Transformer Pressboard Cylinders

Chengrui Insulation supplies transformer pressboard cylinders for power transformer manufacturers, distribution transformer factories, transformer repair workshops and insulation component distributors worldwide.

Our pressboard cylinders are manufactured from high-density electrical transformer pressboard and are widely used as primary insulation structures between transformer windings. Available in customized diameters, heights and thicknesses, these cylinders can be produced according to customer drawings, technical specifications or transformer design requirements.

What Are Pressboard Cylinders?

A pressboard cylinder is a rigid cylindrical insulation component made from transformer pressboard.

It is commonly installed between:

• high-voltage windings

• low-voltage windings

• winding assemblies and core structures

The cylinder acts as both an electrical insulation barrier and a mechanical support structure.

In oil-filled transformers, pressboard cylinders are often combined with:

• pressboard strips

• oil duct strips

• ladder ducts

• insulation spacers

to create an efficient oil circulation and insulation system.

Main Functions of Transformer Pressboard Cylinders

1. Primary Insulation Barrier: The cylinder separates different winding sections and maintains safe electrical insulation distances.

2. Mechanical Support: The rigid pressboard structure helps maintain winding geometry and withstand mechanical forces during transformer operation and short-circuit events.

3. Oil Duct Formation: Pressboard cylinders are often combined with oil duct strips to create cooling channels that allow transformer oil to circulate efficiently.

4. Structural Stability: The cylinder supports winding assemblies and helps prevent deformation during transportation and operation.

Product Features

Pressboard cylinders can be manufactured from Transformer Pressboard, High Density Pressboard or laminated pressboard, with advantages of :

1. Excellent Electrical Insulation

Provides reliable dielectric separation between winding structures.

2. High Mechanical Strength

 Supports heavy winding structures and resists deformation.

3. Excellent Oil Compatibility

Suitable for long-term operation in mineral oil and ester oil transformer systems.

4. Stable Dimensions

Maintains shape and dimensional accuracy during operation.

5. Good Machinability

Can be cut, drilled and fabricated into customized transformer insulation components.

Available Dimensions

Pressboard cylinders can be supplied according to customer drawings or specifications.

Common customization options include:

Inner Diameter: Typically produced according to winding diameter requirements.

Thickness: Customized according to insulation design.

Height: Available according to transformer winding height.

Special Machining like slots holes cut-outs assembly features can be fabricated if required.

Typical Applications

Power Transformers:  Used as main insulation cylinders between HV and LV windings.

Distribution Transformers:  Provides insulation support and oil channel structure.

Oil-Immersed Transformers:  Widely used in both conventional mineral oil and ester-filled transformer systems.

Transformer Repair Projects: Replacement cylinders can be produced according to existing samples or drawings.

Chengrui Insulation manufactures and supplies transformer pressboard cylinders for transformer manufacturers, EPC contractors, transformer repair companies and insulation component distributors.

For transformer projects, our engineering team can assist with material selection, dimensional review and production feasibility before mass production.