Why Coral Coil?
CORAL COIL is the only coil manufacturing company in India, to be certified with ISO 9001:2015, ISO 45001:2018, ISO 14001:2015. Already a member with EASA, CORAL procures and manufactures products from reputed suppliers that follow IEC manufacturing and testing procedures and IEEE standards for manufacturing and in-process testing.
Trusted Coil
Engineering
Experts
Tested & Proven at Manitoba Hydro – High Voltage Test Facility
At Coral, quality and reliability are the cornerstones of our engineering philosophy. We are proud to announce that our coils have successfully passed rigorous testing at the world-renowned Manitoba Hydro – High Voltage Test Facility in Winnipeg, Canada. This certification stands as a powerful endorsement of our product’s endurance, insulation integrity and compliance with global standards.
Test Highlights:
- Thermal Aging: Our coils underwent 500 thermal cycles ranging from –40°C to +155°C.
- Voltage Endurance: The coils were tested at 35 kV RMS (49.5 kV peak), 60 Hz and 100°C for 250 continuous hours.
- Diagnostic Evaluations: Comprehensive measurements were conducted before and during testing, including insulation resistance, partial discharge (PD), dissipation factor, capacitance, tap tests and surface resistance.
Standards Compliance:
Testing was conducted in full alignment with globally recognised industry standards:
- IEEE 1310-2012: Thermal Evaluation of Insulation Systems for AC Electric Machinery.
- IEEE 1043-1996: Voltage Endurance Testing of Form-Wound Bars and Coils.
- IEEE 1553-2002: Qualification of Form-Wound Stator Coils.
Precision Redesign Through Advanced 3D Scanning
At Coral Coil, we utilise advanced 3D scanning technology for precise coil replication and design optimisation, allowing us to capture detailed geometries and generate accurate manufacturing blueprints. This enables seamless adaptation, performance enhancement and exact fitment for replacement or upgraded coils.
By combining digital reconstruction with advanced engineering methodologies, we ensure high-precision manufacturing, improved efficiency and reduced turnaround times for custom coil solutions.
Expertise In Coil Manufacturing
Decades of expertise in coil manufacturing for critical applications.
State-of-the-art infrastructure with precision engineering capabilities.
Comprehensive in-house testing for reliability and safety assurance.
Custom design and engineering support for unique customer requirements.
Proven track record in executing large-scale coil manufacturing projects.
Trusted & Approved Vendor for Leading OEMs
End-to-End Coil Manufacturing with Custom Tooling & Fixtures
Our insulation systems for coils and bars
Coral Rich-Flex®
For coils up to 15KV
Coral®Rich-Flex™ is our bestselling Resin Rich (stage B) system for coils and bars.
Insulation class F, with fully cured and pressed slot portions.
Overhangs remain flexible, making rewinding easy.
Perfect for high voltage motors, small generators and hydro generator coils.
Ideal for demanding rewinding tasks due to its flexibility.
Coral Rich-Cured®
For coils and bars up to 15KV
Coral®Rich-Cured™ is our bestselling Resin Rich (stage B) system for bars and coils.
In addition to Coral Rich-Flex, Coral Resin Rich Cured is fully pressed in the slot portion, and in the overhangs using special fixtures making sure that there is no air voids and as such an ideal insulation, with ideal Partial Discharge levels.
Insulation class F with fully cured and pressed slot portions using special fixtures.
Ensures no air voids in the OH portion.
Ideal for power and hydro generators with all types of bars.
Perfect for applications requiring high reliability in coil insulation.
Coral Seal®
For low & medium voltage single bar
Coral®Seal™ is a single coil/bar VPI system with epoxy Anhydride class F insulation.
Coils are fully cured using a standard VPI system for precise dimensional accuracy.
Special fixtures ensure minimal voids in both straight and overhang parts.
Ideal for medium voltage motors, generators, turbo and hydro generator coils and bars.
Provides reliable insulation for demanding generator and motor applications.
Coral Hybrid Seal®
For single bar VPI systems up to 24KV
It is a single coil/bar VPI system with epoxy Anhydride class F insulation.
Coils/bars are fully cured using a standard VPI system for dimensional perfection.
Special fixtures ensure no voids in both straight and overhang parts.
Designed for high voltage turbo and hydro generator coils and bars.
Provides top-tier insulation reliability for high-demand generator applications.
Coral Green E®
For green coils
CoralGreenT® features an advanced insulation system for traction motors.
Globally impregnated with silicon for enhanced durability.
Provides excellent insulation performance in demanding traction motor environments.
Designed for long-lasting reliability and efficiency.
Ideal for traction motor applications requiring superior insulation solutions.
Coral Green T®
For green coils
CoralGreenT® is an insulation system designed for traction motors.
Globally impregnated with silicon for enhanced insulation protection.
Provides high durability and performance in traction motor applications.
Ideal for use in demanding environments requiring robust insulation.
Ensures long-lasting efficiency and reliability in traction motors.
Coral Green H™
For green coils
Coral®GreenH™ features an insulation system impregnated with Polyester/Polyester-imide class H resins.
Designed for high-performance insulation in demanding applications.
Provides enhanced thermal stability and durability.
Ideal for use in environments requiring Class H insulation standards.
Ensures long-lasting protection and efficiency for critical electrical components.
Specialised Expertise In Every Stage of Coil Manufacturing
1. Coil Design & Engineering
- Expert Coil Designers optimize conductor configurations for enhanced electrical performance, lower losses and improved heat dissipation.
- Advanced winding patterns & slot geometries ensure maximum efficiency in stator and rotor coils.
2. Robel Design & Analysis – Perfecting Winding Transitions & Joint Integrity
- Specialists in Robel Bar Design ensure seamless coil-to-coil connections with minimal resistance.
- Advanced shaping & profiling techniques enhance durability and conductivity.
- Joint resistance testing & metallurgical evaluation ensure optimal mechanical strength.
3. Insulation Scheme Development
- Custom insulation systems designed for high-voltage, high-temperature and moisture resistance.
- Expertise in mica-based and epoxy-resin-rich insulation for superior dielectric strength.
- Layer-by-layer insulation design ensures long-lasting performance in harsh environments.
4. Resin Selection & VPI Process Optimisation
- Material engineers select the best resins and varnishes for thermal class and chemical resistance.
- Vacuum Pressure Impregnation (VPI) specialists ensure deep resin penetration, preventing voids and ensuring mechanical robustness.
- Advanced curing cycles & thermal analysis to improve adhesion and endurance.
5. Final Coil Processing & Dimensional Validation
- Dimensional experts ensure coil geometry meets exact motor/generator core specifications.
- Quality control specialists verify coil alignment, ensuring zero tolerance deviations.
Technical Oversight
A dedicated team of experts oversees the entire coil manufacturing process, ensuring compliance with international electrical, mechanical and thermal standards. Their responsibilities include optimizing mechanical endurance, evaluating insulation integrity (thickness, creepage distance and corona resistance), ensuring superior dielectric bonding through advanced resin chemistry and validating final coil dimensions for perfect fitment and functional reliability.
Expertise-Driven Innovation at Coral Coil
- Dedicated Experts at each stage of coil manufacturing
- R&D-Backed Solutions that push performance boundaries
- Advisory Excellence in insulation, resin and winding tech
- Global Standards Compliance: IEC, IEEE, ISO
A Dynamic Team, Powered by Intelligence
- 90% of our workforce are next-gen engineers with a data-driven approach
- Senior advisors bring strategic insights from decades of experience
- Together, we drive efficiency, innovation and unmatched precision
Redesigning Performance: Re-Engineering Expertise
- Complete Re-Design of hydro and turbo generator bars
- Power Enhancements through conductor optimisation, insulation upgrades and advanced thermal management
- Customised Solutions built to match operational, voltage and site-specific demands
Trust with our
Certificates
We are backed by more than 9+ industry standards, including ISO, WRAS and FDA.
Why Us?
End To End
Coral Coil provides complete design and reverse engineering services for motors and generators. As an IMS-certified company (ISO 9001:2008, ISO 14001, ISO 18001), we handle everything from design to servicing coils and turbo bars for LT/HT motors and generators.
OEM
Each OEM has specific requirements and standards and at Coral, we ensure your needs are fully met. Often, we establish a dedicated production line and team for your recurring orders, ensuring they are well-trained to enhance quality, efficiency and timing.
Repair/Rewind
Coral Coil, born in the industry, grasps coil supply urgency. With short motor downtime, we prioritise emergency coil quotes, production and delivery. Strong supplier ties secure materials, while our shipper ensures swift, certified shipments.
Export
All customers are treated equally when shipping. We ensure safe, timely delivery with trusted logistics. Wooden mock-ups for fitment checks guarantee precise coil fitting, reducing on-site deformation risks.
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