H1: ANSI 56-4 Insulator — 13.6kN Porcelain Pin-Type Insulator for Distribution Lines
ANSI 56-4 Insulator is a high‑voltage pin‑type porcelain insulator designed for medium‑voltage overhead distribution lines, offering the largest creepage distance and high mechanical strength for demanding applications. Manufactured in accordance with ANSI C29.6 standards, this ANSI 56-4 Insulator delivers reliable electrical insulation and mechanical endurance for distribution networks, particularly in areas with heavy conductor loads, long spans, or severe pollution conditions. Its pin‑type construction ensures easy mounting on line poles and stable performance under extreme temperature cycling from ‑40°C to +105°C. Whether used in industrial zones, coastal areas with salt fog, or regions with heavy pollution, the ANSI 56‑4 Insulator provides a cost‑effective and durable insulation solution for distribution infrastructure.
H2: ANSI 56-4 Insulator Technical Specifications
The ANSI 56‑4 Insulator has a cantilever strength of 13.6kN (3,000 lbf), suitable for high‑voltage distribution with heavy loads and long spans. Its creepage distance is 686mm (27 inches), offering superior pollution flashover performance. The dry arcing distance is 286mm (11.25 inches). The disc diameter is 305mm (12 inches), and the height is 241mm (9.5 inches). The minimum pin height is 254mm (10 inches). The insulator uses standard pin type mounting with J‑Neck and 1‑3/8 inch pin hole diameter, fully interchangeable per ANSI requirements. Standard glaze colors are grey or brown.
Complete Technical Data (both glaze colors):
| S/N | Technical Standard Particulars/Details | Brown | Gray |
| 1 | Product Item No./SKU Code | 56-4B | 56-4G |
| 2 | Glaze Color | Brown | Gray |
| 3 | ANSI Class | 56-4 | 56-4 |
| 4 | Figure No. | 1 | 1 |
| 5 | Connecting hardware coupling | Pin | Pin |
| 6 | Disc diameter D/in.(mm) | 12 (305) | 12 (305) |
| 7 | Unit Spacing H/in.(mm) | 9.5 (241) | 9.5 (241) |
| 8 | Leakage distance /in.(mm) | 27 (686) | 27 (686) |
| 9 | Cantilever strength /lb(kN) | 3000 (13.6) | 3000 (13.6) |
| 10 | Tension proof /lb(kN) | — | — |
| 11 | Impact strength /in‑lb(N‑m) | — | — |
| 12 | Low‑frequency dry flashover voltage (kV) | 140 | 140 |
| 13 | Low‑frequency wet flashover voltage (kV) | 95 | 95 |
| 14 | Critical impulse flashover voltage, Positive (kV) | 225 | 225 |
| 15 | Critical impulse flashover voltage, Negative (kV) | 310 | 310 |
| 16 | Low‑frequency puncture voltage (kV) | 185 | 185 |
| 17 | Radio‑influence voltage data‑RIV (Test voltage to ground)（kV） | 30 | 30 |
| 18 | Radio‑influence voltage data‑RIV (Max. RIV at 1000kHz)（μV） | 200 | 200 |
| 19 | Net weight (kg) | 10.8 | 10.8 |
| 20 | Applicated Standard | ANSI C29.6 | ANSI C29.6 |
H2: Material & Construction
Every unit of the ANSI 56‑4 Insulator is made from high‑grade porcelain, fired at high temperature to achieve maximum density and near‑zero porosity. The pin is manufactured from hot‑dip galvanized steel, providing excellent corrosion resistance. The cement bonding between porcelain and metal parts uses high‑quality cement, ensuring stable mechanical performance under extreme thermal cycling from ‑40°C to +105°C. The hard, glossy glaze coating offers good self‑cleaning properties, reducing maintenance frequency. For more on porcelain manufacturing standards, visit the International Electrotechnical Commission (IEC).
H2: ANSI 56-4 Insulator Applications & Installation
The ANSI 56‑4 Insulator is widely used on medium‑ to high‑voltage overhead distribution lines, typically at 46kV system voltage. It is ideal for heavy‑duty feeders, industrial power supply, coastal areas with salt fog, heavy pollution zones, long‑span rural projects, and urban distribution networks. The pin‑type design allows easy mounting on line poles using standard pin hardware. Standard dimensions ensure compatibility with existing pin bases and cross‑arms. Explore our full range of suspension insulators and transmission hardware for more options.
H2: ANSI 56-4 Insulator Quality & Performance Advantages
Compared to polymer alternatives, porcelain offers unmatched resistance to UV radiation, bird pecking, and scratch damage. Its glaze reduces continuous water film formation, significantly raising pollution flashover voltage. The ANSI 56‑4 Insulator requires minimal maintenance and delivers a service life of over 30 years under normal conditions. Full testing procedures are detailed in ANSI C29.6, published by NEMA.
Every unit undergoes 100% routine electrical and mechanical testing before dispatch, including visual inspection, dimensional checks, mechanical load tests, and high‑voltage withstand tests. Prototype tests — temperature cycling, thermal‑mechanical performance, and RIV — are also performed per ANSI C29.6. Full test reports and traceability records are provided. For installation guidance, refer to our insulator string assembly guide.
Each insulator is individually packed with foam cushioning and secured in sturdy wooden crates or cartons. We offer flexible shipping (FOB, CIF, EXW) with lead times of 15‑30 days. For datasheets, CAD drawings, or pricing, contact our sales team. We also offer OEM services and free technical consultation.
H2: Why Choose Our ANSI 56‑4 Insulator
When selecting an ANSI 56‑4 Insulator, quality and reliability are paramount. Our product undergoes strict quality control from raw material to final testing. We understand outage costs, so each insulator is designed for long‑term durability. With years of experience, we provide competitive pricing, fast delivery, and dedicated support. Whether sample or full container, our ANSI 56‑4 Insulator is available with short lead times. Contact us today to learn how it can enhance your grid reliability.
