H1: XHP-120 Insulator — 120kN Fog‑Type Porcelain Suspension Insulator for Heavily Polluted Overhead Lines
XHP-120 Insulator is a specially designed fog‑type suspension insulator for medium‑ to high‑voltage overhead transmission lines located in heavily polluted environments such as coastal sand‑fill areas, chemical industrial zones, and desert regions.
Manufactured in compliance with IEC, BS, and AS standards, this XHP-120 Insulator features an extra‑long creepage distance of 432mm and a deep‑groove profile that keeps the underside dry and effectively suppresses power‑frequency arcing. Its cap‑and‑pin construction ensures stable mechanical performance under extreme temperature cycling from -40°C to +105°C.
Whether used in salt‑fog coastal areas, chemical plants, or arid desert regions, the XHP‑120 Insulator offers unparalleled pollution‑flashover resistance and long‑term reliability. For project engineers facing severe contamination challenges and demanding mechanical requirements, the XHP‑120 Insulator provides a robust and cost‑effective solution with a high mechanical strength of 120kN.
H2: XHP-120 Insulator Technical Specifications
The XHP-120 Insulator has a rated combined mechanical and electrical (M&E) failing load of 120kN (27,000 lbf), making it suitable for heavy‑duty transmission applications, including areas with significant ice loading and long spans.
Its standout feature is the large protective creepage distance of 432mm, which is significantly higher than standard insulators of the same diameter, providing superior performance in polluted conditions.
The 50% impulse flashover voltage is 125kV, effectively preventing lightning‑induced flashovers. The disc diameter is 254mm (10 inches), and the unit spacing is 146mm (5‑3/4 inches). The coupling hardware complies with IEC 120 & 471 standard 16B type, ensuring full interchangeability with standard fittings.
Standard glaze colors are brown, light gray, or blue. The porcelain body is manufactured by the wet process, and zinc‑sleeve pins are optionally available upon request.
Complete XHP-120 Insulator Technical Data per IEC, BS, and AS Standards:
| S/N | Parameter | Value |
| 1 | Type / Model | XHP‑120 |
| 2 | Glaze Color | Brown / Light Gray / Blue |
| 3 | Porcelain Disc Diameter, D (mm) | 254 |
| 4 | Unit Spacing, H (mm) | 146 |
| 5 | Standard Coupling to IEC 120 & 471 | 16B |
| 6 | Creepage Distance (mm) | 432 |
| 7 | Combined M&E Strength (kN) | 120 |
| 8 | Routine Test Load (kN) | 48 |
| 9 | Power Frequency Flashover Voltage – Dry (kV) | 90 |
| 10 | Power Frequency Flashover Voltage – Wet (kV) | 50 |
| 11 | 50% Impulse Flashover Voltage (kV) | 125 |
| 12 | Power Frequency Withstand Voltage – Dry (kV) | 80 |
| 13 | Power Frequency Withstand Voltage – Wet (kV) | 45 |
| 14 | Impulse Withstand Voltage (kV) | 115 |
| 15 | Power Frequency Puncture Voltage (kV) | 120 |
| 16 | Net Weight, Each, Approx. (kg) | 7.8 |
| 17 | Applicable Standards | IEC, BS, AS |
Note: The XHP series are fog‑type insulators with deep‑groove design for enhanced pollution performance. Alternative creepage distances, diameters, or unit spacings can be provided upon request.
H2: XHP-120 Insulator Material & Construction
Every unit of the XHP-120 Insulator is made from high‑grade alumina porcelain, fired at over 1,300°C to achieve maximum density and near‑zero porosity. The cap is produced from malleable cast iron, and the pin from hot‑dip galvanized steel — both providing excellent corrosion resistance.
The cement bonding between porcelain and metal parts uses high‑quality Portland cement, ensuring stable mechanical performance under extreme thermal cycling from ‑40°C to +105°C.
The deep‑groove profile is specifically designed to keep the lower surface dry during wet conditions, reducing leakage currents and preventing flashovers. The hard, glossy glaze coating offers good self‑cleaning properties, further reducing maintenance frequency. For more on porcelain manufacturing standards, visit the International Electrotechnical Commission (IEC).
H2: XHP-120 Insulator Applications & Installation
The XHP-120 Insulator is ideal for 33kV to 138kV AC overhead transmission lines located in areas with heavy salt‑fog, chemical pollution, or sandstorms. It is also used in distribution networks and substation entry towers where extra creepage distance is critical.
With a 120kN M&E rating, it offers the highest mechanical strength in the XHP series, making it suitable for the most demanding conditions such as very long spans, heavy ice loads, and high wind areas. Typical string configurations are:
- 33kV — 2 to 3 discs per string
- 69kV — 4 to 5 discs per string
- 115kV — 7 to 8 discs per string
- 138kV — 8 to 9 discs per string
It can be assembled into single, double, tandem, or V‑strings to meet various tension and suspension requirements. Whether for coastal grid upgrades or industrial plant power supply, the XHP-120 Insulator offers enhanced pollution performance and long‑term durability. Standard coupling dimensions (16B) ensure full compatibility with existing IEC fittings, sockets, and yokes.
For live‑line maintenance, it allows easy hot‑stick handling, reducing outage time during replacement. Optional arcing horns and grading rings are available to optimise voltage distribution along the string.
Explore our full range of suspension insulators and transmission hardware for more options.
H2: XHP-120 Insulator Quality & Performance Advantages
Compared to standard insulators, the XHP-120’s extended creepage distance and deep‑groove design provide superior resistance to pollution flashover, making it the preferred choice for severe environments. Its hydrophobic glaze reduces continuous water film formation, and the deep grooves keep the undersurface dry, significantly raising the pollution flashover voltage.
Moreover, the XHP-120 Insulator requires minimal routine maintenance and delivers a service life of over 50 years under normal operating conditions. Full testing procedures are detailed in IEC, BS, and AS standards. For installation guidance, refer to our insulator string assembly guide.
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 — such as temperature cycling, thermal‑mechanical performance, and radio interference voltage (RIV) — are also performed per applicable standards. Full test reports and traceability records are provided for each batch.
Each insulator is individually packed with foam cushioning and secured in sturdy wooden crates or corrugated cartons to prevent transit damage. We offer flexible shipping options (FOB, CIF, EXW) with lead times of 15‑30 days depending on order quantity.
For detailed datasheets, CAD drawings, or competitive pricing on the XHP‑120 Insulator, please contact our sales team via the inquiry form below. We also offer OEM services and free technical consultation for string assembly design.
H2: Why Choose Our XHP‑120 Insulator
When selecting an XHP‑120 Insulator for your transmission project in polluted areas, quality and reliability are paramount. Our XHP‑120 Insulator is subject to strict quality control at every production stage — from raw material inspection to final electrical testing.
We understand that pollution flashovers can cause costly outages, which is why each XHP‑120 Insulator is designed with extra creepage and deep grooves for maximum protection. With over a decade of experience in porcelain insulator manufacturing, we provide competitive pricing, fast delivery, and dedicated technical support.
Whether you need a small sample batch or a full container order, our XHP‑120 Insulator is available with short lead times. Contact us today to learn how the XHP‑120 Insulator can enhance your grid reliability in harsh environments.
