ML20132C393

Thermalistic 83 Fire Retardant Coating for Grouped Electrical Conductors

ML20132C393
Person / Time
Site:	Vermont Yankee
Issue date:	08/22/1983
From:	Knight D, Danni Smith FACTORY MUTUAL RESEARCH CORP.
To:
Shared Package
ML20132C391	List: ML20132C386 ML20132C393
References
NUDOCS 8507300237
Download: ML20132C393 (6)

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THERMALASTIC 83 FIRE RETARDANT COATING FOR GROUPED ELECTRICAL CONDUCTORS J

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FIRE-STOP SYSTEMS 3727 EL JAMES DRIVE

] SPRING, TEXAS 77373 J

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, f '_ '_ L_ l i I AUGUST 22, 1983

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Factory Mutual Research 1,.

8507300237 050726 PDR ADOCK 05000271 F PDR

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Factory Mutual Research 1151 Boston-Providence Turnpike j P.O. Box 688 f ,. Norwood, Massachusetts 02062 OJ0A4.AF August 22, 1983 e (3971)

TifERMALASTIC 83

, FIRE RETARDANT COATING FOR GROUPED ELECTRICAL CONDUCTORS from

. FIRE-STOP SYSTEMS, 3727 EL JAMES DRIVE SPRING, TEXAS 77373 1.1 Fire-Stop Systems requested approval of their Thermalastic 83 Fire Retardant Cable Coating for use as a protective coating for electric power and control cables when applied at a minimum dry coating thickness of 1/16 in.

(1.6 mm).

1.2 Thermalastic 83 is a water based, high solids elastomer with a service temperature range from -300F (-340C) to 1950F (910C) after f curing.

1.3 As the product contains water, precautions should be taken to ensure

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that any storage, transportation or application of the material is done at temperatures above freezing and in accord with the manufacturer's instructions.

] 1.4 This coating is intended to prevent flame spread in conductors when lJ exposed to a moderate fire source that might occur from arcs or sparks falling or occurring in the cable tray, or from fire exposure of combustible trash or foreign material around the cable (s) in grouped or trayed condition. The coating is not intended to maintain cable protection under severe and extended fire exposure conditions.

1.5 When applied according to the manufacturer's instructions, the 7

protective coating does not of itself require electrical de-rating.

II DESCRIPTION (See Attached Product Data Sheet) 1

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2.1 Surfaces to be coated with Thennalastic 83 must be clean and free f rom oil, grease and dirt. Clean-up is accomplished with clean water before the material cures.

.1 2.2 Application of Thermalastic 83 is by brush, spray, trowel or glove.

The coating dries to the touch in four hours and cures thoroughly in 3 to 5

.1 days. Thermalastic 83 applied at 1/8 in. (3.2 mm) wet to obtain the minimum 1/16 in. (1.6 mm) dry film thickness when cured.

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FoCIORY MUTUAL O(5(AOCH COOPOS A llON Page 2 OJ0A4.AF 2.3 Af ter curing, the coating remains sufficiently pliable so that u individual cables may be removed from a grouping if necessary and damaged portions of the protective coating may be repaired by spraying. The coating, as applied, has good adhesive properties and will stick readily to vertical and overhead surfaces. When cured and exposed to flame, it does not melt or drip, but merely carbonizes.

III FARKINGS Thermalastic 83 is available in 5 gal. (18.9 liter) co' tainers. The manufacturer's name and address, product name, production batch number, '

application and storage instructions, and the Factory Mutual mark of approval ,

are shown on the container label.

IV TESTS 4.1 Four strips of Thermalastic 83, each 18 in. (457 mm) long, 3 in. .

(76 mm) wide and 1/16 in. '(1.6 mm) thick (dry) were prepared and conditioned at room temperature. Two specimens were clamped vertically and parallel '  !

1/2 in. (13 mm) apart to expose 17 in. (432 mm) below the clamp. Cage marks l

were made 3 in. (76 mm) and 17 in. (432 mm) from the free (lower) end. A "

Bunsen burner with a 2 in. (51 mm) total flame height with a 1 in. (25 mm) ,

inner core was then positioned vertically under the free end of one specimen for a 2 min. period with the flame cone just touching the specimen. q Examination at the end of the fire exposure period showed flames did impinge 't and scorch the specimens up to 2 in. (51 mm) above the lower gage mark. There 1 was some disintegration of the specimen at the lower edge of the specimen when j handled by squeezing lightly between the thumb and forefinger. The area above the 3 in. (76 mm) gage mark remained intact. Direct flame impingement did .

cause some loss 'of flexibility above the 3 in. (76 mm) gage mark, but this '

area was considered structurally sound. -

a 4.2 The test outlined in Paragraph 4.1 was repeated with the second set i

of specimens and the results were similar. These test results satisfy -

approval requirements which allow no degradation of the specimen above the 3 in. (76 mm) gage mark and no scorching or burning above the 17 in. (432 mm) '

gage mark.

4.3 Ten 3 ft. (0.9 m) long samples of 2/0, 600 V, 900C rated insulated s cooper cables were given a high potential check of 1,000 V, plus 200% of rated voltage for 1 min. The cables were wrapped tightly in aluminum foil and the 1

potential applied between the foil and the copper conductor and any leakage J current in milliamps (mA) was recorded for each cable sample. Cables were then coated according to the manufacturer's instructions and 'af ter the -

recommended curing time, this high potential test was repeated to insure that no change or damage had occurred to the cable insulation pri'or to or during d the coating application. (This test is also repeated after the fire test described below as an added means of determining any insulation breakdown). "1

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l .9 FACTORY MuiUAL RE SE ARCH CORPOR A TION

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'j, 4.4 Three of the above 3 ft. (0.9 m) long coated cables were individually

heated electrically with 150% of rated current (430 A) until the conductor

'i- (wire) temperature stabilized at 1970F (920C). A flame from a Meeker gas burner, adjusted to give an overall naturs1 gas flame height of 5 in. (127 mm) with a 3 in. (76 mm) inner cone, was applied to the horizontally positioned cable for 2 min. with the tip of the inner cone touching the bottom of the coated cable. At the end of a 2 min, flame exposure, there was simultaneous burner flame cutoff and electrical shutdown. All flaming extinguished d '

immediately. Af ter cooling, the charred and scorched area of the first sample exposed to the burner flame was measured and found to be less than 4 in.

, (102 mm) in leng'th. This satisfies approval requirements that burning shall not continue longer than 1 min. af ter flame cutoff and the burned (exposed) 1 area shall,not exceed 9 in. (228 mm) in length.

J 4.5 Results of the second and third cables exposed to the test described

{ .. in Paragraph 4.4 were similar. The three cables were then given a repeat of the high potential test described in Paragraph 4.3 and current leakage averaged 0.65 mA. This satisfies the approval requirement that leakage

%q k~J current shall not exceed 5.0 mA when measured between a conductor and the outer jacket during this high potential test.

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4.6 A 3 ft. (0.9 m) length of cable coated with Thermalastic 83 was

'- subjected to a salt water test consisting of 8 hr. submerged, alternating with 16 hr. of drying in a 24 hr. span over a 30 day period using a 1% salt

• ] solution with a water temperature of 1500F (660C). At the end of this

. .] period, the sample was allowed to dry for 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. There was no disintegration or deterioration of the coating from this exposure. The cable sample was then subjected to the fire test described in Paragraph 4.4 and a

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high potential test (see Paragraph 4.3); the results of these tests were satisfactory.

4.7 Two 3 ft. (0.9 m) lengths of cable covered with Thermalastic 83 were

.{- subjected to alternating temperatures of 1600F (710C) and -400F

(-400C) for 24 hr. period over a 2 week duration. At the end of this accelerated aging test, the sample cables were then subjected to the fire test 1

, described in Paragraph 4.4 and the high potential test (see Paragraph 4.3).

The results of these tests were satisfactory, f- 4.8 A coated cable section was subjected to an ampacity test prior to which a Hewlett-Packard No. hp-0837-0614 thermistor was imbedded in the base

' copper conductor. The cable was then subjected to its rated current carrying capacity of 285 amperes (according to the National Electrical Code) until the temperature indicated by the thermistor had stabilized, in approximately one hour at 1350F (570C). This is well below the 900C maximum temperature rating of the cable insulation; therefore, no electrical derating is necessary 1

, when a cable is sprayed with Thermalastic 83 according to the manufacturer's recommendations.

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FACIORY MUTUAL RE SE ARCH COOPOR A TION Page 4 OJ0A4.AF 4.9 A sample cable length coated with Thermalastic 83 has been under actual weather exposure test conditions for approximately four months. The coated cable sample appears satisfactory at this time; however, continued observation of this sample is planned to supplement present field experience.  :

V CONCLUSION Fire-Stop Systems Thermalastic 83 fire retardant cable coating meets  ;

Factory Mutual approval requirements. Approval is effective when the Approval Agreement is signed and returned to Factory Mutual.

EXAMINATION AND TESTS BY: W. Pelrine and D. C. Smith REPORT BY: REVIEWED BY:

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' David C. Smith D. R. Knight' \ { " J Asst. Mgr., Fuels Section Manager, Fuels %ction DCS/pj ORICINAL TEST DATA: Test Notebook 83-44 i ~

ATTACHMENTS: Product Data Sheet

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FIRE-STOP SYSTEMS rr

,. Thermalastic 83" e DATA SHEET g' PRODUCT DESCRIPTION considered permanent. THERMA.

THERMAL ASTIC 83'" is a single LASTIC 83* coating can be removed consistency. If thinned, material may

,o package, water based, high solids, fire lose its thixotropic (no drip) properties.

t from the cable where necessary.

L protection elastomer coating- SPECIFICATIONS AND THERMALASTIC 83* coating is APPLICATION PHYSICAL DATA designed to prevent propagation of fire THERMALASTIC 83* can be applied fe in grouped electrical cables and with air atomized or airtess spray Average Solids Content of Material:

69 %

protect electrical cables from fire. equipment. It can also be applied by L Constant service temperature tange ls brush, trowel or hand gloving Color: White from .30*F (-34*C) to 195'F (91*C) techniques. Manufacturer should be

.., after curing. Weight: Per Gallon (3.78 lietres),

consulted for recommendations on 11.5 lbs. (5.2 kg)

THERMALASTIC 83* coating contains exact equipment specifications.

no asbestos or chlorinated hydro. THERMALASTIC 83* has good Per 5 Galton (18.92 lietres)

Pail. 61 1bs. (27.7 kg) carbons, and meets all applicable adhesive properties and will readily Elongation: 150%

'r OSHA and EPA regulations. THERMA- adhere to vertical or overhead LASTIC 83* will not support swfaces. THERMALASTIC 83* may be impact Resistance: Excellent combustion. applied within a temperature range of 8

Vibration Resistance: Excellent RECOMMENDED USES 40'F (4* C) to 100'F (3 8

• C).

THERMALASTIC 83* should be pre- Thermal Shock: Freeze thaw cycling, At approximately 1/16 inch (1.6mm) conditioned to a minimum of 50'F consis sev n c les of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> y dry film thickness, THERMALASTIC (10'C) for 24 to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> prior t .p .

63* will halt fire spread in grouped spraying to achieve optimum results, 40

• C). Samples retained original se Clectrical cables and protect cables Best spray results are obtained by appearance-from fire exposure. Protection en. applying a thin (tog) coat and allowing

~ durance from fire exposure will Salt Water immersion: Thirty cycles of this to dry to the touch before building eight hours being immersed in 150*F depend on coating thickness and up to the recommended 1/8 inch (3.2

'p, greater thickness will provide more mm) wet thickness which, when (66*C) salt water and 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> of endurance. No electrical derating of drying. Sample showed no completely dry, will be approximately deterioration, j the cables is necessary at 1/16 inch 1/16 inch (1.6 mm) thick.

(1.6 mm) dry film thickness of coating.

Application should be performed by THERMALASTIC 83* provides a an experienced FIRE-STOP SYSTEMS RECOMMENDED FILM

.-1 barrier that has excellent resistance to water, fire, corrosion, toxic or corrosive factory approved applicator. THICKNESS-gasses and fuels or lubricants. THERMALASTIC 83* coating is nor- Approk.1/16 inch (1.6 mm) Dry.

. e' mally dry to the touch in 10 minutes to 4 Approx.1/8 inch (3.2 mm) Wet.

COVERAGr. hours. This, of course, depends upon

.J THERMALASTIC 83 *, applied, at the coating thickness, temperature and SHELF LIFE: 24 months minimum relative humidity. Curing is normally when stored between 40*F and 90'F' cpproximately 1/8 inch (3.2 mm) wet r,

film thickness, will be approximately complete in 3 to 5 days. After curing, Coverage: (per Gallon) 12 sq. ft. (1.1 1/16 inch (1.6 mm) thick (dry) and the coating remains very pliable and m2) of cable tray at approx.1/8 inch s individual cables may be removed from (32 mm) wet c verage is approximately 12 square feet (1,1m2) of cable tray surface per a grouping,if necessary;any damaged Consistency: Thixotropic a, gaffon. portions of the protective coating may be repaired by spraying, brushing or Packaging: 5 Gallon containers.

s SURFACE PREPARATION gioving. 18.92 lietres No surface preparation is normally Clean-up is accomplished with clean Flash Point: (Pensky-Martens Closed

, required. THERMALASTIC 83* has water. Cup) cdequate adhesion to all types of cable None a Uckets, without any surface prepara- THINNING tion, and application may be Material is supplied at spraying

] KEEP FROM FREEZING:

j TMERM ALASTIC 83', hke most waterbase coatings. can conduct electncity untilit ui is thoroughty dry Appropriate ca t on sh encountered enclude, but are not hmeted to, open buss ducts.ransformer .

u i ycable potheads.

personnel. Harards bushengs that may be esposed L

THE7.MALASTIC 83* whech are irnportant factors en insure that your results will be the same as those ,desenbed.

etsendations performance. Smco for the use and apphcation ave control over the use and apphcation. it cannot of FIRE S f

a deu tive by our laboratory FIRE.STOPSYSTEMS shall THERMALASTIC 83* .

, r not be hable for as tryury is provedloss to be or dama l onsequential, ansmg out of the use or enabilety to use L

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