D279 Epoxy Pre-impregnated DMD for dry type trasnformers
D279 is made from DMD and special epoxy heat resistant resin. It has the characteristics of long storage life, low curing temperature and short curing time. After being cured, it has excellent electrical properties, good adhesive and heat resistance.The heat resistance is Class F. It is also called as Prepreg DMD, pre-impregnaed DMD, flexible composite insulation paper for dry transformers.
Product Features
D279 epoxy pre-impregnated DMD has excellent electrical properties, good adhesive and heat resistance.
Applications
D279 epoxy pre-impregnated DMD is used for layer insulation or liner insulation of low-voltage copper/ aluminum foil winding in dry-type transformers as well as slot insulation and liner insulation in Class B and F electric motors and electric appliances. It is also called as Prepreg DMD, Prepreg insulation composite paper for dry type transformers.
Supply Specifications
Nominal width：1000 mm.
Nominal weight: 50±5kg /Roll.
The splices shall not be more than 3 in a roll.
Color: white or red color.
Appearance
Its surface should be flat, free of uneven resin and impurities affecting performances. While being de-coiled, its surface shall not be conglutinated each other. Free of such defects such as creases, bubbles and wrinkles.
Packing And Storage
D279 should be wrapped with plastic film then put in clean & dry carton
The storage life is 6 months at temperature of below 25℃ after leaving factory. If the storage duration is over 6 months, the product can still be used when being tested to be qualified. The product should be put and/or stored upright and keep away from fire, heat and direct sunshine.
Technical Performances
The standard performance values for D279 epoxy pre-impregnated DMD are shown in table 1 and the typical values are shown in table 2.
Table 1: Standard Performance value for D279 epoxy Prpreg DMD
| No. | Properties | Unit | Stand values | ||||
| 1 | Nominal thickness | mm | 0.16 | 0.18 | 0.20 | 0.23 | 0.25 |
| 2 | Thickness tolerance | mm | ±0.030 | ±0.035 | |||
| 3 | Grammage (for reference) | g/m2 | 185 | 195 | 210 | 240 | 270 |
| 4 | Tensile strength (MD) | N/10mm | ≥70 | ≥80 | ≥100 | ||
| 5 | Dissolvable resin content | g/m2 | 60±15 | ||||
| 6 | Volatile content | % | ≤1.5 | ||||
| 7 | Dielectric strength | MV/m | ≥40 | ||||
| 8 | Shear strength under tension | MPa | ≥3.0 | ||||
Table 2: Typical performance values for D279 epoxy Prepreg DMD
| No. | Properties | Unit | Typical values | ||||
| 1 | Nominal thickness | mm | 0.16 | 0.18 | 0.20 | 0.23 | 0.25 |
| Thickness tolerance | mm | 0.010 | 0.015 | ||||
| 2 | Grammage (for reference) | g/m2 | 186 | 198 | 213 | 245 | 275 |
| 3 | Tensile strength (MD) | N/10mm | 100 | 105 | 115 | 130 | 180 |
| 4 | Dissolvable resin content | g/m2 | 65 | ||||
| 5 | Volatile content | % | 1.0 | ||||
| 6 | Dielectric strength | MV/m | 55 | ||||
| 7 | Shear strength under tension | MPa | 8 | ||||
Application and Remarks
Recommended curing conditions
Table 2
| Temperature（℃） | 130 | 140 | 150 |
| Curing time（h） | 5 | 4 | 3 |
Production Equipment
We have two lines, the production capacity is 200T/month.
