Document 3QQxpz54EJy0NrNRO56m2vykJ
CAB CORD
This is a specialty product, designed for drop light cords in steam engine cabs.
Rubber covered wire in this application had only a short life, the high temperatures vulcaniz ing it rapidly and the constant motion and vibration cracking it and oausing mechanical and then electri cal failure.
Cab Cord is made by twisting two conductors of plain fixture wire (see "Fixture Wire" bulletin) together and placing a heavy asbestos braid overall. The impregnation throughout is the black, flameproof and moistureproof compound.
Being permanently flexible even under high temperature conditions, ROCEBESTOS cab cord gives far longer service than any type of material that has been used and almost all railroads in the country are now buying it.
Iron and steel mills use it for extension cords in trouble lamps when the men go into furnaces to clean them sometimes before they are cooled.
For severe service the individual conductors are insulated with a combination of varnished cambric tapes and felted walls, then twisted and braided over all*
This V.C. type cab cord is used instead of plain cab cord for lighting circuits on locomotives if a train control system is installed. If single insulated wires afe preferred, A.V.C. cable or Table E material (Switchboard Wires and Cables bulletin) should be recommended.
RBB 00379
HEATING UNITS
These are sold to raanufacturers of low wattage heating devices such as
/ Curling irons Soldering irons Hair wavers Hot water bottle heaters Immersion heaters
Necktie pressers Incubators, etc*
The units are made to specification as to physi cal size, wattage, etc* They consist of a number of
asbestos yarns bunched together to form a core with resistance wire*wound helically over the core so that the turns do not touch. This is then cut into prede termined lengths* Plain copper lead wires are then attached to the ends of the short lengths of element
by a mechanical connection, forming a continuous link arrangement from which the name "sausage element" is
derived. This is then insulated in a continuous length and when out in the middle of each lead wire a complete
heating unit with leads, ready for connections, results.
It looks like this:
^hmcWncW iunc+ionm --_
Sj t______________D
( euf >tr --^t*
(ip ctn+ar)
copper*iead**
HEATING ELEMENT
This is made the same way except it is not made in
units but is nimished in quantity and out by the appli
ance mnufaoturer to his own requirements.
*
It's used in
inoubators heater pads, etc. permanent wave ovens wafLe irons
percolators
Marcel wavers toy flatirons radio resistor devices
RBB 00380
CWOO g g y
coj iU D 0* 0-
CL
0. *
CO
0H 0
CO
Li 1
0*.1
8-
(C
'Mr*
MULTI-CONDUCTOR CONTROL CABLE
This is a new product with us in the form shown opposite; that is, new in the sense that we have not supplied the combination before/
But the insulation of the individual con ductors is our Table E type with the exception of the cotton instead of the asbestos outer braid.
Central stations are the principal pros pects for this type of material as they have been using rubber insulated control cables in boiler room circuits.
The illustration shows a white asbestos outer braid but the cable can be taped before ap plication of the braid and the braid then finished with the standard black compound.
sue**-
ROCKBESTOS -the asbestos covered wire
MOTION PICTURE CABLE
SM. 10. 1920
RBB 00384
Rockbestos
Extra Flexible Motion Picture and Arc Light Cable
OCKBESTOS motion picture cable combines all of the characteristics which are neces
R sary for supplying power to projection machines, spot, flood and ocher arc lighting equip ment. Ic will not deteriorate with age, burn or communicate fire even if it be subjected to contact w ith an electric arc. Extreme flexibility is of utmost importance so that no matter what position the apparatus is placed in, the cable w ill conform w ithout any tendency to destroy the adjustment. The copper conductor is composed of a large number of fine copper wires, thoroughly annealed and of uniform and extreme softness stranded together into a rope like structure resulting in this necessary flexibility.
ROCKBESTOS insulation is applied to the conductor so as to produce a continuous felted wall of uniform thickness, saturated with a special chemically neutral compound, which has the necessary dielectric and mechanical strength and will remain permanently flexible. Over this insulation a closely woven braid of asbestos is applied, saturated with a white flame proof compound which provides a tough smooth outer surface which will resist abrasion, and will not flake off.
J
PROJECTION ROOM
SUN ARCS We manufacture asbestos insulated wires and cables for every purpose. Descriptive bulletins on request.
RBB 00385
MOTION PICTTJRB CABLE
As the name indicates, the principal use for this type of material is on projectors, spot lights, sun arcs and similar apparatus, where the fire hazard is high.
This type of apparatus requires an extremely flexible conductor and a correspondingly flexible, flameproof insulation.
A central station engineer who bought our Table I wire for his swinging switchboard panels was using a flexible lamp cord (rubber insulation with cotton braid) for the hinge connections between the termin al strip in the swinging panel and the one on the wall.
We suggested he use motion picture cable of the proper size as it was more than sufficiently flexible for his needs and also fully flameproof, the ideal material for the application.
See photograph entitled "ROCEBESTOS Wired Board Toronto Hydro-Electric System11.
Practically all manufacturers of motion picture . apparatus in this country equip their products with or recommend the use of ROCnBESTOS motion picture cable.^
Other usest
Connections on blueprint machines from the arc lamp to the terminal box.
RBB 00386
Rockbestos Extra Flexible Motion Picture Cable
National Electric Code Standard Construction Specification
Size 8&S Gauge
2
4 0 3 10 12 14 lo 13
Carrying capacity amperes
Stranding:
Thickness wall mils
Outer covering
125 7 x 7 X 59/36 40
90 7 x 7 x 37/36 40
70
1050/36
40
50
665/36
35
30
413/36
35
25
65/30
30
20
41/30
30
10
26/30
25
5
16 30
25
*3
12 i9 ss
9V
E
9
O. D.
.535 .440 .385 .320 .275 .235 .225 .210 .195
Weight in lbs. per M. ft.
Standard shipping lengths in feet coils
303 150 195 250 130 500 81 500
58 500 41 1000 31 1000 25 1000 20 1000
Finished 0. D. given above is nominal. A tolerance of plus or minus 5% is necessary on ac count of variations in process of manufacture.
Rockbestos Motion Picture Cable is approved by Underwriters Laboratories, Inc.
MOTION PICTURE PROJECTORS
RBB 00387
RBB 00388
ROCKBESTO$
-the asbestos covered wire
MAG
WIRE
RBB 00389
i
Rockbestos Magnet Wire
ROCKBESTOS Magnet Wire is made in ail standard sizes of round, square and rectangular cross section. The dielectric and mechanical strength of Rock bestos insulation will meet all requirements of service and coil winding and will not fail under extreme heat conditions even up to the fusing point of copper.
ROCKBESTOS insulation will withstand fumes of practically ail acids and this makes its use essential in all coils operating under these conditions.
The conductor is thoroughly annealed copper of uniform and extreme softness and of 98.5% electrical conductivity, according to Matthiesen s Stan dard. It is carefully inspected for accuracy of dimensions.
The insulation is pure long fibred asbestos, commercially free from me tallic oxides, thoroughly separated, carded and spun into roving which is wound uniformly upon the conductor and then saturated with a special chemically neutral compound, and compressed into a continuous wall of insulation of approximately the same thickness as double cotton covering.
Round Copper Magnet Wire is furnished in either white, black or P. N. (amber) finish. Rectangular and square are furnished in either white or black finish.
The finished wire may be elongated 10% without harm to the Rockbestos insulation, thus allowing for bends necessary in the manufacture of coils.
WV manufacture asbestos insulated wires and cables for every purpose. Descriptive bulletins on request.
RBB 00390
MAGNET WIRE
This is made in several finishes; black, white, P.N. and B.F.
In selling the material the best method is to attempt to prescribe a finish for the conditions under which the wire will be used.
The black finish is moistureproof and flameproof and if a motor is to be subjected to considerable moist ure, spray, acid fumes, etc. this would be the type of finish to recommend.
The white finish will withstand high temperatures such as would be generated in the windings of a motor which was suddenly overloaded, an elevator motor, for instance.
If the wire will be subject to considerable abra sion during installation the inssulation should be tough enough to withstand this abuse and not tear and the P.N* finish, an air drying varnish finish, is the finish to prescribe.
The B.F. is similar to P.N, but even tougher, tha asbestos being impregnated with a special heatproof, moistureproof and acidproof insulating cement which is later baked at a high temperature.
Asbestos insulated magnet wire is used in
brake coils armatures field coils lifting magnets relays, etc. etc. solenoids of electrically
operated track switches (tramway)
circuit breaker coils small reactors
There is a process now in development which will enable us to produce asbestos insulated magnet wire in sizes #14 B&S gauge and smaller with outside diameters no larger than double cotton covered wire.
RBB 00391
Magnet Wire continued An entirely new field of applications to small motors and other devices will probably result es pecially if the cost of the asbestos insulated wire is the same as or only a little in excess of the cotton corered wire.
RBB 00392
Round Copper Magnet Wire
Size B. & S. Gauge
0000 000 00 0 1
1
3 4 5 6
7
8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
BARE WIRE
i
Diameter Inches
.460 .410 .365 .325 .289
.258 .229 .204 .182 .162 .144 .129 .114 .102 .091 .081 .072 .064 .057 .051 .045 .040 .036 .032 .029 .025 .023 .020 .018 .016 .014 .013
.
Area Circular Mils
211600 167800 133100 105500 83690 66370 52640 41740 33100 26250 20820
16510 13090 10380
8230 6530 5178 4107 3257 2583 2048 1624 1288 1022
810 642 509 404 320 254 202 160
*
,
] ! :
i : : i : ` : ; i ; [ !
; j 1
ROCKBESTOS COVERED WIRE
Insulation Thickness
Mils
Approximate Diameter over Insulation in
Inches
Approximate Pounds
per 1000 ft.
10.5 .481 o47
10.5 .431 513
10.5
.386
409
10.5
.346
325
10.5
.310
253
10.5
.279
205
10.5
.250
163
10.5 .225 130
10.0 .202 103
9.0
.180
82
9.0 .162 65
8.0 .145 52
7.0
.128
41
6.5 .115 33
6.5
.104
26
6.5 .094 21
6.0 .084 16
6.0
.076
13
6.0
.069
10.4
6.0 .063
8.3
6.0 .057
6.6
6.0 .052
5.3
6.0 .048
4.2
6.0 .044
3.4
6.5 .042
2.80
6.5 .039 2.28
7.0 .037
1.86
7.0 .034
1.51
8.0 .034
1.29
8.5 .033
1.09
9.5 .033
.95
10.0 .033
.83
Rockbestos Round Magnet Wire is furnished on reels with standard full reel quantities as follows:
0000 -- 13 B. & S. Gauge 200 lbs. 14 -- 28 B. & S. Gauge 50 lbs.
Rockbestos Round Magnet Wire is furnished in jet-black, snow-white and P. N. finish. This latter finish is our more recent development and is recommended in sizes from 28 to 6 where an exceptionally tough outer finish is desired.
Rockbestos Magnet Wire is unequalled for use in manufacture of armature and series and shunt coils for railway, mining, mill, and general industrial motors, for coils in lifting magnets, for brake coils and ail types of electro-magnetic windings, solenoid coils, welding transformers -- wherever windings are subject to temperature conditions.
RBB 00393
Rectangular and Square Magnet Wire
Since Rectangular and Square Magnet Wire can be made in so many different sizes and with so many different thicknesses of insulation, it becomes impractical to completely tabulate them all. The following table lists the nominal difference between the width or thickness of Rockbestos insulated conductor and corresponding dimensions of bare conductor.
Bare Copper Width
in Inches
Bare Copper Thickness in Inches
.0 to .020 .021 to .040 .041 to .050 .051 to .080 ,081 to .095 .096 to .103 .104 to.110 111 to .120 .121 to .135 .136 to .145 . 146 to . 160 .161 to .175 .176 to .195 .196 to .215 .216 to .240 .241 to .270
.0 .0% .121 .146 .176 .241 .301 i .351
To .095
To .120
To .145
To .175
To .240
To .300
!
.350
'
To .500
Nominal difference between width or thickness of insulated conductor, and corresponding dimension of bare conductor -- Given in inches.
.014 .016 .017 .017 .018 .019 1 .020 | .021
.013 .015 .016 .016 .017 .018 ; .oi9 1 .020
.012 .014 .015 .015
016 .017 i .018 i .019
.011
.013
.014
.014
.015
.016 ! .016
.017
.012 .013 .014 .014 .015 .016 ! .017 .018
.013 .014 .015 .016 .017 .018 ` .019
.014 .015 .016 .017 .018 .019 .020
.015 .016 .017 .018 .019 .020 .021
.016 .018 .019 .020 1 .021 1 .022
.017 .018
019 .021
.022 i .023
.018 .020 .021 1 .022 i .023 .019 .020 .022 .023 1 .024
.020 .022 .023 .024
. .021 .023 i .024 ! .025
.022 .023 ' .024 : 026
.023 .025 .026
1
Rockbestos Square and Rectangular Magnet Wire is furnished in standard full reel quan tities of 200 lbs.
Rockbestos Square and Rectangular Magnet Wire is furnished in either snow-white or jetblack finish.
Offering for coil winding purposes a greater effective cross section of copper than round wire, Rectangular Rockbestos Magnet Wire finds its principal use in large industrial, railway and mine motors, synchronous motors and rotary converters, electric furnace windings and similar heavy capacity work.
RBB 00394
CURLING IRON CORD
Manufacturers of these appliances insist on an extremely flexible and lightweight, small diameter cord*
Heretofore two rubber insulated tinsel conductors hare been twisted loosely together and a braid placed over all. This construction is not approved by the Underwriters.
We have developed a cord which is in real ity a lightweight heater cord with a tinsel conduc tor which now gives the curling iron manufacturer everything he wants in the cord and also a means of gaining approval for his device.
RBB 00395
ROCKBESTOS
-the asbestos covered wire
HEATER CORD
ROCKBESTOS PRODUCTS
CO R P O R A T !O N
NEW HAVEN. CONN.
8942 Grand Coatral Term. Bid*. Now York
903 dark Bid*. Pittaburg. Pa.
Madiaon Terminal Bldg. Chicago. III.
On tho Pacific Coaat C. Dost Slaughter
APRIL I, 1929
RBB 00396
A
Rockbestos Heater Cord
OCKBESTOS "3000" heater cord represents, what we believe to be, the finest heater
R cord that can be manufactured. Nothing but the choicest of materials are used and each manufacturing detail is subjected to continual inspection. It has an extra flexible conductor and its construction is such that it will not kink in ordinary service on any kind of heating appliances, even those which are in motion, when in use. It meets or exceeds the requirements of the National Electric Code in all respects and every coil bears the Underwriters' label of approval. Underwriters' Laboratories approval requires an average performance of not less than 1000 cycles on their standard heater cord endurance machine. Rockbestos "3000" will average over 3000 cycles.
The conductor is composed of the proper number of wires each No. 34 B & S gauge, cotton served and insulated with rubber over which is an application of Rockbestos roving which forms a continuous heat insulating layer of the most efficient type which protects the rubber from external heat and gives maximum durability and flexibility. Duplex cord is two such conductors twisted together with a short lay; then covered with a soft or glazed cotton, rayon, or combination of cotton and rayon braid. Twisted pair cord is two conductors individually braided and twisted together. Our standard braiding pattern is glazed cotton with rayon striper as illustrated on the opposite page, but can be furnished in any desired pattern and colors.
ROCKBESTOS "3000" heavy duty heater cord is regular "3000" with the exception of the outer covering which is a heavy cotton, increasing its resistance to abrasion. Com monly used on commercial appliances w hich are in constant use such as laundry irons, restau rant percolators, toasters, waffle irons, etc.
Rockbestos "X" heater cord is of the same general construction as Rockbestos "3000" except the conductor which is slightly less flexible; the individual wires being No. 30 B & S gauge instead of No. 34. It is designed especially for heating appliances that are not in motion when in use. It complies fully with the requirements of the National Electric Code and bears the Underwriters' label of approval.
Triplex heater cord is made with the asbestos on each conductor of a different color, the three conductors tripled together and covered with a cotton or rayon braid.
manufacture asbestos insulated wires and cables for every purpose. Descriptive bulletins on request.
RBB 00397
HEATER CORD
Heater Cord has of course the one general appli cation to appliances which produce heat in their oper ation.
It1s so easy to overlook some of these, how ever. that we're putting below a list of some of the appliances for which we have* sold the cord.
Incidentally a point of interest is that in the United States we sell approximately 1/3 of the cord consumed and supply about 65# of appliance manufactur ers part or all of their cord requirements.
Toasters Flat irons Percolators Table stoves Grills Sandwich toasters Egg boilers Heater pads Hair wavers Hot water bottle warmers Milk bottle warmers Waffle irons Soldering irons Vail outlet ranges and stoves Electric fireless cookers Room heaters Immersion heaters Bacon broilers
RBB 00398
ROCKBESTOS
-the asbestos covered, wire
BRAIDING PATTERNS OF HEATER CORDS for all types of Electrical Heating Appliances
1A M
BQ
C
D
H
j
These illustrations show the most commonly used patterns. Other combinations can be made on request.
Any color combination desired can be furnished.
Approved by Underwriters Laboratories, Inc.
ROCKBESTOS PRODUCTS
CORFORAT I ON
NEW HAVEN.
--
CONN.
RBB 00399
Rockhestos Heater Cord
National Electric Code Type H
Approved by Underwriters' Laboratories. Inc.
Sire B&S Gauge
No.
14 16 17 13
Rockbestos "3000" Conductor
Rockbestos "X" Conductor
No. Wires
B&SGauge of each wire
No. Wires
B & S Gauge of each wire
104 34
41
30
65 34 26 30
52 34 20 30
41 34 16 30
Pounds per 1000 ft.
Rayon
46 34 28 23
Cotton
49 36 30 25
Allowable carrying Capacity(Arnps.)
20 10 ~XA 5
Standard packing two 500 foot coils in one carton. Can be furnished on 12' or 24' wooden reels if desired or 250 and 500 feet on fibre spools.
Can also be furnished cut to any desired lengths, with or without ends stripped and tied.
RBB 00400
RBB 00401
ROCKBESTOS -the asbestos covered wive FIXTURE WIRE
APRIL 1, 1929
RBB 00402
Rockbestos Fixture Wire
i
CDOCKBESTOS Fixture Wire is made for wiring all types of lighting fixtures and commercial units. It is manufactured of the best materials and the
workmanship is of the highest quality. Rockbestos insulation provides maximum protection against failure from overheating, which is of common occurrence where other types of insulation are used. Rockbestos insulation will not bum and cannot communicate fire to adjacent combustible materials. It will retain its flexibility and has the necessary dielectric and mechanical strength to insure long life. It is approved by the Underwriters" Laboratories, Inc. and its use is insisted upon by Electrical Inspectors in a number of districts.
The stranded conductor is thoroughly annealed copper of uniform and ex treme softness and of 98.5^ electrical conductivity, according to Matthiesen's Standard. It is carefully inspected for accuracy of dimensions.
The insulation is pure long fibred asbestos thoroughly separated, carded and spun into roving which is wound uniformly upon the conductor in two coats, applied in opposite directions and then saturated with a special chemically neutral compound and compressed into a continuous wall of insulation of the proper thickness. It can be furnished both coats white or both coats black or with the inner coat black and the outer coat white or colored. When white or colored outer finish is desired we recommend that the inner coat be black to provide greater moisture resistance. Fixture wire having both coats white or colored is recommended for use under conditions of extreme heat and no moisture such as internal wiring of heating appliances, pyrometer leads, etc.
For decorative purposes the asbestos insulation may be covered with a rayon or cotton braid in any desired color or combination of colors and is made in one, two, or three conductors, individually braided or under one cover. Three conductor fixture wire with a braid overall is sometimes called kitchen unit cord.
To comply with the requirements of the National Electric Code for identi fication of grounded conductor, plain fixture wire with white outer coat is pro vided; for braided conductor one or more threads of contrasting colors are woven into the braid.
Rockbestos fixture wire can be furnished with solid conductor and with a heavier insulating wall to suit unusual requirements.
We manufacture asbestos insulated wires and cables for every purpose. Descriptive bulletins on request.
rBB 00403
Fixture Tire
This article, while given a definite name has a variety of uses. As a fixture wire, however, it is being used in increasing quantities on fixtures where at first thought it would seem that a heat re sisting insulation would not be needed.
Small fixtures particularly those equipped with gas filled lamps show surprisingly high socket temperatures which fully warrant the use of an as bestos insulated wire. See the report entitled "Lamps and their Heating Effects" at the rear of "test reports" section.
Efforts are being made in several cities in this country to require the use of a "heat resist ing" wire for all lighting fixtures using lamps con suming 50 watts and over. In this respect the Nation al Electric Code goes only to the extent of stating that wherever temperatures exceed 120 F. a "heat re sisting insulation" is required. The Underwriters* Laboratories requirements for approval, however, are that when temperatures exceed 194 F. "an asbestos insulated wire" is required.
Considerable educational work is being done toward increasing the use of asbestos insulated fix ture wire on all fixtures and its consumption for this purpose is definitely on the increase.
Other uses are:
Hair waving machines Radio power units and sets (in prox
imity to power and rectifying tubes (valves) which generate considerable heat.) Electric fan leads from base to motor Hinge connections in household waffle irons, sandwich toasters, etc.
RBB 00404
Rockbestos Fixture Wire
Construction Specifications
Fixture Wire -- Plain
Fixture Wire -- Rayon or Cotton braid
Sire B. &. S. Gauge
10 12 14 16 18
Stranding
104/30 65/30 41/30 26/30 16/30
35 32 32 32 32
jJ f
i-
O. D. Plain
.195 .160 .140 .125
.no
* O. D.
Cotton Covered
* O. D.
Rayon Covered
.215 .180 .160 .145 .130
.210 .175 .155 .140 .125
Plain
Pounds per 1CC0 feet
Cotton
Rayon
41 27 18 12.2
8.5
44 29 20 14.2 10.5
43
23
19
13.2
9.5
Rockbestos Fixture Wire conforms to the latest specifications of the Underwriters Laboratories, Inc. and bears their approval label.
Standard package 1000 foot coils. Can be furnished on fibre spools. ROCKBESTOS FIXTURE WIRE is also used in wiring of devices where permanent flexibility and heat resisting insulation is required, such as permanent waving machines, heat ing appliances, show case lighting units, therapeutic devices, etc.
Kitchen Unit Cord Kitchen Unit Cord meets the need for a safe and satisfactory three-conductor wire for kitchen units, having combination convenience outlet and switch, to which electric appliances may be attached.
Finished O. D. given above in nominal. A tolerance of plus or minus 5% is necessary on account of variations in process of manufacture.
RBB 00405
I
II
RBB 00406
ROCKBESTOS
-the asbestos covered wire
RANGE WIRES
for wiring
Electric Ranges Hot Plates
Pyrometers
Table Stoves Electric Ovens
RBB 00407
Rockbestos Range Wires
ELECTRIC RANGES are coming into general use more rapidly every day, which neces sitates careful selection of materials on the part of the manufacturer. That ROCKBESTOS is used by most range manufacturers is an acknowledgment of its high quality.
MISCELLANEOUS other uses for ROCKBESTOS Range Wires and Cables are listed on the cover of this bulletin.
SPECIFICATIONS covering construction and testing of our All Asbestos Insulated Wires and Cables are published in our Rockbestos Wires and Cables Bulletin. The construction, briefly, is as follows: CONDUCTOR. May be Copper, .Monel metal. Nickel or other alloys, bare or tinned, solid or stranded. INSULATION. Is all asbestos, applied by the Rockbestos felted process, providing ample dielectric and mechanical strength. Can be impregnated with white flameproof compound which can be used where no moisture is encountered, but we strongly recommend black impregnation which is flameproof and moisture resistant. The compound in the insulation does not affect the color of the outside braid. COVERING. A heavy asbestos braid approximately 45 mils in thickness finished with white or colored flameproof or black flameproof and moisture resistant compound. Stranded and flexible conductors can be furnished with the same insulation as specified for solid. Two or more conductors either solid or stranded can be cabled together with or without a braid over all.
Where additional dielectric strength or moisture resistant qualities are desired, we can furnish a varnished cambric and asbestos insulated combination, standard construction for solid conductor being two layers of varnished cambric applied next to the conductor and then a felted wail of asbestos and an asbestos braid. For wall thicknesses, diameters and other information see following tables.
For applications, requiring the smaller sizes, where there is danger of conducted heat from heating elements, etc. w hich might injure the varnished cambric, we can furnish the con struction with the felted wall of asbestos next to the conductor so as to insulate the varnished cambric against overheating.
Allowable carrying capacities for Monel metal and nickel conductors are not defined in the National Electric Code but general practice in selecting sizes is to use a conductor two B & S gauge sizes heavier than the necessary copper conductor. This brings about conductor temperatures higher than would be allowable for copper, but the characteristics of Monel metal and nickel conductors enable them to operate without deterioration under these con ditions.
'X'e manufacture asbestos insulated wires and cables for every purpose. Descriptive bulletins on request.
RBB 00408
RANGE WIRE
This bulletin gives the range manufac turer the information he needs about our mater ial for his requirements.
The fly-leaf opposite Table I in "ROCKBESTOS Wires and Cables" bulletin gives other uses for this same product.
The combination asbestos and varnished cambric insulation shown is used principally by the range maker on products destined for export where high humidity is prevalent and certain in sulation resistance tests are to be met. USES:
All circuits of electric ranges, hot plates, and stationary room heaters.
RBB 00409
Range Wire
All Asbestos Insulation
Solid
Felted
Copper Asbestos
Conductor
Asbestos Braid
Size A. W. G. (B. Si S.)
BARE
8 10 12 14 16 18
SOLID CONDUCTOR
600 VOLT SERVICE
Bare Dia.
.128 .102 .081 .064 .051 .040
Felted Wall Thickness Mils
Braid Thickness
Mils
35 45 35 45 30 45 30 45 25 45 25 45
Approx. O. D. Finished
.289 .262 .231 .214 .191 .180
Pounds
Standard Shipping Length (Maximum in feet)
ftSft.
Coils
Reels
75 500 1000
55 500 1500
40
1000
2000
30
1000
2500
25
1000
3000
20
1000
3000
Varnished Cambric and Asbestos Insulation
Solid
Varnished Felted Asbestos Braid
Copper Cambric Asbestos
Conductor
'V`^r-\-yr
Size A. W. C. (B. &S.)
BARE
Bare Dia.
8 .128 10 .102 12 .081 14 .064 16 .051 IS .040
1ooA
r
V. C.
2-.005" 2-005' 2-.005"
2-.005" 2-.005'
SOLID CONDUCTOR
Felted Wall Thick-
Mils
Braid Thick
ness Mils
Approx. 6. D.
Finished
Pounds per
M ft.
Standard Shipping Length (Maximum in feet
Coils
Reels
20 45 .233 75
500
20 45 .257 55
500
20 45 .236 40
1000
20 45 .219 30
1000
20 45 .206 25 1000
20 45 .195 20
1000
1000 1500 2000 2500 3000 3000
Finished O. D. given above is nominal. A tolerance of plus or minus 5% is necessary on account
of variations in process of manufacture.
'
RBB 00410
RBB 00411
ROCKBESTOS -the asbestos covered wire
ROCKBESTOS A. V. C. CABLES
Permanently Flexible
unaffected by
Heat, Moisture, Acid, Flame, Oil, Gas
APRIL 1, 1929
RBB 00412
Rockbestos A. V. C. Cables
The construction of these cables has been developed especially for wiring mine locomotives and mining machines, and for circuits in and about mines or other locations where heat and moisture are encountered.
The conductors are of flexible stranding made up of thoroughly annealed copper wires, tinned and laid up as shown in the table.
The insulation consists first of a layer of felted asbestos applied in the form of untwisted roving, thoroughly saturated with moisture proof compound and compressed to form a compact, uniform wall of thickness shown in the table. Over this felted wall three layers of .006' thick high grade varnished cambric tape are wrapped in such a way that each layer laps about one quarter the width of the tape and the joints in the successive layers are staggered to provide maxi mum insulation resistance. Petrolatum is applied between layers of cambric to provide lubrication and moisture resistance.
Over the varnished cambric another felted asbestos wall, of thickness shown, is applied in the manner described above.
An outer braid of heavy asbestos yam is woven closely over the last felted layer and thoroughly impregnated with black moisture proof and flame proof compound to produce a smooth rugged finish.
This construction provides an insulation of ample dielectric strength, maxi mum insulation resistance and greatest flexibility that will retain its original characteristics indefinitely. It is not affected by temperatures met in mining service, nor will it deteriorate in the presence of moisture, coal dust and oil as encountered in the operation of most mining machinery.
Complete test data substantiating the above will be furnished on request.
RBB 00413
Rookbestos Data Sheet #8
iVC Cables Jan. 10, 1930
Insert opposite A.V.C. Cables . Bulletin
ihe specially flexible stranded tinned copper
cable with the A.V.C. insulation is the unique result
of an interesting incident.
".
A large manufacturer of mining equipment - loco motives, coal cutters, etc. - had experienced consid
erable trouble with insulation failures in one type of locomotives after they had been in service for"a short time*
They asked us if we made a cable that would per
haps do away with the difficulty. At the time we made only asbestos insulated cables.
One of our engineers went to the tfest Virginia coal fields where several of these locomotives in ser vice in a mine had been giving trouble and inspected the service conditions first hand.
The oables in use at the time passed through the
iron housing of the motor and thus were effectively
grounded. Due to coal dust, oil, moisture and heat
attacking the insulation of the wires, frequent break
downs occurred at this point.
'
One .experience with rubber insulated cables had been most eye opening. Sven though the cables came out from the hermetically sealed motor compartment through stuffing boxes, they-had caught fire on the inside and it had traveled along the cables through the stuffing boxes*.to the outside, thus presenting a most serious.hazdrd especially in a gaseous mine.
It was decided that our asbestos insulated cable would servd .if varnished cambric could be combined with it in .order to insure a continuously high insula
tion resistance under the service conditions involved.
The test is described in detail in the report entitled Report of Test on Mining Machine Cable11 in the "test reports" section.
The final design was submitted to the company (Jeffrey Manufacturing Co. - Columbus, Ohio.) tested
RBB 00414
A.V.C. CABLES continued.
by them and finally adopted as standard for motor lead w orlc
An experience with the A.V.C. Cable fully justi fies the Jeffrey company's action in standardizing on it. A short circuit occurred in the motor compartment of a locomotive in service and a fire started. But con trary to the experience related above where the rubber insulated cables burned up, the A.V.C. Cable not only did not transmit the flame to the outside, but the flame did not even burn up to the stuffing boxes on the in side*
The Jeffrey Company has just recently staadard,i2ed on A.V.C. Cable for motor leads on all equipment.
Table C and E insulations were, of oourse, adaptations of this original A.V.C. Cable design.
Other uses: All electrically operated mine machinery. ' itine locomotives Uriercutters, etc Headlight wiring where train con trol system is used.
RBB 00415
Construction Specifications
Rockbestos A. V. C. Cables
Flexible Felted Varnished Tinned As- Cambric <*opper bestos
Conductor
FVIted As-
bestoa
Asbestos Braid .OlS* Thick
Size Cond.
Stranding
First Felted Wall
Mils
v. c.
Second Felted Wall Mils
Finished O. D. m
Pounds per M feet
Standard . shipping lengths (maximum in ft.) Coils Reels
500.000 C. M. 450.000 C. M.
427. 61 x 7 1.03387) 20 3 -- .006" 45 1.184 1828
427. 61x7 (.03195) 20 3 -- .006" 45
1.133
1636
7 50 750
400.000 C. M. 350.000 C. M.
427, 61 x 7 (.03016) 20 3 -- .006" 45 427. 61x7 (.02846) 20 3 -- .006"- 45
1.084 1.038
1475 1330
1000 1000
500.000 C. M.
427. 61x7 (.0269)
20 3 -- .006" 45
250.000 C. M.
250. 37 x 7 (.0320)
20 3 -- .006" 45
0000 B Sc S Ga. 250. 37 x 7 (.02846) 15 3 -- .006" 25
.995 1194 .941 1049 .808 810
1000
won
1000
000
259, 37x7 (.02535) 15 3 -- .006" 25 .742 657
1500
00
259. 37 x 7 (.0226) 15 3 -- .006" 25 .682 527
1500
0
259. 37 x 7 (.0201) 15 3 -- .006" 25 .637 441
1 SCO
l
133. 19x7 (.0253) 15 3 -- .006" 25 .590 364
1000
2
133, 19 x 7 (.0226) 10 3 -- .006" 15 .520 282
1000
3
133, 19x7 (.0201) 10 3 -- .006" 15 .482 235
1000
4
133. 19x7 (.0179) 10 3 -- .006" 15 .450 192
2000
5
49. 7x7 (.0253) 10 3 -- .006" 15 .408 150
2500
6 49. 7x7 (.0226) 10 3 -- .006" 15 .386 123 500 2500
8
49, 7x7 (.0179)
10 3 -- .006"
15
.342
91 500 2500
10
37 /.01689
10 3 -- .006" 15
.298
65 500 1000
12
65 /.010
10 3 -- .006" 15
.280
49 1000
1000
14
41 ,'.010
10 3 -- .006" 15
.260
39 10C0
1000
j "Not Tinned.
`Finished 0. D. given above is nominal. A tolerance of plus or minus 5 % is necessary on account of variations in process of manufacture.
I'i STOCK REEL LENGTHS:--Sizes No. 6 and larger, 500 Feet--Sizes No. 8 and smaller, 1000Feet.
i
!
! ROCKBESTOS PRODUCTS
CORPOR ATION
NEW HAVEN. CONNECTICUT
RBB 00416
RBB 00417
ROCKBESTOS -the asbestos covered, wire
SWITCHBOARD WIRES and CABLES
for wiring
Switchboards Elevator Control Panels Car Heating Circuits Power and Lighting Circuits
Resistance Grids Rheostats Traffic Signal Systems Electric Furnaces
i
S.Bt 10. 1020
RBB 00418
Rockbestos Switchboard Wires and Cables
""V
SWITCHBOARDS which are wired with rubber insulated or slow burning wires are, in the opinion of leading engineers, fire hazards that should be eliminated. The additional cost of ROCKBESTOS Switchboard Wire is the cheapest kind of fire insurance, it is guar anteed not to communicate fire even if it be subjected to contact with an electric arc.
MISCELLANEOUS other uses for ROCKBESTOS Switchboard Wires and Cables are listed on the cover of this bulletin.
SPECIFICATIONS covering construction and testing of our All Asbestos Insulated Wires and Cables are published in our Rockbestos Wires and Cables Bulletin. The construction, briefly, is as follows:
CONDUCTOR. Copper, bare or tinned, solid or stranded.
INSULATION. Is all asbestos, applied by the Rockbestos Felted process, providing ample dielectric and mechanical strength. Can be impregnated with white flameproof compound which can be used where no moisture is encountered, but we strongly recom mend black impregnation which is flameproof and moisture resistant. The compound in the insulation does not affect the color of the outside braid.
COVERING. A heavy asbestos braid approximately 45 mils in thickness finished with white or colored flameproof or black flameproof and moisture resistant compound.
These cables can be furnished with two or more conductors, under one cover, if desired.
Where additional dielectric strength or moisture resistant qualities are desired we can insert varnished cambric in the felted wall. For wall thicknesses, diameters and other information see following tables. Standard construction on sizes larger than No. 8 is a felted wall of asbestos next to the conductor, three layers of varnished cambric and another felted wall of asbestos and covered with a heavy asbestos braid. Sizes No. 8 and smaller, two layers of varnished cambric are applied next to the conductor and then a felted wall of asbestos and an asbestos braid.
For applications, requiring the smaller sizes, where there is danger of conducted heat which might damage the varnished cambric, we can furnish the construction with the felted wail of asbestos next to the conductor so as to insulate the varnished cambric against over heating.
On Switchboards installed in locations which would subject the wiring to high tempera tures we recommend the use of our ROCKBESTOS all asbestos switchboard wire. For con struction specifications see Table A.
On Switchboards installed in power generating plants, substations and other locations where appearance is of importance or for re-wiring or additions to existing boards that have been wired with varnished cambric insulated switchboard wire having a gray or black flame proof cotton braid we recommend the use of ROCKBESTOS varnished cambric asbestos insulated flameproof cotton braided switchboard wire. The construction of this wire is a tinned copper conductor insulated with two layers of varnished cambric, 30 mils of felted asbestos, saturated with a flameproof and moisture resisting compound, and covered with a gray or black flameproof cotton braid. The braid is closely woven and will not break or open on sharp right angle bends. It meets all the requirements as to dielectric strength, insulation resistance, appearance, uniform diameter and in addition gives the advantage of ROCKBESTOS insulation which will positively prevent the varnished cambric from igniting regardless of the amount of flame applied to it. It will continue to operate under conditions that would destroy any other type of switchboard wire. For construction specifications see Table B.
,3T manufacture asbestos insulated wires ana cables jor every purpose. Descriptive bulletins on request
RBB 00419
'****--
TABL3 A
See remarks- applying to Table I *SGCKBBSTOS
Vires and Cables" bulletin. This is the same mater
ial*
TABLE B
This material was designed: for the specifio purpose of wiring switchboards and panel boards*:
Before this wire was available- the customary practice was to use a "switchboard wire* made up with several layers (5 or 6) of varnished cambric
tape over which is placed, a tight cotton braid finish ed with a gray flameproof, paint* .The product of each manufacturer is approximately the same shade , of .color*
* The standard practice in wiring switchboards
is tc make sharp, square bends, the sharper-the bend: the,better the appearance of the completed board* But when a sharp bend is attempted in a wire with this multi-layer cambric construction, the cracking of the
braid on corners is a frequent occurrence. In making the bend the cotton braid has to atretoh around the corner. Something just has to give and if the-cambric layers beneath will not then the braid must stretch and sometimes cracks open entirely.
Now in ROCKBBSTOS switchboard wire this trouble
is done away with entirely by the use of a cushioning
wall of asbestos ***..
placed
j, ust
beneath
the
ce. tt. on
braid.
-When a sharp bend, is mads the cotton braid
pulls-down on this felted wall very tightly.-on the:
outside of the bend,, the felted wall in turn- compress
es or gives" slightly and a perfectly smooth bend is
the result*
: . ..
An important feature is that a .switchboard man ufacturer can save time in the-wiring of his product
RBB 00420
TABLE B continued
"because the wiremen do not have to be especially care ful in making bends not to crack them.
And to central stations a wire like this means always a fine appearance on the completed board something they are very proud of.
Along the line of fine appearance central station engineers have been interested in learning
that dust will not readily* collect on ROCKBBSTOS switchboard wire. This is accomplished by using a specially prepared (gassed) cotton yam. This pro
cess burns off the "whiskers9 which are what catch the dust.
Then of course there is the protection against fire hazard. A complete report entitled "Report of Tests covering the New Rockbestos Switch board Wire" is contained in the "test reports9 sec tion of this book. A part of this report is the ap proval report of the laboratory of the Associated Factory Mutual Fire Insurance Companies of Boston, Massachusetts
This is an independent laboratory maintain
ed by a group of industrial fire insurance companies for the sole purpose of passing on materials enter ing into the construction of properties they insure.
Safety is the only reason for their inter est in these materials.
Naturally they conduct some very severe tests. Note especially paragraph II on "Tests9 in their report. Consider what would have been the re sult had the usual multi-layer cambrio construction
switchboard wire been subjected to the same test.
Other uses:
.
Flameproof connections for transformer vaults.
RBB 00421
Rockbestos Switchboard Wire
All Asbestos Insulation --Asbestos Braid
Size A. W G. (B. &S.)
BARE
0000 Q00 00 0 1 2
3 4 5 6 8 10 12 14 16 18
Solid
Felted
Copeer AiOesioi
Conductor
Asbestos Braid
Table A
SOLID CONDUCTOR
Bare Dia.
Wall Thickness
Mils
aVi
t-4 33
-- 600 VOLT SERVICE
Asrs*-
Finished *
Pounds
per M ft.
Standard Shipping Length (Maximum in feet)
Coils
Reels
.460 .409 .365 .325 .289 .257 .229 .204 .182 .162 .128 .102 .081 .064 .051 .040
<
b0 g .b/0
60 .620
730 590
1500 1000
60 .575 480
1000
bO .535 390
1500
>5 35
V
.449 .418
300 245
2000 2500
35 35
.389
ctHac .364
35 3 .342
35 lb .322
35 O .289
200
165
135
no
75
2500 1000 1000 500 1000 500 1000
35 .262 55 500 1500
30 2 .231
40
1000
2000
30 o .214
30
1000
2500
25
.191
25
1000
3000
25
.180
20
1000
3000
Varnished Cambric and Asbestos Insulation--Flameproof Cotton Braid
Solid Copper Conductor Tinned
Varnished Cambric
Felted
Gray Flameproofed Cotton Braid
Asbestos
'
Table B
Size A. W. G. (B. Si S.) Tinned
Bare Dia.
SOLID CONDUCTOR -- 600 VOLT SERVICE
V. c.
Felted Wall Mila
Thick ness Braid Mils
Approx. O. D.
Finished *
Pounds per
Standard Shipping Length (Maximum in j
M ft.
Coils
Reels
8
.128
2-.005"
30
10
.102
2--.005'
30
N4
oo( *
12 .081
30
UOos
r-Ii
14 .064
30
20 .258 72 20 .232 51 20 .211 36 20 .194 27
500 500 1000 1000
1000 1500 2000 2500
Finished 0. D. given above is nominal. A tolerance of plus or minus 5% is necessary on account of variations in process of manufacture.
RBB 00422
Rockbestos Switchboard Wire
Asbestos Insulation with Varnished Cambric Insert
Asbestos Braid
This is the construction of No. 0000 to 6 inclusive.
This is the construction of No. 8 to 18 inclusive.
Table C
Size A.WG. (B. fitS.)
Bare
Bare Dia.
First Felted Wall
Mils
V. C.
SOLID CONDUCTOR
Second Felted Wall
Mila
Agpr.
Standard Shipping
{/}
sNa
(A
Pounds Length (Maximum in feet)
Finished *
Per M ft.
Coils
Reels
0000 .460 15 3- 005'
000 .409 15 3- 005'
0Q .365 15 3- 005'
0 .325 15 3- 005'
I .289 15 3-.005'
2 .257
15
3- 005*
3 .229 15 3--.005*
4 .204 15 3-005*
5 .182 15 3--.005'
6 .162 15 3--.005*
8 .128
2-.Q05'
10 .102
2-005*
12 .081
2-005'
14 .064
2-005*
16 .051
2-005'
18 .040
2--.005'
< 30 .680
30 O .629
30 30 *
.585 .545
30 Q .509
15
< ec
.447
15 a .419
15 3 .394
15
H D
.372
15 O .352
20 o .283 20 Cfl .257
20 Ui .236
20 .219
20 .206 20 h .195
740 600 485 395 322 255 210 175 145 115
75 55 40 30 25 20
500 500 500 1000 1000 1000 1000
1500 1000 1000 1500 1500 2000 2000 2500 1000 1000 1000 1500 2000 2500 3000 30Q0
*Finished 0. D. given above is nominal. A tolerance of plus or minus 5% is necessary on account of variations in process of manufacture.
RBB 00423
'W
TABLE C
The development of a moisture resisting asbes tos insulated wire was a natural step. In applying asbestos insulated wires to high temperature appli cations moisture would occasionally be encountered.
For instance, asbestos insulated wire for mo tor secondary circuits in conduit in a hot boilerroom would be ideal but the conduit may pass through the boiler-room wall to a much cooler area. This may cause condensation and if the conduit is placed so that bends or loops exist at the bottoms of vertical runs there is even the chance of water pockets form
ing temporarily. The Table A material with the felt ed wall impregnated with black moistureproof and flame proof compound will resist casual moisture but lying half submerged in a water pocket is a different matter.
All conduits should be cleaned at the comple tion of installation and should be provided with drain plugs at low points. If, however, the placing of con duits is such that there is doubt as to their continued dryness we would recommend Table C wire or, in extreme conditions, Table B cable.
Table C wire is generally used on electric ranges destined for certain export markets in order that the range, will meet certain insulation resistance require ments laid down by inspection rules in those markets,
CENTRAL STATIONS AND INDUSTRIAL PLANTS
Lighting circuits
Control
*
MISCELLANEOUS
Electric ranges for export Conduit wiring for industrial baking ovens Lighting and control circuits in areas where
gases or corrosive fumes are present, such as in chemical manufacturing plants.
Miscellaneous circuits in paper mills, around evaporators, etc.
TABLE D
Refer to remarks opposite Table II. This is same material.
RBB 00424
Rockbestos Switchboard Cables
All Asbestos Insulation Asbestos Braid
Iff*-!
Stranded Coor>er Conductor
Felted Asbestos
Asbestos Braid
Table D
STRANDED CONDUCTOR
Size
500.000 C. M. 450,000 C. M. 400,000 C. M. 350,000 C. M. 300,000 C. M. 250.000 C. M.
0000 B. & S. 000 00 0 l 2 3 4 5 6 8 10 12 14
Stranding Bare
Bare Dta.
Wall
Thicknett Mila
37/. 1102 37/.1103 37/.1039 37/,0973 37/.090 37/.0822 19/.1055 19/.0940 19/.0837 19/.0745 19/,0664
7/.0974 7/.0867 7/.0772 7/.0688 7/.0612 7/.0486 7/.0385 7/.0305 7/.0242
.815 .773 .729 .681 .630 .575 530 .470 .420 .374 .332 .295 .260 .234 .209 .185 .145 .116 .092 .073
120 120 120 120 120 120 90 90 90 90 90 90 60 60 60 60 35 35 30 30
-- 600 VOLT SERVICE
SIZES
Va'
Standard Shipping
Pounds Length (Maximum in ft.)
Finis*hed Tt
Coils
Reels
1.145 1775
< 1.103 1610
1.059 1450
g 1.011 1280 .960 1115
3 .905 950
.800 785 Q .740 640
ec .690 520
.644 430
ee lit
.602 350
h .565 290
O .470 225
& .444 185 .419 150
$ .395 125
2 .305 80
O .276 55
X .242 H .223
40 30
500 500 500 1000 1000
'
750 1000 1000 1000 1000 1000 1000 1500 1500 1500 1000 1000 1500 2000 2500 2500 1000 1000 2000 2000
Finished 0. D. given above is nominal. A tolerance of plus or minus 5% is necessary on account of variations in process of manufacture.
RBB 00425
r
Rockbestos Switchboard Cables
Asbestos Insulation ivith Varnished Cambric Insert
Asbestos Braid
Stranded Felted Varnished Felted Copper Asbestos Cambric Asbestos Conductor
Asbestos Braid
Table E
i
o % ALL S1ZI
||I
ic y
*
oo
1
STRANDED CONDUCTOR
Firat
Second
Approx.
dard
Strand*
Felted
Felted
0. D. Pounds
{Length
Size
Binar*e
Bare Wall Dia. Mils
V. c.
WaU Mils
CO
Fin per ished M ft.
m in ft.)
m Coils Reels
500,000 C. M. 37/.1162 450,000 C. M. 37/.1103 400,000 C. M. 37/.1039 350,000 C. M. 37/.0973
300,000 C. M. 37/.090 250,000 C. M. 37/.0822
0000 B. & S. 19/.1055
000 19/. 0940 00 19/.0837
0 19/.0745 1 I9/.0664 2 7/.0974 3 7/.0867 4 7/.0772 5 ' 7/.0688 6 7/.0612 8 7/.0486 10 7/.Q385 12 7/.0305 14 7 '.0242
.815 .773 .729 .681 .630 .575 .530 .470 .420 .374 .332 .295 .260 .234 .209 .185 .145 .116 .092 .073
30 3-005' 30 3-.005' 30 3--.005' 30 30 3- 005' 30 3-005' 15 3-.005' 15 3-.005' 15 15 3-.005' 15 3-.005' 15 3--.005' 15 3-.005' 15 3--.005' 15 3--. 005' 15
15 3- 005' 15 3-.005' 15 3-.005' 15 3--.005"
oo1
N/l %
45 45 45 45 45 45 30 30 30 30 30 15 15 15 15 15 15 15 15 15
1.095 1743
1.053 1580
O 1.009 1417
.961 1253
.910 1088
.855 922 a .750 76!
.690 616 SB .640 500
.594 410 H .552 335
0 .485 265
.450 216
0 .424 180
CO .399 149
m z
.375
120
5Q0
.335
85 500
I .306 62 500
H .282
47 1000
.263 37 1000
750 750 1000 1000 1000 1000 1000 1500 1500 1500 1000 1000 1000 2000 2500 2500 2500 1000 1000 1000
^Finished 0. D. given above is nominal. A tolerance of plus or minus 5% is necessary on account of variations in process of manufacture.
BBB 00426
TABL3 3
This material is generally used where con ditions prevail similar to those described in Table C.
A good many firms which would probably find Table C material satisfactory make doubly sure of: obtaining continous service by standardising on Table B cable. Ford Motor Company is one of these using it for motor leads.
It will be seen by a comparison of the two tables that the smaller sizes of Table C are insulated with two tapes and a felted wall, whereas the corres ponding sizes in Table B construction have two walls and three tapes between.
The larger sizes (from #1 B&S up) have heavier top walls of felted asbestos and cable of this construc tion provides the utmost protection against conditions of heat, heat and moisture, abrasive dusts such as coal dust, mineral dusts, etc., oils, gases, and so on.
Where the basic condition of service is heat and any or all these other conditions are involved this is the material to recommend.
Ashpit wiring gives as severe a test to wire in conduit as any application we know of. Hot ashes drawn from furnaces are dumped in the pits and water sprayed on them for rapid cooling. This causes extreme conden sation in conduits near the pit, therefore ashpit cir cuit failures are common and expected. To correct this condition Table 3 material has been used with suc cess and should always be recommended for this applica tion. Some companies go so far as to specify a lead sheath- over this cable.
An interesting point in selling this expensive cable is that the first cost is of no particular im portance if the cable will do away with expensive re placement labor. Users* experience has shown that this i3 exactly what it does and that it becomes practically a permanent Installation.
This type of cable is made for service voltages up to 7500 by increasing the number of cambric tapes
RBB 00427
TABLE E continued
. between the felted walls.
is:..
The number of tapes for the various services
Service
Ho. of Tapes
600 volts 1500 "
3500 " 5000. 7500 0
3 6
9 12 18
The applications for this type of cable are gen erally the same as those shown for Table C material, the construction being approximately the same except for the stranded conductor and different thickness of the insulated walls in the larger sizes.
Uses:
All conduit applications
Motor Leads Lighting and control circuit
ashpit wiring.
CAUTION
Customers using any asbestos and varnished cambrio insulated cable in oonduit should be cautioned about-the- kind of lubricating compound they use. A neutral> lubricating grease should be used.
There are a number of brands of lubricating
grease on the market in the country which are strong
ly alkaline. These greases are soluble in water and
when condensation takes place in conduit it is possi
ble for this grease to penetrate to the cambric and
eat the varnish away.
The grease, however,, has no effect on rubber in sulation.
RBB 00428
Where and how Rockbestos
Switchboard wires and cables are being used
CONTROLLER FOR OIL WELL MOTOR
FIELD RHEOSTAT
ELECTRIC FURNACE
CENTRAL STATION SWITCHBOARD
RBB 00429
RBB 00430
ROCKBESTOS -the asbestos covered, wire
ROCKBESTOS Wires and Cables
Designed especially for wiring lighting circuits and all low voltage auxiliaries in Central Stations and
Industrial Plants, Electric Railway motor, Transformer and Shoe leads.
SM. 10. 1929
RBB 00431
Rockbestos Wires and Cables
V^/ONTINUITY of service is of paramount importance in power plant operation, electric railway service and manufacturing establishments. Rock bestos cable is the result of many years of experimental and research work to develop cables that would insure this continuity of service under the most severe conditions, especially where heat is encountered or where communica tion of fire thru insulated conductors would prove disastrous.
Rockbestos cable is rapidly being accepted as the standard for all lighting and low voltage power and control circuits in power plants. Boiler room wiring has been a constant source of trouble that has been eliminated by the use of Rockbestos cables. Our type of cable has been operating successfully installed in conduit, in power plants, electric locomotives and steel mills for a number of years, where other types of insulated cables have failed within a comparatively short time.
This specification contains all of the necessary engineering information to enable you to choose the cable best adapted to your particular requirements. Where added dielectric strength and greater moisture resistant properties are wanted, we recommend our A. V. C. type cables which are described in a sepa rate bulletin.
General Characteristics
Asbestos insulation applied by the "Rockbestos Process" will not deteriorate electrically or mechanically with age or under severe heat conditions. It will not carry flame even if it be subjected to contact with an electric arc. It will operate continuously without deterioration at any temperature up to 400 F. and will retain a large part of its electrical and mechanical strength up to the fusing point of the conductor.
Permanently flexible as consistent with the stranding of the conductor. Rockbestos insulation will withstand casual moisture and will operate satisfactorily in conduit under proper conditions of installation. The outer finish will withstand abrasion incident to installing in iron conduit. Rockbestos insulation is unaffected by the fumes of most acids. A few typical applications and installations are shown in the photographs on the last page.
V'e manufacture asbestos insulated wires and cables for every purpose. Descriptive bulletins on request
3
3
rBB 00432
Standard Specification
for ROCKBESTOS
Asbestos Insulated Wires and Cables
General: This specification provides a standard for materials, workmanship, and
testing of asbestos insulated wires and cables for applications where freedom from communication of fire or deterioration by severe heat conditions is of primary importance, such as lighting circuits, switchboard wiring, primary and secondary motor leads, control circuits, rheostat wiring, resistance grids, low voltage power feeders and similar installations.
1. Copper: Bare or tinned copper shall conform to A.S.T.M. standards.
2. Insulation: The asbestos shall be pure, long fibre material, commercially free from
metallic oxides. It shall be applied in the form of untwisted rovings compressed and impregnated with a neutral heat and moisture resisting compound to pro duce a continuous, uniform felted layer of thickness specified. (See Tables I, II, III, IV, V.)
The insulation shall be applied so as to provide a circular cross-section in which the conductor is well centered in the insulating wall.
The impregnating compound shall be black except where extreme heat and no moisture conditions are present, in which case white compound should be used.
3. Braid: 600 Volt Service. A closely woven braid approximately .045 thick of asbestos yam shall be
applied over the felted insulation. 1500 Volt Service. An asbestos braid shall be incorporated approximately in the center of the
felted wall, for the purpose of increasing the mechanical strength of the in sulation.
Over the finished insulating wall a closely woven braid of 20/2 cotton shall be applied to form a tough outer covering that will resist wear and serve to protect the felted asbestos during installation.
rBB 00433
4. Finish:
The outer braid shall be saturated with a flameproof and moisture resisting compound. The color shall be black except where extreme heat and no moisture are encountered or where white is desirable for appearance. Other colors can be furnished for purpose of identification.
The compound used shall consist of suitable high grade ingredients and shall retain its initial qualities during the life of the cable. The compound shall develop no injurious chemical action within itself or with any other of the component parts of the completed cable. It shall be of such a character that it will not drip from the completed cable at any temperature up to 500 C.
5. Tests:
() Dielectric.
Tests for dielectric strength of insulation shall be made between conductor and metal foil wrapped over insulation for a length of about 5 feet. The test voltage applied shall be two and one-half times the rated working potential of the wire under test and shall be held for one minute without failure.
A section of material having black impregnated insulation shall be im mersed in water (except ends) for one hour and shall then withstand a test volt age of two times the rated working potential of the wire under test, applied between conductor and water, for one minute without breakdown. White impregnated insulation shall not be subjected to water test.
() BerxdingTest:
A new section of finished cable shall be bent 360 around a mandrel 8 times the diameter of the finished cable, then straightened and bent 360 in the op posite direction around the same mandrel, after which it shall be straightened and the section which was bent wrapped with metal foil. A test voltage equal to that shown in Paragraph 5 shall then be held for one minute between conductor and foil without failure.
(c) Flame Test:
The wire (after seasoning) must not convey fire nor support combustion for more than one minute after five fifteen-seconds application of a standard test flame -- the period between applications of test flame being 15 seconds.
The flame used is a blue flame (about 5 inches in height) obtained with a /l 2 inch Bunsen burner fed with ordinary illuminating gas at normal pressure. Previous to the test the burner and the gas supply lines are adjusted to give a flame of the character described above.
The sample is about 18 inches long and is rigidly suspended vertically, by means of a clamp attached to a ring stand, in a room from which all drafts of air are excluded.
3>
0
RBB 00434
The hot part of the ''tip" of the test flame (i. e. the part over the blue cone in the flame) is applied nearly parallel to the suspended sample at a point about 3 or 4 inches above its lower end. The flame is applied to the sample for 15 sec onds and then removed and after a 15 second interval (whether the flaming on the sample has ceased or not) the test flame is again applied at the same portion of the sample for 15 seconds and removed and the above operations repeated until the test flame has been applied at the same portion of the sample for five times.
During the test, as well as after the fifth application of the test flame, observation is made to determine whether or not the area of the sample sup porting the flaming extends outside the area exposed to the heat of the test flame (the effect of the heat of the test flame is considered as extending an inch or so beyond the "tip" of the test flame.) Behavior and duration of flaming on the sample after the fifth application of the test flame are also noted.
After the cable has cooled for five minutes the section to which the flame was applied shall be bent as in 5-b, straightened and wrapped with metal foil. The insulation shall then withstand for one minute the test voltages given in Paragraph 5 applied between conductor and foil. 6. Inspection:
Testing and inspection shall be made at the place of manufacture unless otherwise noted on purchaser's order. The manufacturer shall afford the in spector representing the purchaser all reasonable facilities to enable him to satisfy himself tha.t the material conforms to the requirements of these specifications.
RBB 00435
Construction Specifications
Rockbestos 600 Volt Solid Conductor
Size A. W. G. (B. & S.)
BARE
0000 000 00 0 l 2 3 4 5 6 8 10 12 14
Solid
Felted
Cooper Asbestos
Conductor
Asbestos Braid
Table I
SOLID CONDUCTOR
Bare
.460 .409 .365 .325 .289 .25 7 .229 .204 .182 .162 .128 .102 .081 .064
Wall Thickness
Mils
60 60 60 60 35 35 35 35 35 35 35 35 30 30
V) a
g <
9
X
O
a
<
03
(eU H 3 O
O Crt
<A
z
x
U
5
-- 600 VOLT INSULATION
O. D.
1
Pounds 1 Standard Shipping per Length (Maximuminfeet.)
Coils
Reels
.670
730
1500
620 590
1000
.575
480
1000
.535 390
1500
.449
300
2000
.418
245
2500
.389
200
2500
.364
165
1000
.342
135
.322 no
1000 500 1000
.289 75 500 1000
.262 55 500 1500
.231
40
1000
2000
.214
30
1000
2500
Finished 0. D. given above is nominal. A tolerance of plus or minus 5% is necessary on account of variations in process of manufacture.
tm
0
RBB 00436
TABLET
This wire, has th& greatest' number of Uses
of any wire in the line. rt has a. large sale* to in
dustrial plants and central stations for maintenance
and permanent installations! to* manufacturers for in
clusion in their products, and to many other classes*
of users for various applications involving higji tem
peratures.
.
While this all' asbestos insulated wire has been sold for many conduit installations, the general
recommendation should be the combination varnished cambric and asbestos insulation shown in tables C. and.
a.
If the service conditions^ surrounding sin
application are continuously applied high temperatures,
an all asbestos insulated wire would be suitable.
But if there is a possibility of slight moidtufe due to
condensation or other causes the Table C type of mate
rial should be used. If considerable moisture is likely
to be encountered, the Table material should be invar
iably recommended.
' ''
CENTRAL STATIONS AND INDUSTRIAL PLANTS
Boiler Room Lighting,. Circuits
Ceiling or flood lights Wall bracket flights.
Water column 'lights . /
Boiler-Room- Control Circuits, . .
Auxiliary equipment, such &a*. . ...........
Oil circuit breakers to control panel"
Indicating lamp, leads to control panel
Current transfbrnier leads** tb oohtrol
.. .
panel- -
.-
Boiler control to .boiler control panel
Damper control drive to control panel
Limit switch connection's for oontraotors
to motors* etc*. - . .
Start and stop push* button connections
to contractors-* eto.T~- - - .
RBB 00437
TABL5 I continued
Rheostat Wiring and Connections
Switchboard Wiring, (back of panel) where
fire hazard exists
'
IRON AND STEEL INDUSTRY ' .
Rheostat Wiring
Lighting Circuits Crane cab resistor wiring Wiring around soaking pits
" * electric furnaces
-
MISCELLANEOUS
Electric Ranges and Hot Elates (see "Range Wire* bulletin)
Elevator control panels etc.
Table II
This is generally used for much the same appli cation as Table I material where large size or indiv idual preference requires a stranded conductor.
The second and third paragraphs under Table I on the preceeding page explain when it is desir able to make the alternate recommendation of varn ished cambric and asbestos Insulated cable which al so applies to this stranded construction,
BOILER ROOMS
Frioary Rotor Leads
Induced and forced draft fan motors Rotor operated steam valves Electric hoist motors
Aro Welding Power Leads'
IRON AND STEEL INDUSTRY
Rotor Leads to Rotors Operating Furnace Doors
RBB 00438
Construction Specifications
Rockbestos 600 Volt Stranded Conductor
Size
Stranded Copper Conductor
Felted Asbestos
Asbestos Braid
Table II
STRANDED CONDUCTOR
Stranding Bare bare Diam.
Wall Thick-
nesa Mils
-- 600 VOLT SERVICE
O. D. Fin ished
Standard Shipping Pound* Lengths (Maximum in ft.)
Coils
Reels
1,000.000 CM. 900,000 800,000 750,000 700,000 600,000 500,000 450,000 400,000 350,000 300.000 250.000
A.W.G. 0000 000 00 0 i 2 3 4 5
6
8
iO
12
14
61/.1280 61/.1215 61/.1145 61/.1109 61/.1071 61/.0992 37/. 1162 37/.1103 37/.1039 37/.0973 37/.090 37/.0822
19/.1055 19/.0940 19/.0837 19/.0745 19/.0664 7/.0974 7/.0867 7/.0772 7/.0688 7/.0612 7/.0486 7/.0385 7/0305 7/.0242
1.152 1.093 1.031 .998 .964 .892 .815 .773 .729 .681 .630 .575
.530 .470 .420 .374 .332 .295 .260 .234 .209 .185 .145 .116 092 .073
120 120 120 120 120 120 120 120 120 120 120 120
90 90 90 90 90 90 60 60 60 60 35 35 30 30
v> 1.482 3400
N 1.423 3075 Vi 1.361 2750 J 1.328 2590
< 1.294 2425
as 1.222 2105 1.145 1775
1.103 1610
1.059 1450
Q LOU 1280 < .960 1115 a .905 950
OO
ous .800
3 .740 640
O
.690
520
( .644 430
.602
350
</) .565 290
z .470 225
s
.444
185
X
.419
150
.395 125
500
.305 80
500
.276
55 . 500
.242 40
1000
.223 30
1000
500 500 600 600 750 750 750 1000 1000 1000 1000 1000
1000 1500 1500 1500 1000 1000 1500 2000 2500 2500 1000 1000 2000 2000
Finished 0. D. given above is nominal. A tolerance of plus or minus 5% is necessary on account of variations in process of manufacture.
RBB 00439
Construction Specifications
Rockbestos 1500 Volt Stranded Conductor
Size
Stranded Copper Conductor
Felted Aabenoe
Asbesto* Braid
Felted Asbestos
Table III
Flameproof Cotton Braid
STRANDED CONDUCTOR
Stranding Bare BARE Diam.
Wall Thick-
new
Mila
-- 1500 VOLT SERVICE
O. D.
Fin ished
Standard Shipping Pounds Lengths (Maximum in ft-)
per M ft.
Coils i Reels
1,000.000 CM. 900,000 800.000 750,000 700,000 600.000 500,000 450,000 400,000 350,000 300,000 250.000 A.W.G. 0000 000 00 0 1 2
3 4 5 6 8 10 12 14
61/.1280 61/.1215 61/.1145 61/.1109 61/.1071 61/.0992 37/. 1162 37/. 1103 37/.1039 37/.0973 37/.090 37/.0822
19/. 105 5 19/.0940 19/.0837 19/.0745 19/.0664 7/.0974 7/.0867 71.0771 7/.0688 7/.0612 7/.0486 7/0385 7/.0305 7/.0242
1.152 1 093 1.031
.998 .964 .892 .815 .773 .729 .681 .630 .57 5
.530 .470 .420 .374 .332 .295 .260 .234 .209 .185 .145 .116 .092 .073
.187 .187 .187 .187 .187 .187 .187 .187 .187 .187 .187 .187
.187 .187 .187 .187 .187 .187 .157 .157 .157 .157 .157 .157 .157 .157
1.586 3500 1.527 3175 V) 1.465 2840 J 1.432 2680 1.398 2515
2 1.326 2185 2 1.249 1850
1.207 1685
9 1.163 1515
1.115 1350
< 1.064 1180 a 1.009 1010
ta .964 875
.904 725
.854 600
ii, 0
.808
505
.766 425
(A .729 360
.634 280
o .608 240 X .583 205
.559
180
.519
135
.490
110
.466
90
.447
80
400 400 500 500 500 600 750 750 750 750 1000 1000
1000 1000 1000 1000 1000 1500 1500 1000 1000 1000 1500 1500 1500 2000
Finished O. D. given above is nominai. A tolerance of plus or minus 5% is necessary on account of variations in process of manufacture.
RBB 00440
TABLE III See Table V for remarks which apply here as well. This is the same material with a coarse stranded conductor.
RBB 00441
..J
TABLE XV-
Certain variations of the applications men tioned under Table I and II require a flexible strand ed conductor. Motor leads on large motors are an ex ample. By motor leads in this case is meant the leads extending from the coils inside the frame, out through bushings for a short distance ready for connections to line wires.
Asbestos insulated motor lead cables may be
used on a motor for several reasons. They should be
used if the location of the motor is in a high tem
perature area in order that there shall be no deteri
oration of the leads as would be the case if rubber in
sulated leads were used. Steel mill motors, motors on
auxiliary equipment in boiler rooms, etc. come in under
this classification.
-
The above treats on the desirability of using an asbestos insulated as against a rubber insulated motor lead. In general the recommendation for motor leads for all applications would be a lead insulated with a combina tion of varnished cambric and asbestos. This is shown in the "A.V.C. Cables" bulletin and in Table E of the "Switchboard Wires and Cables" bulletin.
A large motor may be engaged in such duty that it is heavily overloaded at intermittent periods. An
elevator motor, for instance, or a mill motor on process work, draws a tremendous overload current at the start
of its operation. This sometimes causes conductor heat ing. Continued recurrence of this heating vulcanizes rubber insulation so that it becomes brittle and cracks. To guard against this' development an asbestos insulated cable should be used because this heating has no effect whatever on it and the insulation stays permanently flex ible which is a distinct advantage.
. . Many central stations and industrial plants have used' thousands of feet of similiar materal for motor lead application as they realize that it provides a permanent installation'.
. Insulated cable of this construction is used on subway, cars. Where the cable attaches! to- a connection
RBB 00442
--cm
TABLS-IV continued
point a lug is used, sweated to the cable and bolt ed to the connection.
The constant motion and vibration -of cars frequently loosens the cable from the lugs. Some times a high resistance joint is .set up, overheat ing takes place and arcing begins. An asbestos in sulation will successfully confine fire to the point
of origin so that adjacent inflammable material will not be set afire.
It is a common experience for a cable to
break under load perhaps at the lug- An arc forms
immediately and continues until the cable falls away
or until the copper melts and increases the gap thus
stopping the arc.
`
To be warranted in using asbestos insulated motor lead cables for these cars the traction compan
ies must be assured that they will not transmit flame or fire and that they really will not bum themselves*.
An interesting report entitled "Arc Flame Tests on Motor Lead Gables" is contained in the "test reports" section of this book and clearly shows the performance of asbestos insulated cable as com pared with the rubber insulated type of cable.
.
Other uses;
Inside motor connections Arc welding power leads Headlight wiring where the train, control system is not used*- *
----- * Where the train control system is installed, it is customary to feed all circuits from one genera
tor. For this reason every circuit on the locomotive should be wired with the same- kind of insulated wire
so that the dielectric strength of all parts of the wiring system will be the same. (See last paragraph under the page entitled Cab Cord*)
* Our recommendation for train control system wiring is the varnished cambric and asbestos insula tion shown in the "A.V.C, Cable" bulletin or Table B of the "Switchboard Wires and Cables" bulletin.
RBB 00443
Construction Specifications
Rockbestos 600 Volt Flexible Conductor
Flexible Tinned
Copper Conductor
Felted Aabeeto*
Atbesto* Braid
Table IV
FLEXIBLE STRANDING
Size
Stranding
Tinned
Bare Diam-
Wall Thick
ness Mil*
500,000 C.M. 427-->1x7(0338)
450,000
427-61x7(0319)
400,000
427-61x7( 030;)
350,000
427-61x7( 0284)
300,000
427-6Ix7(.0269)
250,000
259-37x7(.0320)
A.W.G,
0000
259-37x7(.0284)
000 259-37x7( 0253)
00 259-37x7( 0226)
0 259-37x7(0201)
1 133-19x7(0253)
2 133--19x7(.0226)
3 133-I9x7(.0201)
4 133-19x7( 0179)
5 49- 7x7( 0253)
6 49- 7x7(.0226)
8 49- 7x7( 0179)
10 37/ 01689
12 37/.01339
14 37/0106
.914 .863 .814 .768 725 .671
.598 .532 .474 .422 .380 .339 .302 .269 .228 .203 .161 .118 .094 .074
1M
120 120 120 120 120
90 90 90 90 90 90 60 60 60 60 35 35 30 30
-- 600 VOLT SERVICE
Standard Shipping
0. D. Pounds Length (Maximum in ft.)
Fin-
VUN3 ished M ft.
Coils
Reels
<75
1.244 1850 < 1.193 1655
ec 1.144. 1500 1.098 1350
1.055 1215
3 l.QOl 1060
750 750 750 1000 1000 1000
< .868 830
A2 .802 675
.744
550
tc VI
.692 460
5
.650
380
O
.609
310
s
.512
240
.479
200
%U1 .438 160
.413 130
.321 85
X .278
60
.244 41
.224
32
500 500 500 1000 1000
1000 1000 1500 1500 1500 1000 1500 1500 2000 2500 1000 1000 2000 2000
Finished O. D. given above is nominal. A tolerance of plus or minus 5% is necessary on account of variations in process of manufacture.
RBB 00444
Construction Specifications
Rockbestos 1500 Volt Flexible Conductor
Flexible Tinned Copper Conductor
Felted Asbestos
Asbestos Braid
Felted Asbestos
Table V
Flameproof Couoa Braid
Size
FLEXIBLE STRANDING
Stranding Tinned
Bare Diam.
Wall Thick
ness Mils
500.000C.M. 427-61x7(.0338)
450,000
427--61x7(.0319)
400.000
427-6lx7(.0301)
350.000
427-61x7(.0284)
300,000
427-61x7(.0269)
250.000
259-37x700320)
A.W.G.
0000
259-37x700284)
000 259-37x700253)
00 259-37x700226)
0 259-37x700201)
1 133--19x7 (.0253) 2 133-19x700226)
3 133-19x700201)
4 133-19x7( 0179)
5 49- 7x7(.0253)
6 49- 7x7(.0226)
8 49- 7x7(.0179)
10 37/.01689
12 37/.01339
14 37/0106
.914 863 .814 .768 .725 .671
.598 .532 .474 .422 .380 .339 .302 .269 .228 .203 .161 .118 .094 .074
187 187 187 187 187 187
187 187 187 187 187 187 157 157 157 157 157 157 157 157
--
eUfti 35 _i < a ou.
q
AS
s
as
u H O L&.
v)
z
*
u
2
1500 VOLT SERVICE
O. D.
Finished
Standard Shipping
Pounds Length (Maximum in ft.)
per
M ft.
Coils
Reels
.
1.348 1930 1.297 1735 1.248 ' 1575 1.202 1425 1.159 1285 1.105 1125
i 600
j 750 750 750 750 1000
1.032 .966 908 .856 .814 773 .676 .643 .602 .577 .535 .492 .468 .448
925 765 630 540 455 390 300 255 210 185 140 no
90 80
1000 1000 1000 1000 1 1000
1000 1500 1500 1000 1000 1500 1500 1500 2000
Finished 0. D. given above is nominal. A tolerance of plus or minus 5% is necessary on account of variations in process of manufacture.
N.S
RBB 00445
TAELB V
This is a special 1500 volt service asbestos
insulated cable designed for electric locomotive ap
plication. In such an application it is constantly
subject to abrasion so it is equipped with a tough
cotton braid which is finished with flameproof com-)
pound,
This construction of Insulation, however, is being superseded by that shown in Table B, Switch board Wires and Cables bulletin, which is now made for service up to 7500 volts by using from 3 to 18 layers of cambric tape, sandwiched between the walls of felted asbestos.
Where and how Rockbestos
wires and cables are being used
CONTROL BOARD CENTRAL STATION
STEEL MILL
ELECTRIC LOCOMOTIVE
BOILER ROOM
ELEVATOR CONTROLLER
RESISTANCE GRID
FIELD RHEOSTAT
HEAVY DUTY RESISTOR
RBB 00447
,>r. ?
F1TT9*U*aK`
ROCKBESTOS PRODUCTS
C'0OIATI0M MANU'ACTUMCMS O'
ASBeSTOS COVERED WIRES AMO CABLES
Xieou AMO CAMHCR JTMCtTl MEW HAVEN. CONN.
CMI6A0---
ROCKBESTOS INDUSTRIAL WIRES AND CABLES
There are certain quite well established pre
judices existing against any kind of a wire covered or insulated only with asbestos. Probably the major part
of this prejudice was caused by the discouraging exper iences of engineers with the earlier types of asbestos covered wire typified by "double braid asbestos cover ed" wire. This statement applies more particularly to wires and cables used for industrial and central sta tion applications. Wires of this variety could be used
in conduit but the slightest bit of moisture in the conduit caused grounds resulting in failure.
The insulation value of this type of asbestos covering is principally the space factor. There is no resistance to moisture because the braid is open and because the individual yams cannot be Impregnated.
For this reason we have stressed the fact in our advertising, sales literature, direct mail and sales letters that our material is "asbestos insulated" as opposed to "covered" although the word "covered" still remains^;* part: o our original slogan.
hygroscopic characteristic of asbestos
rs but the ad
vane ,, t have been made during the past few years in
the production of wires and cables insulated with as
bestos and so impregnated as to resist moisture are
not generally known. ROCKBESTOS trade paper advertis
ing, direct mail and general sales work aims to acquaint
engineers the country over with these advances as they
are represented in ROCKBESTOS wire products.
^
RBB 00449
2- -
BULLETINS
Following this section is a complete set of bulletins. Our experience has taught us that individual bulletins are much more efficient and less confusing in furnishing information.
. This is particularly true with our business be cause in many industries only one wire of our line can be used. Consequently when answering inquiries from such a field of prospects a single bulletin is sent which fully covers the case but which does not contain irrelevant in formation to detract attention from the main question.
It will be noticed that there are some duplica tions between bulletins. The previous paragraph explains this. An illustration is Table I in the "Switchboard Wires and Cables" bulletin and the first table in the "Range Wires" bulletin both of which show the same wire. The first named bulletin is generally sent to fuel burn ing central generating stations and the Table I wire has a large number of uses in such a place; boiler room light ing and control circuits, rheostat wiring, primary and secondary motor lead wiring and so on. A full range of sizes is shown in Table I.
The "Range Wire" bulletin shows the same thing but i&the restricted range of sizes generally used by electrift'range manufacturers. All the information that is needed by these manufacturers is shown and none that is not.
USES OF ASBESTOS INSULATED WIRES AND CABLES
Opposite each table and illustration is a fly page listing a variety of uses for that particular type of material,
RBB 00450