EEMAC
STANDARDS
FOR
WET—PROCESS PORCELAIN INSULATORS
t~POOLTYPE)
L
CEMA STANDARDS
for
WET-PROCESS PORCELAIN INSULATORS
(Spool Type)
1. Scope
11 These standards cover spool.type insulators
made of wet-process porcelain used in the tratismission and distribution of electrical energy.
2. Definitions
2.1 See Section 2 of the American Standard Insulator Tests,’ Publication No~ C29d.1944. or
latest revision thereof, for definition of terms.
Co~ies are available from the Americ*n Standards A~aoriation,
Inc.. 70 Eavt 45th Street, New York 17, N. V.
7. Packing
7.1 Jnsula~ors shall be so packed as to prevent
injury to them during transportation and handling.
Insulators paeked in containers conforming to all
construction requirements of Canadian Freight
classificatioz: as to bursting tests, sIze i~mitand
gross weight shall be considered as being adequately
packed.
7.2 Each box or container shall be marked with
the number of pieces contained therein, the catalogue number, or drawing number, or description
of the contents, and the manufacturer’s name.
3. General
31 Standard insulators shall conform in all respects to the requirements hereinafter stated. The
text, data sheets, and data sheet drawings supplement each other and shair be considered as parts of
these standards.
3.2 The data sheet drawings are type drawings,
and overall dimensions are shown.
3.3 Manufacturer’s drawings, if furnished, shall
show the outline of the insulators together with all
pertinent dimensions. Any variations in these di.
mensions due to manufacturing tolerances shall be
indicated.
8. Manufacturer’s Production
Sampling and Tests
8.1 The manufacturer shall make adequate tests
to determine that insulators manufactured in accordance with these standards will meet the requirements thereof,
9. Sampling, Inspection and Tests
9.1 General. Substantial test experience, over a
long period of tune, indicates that a total of % of
one per cent ol the number of insulators in a lot is
sufficient to establish characteristics demonstrable
by destructive tests.
4. Material
4.1 The insulators shall be made of good commercial grade wet-process porcelain.
4.2 The entire surface of the insulator, with the
exception of a firing surface, shall be glazed. The
standard color of the glaze shall be brown. The
entire surface shall be relatively free from imperfections.
5. Dimensions and Characteristics
5.1 Dimensions and characteristics shall be in
accordance. with the data sheets.
6. Marking
6.1 Each insulator shall bear a symbol identifying the manufacturer. The marking shall be legible
and durable.
January 2, 1957
9.2 Dimensions. Three insulators shall he selected at random from the lot and their dimensions
checked against the dimensions on the manufacturer’s drawing. Failure of more than one of these
insulators to conform, within manufacturing tolerances, to the dimensions on this drawing shall constitute failure of the I~tto meet this standard.
9.3 Design Tests. Certified test data on insula.
tors of existing design shall be regarded as equivalent to actual design tests. Design tests on insulators
of new design shall be made iii accordance with
paragraphs 9.3.1 and 9.3,2.
9.3.1 Low-frequency Dry.flaahover. Three
insulators shall he selected at random and tested in
accordance with Section 4.1 of the American Stand.
ard Insulator Tests, Publication No. C29.1.1944, or
latest revision thereof. Failure of the average dryfiashover value of the three insulators to equal er
1
tt~f~7
exceed 95 per cent of the rated dry-fiasho~rervalue,
as given on the applicable data sheet, shall constitute
failure to meet this standard.
lot.. Failure of more than 10 insulators total from
both the tirst and second samples shall constitute
failure of the lot to meet this standard.
9.3.2 Low./requency Wet-/lashover. Three
insulators shall be selectcd at random and tested in
accordance with Section 4.2 of the American Standard Insulator Tests, Publication No. C29.l-1944, or
latest revision thereof. Failure of the average wet.
flashover value of the three insulators to equal or
exceed 90 per cent of the rated wet-flashover value,
as given on the applicable data sheet, shall constitute failure to meet this standard.
9.4.2 Porosity. Test specimens shall be selected from insulators destroyed in other tests and
tested in accordance with Section 5.4 of the American Standard In.sula~or Tests, Publication No.
C29.1-1944, or latest revision thereof. Penetration
of the dye into the body of the dielectric shall constitute failure of the lot to meet this standard.
9.4 QualIty Control Tests
9.4.1 Visual. If vsual inspection is required
on Iota of 500 or more insulators, 50 insulators shall
be selected at random from the lot. If more than 4
but less than 10 of the insulators fail to meet the
requirements of paragraph 4.2, 100 additional insulators shall be selected at random from the same
January 2, 1957
9.4.3 Transverse Strength. Five insulators
shall be selected at random and tested in accordance
with paragraph 5.1.6 of the American Standard
Insulator Tests, Publication No. C29.1-1944, or
latest revision thereof. Failure of the average
strength of the five insulators to meet the strength
requirements given on the applicable data sheet or
failure of any one insulator to equal 85 per cent of
that strength requirement shall constitute failure of
the lot to meet this standard.
.
.
I
.
DATA SHEET
Class 53-1’
Class 53-2t
(~
~. th. f.)t.’.ia*
pseun-aph Iv. A~n.ive.*
kit.,.
Ch.iraetee~slies
1. MECWucAi. VALUES
a. Transverse Strength, Pounds
2.
5vsv.4.n~ S,...I.f.r
Chv.. 53-I
CI.~$3.2
Ci... $3-S
2000
3000
4000
5.1.6
20
25
25
4.1
8
10
12
15
12
15
4.2
Ti-si.,
P.S., k.. C29.l-184h
ELECTRICAL V.u..uES
a. Low-frequency Dry Flashover, Ky
b. Low.frequency Wet Flashover, Ky
1. Vertical
2. Horizontal
‘Side wire groove must seat not less than 13~-inehdiameter mandrel
IS’de wire groove must seat not leu than l~ -i~cbdiameter mandrel.
0
NOTE I—Tolerances
a=~veinch
d.~ inch
b=~ inch
c=3%~inch
c=t4c inch
f=%4 tnch
The use o( * single letter indicates the unse plus or minus tolcrancc, tor example. amplu. or minus
the minus tolerance. tor example, amnplus ~ Inch, taints. 0 inch.
gn% inch
h=½inch
j% inch
4.2
k1 inch
x0 inch
inch. Where two lettei, are used, the 6,me indicates th~plus soleranc. md the second Indicates
1~-~
2B-1,
1957
DATA SHE~ET
3 ~a
/
Clau 53—7
S
CI4ARA
1
9
I.
TERIS TICS
Class 53—5
Class 53—7
\
REFER TO ThE FOLLOWIHI
PARAIRAPN IN AME*~C.*N’
STANDARD RSIM.ATO~TESTS,
PU5,NO.C25.l.I044
ECP-tA?~GALVALUES
IRA
SV(RSE STRENGTH, POUNDS
4500
5500
30
40
4-I
15
20
28
4-2
4-2
5.1.6
2.~ F’~TRICALVALUES
,.OW-FREQUENCY DRY FLASHOVER~XV.
i. LOWFREQU~NCY *ETFLASP4OV~R,XV’
I. VERTIc~AL
i-s ORIZ ON TAt.
18
2
*~r:E NINE GROOVE MUST SEAT NOT LESS THAN 7/0 INCH DiAMETER MANDREL
E WIRE GROOVE MOST SEAT NOT LESS THAN I INCH DIAMETER MANDREL
~‘.TE l-’TOLE*A$CES
A.
1/04
INCH
5’ 1/32 INCH
C’ I/IS
INCH
051/1 INCH
£53/IS INCH
F. 1/4 INCH
3
•
3/0 INCH
N’ I/f
3~~I’4
INCH
K’ I INCH
~sO INCH
INCH
USE OF A SINGLE LETTER INDICATES THE SAME PLUS OR MINUS TOLERANCE, FOR EXAMPLE, A~PLUS ~a MINUS I/Os INCH.
IERE TWO LETTERS ARE USED, THE FIRST INDICATES THE P1.00 TOLERANCE AND THE SECOND INDIGA~TES THE MINUS
~4
~)LERANCE, FOR EXAMPLE. AX • PLUS
2, 1957
/04 INCH, MINUS 0 INCH.
4