The thermally upgraded insulation paper is made from 100% electric grade unbleached pulp, and upgrading is achieved by adding nitrogen to the paperpulp. We supply thermally upgraded kraft paper for transformer insulation systems that require better thermal aging performance than standard kraft paper.
TUP is mainly used for winding insulation, conductor wrapping, layer insulation, and insulation components in oil-immersed transformers. Chengrui Insulation can offer both green and natural color thermally upgraded paper.
Main Features:
â??E-Class 120�°C certified heat resistance for reliable thermal endurance
Electrical insulation kraft paper is supplied in rolls with different thicknesses and customized widths. We can arrange slitting, sample testing, export packing, and technical confirmation based on the customer's application and production line requirements.
Chengrui Insulation is a Chinese electrical insulation kraft paper supplier supplying cable manufacturers, transformer factories, electrical equipment producers, insulation converters and industrial distributors worldwide.
Our electrical insulation kraft paper is produced from high-purity cellulose fibers and is widely used for cable insulation, conductor wrapping, transformer insulation systems and laminated electrical insulation materials.
Available in customized thicknesses, widths and roll formats, our products can be supplied according to customer drawings, technical specifications and production requirements.
G10 and G11 epoxy fiberglass laminate sheets are high-strength electrical insulation materials made from glass fiber cloth impregnated with epoxy resin and laminated under heat and pressure. They combine excellent electrical insulation, mechanical strength, dimensional stability and moisture resistance, making them widely used in electrical equipment, transformers, motors, switchgear, fixtures and structural insulation parts.
Chengrui supplies both G10 epoxy fiberglass laminate sheet and G11 epoxy fiberglass laminate sheet and FR4 insulation sheet in different thicknesses, colors, sheet sizes and machined parts according to customer requirements. Standard sheets can be supplied directly, and custom cutting, CNC machining, drilling, milling and shape processing are available for insulation components.
G10 epoxy fiberglass laminate sheet is a rigid laminated insulation sheet made from epoxy resin and fiberglass cloth. It is one of the most commonly used epoxy glass laminate materials for electrical insulation and mechanical support.
G11 epoxy fiberglass laminate sheet is a higher-temperature epoxy fiberglass laminate. It is also made from epoxy resin and fiberglass cloth, but compared with G10, G11 is designed for better thermal performance and improved stability under elevated temperature conditions.
Type: Epoxy fiberglass laminated sheet
Thickness: 0.1mm-250mm
Standard Dimension: 1020*1220mm; 1220*2040mm; 1220*2440mm; 1020*2040mm; 1020*2040mm or customized.
Customized sizes available.
Thermal Class: G10- B Class 130â G11-F Class 155/H Class 180
Our transformer insulation pressboard support strips are manufactured using highly refined and purified insulating pressboard to ensure excellent performance in electrical applications. The material is carefully processed to achieve uniform thickness and is free from pinholes, undispersed fiber bundles, and other microscopic defects. This meticulous production process guarantees consistent quality and reliable insulation properties for your transformer applications.
The main types of Pressboard Support Strips:
R-Chamfered Support Strip / Radius Edge Support Strip
Non-Chamfered Support Strip / Square Edge Support Strip
Right-Angle Edge Support Strip
Applications and Functions of Insulation Support Strips:
â??Oil-Immersed Transformers:
Winding Fixation: Work together with upper and lower positioning rings and columnar spacers to create a robust mechanical support system, preventing winding short circuits or deformation.
Cooling Optimization: The spacing between insulation support strips directly influences oil flow. Elongated hole designs (e.g., 20-30 mm spacing, 5-8 mm diameter holes) increase the heat dissipation surface area.
Dry-Type Transformers:
Utilize high-temperature-resistant materials (e.g., Class F, 155C) to avoid softening or deformation under thermal stress.
â??Special Scenarios:
High-Humidity Environments: Employ anti-hygroscopic materials such as polyimide composites.
High-Frequency Transformers: Optimized dielectric properties help minimize partial discharge risks.
Transformer insulation pressboard is a rigid cellulose board used for barriers, spacers, cylinders and other structural insulation parts in oil-filled transformers. It offers good mechanical strength, dielectric insulation and oil compatibility.
Why Pressboard Is Used in Transformer Insulation
In transformers, insulation is not only an electrical issue. It is also a structural and mechanical issue.
That is why pressboard transformer insulation is widely used. Compared with thinner insulation papers, pressboard provides:
higher mechanical strength
better dimensional stability
stronger support for internal parts
good dielectric insulation
good performance in oil-immersed transformer systems
Diamond dotted paper (DDP) is an electrical insulation presspaper partially coated with heat-curable epoxy resin dots arranged in a diamond pattern. During coil drying / oven heating, the resin dots soften and cure to bond adjacent layers, helping improve winding mechanical stability in transformer manufacturing.
DDP insulation paper is commonly used as interlayer insulation between coils in oil-immersed transformers, where controlled bonding is needed without sacrificing oil impregnation and drying efficiency.
Chengrui Insulation can provide DDP insulation paper in rolls with different thicknesses, widths, and slitting options according to production requirements. Our team can help confirm roll size, resin dot pattern requirements, packing method, sample availability, and bulk order delivery schedule.
