Electrical Grade Clackband
ACC Insulations is a leading Clackband manufacturer in Maharashtra, India, offering high-quality and durable Clackbands for liquid-filled power and distribution transformers.
Clackband is a highly specialized distancing and spacing element. It consists of pre-compressed pressboard blocks firmly glued to a high-quality electrical insulating paper carrier tape. ACC Insulation produces Clackband from 100% sulphate pulp of electrical-grade quality to deliver superior oil absorption alongside high purity.
When integrated directly into the winding process, our precision-engineered Clackbands create essential axial and radial cooling channels, allowing dielectric oil to flow freely and dissipate heat efficiently without compromising structural integrity.
The Science of Cooling Channels
During the operation of a power transformer, copper losses generate intense heat within the windings. If this heat is not effectively dissipated, the thermal load will degrade the surrounding paper insulation, dramatically shortening the lifespan of the transformer.
Clackbands act as the architectural framework for the transformer's internal cooling system. By maintaining precise, uniform gaps between winding layers, Clackband ensures that insulating oil can circulate continuously, extracting heat from the core while simultaneously acting as a liquid dielectric barrier.
Key Technical Specifications
- 100% Sulphate Wood Pulp: Both the carrier paper and the spacer blocks are manufactured from pure, unbleached electrical-grade cellulose, ensuring zero contamination.
- Optimal Oil Absorption: The specific density of our pressboard blocks allows for rapid and complete impregnation by transformer oil under vacuum drying, preventing deadly air voids.
- Thermal Class A (105ºC): Fully compliant with international electrical standards, providing long-lasting thermal endurance under continuous load.
- High Mechanical Rigidity: Pre-compressed blocks withstand severe radial and axial compression forces during short-circuit events, keeping copper windings locked in place.
- Adhesive Reliability: We utilize specialized, transformer-oil-compatible adhesives that will not degrade, separate, or contaminate the dielectric fluid.
Available Variants & Applications
Clackbands are primarily used to form cooling channels and provide purely mechanical duct spacing in disc-type and multi-layer transformer windings. We supply them in large, continuous rolls for highly automated winding equipment.
- Shape 3 (Rectangular Strips): Standard straight-edged blocks ideal for uniform channel distancing and disc-type windings.
- Shape 4 (Trapezoidal / V-Strips): Angled, bevel-cut blocks designed to perfectly match the curvature of cylindrical and helical winding assemblies, ensuring a flush fit against the copper wire.
Why Choose ACC Insulations?
With three decades of expertise in Nashik, Maharashtra, we don't just supply raw materials; we deliver engineering reliability. When you source Clackband from ACC Insulations, you are guaranteed:
- Precision slitting and block fabrication with strict dimensional tolerances.
- Adhesives proven to withstand harsh vacuum drying cycles without delamination.
- Custom configurations manufactured to your exact engineering specifications.
- Reliable, bulk-scale production capacity to meet your production timelines.
Engineering Tools Suite
Calculate precise cooling channel spacing and thermal flow requirements for your Clackband applications using our interactive tools.
Frequently Asked Questions
Yes. We can manufacture the pressboard blocks in various thicknesses (typically ranging from 1mm to 8mm+) and adjust the distance between each block on the carrier paper to match your specific thermal flow calculations and winding designs.
No. We use a highly specialized, heat-resistant adhesive that is completely compatible with transformer oils. It is engineered to withstand the extreme heat and pressure of the vacuum vapor-phase drying process without delaminating or leaching impurities into the oil.
Shape 3 features standard rectangular blocks with 90-degree edges, best suited for flat or large-radius layers. Shape 4 features trapezoidal (beveled) edges. This angled design allows the blocks to sit perfectly flush against the tight curve of cylindrical windings without creating pressure points on the copper wire.
Because Clackband is made entirely of cellulose (Kraft paper and pressboard), it is highly hygroscopic (absorbs moisture). It must be stored in a clean, dry, and climate-controlled environment wrapped in protective film until it is ready to be used on the winding floor.
