Insulation Applications
Specialized insulation solutions engineered for critical electrical infrastructure. From high-voltage power transformers to industrial electrical apparatus, our materials ensure optimal performance, safety, and longevity in demanding operational environments.
Oil-Immersed Power Transformers
High-capacity power transmission and distribution transformers requiring robust insulation systems capable of withstanding extreme electrical and thermal stresses continuously.
Insulation Paper
Layer and turn insulation for HV windings, providing dielectric isolation between conductor layers in oil-filled environments up to 500kV class.
Transformer Board
End blocks, angle rings, and phase barriers creating oil ducts and mechanical support structures within winding assemblies.
Lead Exit Systems
Specialized insulation assemblies managing electric field distribution at winding terminations and bushing connections.
Core Clamping & Support Systems
Mechanical stabilization of transformer active parts requiring high compressive strength materials that maintain dimensional stability under heavy loads and thermal cycling.
Electrical Laminated Wood
Core support beams and upper/lower clamping plates providing rigid structural foundation with excellent oil compatibility and insulation properties.
Machined Components
CNC-precision spacers, blocks, and support structures maintaining exact tolerances for core lamination compression and winding support.
Laminated Wood Products
Finished pressure rings and insulation barriers processed for maximum oil absorption resistance and long-term mechanical integrity.
HV Bushings & Lead Management
Critical interface areas between transformer windings and external circuitry where concentrated electric fields require sophisticated insulation coordination and partial discharge prevention.
Lead Exit Assemblies
Comprehensive insulation systems for winding terminations, managing step potentials and ensuring reliable connection to external bushings.
Transformer Board Components
Precision-machined barriers and shields controlling electric field distribution in high-voltage lead exit zones.
Insulation Paper Wraps
Protective layering for lead conductors transitioning from oil-immersed windings to bushing terminals.
Industrial & Specialty Transformers
Furnace transformers, rectifier units, and converter applications exposed to severe thermal cycling, harmonic stresses, and demanding mechanical duty cycles.
High-Density Laminated Wood
Enhanced structural components for heavy-current applications requiring superior compressive strength and thermal shock resistance.
Custom Machined Parts
Application-specific insulation components engineered for unique spatial constraints and thermal management requirements in industrial units.
Composite Insulation Systems
Integrated combinations of insulation paper, board, and laminated wood optimized for specific industrial transformer designs.
Technical FAQ
Common questions about insulation material selection, specifications, and application engineering for transformer manufacturing
Our insulation materials cover the complete range of transformer applications from distribution to ultra-high voltage. Insulation paper and board are suitable for systems up to 500kV and above, with specific grades available for:
- Distribution transformers (≤36kV): Standard kraft paper and TIV board
- Medium power (36-170kV): High-density pressboard with enhanced dielectric strength
- High power (170-420kV): Super-calendered insulation board with controlled oil impregnation
- UHV (≥420kV): Premium grade materials with customized density profiles and partial discharge optimization
All materials comply with IEC 60641 and IEC 60554 standards, with batch-specific test reports available.
The selection depends on the functional requirements within the transformer geometry:
- Insulation Paper: Ideal for conformable wrapping applications—inter-turn insulation, layer insulation, and lead wrapping where flexibility and crease resistance are critical. Available in thicknesses from 0.08mm to 0.50mm.
- Transformer Board (Pressboard): Used for rigid structural components—end blocks, angle rings, phase barriers, and oil ducts. Provides mechanical support and maintains fixed geometry under compression. Thickness range 1.0mm to 8.0mm standard, thicker available on request.
- Electrical Laminated Wood: Specified for high-compressive-load applications such as core support beams, clamping plates, and pressure rings where both insulation integrity and mechanical strength are required.
Our engineering team can provide material selection guidance based on your specific transformer design parameters.
Yes, we offer comprehensive CNC machining services for insulation components. Our capabilities include:
- 5-axis CNC machining for complex geometries (curved barriers, 3D oil ducts)
- Tight tolerance control (±0.1mm for critical dimensions)
- Volume flexibility: From prototype batches to high-volume production runs
- Material options: Transformer board, laminated wood, or composite sandwich constructions
- Value-added services: Pre-drying, oil impregnation preparation, surface treatments
We work from customer CAD files (STEP, IGES, DXF formats accepted) and can provide design for manufacturability feedback to optimize insulation performance while controlling costs.
We maintain comprehensive quality management systems aligned with international standards:
- System Certifications: ISO 9001:2015 (Quality Management), ISO 14001:2015 (Environmental Management)
- Product Standards: Full compliance with IEC 60641-1 (Pressboard), IEC 60554 (Insulating Paper), ASTM D3393
- Batch Testing: Every production lot includes certificate of analysis covering:
- Dielectric strength (breakdown voltage)
- Density and thickness uniformity
- Moisture content
- Conductivity and pH of aqueous extract
- Air permeability (for oil impregnation)
- Special Testing: Partial discharge evaluation, thermal aging analysis, and mechanical compression tests available upon request
Full material traceability is maintained from raw fiber source through finished product.
We specialize in export packaging designed to protect insulation materials during long-distance sea and air freight:
- Moisture Protection: Vacuum-sealed aluminum barrier packaging with desiccant for ocean freight (essential for maintaining material dielectric properties)
- Mechanical Protection: Rigid wooden crates or reinforced cardboard cartons with shock-absorbing layers; corner protection for machined components
- Packaging Formats:
- Rolls: Diameter up to 1.2m, width 500mm-2500mm (paper)
- Sheets: Flat pack or palletized (board and wood)
- Machined parts: Individual foam wrapping with assembly drawings included
- Logistics: FOB, CIF, and DDP Incoterms available; established relationships with freight forwarders for efficient customs clearance
- Documentation: Comprehensive export packing lists, certificates of origin, and material safety data sheets provided
Typical lead times: 3-4 weeks for standard materials, 6-8 weeks for customized machined components.
Proper storage is critical to maintaining insulation performance:
- Temperature: Store in dry, covered areas between 5°C and 40°C. Avoid direct sunlight which can cause thermal aging.
- Humidity: Relative humidity must be kept below 60%. Our vacuum packaging should remain sealed until immediately before use.
- Orientation: Store rolls vertically on original pallets; lay flat sheets horizontally on level surfaces to prevent warping. Do not stack heavy items on top of insulation materials.
- Handling: Use clean gloves when handling to prevent contamination; machined components should be lifted by support surfaces, not thin edges.
- Pre-Processing: Before transformer assembly, materials typically require drying in an oven (105°C) to reduce moisture content to <0.5% for optimal oil impregnation.
When stored properly in original packaging, our materials have a shelf life of 24 months from production date.
Voltage Classes
- Distribution: Up to 36kV
- Medium Power: 36kV - 170kV
- High Power: 170kV - 420kV
- Ultra High Voltage: 420kV+
Operating Conditions
- Thermal Class A (105°C)
- Oil Immersed Environments
- Continuous Operation
- Overload Capable
Industry Standards
- IEC 60641 (Pressboard)
- IEC 60554 (Insulating Paper)
- ASTM D3393
- Customer Specifications
Application Engineering Support
Our technical team provides application-specific insulation design assistance, material selection guidance, and customized solutions for your transformer manufacturing requirements.
Contact Engineering Team