Your Reliable Electrical Insulator Manufacturer in China

Being a professional manufacturer over 20 years, we are committed to offer you a wide range of electrical insulator and insulator string with a highest quality and best possible cost, with an added value of

Technical consulting at very beginning of your project

Individual Designs for your projects

On-site technical support and training

What is an Electrical Insulator

Electrical Insulators are essential components in power systems, such as power plants, power transmission and distribution lines, as well as their associated substations and some electrical equipments. These insulators are designed to withstand voltage and mechanical stress, and are available in various types and shapes. Normally, it has glass insulator, porcelain insulator and composite polymer insulator. Although the structure and appearance of different types of insulators are quite different, they are all composed of two parts: an insulating part and a connecting fitting. PowerTel and its related factories can offer a wide range of electrical insulator and insulator string for use on power plants, power transmission & distribution lines and its associated substations up to 500 kV. We aim to provide you a package solution that are reliable, easy to install, and meet the highest standards of quality and performance at your lowest cost. We test and verify the electrical insulators and strings of insulators in accordance with international standards such as IEC, DIN, and ANSI. and we offer an on-site technical support and training for the installation & maintainance of these electrical insulators and insulator string.

Electrical Insulator by its material

According to its raw materials, it has glass insulator, porcelain insulator and composite polymer insulator.

Glass Insulator

Up to 300 kN breaking load

Glass Insulator

Lower cost compared to other types of electrical insulator

Glass Insulator

No hydrophobicity & High Dielectric Strength

Porcelain Insulator
Porcelain Insulator

High mechanical strength, up to 550 kN

Porcelain Insulator
Porcelain Insulator

High resistance to harsh environment

Porcelain Insulator
Porcelain Insulator

Low thermal conductivity

composite polymer insulator
Composite Polymer Insulator

Much lighter than porcelain or glass insulators

Composite Polymer Insulator
Composite Polymer Insulator

A higher corrosion resistance, due to their special coatings & materials

Composite Polymer Insulator
Composite Polymer Insulator

An excellent pollution-resistance, strong prevention from flash accident

Electrical Insulators by its function

According to its function, it would be Suspension Insulators,Guy Strain Insulator, Line Post Insulators, Shackle Insulators, Substation Post Insulators,Bushing Insulators, Cap and Pin Insulators and Crossarm Insulators etc.

Product Feature Box

ISO 9001 Certificated Factory
ISO 9001 Certificated Factory
KEMA Cerficated
KEMA Cerficated Electrical Insulator
Custom desgin
Custom Design to Fit your Project
Over 20 years experience
Over 20 years Manufacturing Experience

Individual Design for your Project

Over 50 expert engineers are ready to provide the right solutions to all of your challenges for electrical insulator and work closely with your engineers for a specific design.

Custom Design
Testing Facilities

In-house Testing Facilities

We use our own internal testing facilities to ensure that all electrical insulators are of the highest quality before shipment. Routine and sample testing is conducted as well.

Custom Insulator String

Through years of experience , we can provide you a tailored insulator string solutions for all types of electrical towers & poles, and its associated tension & suspension clamps for conductors; these insulator strings will be pre-assembled and tested before the shipment.

Insulator String

Advantages of a Composite Polymer Electrical Insulator

Composite Polymer Insulator
Composite Polymer Insulator

The epoxy glass fiber rod has excellent antipollution properties, making it capable of preventing flash accidents and eliminating the need for cleanup in heavily polluted areas, while also providing superior electrical performance and strong mechanical strength for reliable and safe operation;

To optimize the size design of the shed type structure based on aerodynamic principles, reasonably disposing the grading ring can prevent electric current leakage, protect the surface from corrosion due to electric arcs, and increase the service life of a composite electrical  insulator;

This shed has excellent sealing performance and anti-electrolytic corrosion properties. It is designed for use in temperatures ranging from -40℃ to +50℃ and has excellent anti-ageing and corrosion resistance, as well as excellent resistance to brittleness and creep deformation, and an unbreakable, anti-bending property. Additionally, it is lightweight and small in size, making it easy to transport and install.

The composite electrical insulator has better mechanical and electrical performance than other types of insulator , and its safe operating tolerance is substantial.

Our Dip-coating Process for Porcelain Electrical Insulator

It is a newest process technology for manufacturing porcelain electrical insulator, mechanical equipment is used to coat ceramic insulators with RTV coating. This immersion coating results in a smooth and flat surface on the insulators, without accumulation or bubbles, and no dripping in the joints. The coating thickness is uniform and the appearance quality of products produced by this method is superior to that of insulators produced by spraying and brushing technology. Additionally, production is highly efficient and costeffective, and there is no environmental impact or safety hazards to operators in the production process, meeting the requirements of factory production.

Shackle Insulator
Line Post Insulators
Certificated by
Approved & Certificated by
  • “PowerTel stands out due to their first-class technical support and project management. Their dedication to their customers is unparalleled, always going above and beyond.”

    Louis from Ecuador

Related Product

Testing Items for a composite polymer electrical insulator

  1. Routine test : Mechanical routine test & visual verification
  2. Sample test: Verification of dimensions, end fittings and tightness of the interface between end fittings and insulator housing and of the specified mechanical load; Galvanizing test
  3. Type test: Dry lightning impulse withstand voltage test; wet power frequency test and wet switching impulse withstand voltage test for electrical insulators applied for the voltage level over 300 kV.
  4. Assembled core load-time test: Determination of the average failing load of the core of the assembled electrical insulator and control of the slope of the strength-time curve of an electrical insulator.
  5. Design tests: Tests on interfaces and connections of end fittings; Pre-stressing-Sudden load release pre-stressing ;Thermal-mechanical pre-stressing; Water immersion pre-stressing; Steep-front impulse voltage test; Dry power-frequency voltage test
  6. Tests on shed and housing material
    Hardness test; Accelerated weathering test; Tracking and erosion test; Flammability test7. Tests on the core material
    Dye penetration test; Water diffusion test