Diamond Dotted Paper (DDP) is an electrical insulation material made from high-performance electrical-grade cable paper coated with a specially modified epoxy resin in a diamond-dot pattern.
Diamond Dotted Paper (DDP) is an electrical insulation material made from high-performance electrical-grade cable paper coated with a specially modified epoxy resin in a diamond-dot pattern.
It is primarily used for turn-to-turn and interlayer insulation in oil-immersed transformer windings. The heat-activated resin coating provides bonding between insulation layers during the winding drying process.
| No. | Parameter | Unit | Specification | |||||
| 1 | Substrate Thickness | mm | 0.08 | 0.13 | 0.18 | 0.20 | 0.25 | |
| 2 | Thickness of Singlesided Adhesive | µm | 515 | |||||
| 3 | Tensile Strength | MD | N/10 mm | ≥60 | ≥110 | ≥160 | ≥180 | ≥230 |
| CD | N/10 mm | ≥20 | ≥35 | ≥55 | ≥60 | ≥70 | ||
| 4 | Elongation | MD | % | ≥1.5 | ||||
| CD | % | ≥2.7 | ||||||
| 5 | Breakdown Voltage | In the air | kV | ≥0.88 | ≥1.37 | ≥2.00 | ≥2.10 | ≥2.25 |
| In the oil | kV | ≥4.4 | ≥7 | ≥9 | ≥9.8 | ≥11.50 | ||
| Nominal Thickness: 0.08 mm, 0.13 mm, 0.15 mm, 0.18 mm, 0.20 mm, 0.25 mm, 0.30 mm, 0.38 mm Nominal Width: 960 mm,1000 mm, 1250 mm, 1380 mm | ||||||||
Specification Confirmation:The values shown above represent common market options. Final dimensions, thermal class, performance requirements and inspection documents are confirmed before order.