What Huahao Makes and Who It Is For
What We Make
Glazed porcelain insulators for overhead transmission and distribution lines and for substation apparatus, covering suspension discs, strain insulators, spool insulators, pin type insulators, line post insulators and station post insulators.
Who We Serve
Utility procurement engineers, transmission and distribution line contractors, substation EPC contractors and electrical wholesalers in more than 40 countries.
The Problem We Solve
Insulator enquiries fail on the detail: a coupling that does not match the tower hardware, a mechanical rating quoted without the units, a leakage distance missing from the data sheet, or a profile that no catalogue covers. We publish the full figures for every class we make and design the part when no class fits.
Why Buyers Choose Huahao
Production technology for designs up to 500kV AC and 400kV DC, six standards families from one plant, an ISO 9001:2008 certified quality system, and engineers who will work through your specification before you commit to a class.
Six Product Families From One Plant

Station Post Insulators
Porcelain station post insulators designed for substation applications, available in IEC C4-125 and ANSI TR-208 standard configurations. Built to withstand mechanical and electrical stresses in high-voltage environments. Supports system voltages up to 500kV AC and 400kV DC. Engineered for use in rigid conductor support and busbar insulation within substations.

Line Post Insulators
A porcelain line post insulator to ANSI 57-2 with a fixed mounting base, used to support overhead conductors at substations, distribution poles, and terminal structures. The insulator provides mechanical cantilever strength and electrical insulation in a rigid, non-flexing configuration. Designed for 35kV AC system voltage with a dry flashover rating of 110kV and wet flashover of 85kV. The 559mm leakage distance supports pollution-resistant performance in coastal and industrial environments.

Pin Type Insulators
A porcelain pin type insulator to ANSI 56-3 and ANSI 55-4 standard designs, used in overhead distribution and transmission lines to support conductors on poles and towers. Each insulator is designed for a specific system voltage and mechanical load. The high voltage version is rated for 34.5kV application and the medium voltage version for 13.2kV. Both have a cantilever strength of 3,000 pounds (13.6kN).

Suspension Insulators
Porcelain suspension insulators for overhead transmission and distribution lines and substations, built to ANSI, GB, BS, DIN, AS and IEC standard designs. Supports system voltages up to 500kV AC and 400kV DC. Designed for standard and non-standard applications with engineering support available.

Strain Insulators
A porcelain strain insulator to ANSI 54-3 with a threaded coupling, used in tension strings on overhead transmission and distribution lines. The insulator is designed for mechanical load transfer and electrical isolation in line termination, anchor, and angle tower applications. It is built to ANSI and IEC standard dimensions and electrical ratings.

Spool Insulators
A porcelain spool insulator to ANSI 53-2 with a cylindrical body and metal cap, used in overhead transmission and distribution lines and in substation equipment. The insulator provides electrical isolation between conductors and grounded structures. It is designed for use in moderate voltage applications where mechanical strength and electrical performance are required in a compact form. The body is glazed porcelain with a metal cap cemented at the top. It is built to ANSI standard dimensions and electrical ratings.
Every Product We Make

Station Post Insulators IEC C4-125

Station Post Insulators ANSI TR-208

Line Post Insulators ANSI 57-2

High Voltage Pin Type Insulators ANSI 56-3

Medium Voltage Pin Type Insulators ANSI 55-4

Strain Insulators ANSI 54-3

Spool Insulators ANSI 53-2

Clevis Type Suspension Insulators ANSI 52-4
Insulators as They Leave the Plant












Photographs of production units. The class and year markings fired into the glaze are visible on many of them.
Where Our Insulators Go to Work

Overhead Transmission Lines
Porcelain insulators for overhead transmission and distribution lines and substations, manufactured to GB, ANSI, BS, DIN, AS and IEC standard designs. Supports system voltages up to 500kV AC

Power Distribution Networks
Porcelain insulators for overhead distribution networks, designed to ANSI standard dimensions and rated for specific system voltages. Built for use on pole lines in urban, rural and industri

Substations
Porcelain station post insulators for substation busbar support, designed to IEC C4-125 and ANSI TR-208 standards. Used in high-voltage substations to isolate live conductors from grounded s
How We Work With Buyers

Custom and Non Standard Insulator Design
When no published class fits the structure we design the insulator around the duty instead of forcing the nearest catalogue part into the drawing.

Standard Design Supply to GB ANSI BS DIN AS and IEC
Six standards families from one plant so a multi market tender does not become a multi supplier tender.

Export Supply for Utilities and Contractors
Insulators already in service across more than 40 countries and every climate zone our customers work in.
Inside the Plant



Technical Guides for Specifying Engineers

ANSI and IEC Porcelain Insulator Standards Compared
How ANSI classes like 52-4 and 57-2 and IEC designations like C4-125 describe a porcelain insulator, and what to check on a data s

How to Read ANSI Insulator Class Numbers
Learn how ANSI class numbers like 52-4, 56-3 and 57-2 identify porcelain insulators, and how they differ from IEC designations suc

Creepage Distance and Pollution Performance
Creepage distance values for IEC C4-125 (500mm), ANSI TR-208 (610mm), ANSI 57-2 (559mm), and ANSI 56-3 (533mm) insulators. How to

Flashover Voltage Explained Dry Wet and Impulse
Understanding dry flashover, wet flashover, impulse flashover, puncture voltage, and impulse withstand voltage in porcelain insula
Questions Buyers Ask First
If your question is not here, email it. A specification is easier to discuss in writing than through a contact form.
What types of porcelain insulator do you manufacture
Suspension discs, strain insulators, spool insulators, medium and high voltage pin type insulators, line post insulators and station post insulators, covering ANSI classes 52-4, 53-2, 54-3, 55-4, 56-3 and 57-2 plus IEC C4-125 and ANSI TR-208.
What is the highest voltage you can design for
Our production technology supports insulator designs up to 500kV AC and 400kV DC system voltages.
Which standards do you build to
GB, ANSI, BS, DIN, AS and IEC standard designs, and non-standard designs developed by our engineers where no published class fits.
Do you publish full mechanical and electrical figures
Yes. Every product page lists the dimensions, mechanical values and electrical values in both imperial and metric units, and each has a downloadable datasheet.
What certification do you hold
Our manufacturing facilities are certified to ISO 9001:2008. We do not claim any other certification.
How do I get a quotation
Email [email protected] with the class, the coupling type, the quantity and the destination, or call +86-799-7555689. There is no form on this site because a specification is easier to discuss by email.
Send Us the Class and We Will Send You the Figures
Tell us the ANSI or IEC class, the coupling type, the quantity and the destination. If no published class fits your structure, send the drawing instead and our engineers will work through it.
