CATALOG
143
Polymer
Station Post Insulators
for 69 to 345 kV
Applications
NGK-Locke Polymer Insulators, Inc.
Virginia Beach, Virginia, U.S.A.
NGK-Locke Polymer Insulators, Inc.
TABLE of CONTENTS
Station Post Insulators
Polymer Station Post Insulators..............................................................................
Application Guidelines for Polymer Station Posts (SP) ........................................
Catalog Number System ........................................................................................
Corona Ring Application ........................................................................................
Standard Strength Station Post Application with 2.5 Core ....................................
High Strength Station Post Application with 3.5 Core ..........................................
Research & Development ......................................................................................
Packaging ..............................................................................................................
1
2
3
3
4
5
6
6
NGK-Locke Polymer Insulators, Inc. management systems comply with the requirements of ISO
9001:2008 (Certificate #FM36580, since 1997) and ISO 14001:2004 (Certificate #EMS96014,
since 2005); the registrar for both certificates is BSIGroup America Inc., based in Reston, Virginia.
Polymer Station Post Insulators
NGK-Locke Polymer Insulators (NLPI) provides polymer station
post (SP) insulators that are manufactured using the same
unsurpassed designs, materials, and quality control used in our
polymer suspension & line post insulators. Our end fitting sealing
system employs double O-rings plus an RTV sealant that have
demonstrated excellent protection against moisture penetration.
The housing material is silicone rubber, which provides excellent
contamination performance. This housing is formed by compression
molding silicone rubber onto the core as one continuous part free of
any joints. Both housing and core are chemically bonded together
during the vulcanization process. The strength of this bond is
greater than the tearing strength of the silicone housing material
itself. End fittings are then assembled by a pressure controlled,
multi-step, crimping process. Overall length and hole alignment
are controlled by NLPIs unique design and manufacturing process.
Polymer SP Structure
NGK-Locke Polymer Insulators, Inc.
Station Post Insulators
This process provides the SP with more severe tolerances required for substation equipment. As
shown below, NLPIs polymer station post insulators have excellent seismic performance due to
their flexibility. NLPI produces polymer SP with a 2.5 and a 3.5 diameter solid core.
230kV, 3.5 SP (Bus Support)
Seismic Test on 230kV, 3.5 SP
in accordance with IEEE 693
69kV, 3.5 SP
Application Guidelines for Polymer Station Posts (SP)
NLPIs SP complies with dimensional and electrical values in accordance with ANSI C29.9
Technical Reference (TR) Number. The cantilever and tension strengths exceed the
required values of the ANSI standard. Compression and torsion strengths are given as
guaranteed values.
Specified Cantilever Load (SCL) is breaking load guaranteed by manufacturer and should
be less than Cantilever Breaking Load (CBL), which is the maximum load reached during a
cantilever breaking test.
The deflection values shown in this catalog correspond to the deflections measured at the
relevant ANSI TR porcelains Maximum Working Load (MWL is specified as 40% of the ANSI
TR porcelains cantilever strength).
SP for underhung applications are also available. Contact your NGK representative for
more information.
NGK-Locke Polymer Insulators, Inc.
Station Post Insulators
CATALOG NUMBER SYSTEM
S2 SN471 22 W
Type of
Insulator
S: Station
Post
Core Dia.
2: 2.5
4: 3.5
Shed Shape
N: Standard Leakage
G: Bigger Sheds on Both Ends
for 2.5 SP
H: Bigger Sheds on Both Ends
for 3.5 SP
Ring Mounting Detail
Design
Variation
Bottom
Flange
Base
Grading Ring Application
None: BIL750kV & below
W: 11 ring for 2.5 SP
X: 15 ring for 3.5 SP
Top Flange
Base
Corona Ring Application
W Grading Ring
Number
of Sheds
Recommended Mounting Direction
Opening Side
X Grading Ring
NGK-Locke Polymer Insulators, Inc.
Station Post Insulators
Standard Strength Station Post Application with 2.5 Core
TR
NGK
Catalog #
278
S2-SG191-21
*1
286
287
288
289
291
295
304
308
312
316
S2-SG311-21
S2-SN311-21
S2-SN361-21
S2-SN471-22-W
S2-SN551-22-W
BIL and
Impulse
Withstand,
kV
Height,
inch
Leakage
distance,
inch
550
30
45
78.9
350
650
750
900
1050
54
62
80
92
128
129
150
196
229
Cantilever
SCL*2,
K lbs.
Compression*3,
K lbs.
2.8
12.0
4.5
2.3
2.0
2.0
1.8
25.0
8.0
6.0
3.5
2.5
Deflection,
at TRs MWL*4
TRs
inch
MWL,
K lbs.
1.20
0.8
1.04
2.7
0.68
0.56
0.88
0.48
0.74
0.38
0.58
0.32
0.50
1.8
2.5
3.9
3.3
5
5.5
8.4
6.7
10.5
*1: ANSI Technical Reference Number
*2: Specified Cantilever Load was determined using high strength bolts.
Depending on the grade of bolt, a bolt failure may occur before core failure.
*3: Compression values are based on testing per the procedure specified in ANSI C29.9-1983 using fixed ends.
Actual application conditions may result in different compression strength values.
*4: Deflection measured at the relevant ANSI C29.9-1983 TR porcelains maximum working load.
PowerCritical Frequency
Max. RIV,
Impulse
Wet
Pos., kV Withstand, V/kV
kV
Approx.
Weight
lbs.
390
145
200/44
35
710
275
200/88
47
610
810
1010
1210
230
200/73
315
500/103
455
500/146
385
500/146
45
51
67
74
Tensile Strength: 25K lbs.
Torsion Strength: 30K in-lbs.
Height
Flange End Fitting Detail
S2-SN311-21
The dimensions are in inches.
The metric equivalents (millimeters)
are shown in ( ).
NGK-Locke Polymer Insulators, Inc.
Station Post Insulators
High Strength Station Post Application with 3.5 Core
TR*1
NGK
Catalog #
278
S4-SH151-22
286
S4-SH251-22
287
288
S4-SN311-22
289
291
S4-SN361-22
295
304
S4-SN461-11-X
308
312
S4-SN541-11-X
316
324
367*6 S4-SN641-13-X
369*6
330
371 S4-SN741-11-X
373
BIL and
Impulse
Withstand,
kV
Height,
inch
BCD,
inch
350
550
30
650
45
54
137
80
5, 7*2
204
1300
106
285
2.3
8.2
1470
122
5, 7*2
329
2.9
6.2
750
900
1050
62
92
5
5
5, 7*2
Leakage
distance,
inch
Cantilever
SCL*3,
K lbs.
Compression*4,
K lbs.
117
5.0
45.0
72.9
160
240
8.0
4.1
3.6
4.5
3.9
45.0
35.0
26.0
16.0
11.0
Deflection,
at TRs MWL*5
TRs
MWL,
inch
K lbs.
1.20
0.68
1.04
0.56
0.88
0.48
0.74
0.38
0.58
0.32
0.50
0.40
0.58
0.82
0.36
0.47
0.70
*1: ANSI Technical Reference Number
*2: The mechanical load was determined using a 7-inch BCD mounted specimen.
Care should be taken when a specimen is mounted using 5-inch BCD.
*3: Specified Cantilever Load was determined using high strength bolts.
Depending on the grade of bolt, a bolt failure may occur before core failure.
*4: Compression values are based on testing per the procedure specified in ANSI C29.9-1983 using fixed ends.
Actual application conditions may result in different compression strength values.
*5: Deflection measured at the relevant ANSI C29.9-1983 TR porcelains maximum working load.
*6: BCD at bottom flange is 5 inch though the porcelains TR specifies 7 inch BCD.
0.3
0.5
0.8
0.8
1.2
1.1
1.6
1.6
2.4
1.9
3.0
4.0
5.7
8.1
5.3
6.9
10.3
Critical
Impulse
Pos., kV
390
PowerFrequency Max. RIV,
Wet
V/kV
Withstand,
kV
610
710
810
1010
1210
Height
5
The dimensions are in inches.
The metric equivalents (millimeters)
are shown in ( ).
200/44
275
200/88
230
200/73
315
500/103
455
500/146
385
54
70
78
86
500/146
128
141
1410
525
1000/220
156
1610
590
1000/220
174
Tensile Strength: 25K lbs.
Torsion Strength: 55K in-lbs.
Flange End Fitting Detail
S4-SN541-11-X
145
Approx.
Weight
lbs.
NGK-Locke Polymer Insulators, Inc.
Research & Development
Station Post Insulators
The station post insulators were subjected to various mechanical, electrical, and aging tests to validate
the design. Some tests and the facilites are introduced in the following.
Cantilever Strength
Test
Torsion Strength Test
Critical Impulse Flashover Test
Packaging
Compression Strength Test
Low-Frequency Wet Withstand Test
All of NLPIs insulators are packed in weatherproof containers in order to protect the products during land,
air, and sea transportation. Several different grades of packaging can be offered depending on the mode
of transport and the expected storage conditions. The packaging options that we offer are 1) standard
grade/prefabricated packing, 2) economical grade/cardboard carton, and 3) best grade/closed wooden
crate. Since the user best knows their crate requirements, they should select the option that is most suited
to their needs and include that information in the purchasing specification. Special packaging
arrangements can be accommodated upon request.
Each container is marked with the number of insulators it contains, the catalog number, the
manufacturers name, and any other customer requests. Also, a Polymer Station Post Insulator Handling
Instruction sheet is included with all containers. This sheet states any necessary cautions during
handling, transportation, and installation. If corona rings are to be included, a corona ring installation
sheet is also provided.
NGK-Locke Polymer Insulators, Inc.
1609 Diamond Springs Road, Virginia Beach, Virginia 23455, U.S.A.
Tel: +1(757) 460-3649 Fax: +1(757) 460-3550
Website: www.ngk-polymer.com
Email:
info@ngk-polymer.com
NGK INSULATORS, LTD.
U.S.A.
Canada
NGK-Locke, Inc.
Atlanta Office
1880 West Oak Parkway, Suite 104
Marietta, Georgia 30062, U.S.A.
Tel: +1(404) 659-3153 Fax: +1(404) 524-6185
NGK Insulators Canada, Ltd.
Toronto Office
2700 Matheson Blvd. East,
Suite 700 East Tower,
Mississauga L4W 4V9, Ontario, Canada
Tel: +1(905) 602-1266 Fax: +1(905) 238-8247
Baltimore Office
2525 Insulator Drive
Baltimore, Maryland 21230, U.S.A.
Tel: +1(410) 347-1700 Fax: +1(410) 347-1724
Los Angeles Office
21250 Hawthorne Blvd., Suite 500
Torrance, California 90503, U.S.A.
Tel: +1(310) 316-3323 Fax: +1(310) 316-3944
Montreal Office
1501, Avenue McGill College
Bureau 515
Montreal (Quebec) H3A 3M8, Canada
Tel: +1(514) 281-8488 Fax: +1(514) 281-8596
All Other Countries
NGK Insulators, LTD
Add: 2-56, Suda-cho, Mizuho, Nagoya,
467-8530, Japan
Tel: +81-52-875-7511 Fax: +81-52-872-7530
Web: http://www.ngk.co.jp/english/index.html
pr-office@ngk.co.jp
