Pin Type Insulators
ANSI C29.5 & C29.6
Wet-process porcelain pin type insulators with matching hot-dip galvanized steel spindles. Low voltage (55 series) and high voltage (56 series). Six international standard systems from our Zibo heritage production base. For distribution and sub-transmission lines from 1 kV to 33 kV.
Pin Type Insulators — Full Series Data with Spindles
ANSI C29.5 — Low & Medium Voltage Pin (55 Series)
| Class | D (mm) | H (mm) | Creepage | Cantilever | Dry FO | Wet FO | Impulse+ |
|---|---|---|---|---|---|---|---|
| 55-1 | 83 | 83 | 102 mm | 13 kN | 35 kV | 20 kV | 50 kV |
| 55-2 | 95 | 83 | 127 mm | 11 kN | 50 kV | 25 kV | 75 kV |
| 55-3 | 121 | 95 | 178 mm | 11 kN | 65 kV | 35 kV | 100 kV |
| 55-4 | 140 | 111 | 229 mm | 13 kN | 70 kV | 40 kV | 110 kV |
| 55-5 | 178 | 124 | 305 mm | 13 kN | 85 kV | 45 kV | 140 kV |
ANSI C29.6 — High Voltage Pin (56 Series)
| Class | D (mm) | H (mm) | Creepage | Cantilever | Dry FO | Wet FO | Impulse+ |
|---|---|---|---|---|---|---|---|
| 56-1 | 191 | 146 | 330 mm | 11 kN | 95 kV | 60 kV | 150 kV |
| 56-2 | 229 | 165 | 432 mm | 13.2 kN | 110 kV | 70 kV | 175 kV |
| 56-3 | 267 | 191 | 533 mm | 13.2 kN | 125 kV | 80 kV | 200 kV |
| 56-4 | 305 | 241 | 685 mm | 13.2 kN | 140 kV | 95 kV | 225 kV |
| 56-5 | 343 | 318 | 864 mm | 13.2 kN | 175 kV | 125 kV | 270 kV |
Matching Spindles — ANSI Standard
| Model | Type | H (mm) | D (mm) | Mech Load (kN) | Weight (kg) | For ANSI Class |
|---|---|---|---|---|---|---|
| C110M | M (Top Thread) | 330 | 76 | 11 | 1.9 | 56-1 |
| C111M | M (Top Thread) | 356 | 76 | 9 | 2.2 | 56-2 |
| C112M | M (Top Thread) | 407 | 89 | 10 | 2.5 | 56-3 |
| C113M | M (Top Thread) | 432 | 89 | 9 | 3.25 | 56-4 |
| C115T | T (Through Bolt) | 198 | 76 | 11 | 1.54 | 56-1 |
| C116T | T (Through Bolt) | 223 | 76 | 9 | 1.87 | 56-2 |
| C117T | T (Through Bolt) | 274 | 89 | 10 | 2.17 | 56-3 |
| C118T | T (Through Bolt) | 299 | 89 | 9 | 2.7 | 56-4 |
All spindles hot-dip galvanized forged steel. M-type = top-thread crossarm mounting; T-type = through-bolt crossarm mounting. Spindle model auto-matched to ANSI class on quotation.
IEC / AS / DIN / SA — Representative Pin Type Models
| Standard | Model | D (mm) | H (mm) | Creepage | Cantilever | Wet FO | Dry FO |
|---|---|---|---|---|---|---|---|
| IEC | P-22-Y | 230 | 165 | 432 mm | 11 kN | 70 kV | 125 kV |
| IEC | P-33-Y | 279 | 244 | 630 mm | 13.8 kN | 90 kV | 170 kV |
| AS 2947.2 | ALP/22/450 | 160 | 200 | 450 mm | 11 kN | 50 kV | — |
| AS 2947.2 | ALP/33/710 | 220 | 265 | 710 mm | 11 kN | 90 kV | — |
| DIN | D10K47 | — | — | — | — | 65 kV | 90 kV |
| SA | CN46 | 160 | 160 | 320 mm | 1800 dan | 65 kV | 85 kV |
Full IEC range includes common glaze and semiconductor glaze variants. AS models feature AS-standard head dimensions (Fig.10). DIN and SA models available on request with full engineering data. Contact us with your project standard for confirmation.
Spindle Configuration Guide
Every pin insulator ships with a dimensionally matched spindle. Pin-spindle fit is guaranteed per standard — no separate sourcing required.
Where Pin Type Insulators Are Used
LV/MV Distribution Lines
1 kV – 15 kV overhead distribution networks. Urban, suburban, and rural electrification on wood, concrete, and steel poles. ANSI 55 series is the standard choice for pin-mount configurations.
HV Distribution & Sub-Transmission
15 kV – 33 kV lines connecting substations to distribution networks. ANSI 56 series with extended creepage for pollution zones. Often paired with line post insulators on the same project.
Multi-Standard International Projects
EPC projects spanning ANSI and IEC regions. Pin insulators manufactured to six different standard systems from our Zibo heritage production base — eliminating the need for multiple suppliers and multiple qualification cycles.
Pin Type Insulator FAQ
ANSI C29.5 covers low and medium voltage pin insulators (classes 55-1 to 55-5, rated up to 15 kV system voltage). ANSI C29.6 covers high voltage pin insulators (classes 56-1 to 56-5, rated 15 kV to 33 kV). The 56 series has larger body diameter, greater creepage distance, and higher flashover voltage ratings. Both series use the same porcelain body material (C-130 grade) and hot-dip galvanized steel spindles.
Yes. Every pin insulator is supplied with a dimensionally matched hot-dip galvanized forged steel spindle. We manufacture both M-type (top thread, models C110M–C114M) and T-type (through bolt, models C115T–C120T) spindles in-house. Pin-spindle fit is guaranteed per ANSI class — no separate sourcing required. BS and AS standard spindles are also available.
For a 22 kV distribution system, ANSI Class 56-2 is the standard choice (70 kV wet flashover, 432 mm creepage). In polluted environments — coastal, industrial, or desert — specify Class 56-3 (80 kV wet flashover, 533 mm creepage) for additional pollution performance margin. The rule of thumb: your wet flashover voltage should be at least 2× your maximum phase-to-ground operating voltage.
Yes. In addition to ANSI C29.5 and C29.6, we manufacture pin type insulators to IEC standard (with common and semiconductor glaze options), AS 2947.2 (Australian standard with AS-specific head dimensions), DIN standard (D10K series for European projects), and SA standard (CN series for South African projects). Specify your applicable standard on your RFQ and our engineers will confirm the correct product series within 6 hours.
Standard ANSI 55 and 56 series configurations: 8–12 weeks from order confirmation. Minimum order quantities are flexible for first orders — contact us with your project quantity for confirmation. Pin + spindle bundle pricing is available, and we can accommodate multi-standard orders in a single shipment.
Get a Technical Proposal for Pin Type Insulators
Specify your ANSI class, quantity, and spindle type. Our engineers respond within 6 hours with pin + spindle bundle pricing, lead time, and applicable test reports.