DD-DMD Diamond Dotted Insulation Paper | Epoxy Resin Coated F-Class DMD for Oil-Immersed Transformers

DD-DMD Diamond Dotted Insulation paper is a highly specialized electrical insulation matrix explicitly designed for liquid-filled power environments. It is manufactured by applying an advanced, modified special heat-curable epoxy resin in a precise rhombus (diamond dot) pattern onto a high-performance F-grade DMD composite backing sheet.

During the oven-drying and curing process of transformer manufacturing, these diamond-shaped epoxy dots melt, flow slightly, and polymerize. This establishes extremely tight permanent adhesion joints with surrounding winding conductors while leaving clear un-coated network channels. The design ensures unobstructed, optimal oil circulation and cooling fluid dynamics within the coil, safely dispersing heat while preventing displacements.

Key Features & Advantages

• Optimized Oil Circulation & Thermal Dissipation: The unique diamond-dot configuration creates structured microscopic channels that allow transformer insulating oil to flow freely, maximizing heat dissipation and oil impregnation rates.

• Exceptional Short-Circuit Stress Resistance: Delivers high normal bonding strength (≥650 Kpa post-curing), effectively locking winding layers in place against harsh electrodynamic stresses caused by unexpected sudden short-circuits.

• High-Precision Diamond Coating: Features a consistent single-sided adhesive dot layer thickness of 6–12 μm, ensuring solid bonding dimensions without unwanted total blockage of oil paths.

• Premium Mechanical Tensile Profiles: Possesses excellent longitudinal tensile integrity (up to ≥160 N/10mm), making it highly reliable for tension-heavy automated wire winding machines.

Typical Applications 

DD-DMD is highly recommended for high-reliability oil-filled electrical equipment:

• Oil-Immersed Power Transformers: An excellent choice for high-strength inter-turn wrapping insulation of heavy power magnet wire conductors.

• Distribution Transformer Coils: Perfectly acts as the structural interlayer insulation barrier for multi-layer foil or wire-wound distribution systems.

• Motor & Special-Shaped Liners: Can be effectively utilized as tough lining insulation for specialized motors or oil-cooled apparatuses.

Technical Data Sheet 

Standard Specifications: 0.10mm – 0.20mm (Total custom thickness range: 0.11mm - 0.45mm available) | Width Range: 5mm – 1500mm (Custom slitting available)