NOMEX - DuPont

1 TECHNICALDATA SHEETNOMEX onlybyDuPontPERFORM WHEN THE HEAT S ONNOMEX TYPE 994 Type 994 is a densified, rigid board which hasa unique combination of superior resistance tocompression, even at elevated temperatures,along with relatively high oil absorptioncharacteristics. This combination results in aproduct which is especially useful as spacersor other structural components in liquid-filledsystems. With a specific gravity ranging to , Type 994 pressboard is available in 14thicknesses from to mm (40 to 380 mils),as is shown in Table propertiesThe typical electrical property values forType 994 pressboard in air and oil are shownin Tables II and III. The AC Rapid Rise dielectricstrength data of Table III represent voltagestress levels withstood for 10 to 20 secondtime periods at a frequency of 60 Hz. Thesevalues differ from long-term strength recommends that continuousstresses in dry-type transformers not kV/mm (40V/mil) to minimize the risk ofpartial discharges (corona).

2 The Full WaveImpulse dielectric strength data of Table IIIwere generated on flat sheets, such as in layerand barrier applications. The geometry ofthe system has an effect on the actual im-pulse strength values of the material. The di-electric strength data are typical valuesand not recommended for design values can be supplied upon data in Tables II and III are representativeof data for all thicknesses of Type 994. Type 994pressboard will pick up 8 to 10% oil byweight, with the oil absorption being inverselyrelated to density. This impregnability is rareamong rigid insulating materials. As withType 410 paper, the values for the propertieslisted will vary somewhat with changes inthickness and density. The effects of tem-perature on dielectric strength and dielectricconstant are shown for Type 410 paper inFigure 1 of the Type 410 data sheet. SinceType 994 pressboard is chemically identicalto Type 410 paper, its electrical propertieswill react similarly to temperature I TYPICAL PROPERTIESN ominal (mm) (mil)406080100120125160190 200240250275315380 Typical 1)(mm) (mil)39597998118125158188 197236250276316379 BasisWeight 2)(kg/m2) 3)(g/cc) ) ASTM D-374.

3 Method D, using 17 N/cm22) ASTM D-33943) Calculated using basis weight and thicknessTable II TYPICAL ELECTRICAL PROPERTIES IN AIRN ominal Thickness (mm) Constant 1) at 60 Factor 1) at 60 Hz (x10 3)710 Volume Resistivity 2) (ohm-m)10141014 Surface Resistivity 2) (ohm/square)10171017 Values shown above were measured at 23 C after drying at 120 C until bone dry 1) ASTM D-150 2) ASTM D-257 PLEASE NOTE:The properties in this data sheet are typical, or averagevalues and should not be used as specification otherwise noted, all properties were measured inair under standard conditions (in equilibrium at 23 C,50% relative humidity). Note that, like other products ofboardmaking technology, NOMEX brand pressboardshave somewhat different properties in the boardmakingmachine direction (MD) compared to the cross direction(XD). In some applications it may be necessary to orientthe board in the optimum direction to obtain its maximumpotential propertiesThe typical mechanical property values forType 994 pressboard are shown in Table data are representative of data for allthicknesses of Type 994.

4 As with Type 410paper, the values for the properties listed willvary somewhat with changes in thicknessand density. The effects of temperature ontensile strength and elongation are illustratedfor Type 410 paper in Figure 5 of the Type 410data sheet. The effects of exposure to hightemperatures will be similar for Type 994pressboard. As with Type 410 papers, thetensile strength of Type 994 pressboard atminus 196 C (77K) exceeds its room tem-perature value while elongation to break isstill greater than 3%. This makes Type 994 anexcellent candidate for cryogenic III TYPICAL ELECTRICAL PROPERTIES IN OILN ominal Thickness (mm) Strength - AC rapid rise1) (kV/mm)27 Dielectric Strength - Full wave impulse2) (kV/mm)70 Dielectric Constant3) at 60 Hz25 C C Factor3) (x10 3) at 60 Hz25 C 11125 C 16 Volume Resistivity4) (ohm-m)25 C 1015125 C 10131) ASTM D-149, 50 mm electrodes, rapid rise; corresponds with IEC 243-1, subclause , except for electrode set-up of 50 mm2) ASTM D-34263) ASTM D-1504) ASTM D-257 Table IV TYPICAL MECHANICAL PROPERTIESN ominal Thickness (mm) Strength1) (kN/cm2) Modulus2) (kN/cm2)MD360415XD255365 Flexure Strength2) (kN/cm2)MD99XD88 Izod Impact3) (joules/m)MD545355XD375285 Shear Strength4) (kN)4368 Hardness5) (shore D)8484 Elongation1) (%)MD1822XD1720 Shrinkage at 240 C6) (%) ) (%) Set6) (%) ) ASTM D-8282) ASTM D-7903) ASTM D-2564) ASTM D-7325) ASTM D-22406) ASTM D-339220019018017016015050 ASTM D-1674100 Temperature, CThermal Conductivity (mW/Meter K)

5 150200250454035302520100 ASTM D-2863100 Temperature, CLimiting Oxygen Index, %200300400 Thermal propertiesArrhenius plots of thermal aging behavior forNOMEX brand materials are exemplified byFigures 7, 8 and 9 of the Type 410 data aging of Type 994 pressboard atelevated temperatures has resulted in itsrecognition as a 220 C insulating thermal conductivity of mm (125 mil)Type 994 pressboard is shown in Figure 1 as afunction of temperature. DuPont has alsotested the thermal conductivity of this productimpregnated with various types of transformerfluids. This data is available upon stabilityThe compatibility of NOMEX brand paperand pressboard with virtually all classes ofelectrical varnishes and adhesives(polyimides, silicones, epoxies, polyesters,acrylics, phenolics, synthetic rubbers, etc.),as well as other components of electricalequipment, is demonstrated by the manyUL-recognized systems comprising NOMEX ,as well as longstanding commercial expe-rience.

6 NOMEX papers and pressboardsare also compatible with transformer fluids,including mineral and silicone oils, ester fluids,high temperature hydrocarbon fluids andother synthetic Limiting Oxygen Index (LOI) of mm (250mil) Type 994 pressboard at room temperatureis 39%, declining to 29% at 220 C. Materialswith LOI above (ambient air) will notsupport combustion. mm (250 mil) Type 994pressboard must be heated to above 380 Cbefore its LOI declines below the flammabilitythreshold, as is shown in Figure 1 THERMAL CONDUCTIVITY VS. TEMPERATURE mm (125 mil) Type 994 Figure 2 LIMITING OXYGEN INDEX (LOI) mm (250 mil) Type 994 NOMEX onlybyDuPont 2002 du Pont de Nemours and Company. All rights DuPont Oval logo, The miracles of science and NOMEX are trademarks or registered trademarks of du Pont de Nemours and CompanyH-52750 05/02 Printed in Fibers SystemsCustomer Inquiry Center5401 Jefferson Davis HighwayRichmond, VA 23234 Tel: (800) 453-8527(804) 383-4400 Fax: (800) 787-7086(804) 383-4132e-mail: Canada, Fibers SystemsP.

7 O. Box 2200 Streetsville Postal StationMississauga, Ontario, L5M 2H3 CanadaTel: (800) 387-2122 / (905) 821-5193 Fax: (905) 821-5177e-mail: Pont de Nemours International S. O. Box 50CH-1218 le Grand SaconnexGeneva, SwitzerlandTel: +41-22-717-5111 Fax: +41-22-717-6218e-mail: safety information is available upon requestThis information corresponds to our current knowledge on the subject. Itis offered solely to provide possible suggestions for your own experimen-tations. It is not intended, however, to substitute for any testing you mayneed to conduct to determine for yourself the suitability of our productsfor your particular purposes. This information may be subject to revisionas new knowledge and experience becomes available. Since we cannotanticipate all variations in actual end-use conditions, DuPont MAKESNO WARRANTIES AND ASSUMES NO LIABILITY IN CONNECTION WITHANY USE OF THIS INFORMATION. Nothing in this publication is to beconsidered as a license to operate under or a recommendation to infringeany patent AMERICADuPont do Brasil S.

8 Itapecuru, 506BR-06454-080 AlphavilleBarueri, Sao Paulo, BrasilTel: +0800-17-17-15+55 11 4166 8449 Fax: +55 11 7266 8904e-mail: Teijin Advanced Papers (Japan) LimitedARCO Tower,8-1, Shimomeguro I-chomeMeguro-ku, Tokyo 153-0064 JapanTel: +81-3-5434-6609 Fax: +81-3-5434-6605e-mail: PACIFICDuPont Teijin Advanced Papers (Asia) Limited1122 New World Office Building, East Wing24 Salisbury RoadTsimshatsui, KowloonHong KongTel: +852-2734-5363 Fax: +852-2734-5486e-mail: on the