Diamond Dot-painted Insulating Paper(DDP)

Diamond Dot-painted Insulating Paper (DDP) is a double-sided diamond-patterned insulating material made by coating a composite epoxy resin adhesive in a diamond-shaped dot pattern onto an electrical insulating paper substrate using special equipment, followed by baking and drying. This product typically uses cable paper or PMP paper as the substrate, with precisely designed adhesive dots (e.g., 9.4mm x 9.4mm dots, 6.5mm spacing). During heating, the adhesive layer melts and bonds to the windings, and after cooling and curing, it forms a high-mechanical-strength insulating structure. Compared to ordinary insulating paper or monolithically coated materials, the diamond-patterned design of Diamond Dot-painted Insulating Paper (DDP) ensures strong adhesion between insulating paper layers in transformer windings, while the dotted gaps ensure effective penetration of insulating oil and expulsion of internal gases, significantly reducing the risk of partial discharge and corona discharge, and improving the reliability of the insulation system. Furthermore, this material can be directly used for insulation of foil coils and enameled wire coils, eliminating the need for impregnation, saving raw materials and energy, while improving heat dissipation and extending service life.

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Description
Applications
Parameter

Features:
Structure and Process: This product typically uses high-performance cellulose insulating paper as the matrix, its surface coated with an epoxy resin system of a specific chemical composition using specialized equipment, forming regular, discontinuous diamond or dotted patterns.
Adhesion Mechanism: During the drying and curing process after coil manufacturing, DDP is heated to the activation temperature of the epoxy resin, causing the resin dots to melt and flow. Under continuous heating, the resin undergoes a cross-linking reaction and cures, firmly bonding adjacent conductors, foil layers, or insulating materials together.
Mechanical Properties: After the resin cures, it forms an adhesive between the layers of the transformer coil, thereby improving the overall structural integrity of the coil. This helps limit the displacement of the winding under electromagnetic forces.
Electrical and Oil Impregnation Properties: Its dotted structure ensures that most areas of the insulating paper remain open, facilitating the penetration and flow of transformer oil. This characteristic is beneficial for establishing the dielectric strength of the insulation system and dissipating heat.

About

Zhejiang Yuanda Fiberglass Mesh Co.,ltd.

Zhejiang Yuanda Fiberglass Mesh Co., Ltd. was founded in 2000. It is a technology-oriented manufacturing enterprise focusing on the new materials field, specializing in the research and development and production of composite reinforcing materials, insulating materials, and related intelligent equipment. Committed to providing professional and reliable products and services to customers worldwide. The company is located in the Yangtze River Delta economic Circle of China, close to Ningbo Port and Shanghai Port. The unique geographical location has brought convenience to the company's import and export business. The company covers an area of nearly 33,000 square meters and has modern standard workshops.
The three core business segments
1. Composite material fiber bars and fiber bar mesh sheets (GFRP), as well as supporting production equipment.
2. Special interlayer insulating materials for power transformers and motors.
Iii. Alkali-resistant fiberglass mesh fabric and alkali-resistant emulsion for construction.

For the past 25 years, Zhejiang Yuanda Fiberglass Mesh Co., Ltd. has been deeply engaged in the field of new materials, deepening technological innovation and industrial collaboration, continuously expanding the application scope of its products, and has won wide recognition from customers. In the future, we will be committed to building a leading domestic supplier of composite new materials and injecting continuous impetus into the high-quality development of the industry.

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No. 60, Yiwu East Road, Wufu Industrial Park, Yiting Town, Shangyu City, Zhejiang Province, China

+86 13606593503

0575-82419001

fiberglassmesh@163.com

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Property		Unit	Values
Thickness of base paper		mm	0.08±0.005	0.13±0.007	0.18±0.01	0.20±0.01	0.25±0.01
Density of base paper		g/m³	0.85-1.1	0.85-1.1	0.85-1.1	0.85-1.1	0.85-1.1
One-sided adhesive thickness		u m	10-15	10-15	10-15	10-15	10-15
Moisture		％	4.0-8.0	4.0-8.0	4.0-8.0	4.0-8.0	4.0-8.0
Welding strength	Room temperature		650	650	650	650	650
Welding strength	100℃±2℃		400	400	400	400	400
Oil absorption		%≥	200	200	200	200	200
For the pollution of transformer oil			Free from contamination(tan8<0.001)
For the pollution of transformer oil			Free from contamination(tan8<0.001)
Tensile strength	MD	N/10m mwidth ≥	60	110	160	1 80	230
Tensile strength	CMD	N/10m mwidth ≥	30	50	70	80	1 00
Tensile strength	MD	mN≥	450	900	1350	1 500	2000
Tensile strength	CMD	mN≥	500	1 000	1500	1 700	2300
Breakdown Voltage	In air	Kv≥	0.88	1.37	2	2.1	2.25
Breakdown Voltage	In oil	Kv≥	4.4	7	9	9.8	11.5

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