im properly adjusted or defective switch in this type of apparatus can produce excessive and prolonged arcing and accelerated deteriora tion of the askarel. it is recommended that when askArel is used under these conditions, checks of the liquid, especially for moisture and dielectric strength. Ie made more fre quently than when it is used only as a cooling and insulating fluid. Deterioration of this type is indicated by a blackening of the liquid. It can usually he reconditioned as previously described. Special attention should lie given to maintaining the scavenger at the appropriate concentration. 12. Askarel Under Excessive Tem per ature or Fault Conditions Chlorubenzenes used in transformer askarels begin to boil at temperatures of about 205*C under atmospheric conditions. If the material is heated to such high temperature in a sealed system, pressure develops. Pressure will also develop in the system if the askarel is arced sufficiently to generate copious hydro gen chloride eas. Therefore, it is recommended that wherever possible, sealed askarel-filled equipment be provided with pressure relief devices. These devices must be larec enough to provide imme diate relief at a definite pressure, and to pre vent further buildup of pressure if decomposi tion continues. It must be remembered that the presence of devices of this sort does not necessarily preclude the rupturing of con taining vessels, since pressure buildup can be extremely rapid under violent arcing condi tions. ' * Askarel is used, to some extent, in ap paratus where it is subjected to light, inter mittent arcing, such as in self-contained in- 13. Recommended Handling Precautions ISuch M Viun and Silaatic. *Such aa Viton. Teflon, or ailkonc. Such at Viton. Such as Elvano). 'Such aa number 117 braided Oarlock type, or Raybeato* M an h attan type 36S-C. It is generally accepted that the exposure to askarel is not hazardous, provided dimple pre cautions are taken. Most people can handle askarel in the sarnie manner as insulating oil without fear of adverse effects. Some people 12 / JfiSl N PC00026430 753767 TRANSFORMER ASKAREL IN EQUIPMENT / are allergic to askarel. and continued exposure (___^m ay result in skin irritation. Therefore, direct "^contact with askurel and its vapors, particu- / larly when hot, should be avoided. This, com- / bined with personal cleanliness, should con- / stitute an adequate safeguard against harmful I efiects. Eye protection (glasses, shields, etc) / are required. The use of any type glove should / - be avoided. Medicinal washes or detergents / followed by an application of cold cream or sii* V icone-beariiig hand lotions" have been suc- cessfully used to eliminate irritation resulting Jj from askurel coming into contact with an ' open cut or skin abrasion. A drop of castor oil / has been found to neutralize, in most cases, ir- [ ritation caused by contact of uskarel with the V eyes. . \ . Exposure to concentrated askarel vapors ' j should be avoided, particularly in closed un- . I ventilated rooms. As with many volatile liq- / uids, the vaporization of askarel increases rap- . I . Idly with temperature. Therefore, ventilation jwW/ -.`v which is adequate for handling askarel at room temperature may not be adequate for \ handling askarel at elevated temperatures. \ The gases produced when askarel is de- 1 composed by very high temperatures or an j electric arc in the presence of air or organic in* / nilatine materials contain a high percentage . / of hydrogen chloride and small percentages of l carbon dioxide, carbon monoxide, and oxygen. \ Very small concentrations of this com* / bination of gases are very unpleasant and irri* I tating. thus giving ample warning of their Lj presence. masks ate The atl-puTpose canister-type gas suitable for protection from cases liberated from decomposed askarel. IEEE Std 76*1974 Askarel must be kept dry. It can pick up moisture from contact with humid air. Drums of askarel should not be stored outdoors in an upright position, as water can collect in the dish of the drum head and can be drawn into the drum under certain conditions. Drums should be stored on their sides with the bungs downward and under cover. It is preferable to store drums indoors. Askarel should not be transferred into drums that have previously contained other materials. 34.2 Tank Cara. Tank cars are solid alumi num, or steel lined with aluminum, or a zinc- tin coating. It is desirable to provide canopies for un loading askarel cars. The car should not he opened in the rain or snow. It is desirable to not open the car if the relative humidity ex ceeds 75 percent. Precautions must always be taken to exclude dirt. 14.3 Sampling. See Section 6 for a discussion of sampling. 14.4 Effect of Light Exposure. Prolonged ex posure to ultraviolet light (sunlight, some flu orescent lights) should be avoided. Askarel can decompose under such conditions. Sample bottles are preferably of the amber gloss type. 14.5 Disposal* Methods for disposal are given in Draft American National Standard, Guide lines for Handling and Disposal of Capacitor and Transformer-Grade Askarels Containing Polychlorinated Biphenyls. C107.1. 14. Storage, Handling, and Disposal 15. Underwriters* Laboratories Reports Transformer askarel can be handled in The Underwriters* Laboratories have ex about the same manner as transformer miner haustively examined, at the electrical manu al oil. facturers* requests, the miscellaneous hazards 14.1 Drums. The askarel drum is made of steel lined with a specially selected material properly cured. Galvanized drums may also be used. involved in the use of askarel and askarel- filled apparatus. Reports have been issoed to the respective manufacturers covering1the trade-named askarels being considered. It is suggested that interested users of transformer \- askarel contact the manufacturers for this in 'Such u SllkUre. - formation. 13 hpcooo2643i ' 753768 Appendix Results of Survey of United States and Canadian Users of Transformer Askarel (T his ppendis n not a port of IE E E Std 76-1974. IE E E Guide for Accoptince and M aintenance of T T arn fam x r Askarel in Equipment.) y e Al. General This survey of the United States and Can adian users of askarels was made in 1966 in or der to show the practices followed in testing, reconditioning and reclaiming of askarels. Of the 96 inquiries sent out. 50 replies were re ceived with usable information, which is a 52 percent return. All of the following data are shown as a percentage of those returning the questionnaires and it should be pointed out S&V* *^at R*'* `ncludes information from both TM / -- manufacturers as well as users and no attempt has been made to classify them according to the size of the systems involved. Of the users of askarels who returned the questionnaire, 32 percent make only field tests: 32 percent make only laboratory tests: 24 percent make both field and laboratory tests: and 12 percent make no tests at all on askarels. Most all muke tests at a fixed time interval and the largest group follow' a yearly schedule. Of those users returning the ques tionnaire. 67 percent recondition askarel. which is below acceptable limits, and the most popular method employs the combination fuller's earth and blotter press. This survey was made purposely to deter mine the types of tests being made by askarel users and to give an indication of acceptable limits. The following data are the overall re sults of the questionnaire. A l.l Field Tests for Askarel. Of askarel users. 56 percent do some type of field testing. Of these. 93 percent make a test for dielectric breakdown voltage. At least two field tests ure made by 57 per cent as follows: (1) Dielectric breakdown voltuge (2) Visual examination and color Other tests user! in decreasing order of fre quency are power factor, neutralization num ber. and moisture. A1.2 Laboratory Testing for Askarel. Of ask arel users. 56 percent make an average of four tests in their laboratories on samples. Of these. 93 percent determine the dielectric breakdown voltage. At least four tests are made by 64 percent as follows: (1) Dielectric breakdown voltage (21 Color and condition (3) Neutralization numbeT (4) Moisture content (5) Power factor Other tests used in decreasing order of fre quency are inorganic chlorides, resistivity (specific resistance), and specific gravity (rela tive density). A1.3 Askarel in New Equipment. Of the users. 80 percent test the dielectric breakdown volt age of askarel in new equipment. Also tested by 22 percent are the following: (1) Power factor , 12) Moisture Other tests used in decreasing order of fre quency are neutralization number, inorganic chlorides, and resistivity (specific resistance). A2. Testing Most reporting companies test used askarels and approximately (1) 32 percent use only field tests (2) 32 percent use only laboratory' tests (3) 24 percent use both field and laboratory tests (4) 12 percent do not test The relative importance of the field tests are as follows: (1) 93 percent dielectric breakdow n voltage (2) 40 percent color and visual examination (3) 14 percent power factor (4) 11 percent neutralization number 15 NPC00026432 753769 is s m The average limits on service-aged samples ere as follows: (1) Dielectric breakdown voltage: average 27 kV, range 20 to 35 kV (2) Power factor: average 10 percent, range 2 to 40 percent (3) Neutralization number: average 0.12. range 0.05 to 0.5. (4) Inorganic chlorides; average 0.5. range 0.01 to 2.0 (5) Moisture: average 45 parts per million, range 40 to 55 parts per million The average limits on uskarel in new equip ment arc as follows: * (1) Dielectric breakdown voltage: average 30 kV, range 22.5 tu35 kV (2) Power factor: average 3 percent, range 0.05 to 5 percent. (3) Moisture: average 32.5 parts per million. Tange 20 to 50 parts per million A3. Reconditioning 5S. * .. Of the users of askarel returning the ques tionnaire. G7 percent recondition askarel from transformers: 111 73.5 percent prefer the combination full er's earth-blotter press (2) 17.5 percent use only the blotter press (3) 9 percent use only fuller's earth The average limits on reconditioned askarels, are as follows: (1) Dielectric breakdown voltage: average 29 kV, range 23 to 35 kV (2) Power factor: average 3.5 percent, range 2 to 15 percent (3) Neutralization number: average 0.10. range 0.01 to 0.5 (4) Moisture: average 35 parts per million, range 30 to 60 parts per million A 4. Pxcqucnpy of Testing The frequency or testing practiced by askarc! users is as follows: (1) 53 percent test every year (2) 17.5 percent test every 5 years (3) 17.5 percent test when there is a reason for testing (4) 9 percent test every 2 years (5) 3 percent test every 6 months Most users test all askarel units at the same interval regardless of rating. 16 NPC00026433 753770 ASTM AND IEEE TECHNICAL COMMITTEE ACTIVITIES A. E. Baker Doble Engineering Company * The purpose of this brief report is to inform you of the various insulating fluid activities now being undertaken by certain technical societies notably IEEE and ASTM. The following arc highlights of the various Committee actions. IEEE (INSULATING FLUIDS SUBCOMMITTEE) Project P637, "Guide Tor Reclamation of Insulating Oil and the Criteria for its Use," has essentially been completed (sent to Transformer Committee for approval) with the inclusion of some changes in definition, of terms (reconditioning, rcrefining), nnd general editing. Last minute items emphasized thermal limitations of oil/clay processing and the ensuing deleterious effect on the inherent oxidution stability as well as the inhibitors present. Although not receiving unanimous support, a section on the "energized" treatment of oil is included with appropriate cautionary statements. Project P76. "Guide for Acceptance and Maintenance of Transformer Askarel Equipment," is to be reaffirmed and reissued with the inclusion or a preamble which in part states, (1) The document is considered to be of value to the industry until such time as 'all askarel-filled transformers have been removed from service and, (2) Federal Regulation 40CFR Part 761 must be consulted and adhered to in all cases. Project P799 "Guide for Handling and Disposal of Askarels." The previous work or ANSI C107 is the starting point for this guide being organized by a recently established working group. Committee discussions covered items such os the need for EPA-approved standard test for PCB oil analysis, definition of terms e.g., "nondetcctable" and the ambiguity of certain legal regulations. The guide should cover, among other things, labelling, transport, storage, disposal (oils as well ns solids-- Fullers earth), definition of leaks, weeping, etc. The EPA is preparing a guide on spills which could be helpful First drafts will be discussed at the October meeting. IEEE ELECTRICAL INSULATION SOCIETYLIQUID DIELECTRICS COMMITTEE This Committee and its several working groups are involved in the preparation of four guides all of which are in various stages or preparation. These guides will cover the following: Subcommittee I PAR772--Recommended practice for testing the electrical performance or composite insulation containing liquid dielectrics. Main areas of testing include: physical and chemical voluigc endurance, thermal endurance, and combined effects. Subcommittee II PAR 774--Assessment of the fire hnznrds of insulating liquids used in transformers. The evaluation is based on the Factory Mutual heat release rate test. 47AIC80 INSULATING FLUIDS See. 10-ftil NPC00026434 753771 Subcommittee III FAR 773--Health and environmental assessment of new dielectric fluids. A draft has been prepared and is being edited. Subcommittee IV PAR 797--Recommended practice for transformer retroPilling. Items to be included have been assigned. The Committee also agreed to possible participation in EPA or other agency rulemaking if future regulations impact user interests. A5TM The Subcommittee on chemical tests reaffirmed several test standards covering inorganic chlorides and sulfates (D 878); corrosive sulfur (D 1275): sludge formation by the oxidation bomb (D 1313); spot test for acidity and polar contaminants in used oil (D 1902); thermal stability of oskareb (D 1936); and by hydrolyzable chlorine content of askare^s (D 1820). Three possible methods for field detection of PCBs in oil are under consideration and include a portable gas chromatograph, a silver nitrate precipitate lest, and a photoionization technique. The three methods are still being evaluated. The section on low temperature properties has been considering additional tests to characterize the response of paraffinic base oils. The Cannon rotary viscometer which provides two values "start up" and "running" was proposed. Much of the activity of the Subcommittee on physical tests recently has been devoted to PCB test methods. A number of procedures have been reviewed and plans are underway to conduct a round robin evaluation of the most promising method. Test oils will include new and used oils each "spiked" with 5. SO and500pptnorukBrelsfi.e., AroclorsTM 1242,1254, and 1260. To complement the test method D 3612, Analysis of Oases Dissolved in Electrical Insulating Oil, the Subcommittee is proposing a method for determining the solubility of typical gases in oil. There is an apparent need for redetermination of the solubility coefficients now referenced in the test method. The section on transformer oils is. recommending that gassing tendency limits be added to the . specification D 3487, Mineral Insulating Oil Used in Electrical Apparatus, as an interim control on aromaticity. The aniline point, of questionable value in this regard, ceases to have significance as oils become more paraffinic. The Committee was requested to consider more definitive test methods e.g., specific optical dispersion, carbon type composition, as a means or specifying aromatic content. The limit proposed Tor gas evolution is 4-20 (Procedure A) and +30 (Procedure B) microliters per minute. The Subcommittee on electrical tests reviewed results of recent power factor (dissipation factor) imerlaboratory tests. The results showed reasonably good values for low power factor oils (0.3%). However, the values obtained for oils with power factors near 1.0% were less consistent See. 10-502 s * INSULATING FLUIDS 47AIC80 NPC00026435 753772