G11 Glass Epoxy Sheets Manufacturer in India
The G11 Glass Epoxy is an innovative laminate made from fiberglass reinforced epoxy which has the advantage of being more heat resistant and mechanically strong than normal G10 or FR-4 laminates. The name G11 used by various industrial sectors to denote the laminate as per the standard classification of NEMA, is a non-flame retardant laminate.
As a reputed G11 Glass Epoxy supplier in India, Harnawa Inc. provides internationally certified quality tested G11 fiberglass insulation laminate sheets to manufacturers of transformers, motors, generators, switchgears and PCBs from our state-of-the-art facility based out of Mumbai, India.
What is G11 Glass Epoxy?
G11 is produced by saturating several layers of woven fiberglass cloth with a high-temperature epoxy resin system, after which the whole laminate structure is cured under controlled heat and pressure. This results in the production of a stiff, dense laminate plate whose structure resembles that of G-10 and FR-4 but tailored for use at higher temperatures.
While FR-4 is classified as a flame-retarding laminate plate, G11 does not have any flame retardant certification, as the epoxy resin system used is engineered only for temperature and mechanical purposes without any consideration of fire safety. Therefore, G11 would be an ideal option for applications where thermal resistance and mechanical properties are prioritized over flame retardancy.
G11 High Temp Epoxy Sheet — Heat Resistance & Performance
For an epoxy sheet with high temperature resistance classification, G11 can function continuously in temperatures of up to about 200°C, which is a marked improvement on the 170°C that FR-4 can withstand. As such, G11 is the perfect material to use in components that work under high heat for long periods of time, such as high-load transformers, industrial motors, and machines that must work in difficult thermal conditions.
G11 maintains its mechanical strength and dielectric properties under high heat much more effectively than lower-grade epoxies and phenolic materials do.
Flame Retardancy
G11 is categorized under non-flame retardant grade material. It is a crucial point to consider while deciding the material required for your specific application; when safety from fire is an absolute requirement (such as in enclosed switchgear or panelboards that have standards related to flammability), you should select FR-5, which is the flame-retardant version of G11. G11 is still the preferred material for high-temperature applications.
Color & Visual Identification
G11 material is usually delivered in the unique yellow-green to amber shade, which helps it be easily distinguished from the conventional yellow surface that characterizes G-10 and FR-4. Such a practice is common in the industry and ensures easy identification of the material grade by the purchase and production departments.
Material Construction
G11 is made by using woven fiberglass cloth that has been strengthened using epoxy resin in such a way that it is similar to the construction used in the production of G-10 and FR-4, but its resin composition is different since it is formulated to have high glass transition temperature and retain mechanical properties under thermal stress.
Thickness & Size Availability
G11 sheets can be provided by Harnawa Inc. in customized thicknesses according to the requirements of your application with the option of cut-to-size sheets, which save machining time and minimize material wastage.
Typical Applications of G11 Fiberglass Insulation Laminate Sheet
Use of G11 Fiberglass Insulation Laminate Sheets is specified in numerous applications requiring high temperature resistance such as:
- Production of Switchgears
- Insulating boards and partitions used in the assembly of high temperature switchgears
- Busbars that require insulation in high temperature conditions
Manufacture of Printed Circuit Boards (PCBs)
Substrates for use in printed circuit boards requiring high-temperature or high-reliability applications
Manufacture of Transformers
- Insulating structural components in transformers subjected to continuous high temperatures
- Insulation of terminal boards and clamps of transformers
Construction of Motors & Generators
- Insulation material in motors and generators that operate continuously at high temperatures
- Slot wedges, end winding support, and structural spacers for tough thermal applications
Applications in Industrial & High Temperature Environments
- Equipment insulation in the oil and gas industry
- Metallurgical and chemical processing machinery
- High temperature aerospace insulation components
NEMA G11 vs Other Glass Epoxy Grades
| Property | G-10 | FR-4 | G11 | FR-5 |
| Base Construction | Fiberglass + Epoxy | Fiberglass + Epoxy | Fiberglass + Epoxy | Fiberglass + Epoxy |
| Heat Resistance | Up to 155°C | Up to 170°C | Up to ~200°C | Up to 200°C |
| Flame Retardancy | Not flame-retardant | Flame-retardant | Not flame-retardant | Flame-retardant |
| Color | Yellow | Yellow | Yellow-green to amber | Yellow-green to amber |
| Best Suited For | General-purpose insulation | Fire-safety-critical applications | High-temperature, non-fire-rated applications | High-temperature, fire-safety-critical applications |
Important point: In case where you need maximum possible heat resistance in glass epoxy laminate material without having any compliance issues in regards to flame resistance, then NEMA G11 is the best choice for you. However, in case where you have to comply with fire safety standards, then FR-5 is the right substitute for NEMA G11.
Building a Complete High-Temperature Insulation System
G11 rarely operates in isolation. In real-world transformer, motor, and switchgear assemblies, G11 sheets are combined with other high-temperature insulation materials to build a complete, multi-layer insulation system suited to demanding thermal environments:
- Aramid Papers — used for Class H and Class F slot lining and winding insulation, complementing G11 structural components in high-temperature motor and generator assemblies
- Laminated Insulation Paper Composites — layered dielectric barrier materials used alongside G11 in transformer and motor construction
- Insulation Tapes High Temperature — used for coil binding and terminal insulation in assemblies operating near G11’s rated temperature range
- Fiberglass Insulation Sleeves — used to protect leads and connections routed through or near G11 structural panels
- Polyimide film — offering additional high-temperature dielectric wrapping where extreme thermal resistance is required
- Fiberglass yarn — used for lacing and mechanically reinforcing windings in high-temperature equipment
- Insulating Varnishes and Thinner — applied over windings and components to complete the dielectric protection system in high-temperature motor and transformer builds
Sourcing all of these materials from a single, certified supplier ensures material compatibility, consistent quality standards, and simplified procurement for OEMs building high-reliability, high-temperature electrical equipment.
Quality & Certifications
Each shipment of our G11 Glass Epoxy Sheets produced by Harnawa Inc. has been manufactured and tested for adherence to international standards of quality based on:
- UL certification
- CE marking compliance
- RoHS compliance
- ISO 9001:2015 compliant production
- REACH compliance
The above guarantees that all of the G11 Sheets procured from us satisfy the specifications set forth by both domestic Indian companies and export-oriented OEMs.
G11 Glass Epoxy Sheets Manufacturer in India — Why Choose Harnawa Inc.
Harnawa Inc. is known to be among the most reputed producers of G11 Glass Epoxy in India, providing NEMA G11 fiberglass insulation laminate sheets along with various electrical insulating materials for transformers, motors, generators, switchgear, electric vehicle production, and electronics industries.
What sets us apart:
- Consistent supply of G11 grade laminate sheet up to around 200°C
- Tailored options for thickness & customized cut size possible
- Nationwide logistics support ranging from but not limited to Mumbai, Delhi, Pune, Ahmedabad, and others
- Certified quality system (UL, CE, RoHS, ISO 9001:2015, REACH)
- Comprehensive solution offering for G11 as well as other high temperature insulation materials
Frequently Asked Questions
1.What is the maximum working temperature of G11 glass epoxy sheets?
G11 can be operated at continuous temperatures of about 200°C, which makes it one of the best glass epoxy sheets that can operate at high temperatures.
2.Does G11 sheet have any flame-retardant properties?
No. G11 is not a flame-retardant grade. In case you need flame-retardant grade sheets in addition to high-temperature properties, then FR-5 must be considered.
3.How is G11 different from FR-4?
G11 has a better operating temperature (~200°C compared to FR-4 that is ~170°C) and superior mechanical strength at elevated temperatures. However, G11 lacks FR-4 flame-retardant rating.
4.Are the G11 sheets cut to size possible?
Yes. Harnawa Inc. provides G11 sheets that are customizable in terms of their thickness and can be cut to size.
5.In what industries are G11 fiberglass insulation laminate sheets used the most?
G11 is extensively used in high-temperature switchgears, production of PCB, manufacturing of transformers, insulation of motors and generators, and any equipment that operates at high temperature.
