Professional Manufacturer of DDP Insulation Paper for Transformers

In the manufacturing process of transformers, inductors, and motors, the secure fixing of coils and long-term insulation stability are key factors determining product lifespan and operational reliability. During equipment operation, vibration, thermal expansion and contraction, and harsh operating conditions can cause coil loosening, leading to operating noise, mechanical wear, and in severe cases, short-circuit failure.

DDP (Diamond Dotted Paper) is an insulating material developed to address this technical problem. It uses special insulating paper as a base material and is made by precisely coating thermally active epoxy resin dots. During the transformer impregnation and baking process, the adhesive dots melt and solidify upon heating, forming an adhesive bond between the coil and the frame, and between coils themselves, creating a stable whole. Choosing a professional DDP adhesive paper manufacturer directly affects product safety performance, lifespan, and the reliability of equipment under long-term load operation.

DDP Insulation Paper Features

Thermally curing adhesion performance: Achieves strong coil bonding during transformer hot-pressing processes, improving equipment mechanical strength.

Heat resistance ratings: DDP is available in multiple grades, such as 105℃, 120℃, and 130℃. And it is suitable for various operating conditions.

Dielectric strength and withstand voltage performance: Meets the electrical performance requirements of insulation structures.

Suitable applications: DDP can be used in the internal insulation systems of oil-immersed transformers.

DDP Insulation Paper Application Scenarios

1. Distribution Transformers

Used for:

Interlayer insulation

Inter-turn insulation

Coil fastening and bonding

DDP paper effectively improves short-circuit withstand capability.

2. Power Transformers (66kV / 110kV / 220kV)

Improves conductor structural stability.

Prevents coil displacement due to short-circuit electrodynamics.

Enhances overall mechanical strength and dielectric properties.

3. Dry-type Transformers and Instrument Transformers

Used for interlayer coil support, improving heat and pressure resistance.

Core Advantages of Professional DDP Paper Manufacturers

1. Production Experience

Professional manufacturers have many years of production experience, with mature and stable processes, ensuring consistent product quality.

The engineering team understands transformer design and manufacturing process requirements and can provide product solutions tailored to customer needs.

2. Full-Process Quality Control

Quality inspection standards are set for each stage, including raw material procurement, precision coating, slitting, and packaging. Professional manufacturers use online monitoring systems to comprehensively test the consistency, thickness, width, and electrical performance of adhesive dots on outgoing products, ensuring product quality compliance. 

3. Customized Production Service

Professional manufacturers offer the following customized services to meet the needs of different customers and transformer models:

Substrate Customization: Professional manufacturers provide insulating paper of various thicknesses and materials, such as T4, T410, and NHN, or PET film.

Adhesive Dot Customization: Professional manufacturers adjust the shape (round, square), distribution density, coating amount, and adhesive type of the adhesive dots according to customer process requirements.

Customized Slitting Size: Professional manufacturers precisely slit the material to the width and length required by the customer, reducing secondary processing steps.

4. Supply Chain and Response System

A professional manufacturer serving the global market has efficient logistics and supply chain system, which ensures on-time order delivery. Customers can obtain technical support and product supply services globally.

5. Possess Multiple International Tests

Professional transformer DDP paper manufacturers typically provide:

Heat resistance rating report (IEC 60216)

Dielectric strength test (IEC 60243)

Adhesion strength test

RoHS, REACH environmental certification

DDP Paper Supplier Selection Criteria

Automated dispensing production line configuration: Affects dot quality and production stability.

Heat resistance rating and resin curing temperature parameters: Affect compatibility with transformer hot pressing processes.

Test reports: Dielectric performance, adhesion strength, and other test reports are required, conforming to export market and industry standards.

Roll material physical properties: Roll flatness and dot detachment resistance affect coil winding efficiency.

Customization services: Supports customization requirements for width, thickness, packaging, etc.

FAQs

Q1: What are the typical curing conditions for DDP paper?

A1: Typical curing conditions are 120℃-150℃ for 30 minutes to 1 hour. Specific parameters need to be adjusted according to the type of impregnation paint and baking process used by the customer. The company can provide technical guidance.

Q2: Do you provide sample testing?

A2: Sample testing is supported. Customers can use the form on the company website or contact us directly to explain their application requirements, and the company will send matching samples.